![]() De Beaufort, Carine ![]() in Lancet (2000), 355 BACKGROUND: To study the epidemiology of childhood-onset type 1 insulin-dependent diabetes in Europe, the EURODIAB collaborative group established in 1988 prospective geographically-defined registers of ... [more ▼] BACKGROUND: To study the epidemiology of childhood-onset type 1 insulin-dependent diabetes in Europe, the EURODIAB collaborative group established in 1988 prospective geographically-defined registers of new cases diagnosed under 15 years of age. This report is based on 16 362 cases registered during the period 1989-94 by 44 centres representing most European countries and Israel and covering a population of about 28 million children. METHODS: Multiple sources of ascertainment were used in most centres to validate the completeness of registration by the capture-recapture method. Trends in incidence during the period were analysed by Poisson regression, the data from centres within each country being pooled. FINDINGS: The standardised average annual incidence rate during the period 1989-94 ranged from 3.2 cases per 100000 per year in the Former Yugoslav Republic of Macedonia to 40.2 cases per 100000 per year in two regions of Finland. By pooling over all centres, the annual rate of increase in incidence was 3.4% (95% CI 2.5-4.4%), but in some central European countries it was more rapid than this. Pooled over centres and sexes, the rates of increase were 6.3% (4.1-8.5%) for children aged 0-4 years, 3.1% (1.5-4.8%) for 5-9 years, and 2.4% (1.0-3.8%) for 10-14 years. INTERPRETATION: The results confirm a very wide range of incidence rates within Europe and show that the increase in incidence during the period varied from country to country. The rapid rate of increase in children aged under 5 years is of particular concern. PMID: 10752702 [PubMed - indexed for MEDLI [less ▲] Detailed reference viewed: 101 (0 UL)![]() ![]() Mein, Georg ![]() in Kleist-Jahrbuch (2000) Detailed reference viewed: 111 (2 UL)![]() ![]() Tröhler, Daniel ![]() in Neue Pestalozzi-Blätter (2000), 6(1), 42-44 Detailed reference viewed: 63 (1 UL)![]() van Dam, Tonie ![]() in EOS (2000), 81(37), 421-427 Detailed reference viewed: 148 (3 UL)![]() Michels, Andreas ![]() in Journal of Applied Physics (2000), 87(9), 5953-5955 We present a new method for determining the exchange-stiffness constant A of a ferromagnetic bulk material by field-dependent elastic small-angle neutron scattering (SANS). In the limit of high applied ... [more ▼] We present a new method for determining the exchange-stiffness constant A of a ferromagnetic bulk material by field-dependent elastic small-angle neutron scattering (SANS). In the limit of high applied magnetic field H, for which the scattering volume is a single magnetic domain and the magnetization is nearly aligned with the direction of the applied field, a combination of micromagnetics theory with neutron scattering formalism suggests closed-form expressions for the differential scattering cross section as a function of the scattering vector and of H. Based on these results it is suggested that the exchange-stiffness constant can be extracted from experimental SANS data recorded as a function of H. At ambient temperature we have applied this method to polycrystalline cold-worked Ni and nanocrystalline electrodeposited Ni, finding exchange-stiffness constants of (8.2±0.2)×10−12 and (7.6±0.3)×10−12 J/m, respectively. Measurement at 5 K yields a value of (9.2±0.2)×10−12 J/m for the nanocrystalline sample, a temperature dependence that agrees qualitatively with data in the literature. In addition to the value of A, the technique supplies information on the spatial structure of the magnetic anisotropy field. [less ▲] Detailed reference viewed: 144 (11 UL)![]() ![]() Cuniberti, Gilles ![]() in Juris-Classeur périodique (2000) Contrôle de la procédure suivie par les arbitres. Detailed reference viewed: 43 (0 UL)![]() Michels, Andreas ![]() in Philosophical Magazine Letters (2000), 80 In ferromagnets with a non-uniform magnetocrystalline and/or magnetoelastic anisotropy, such as nanocrystalline or cold-worked polycrystalline materials, the static magnetic microstructure gives rise to ... [more ▼] In ferromagnets with a non-uniform magnetocrystalline and/or magnetoelastic anisotropy, such as nanocrystalline or cold-worked polycrystalline materials, the static magnetic microstructure gives rise to elastic magnetic small-angle neutron scattering (SANS). The paper explores a method for determining the exchange-stiffness constant A by analysis of the dependence of the elastic SANS cross-section on the applied magnetic field. Experimental results for A and for the spin-wave stiffness constant D in cold-worked or nanocrystalline Ni and Co are found to agree with literature data obtained by inelastic neutron scattering on single-crystal specimens. [less ▲] Detailed reference viewed: 179 (4 UL)![]() ![]() ; ; et al in FEBS Letters (2000), 470(1), 15-9 The interleukin-6 (IL-6) receptor complex comprises the IL-6 receptor (IL-6R, gp80) and the signal transducer gp130. Binding of IL-6 to its receptor results in dimerization of gp130, activation of the Jak ... [more ▼] The interleukin-6 (IL-6) receptor complex comprises the IL-6 receptor (IL-6R, gp80) and the signal transducer gp130. Binding of IL-6 to its receptor results in dimerization of gp130, activation of the Jak/STAT pathway, and in a down-regulation of IL-6 binding sites by endocytosis. The STAT activation after stimulation is transient, being maximal after 15-30 min and disappearing after 60-90 min. The mechanism which leads to the termination of the signal is still unknown.In this paper we have studied whether the down-modulation of the STAT signal requires the endocytosis of the receptor complex. Our results suggest that the desensitization of the IL-6 signal is not due to internalization of the receptor complex but requires de novo protein synthesis. [less ▲] Detailed reference viewed: 107 (1 UL)![]() ![]() ; ; et al in Nature Genetics (1999), 22(4), 336-45 Detailed reference viewed: 228 (15 UL)![]() Marichal, Jean-Luc ![]() ![]() in Fuzzy Sets and Systems (1999), 102(2), 293-314 This paper deals with the characterization of some classes of aggregation functions often used in multicriteria decision making problems. The common properties involved in these characterizations are ... [more ▼] This paper deals with the characterization of some classes of aggregation functions often used in multicriteria decision making problems. The common properties involved in these characterizations are "increasing monotonicity" and "stability for positive linear transformations". Additional algebraic properties related to associativity allow to completely specify the functions. [less ▲] Detailed reference viewed: 105 (5 UL)![]() ; ; Schiltz, Christine ![]() in NeuroImage (1999), 9(3), 278289 Most brain imaging studies on face perception have investigated the processing of unknown faces and addressed mainly the question of specific face processing in the human brain. The goal of this study was ... [more ▼] Most brain imaging studies on face perception have investigated the processing of unknown faces and addressed mainly the question of specific face processing in the human brain. The goal of this study was to highlight the effects of familiarity on the visual processing of faces. Using [15O]water 3D Positron Emission Tomography, regional cerebral blood flow distribution was measured in 11 human subjects performing an identical task (gender categorization) on both unknown and known faces. Subjects also performed two control tasks (a face recognition task and a visual pattern discrimination task). They were scanned after a training phase using videotapes during which they had been familiarized with and learned to recognize a set of faces. Two major results were obtained. On the one hand, we found bilateral activations of the fusiform gyri in the three face conditions, including the so-called fusiform-face area, a region in the right fusiform gyrus specifically devoted to face processing. This common activation suggests that different cognitive tasks performed on known and unknown faces require the involvement of this fusiform region. On the other hand, specific regional cerebral blood flow changes were related to the processing of known and unknown faces. The left amygdala, a structure involved in implicit learning of visual representations, was activated by the categorization task on unknown faces. The same task on known faces induced a relative decrease of activity in early visual areas. These differences between the two categorization tasks reveal that the human brain processes known and unknown faces differently. [less ▲] Detailed reference viewed: 102 (2 UL)![]() Marichal, Jean-Luc ![]() ![]() in IEEE Transactions on Fuzzy Systems (1999), 7(1), 93-96 This paper deals with a characterization of a class of aggregation operators. This class concerns operators which are symmetric, increasing, stable for the same positive linear transformations and present ... [more ▼] This paper deals with a characterization of a class of aggregation operators. This class concerns operators which are symmetric, increasing, stable for the same positive linear transformations and present a property close to the bisymmetry property: the ordered bisymmetry property. It is proved that the class investigated contains exactly the ordered weighted averaging operators (OWA) introduced by Yager in 1988. [less ▲] Detailed reference viewed: 104 (7 UL)![]() Schiltz, Christine ![]() in NeuroImage (1999), 9(1), 46-62 Using 15O-water 3D positron emission tomography, regional cerebral blood flow was measured twice in six human subjects: before and after extensive training in orientation discrimination. In each session ... [more ▼] Using 15O-water 3D positron emission tomography, regional cerebral blood flow was measured twice in six human subjects: before and after extensive training in orientation discrimination. In each session subjects performed two orientation discrimination tasks, during which they discriminated the orientation of a grating at either the trained or untrained reference orientation, and a control task, during which they detected a randomly textured pattern. By comparing the discrimination to the detection tasks, we observed a main effect of task bilaterally in the posterior occipital cortex, extending into the left posterior fusiform gyrus and the right inferior occipital gyrus, bilaterally in the intraparietal sulcus, as well as in the cerebellum, thalamus, and brainstem. When we compared the activation pattern before and after the training period, all the changes observed were activity decreases. The nonspecific changes, which were not related to the orientation used during the training, were situated in the cerebellum and bilaterally in the extrastriate visual cortex. The orientation-specific changes, on the other hand, were restricted to the striate and extrastriate visual cortex, more precisely the right calcarine sulcus, the left lingual gyrus, the left middle occipital, and the right inferior occipital gyrus. These findings confirm our hypothesis concerning the existence of learning related changes at early levels of visual processing in human adults and suggest that mechanisms resulting in neuronal activity decreases might be involved in the present kind of learning. [less ▲] Detailed reference viewed: 111 (2 UL)![]() ![]() ; Behrmann, Iris ![]() in Biochemical Journal (1999), 339 (Pt 1) Leukaemia inhibitory factor (LIF) signals via a heterodimeric receptor complex comprised of the LIF receptor (LIFR) and the interleukin (IL)-6 signal transducer gp130. Upon binding to its cognate receptor ... [more ▼] Leukaemia inhibitory factor (LIF) signals via a heterodimeric receptor complex comprised of the LIF receptor (LIFR) and the interleukin (IL)-6 signal transducer gp130. Upon binding to its cognate receptor LIF is internalized. In this study, we show that the LIFR is endocytosed independently of gp130. By using a heterochimaeric receptor system we identified a dileucine-based internalization motif within the cytoplasmic domain of the LIFR. Our findings suggest that a heterodimeric LIFR/gp130 complex and homodimeric gp130/gp130 complex are endocytosed via distinct internalization signals. [less ▲] Detailed reference viewed: 63 (0 UL)![]() ; ; et al in Physical Review Letters (1999), 83(19), 3948-3951 We have measured total sputtering yields for impact of slow (less than or equal to 100 eV) singly and doubly charged ions on LiF. The minimum potential energy necessary to induce potential sputtering (PS ... [more ▼] We have measured total sputtering yields for impact of slow (less than or equal to 100 eV) singly and doubly charged ions on LiF. The minimum potential energy necessary to induce potential sputtering (PS) from UF was determined to be about 10 eV. This threshold coincides with the energy necessary to produce a cold hole in the valence band of LiF by resonant neutralization. This allows the first unambiguous identification of PS induced by cold holes. Further stepwise increase of the sputtering yield with higher projectile potential energies provides evidence for additional defect-mediated sputtering mechanisms operative in alkali halides. [less ▲] Detailed reference viewed: 97 (0 UL)![]() Ferring, Dieter ![]() in Zeitschrift für Entwicklungspsychologie und Padagogische Psychologie (1999), 31(3) Detailed reference viewed: 111 (2 UL)![]() Schulz, Christian ![]() in Mosella (1999), XXIV(1-2), 102-107 Detailed reference viewed: 78 (1 UL)![]() ; ; et al in EOS (1999), 80(11), 121-126 Detailed reference viewed: 138 (6 UL)![]() ![]() ; ; Ottersten, Björn ![]() in Signal Processing (1999), 79(1), 2944 Detailed reference viewed: 47 (0 UL)![]() ; ; Michels, Andreas ![]() in Journal of Research of the National Institute of Standards and Technology (1999), 104(3), 261-275 The paper presents a theoretical analysis of elastic magnetic small-angle neutron scattering (SANS) due to the nonuniform magnetic microstructure in nanocrystalline ferromagnets. The reaction of the ... [more ▼] The paper presents a theoretical analysis of elastic magnetic small-angle neutron scattering (SANS) due to the nonuniform magnetic microstructure in nanocrystalline ferromagnets. The reaction of the magnetization to the magnetocrystalline and magnetoelastic anisotropy fields is derived using the theory of micromagnetics. In the limit where the scattering volume is a single magnetic domain, and the magnetization is nearly aligned with the direction of the magnetic field, closed form solutions are given for the differential scattering cross-section as a function of the scattering vector and of the magnetic field. These expressions involve an anisotropy field scattering function, that depends only on the Fourier components of the anisotropy field microstructure, not on the applied field, and a micromagnetic response function for SANS, that can be computed from tabulated values of the materials parameters saturation magnetization and exchange stiffness constant or spin wave stiffness constant. Based on these results, it is suggested that the anisotropy field scattering function SH can be extracted from experimental SANS data. A sum rule for SH suggests measurement of the volumetric mean square anisotropy field. When magneto-crystalline anisotropy is dominant, then a mean grain size or the grain size distribution may be determined by analysis of SH. [less ▲] Detailed reference viewed: 96 (3 UL)![]() Hesse, Markus ![]() in Ökologisches Wirtschaften (1999), 14(5-6), 23-25 Detailed reference viewed: 125 (1 UL)![]() ![]() ; ; et al in Oncogene (1999), 18(25), 3742-53 Interleukin-6 (IL-6)-type cytokines lead to growth arrest of human A375 melanoma cells. The present study demonstrates that this effect depends on the activation of STAT transcription factors. We observed ... [more ▼] Interleukin-6 (IL-6)-type cytokines lead to growth arrest of human A375 melanoma cells. The present study demonstrates that this effect depends on the activation of STAT transcription factors. We observed a correlation between the extent of growth inhibition exerted by IL-6, IL-6 plus soluble IL-6 receptor or oncostatin M (OSM) and the intensities of STAT3 and STAT1 signals. A truncated chimeric receptor retaining only the membrane-proximal region of gp130, the common signal transducer of IL-6-type cytokines, did neither activate STATs nor mediate growth arrest of stable transfectants. These functions were restored by the addition of short STAT recruitment modules comprising critical tyrosine residues from gp130 (Y767, Y814). A receptor carrying tyrosine module Y759 of gp130 effectively mediated activation of the phosphatase SHP-2 but did not alter cell growth. Overexpression of dominant negative forms of STAT3 but not STAT1 abrogated the inhibitory effect of OSM and IL-6 in A375 cells. In addition, we have identified the cyclin-dependent kinase inhibitor p27/Kipl as a novel target to be regulated by IL-6-type cytokines. Stimulation-dependent upregulation of p27 mRNA occurred STAT3-dependently. Also p27 protein accumulated which coincided with the disappearance of hyperphosphorylated retinoblastoma protein in three human melanoma cell lines sensitive to IL-6-type cytokines. [less ▲] Detailed reference viewed: 108 (0 UL)![]() ![]() Ancel, Pascal ![]() in Revue Trimestrielle de Droit Civil (1999) Detailed reference viewed: 4558 (27 UL)![]() ![]() Friederich, Evelyne ![]() in The Journal of biological chemistry (1999), 274(38), 26751-60 Villin is an actin-binding protein of the intestinal brush border that bundles, nucleates, caps, and severs actin in a Ca(2+)-dependent manner in vitro. Villin induces the growth of microvilli in ... [more ▼] Villin is an actin-binding protein of the intestinal brush border that bundles, nucleates, caps, and severs actin in a Ca(2+)-dependent manner in vitro. Villin induces the growth of microvilli in transfected cells, an activity that requires a carboxyl-terminally located KKEK motif. By combining cell transfection and biochemical assays, we show that the capacity of villin to induce growth of microvilli in cells correlates with its ability to bundle F-actin in vitro but not with its nucleating activity. In agreement with its importance for microfilament bundling in cells, the KKEK motif of the carboxyl-terminal F-actin-binding site is crucial for bundling in vitro. In addition, substitutions of basic residues in a second site, located in the amino-terminal portion of villin, impaired its activity in cells and reduced its binding to F-actin in the absence of Ca(2+) as well as its bundling and severing activities in vitro. Altogether, these findings suggest that villin participates in the organization and stabilization of the brush border core bundle but does not initiate its assembly by nucleation of actin filaments. [less ▲] Detailed reference viewed: 56 (0 UL)![]() ![]() Schulz, Christian ![]() in Géographies. Bulletin de l'Association de Géographes Français (1999), 76(4), 397-407 Detailed reference viewed: 112 (2 UL)![]() ![]() ; ; Ottersten, Björn ![]() in IEEE Signal Processing Letters (1999), 6 Detailed reference viewed: 34 (0 UL)![]() ![]() ; Friederich, Evelyne ![]() in BioTechniques (1999), 26(3), 484-6488490 The concentration of proteins in cells is an important parameter that determines how a protein will interact with other proteins or pharmacological agents. Recent developments in Western blotting ... [more ▼] The concentration of proteins in cells is an important parameter that determines how a protein will interact with other proteins or pharmacological agents. Recent developments in Western blotting techniques have now made this a method of choice to measure protein concentration in complex solutions such as total cell extracts. We show that detection of Cy5-coupled secondary antibodies by PhosphorImager analysis produces signals that approach linearity with respect to protein concentration over a 20-fold range. We used this technique to estimate cellular levels of zyxin, which is an important protein component of the actin cytoskeleton in mammalian cells. By producing specific protein standards based on sequences that are available from public databases, it is now possible to estimate the concentration of almost any protein by this technique. [less ▲] Detailed reference viewed: 96 (0 UL)![]() ![]() Priem, Karin ![]() in Feministische Studien (1999), 17 Detailed reference viewed: 74 (0 UL)![]() ![]() Müller, Volker ![]() in Mathematics of Computation (1999), 68(226), 807-822 We present a sub-exponential algorithm for computing discrete logarithms in real quadratic congruence function fields of sufficiently large genus. We prove the correctness and the expected running time ... [more ▼] We present a sub-exponential algorithm for computing discrete logarithms in real quadratic congruence function fields of sufficiently large genus. We prove the correctness and the expected running time of the algorithm. The algorithm is a generalization of a similar algorithm for quadratic number fields. [less ▲] Detailed reference viewed: 107 (0 UL)![]() Schulz, Christian ![]() in Geographische Rundschau (1999) Detailed reference viewed: 87 (0 UL)![]() ; Lagerwall, Jan ![]() in Molecular Crystals and Liquid Crystals (1999), 351 Recent examinations on binary chiral-dopant antiferroelectric liquid crystalline mixtures revealed an unusual switching behaviour. In order to investigate the switching processes that take place in the ... [more ▼] Recent examinations on binary chiral-dopant antiferroelectric liquid crystalline mixtures revealed an unusual switching behaviour. In order to investigate the switching processes that take place in the mixtures, both in the bulk and as influenced by surfaces, further electrooptic and dielec- tric spectroscopy studies have been carried out on two model binary mix- tures in the induced SmA*, SmC* and SmCA* phases. The dielectric spectra feature the different modes typical for these phases, but of varying purity, indicating a more complex phase behaviour than expected. The electrooptic behaviour in the antiferroelectric phase varied from clearly antiferroelectric to near hysteresis-free switching directly between ferro- electric states. We conclude that the phase sequence, and consequently switching behaviour, is a function of both the type of dopant used and of the strength of the surface interactions (cell thickness). In thin cells syn- clinic (ferroelectric) ordering appears to be favoured. [less ▲] Detailed reference viewed: 128 (2 UL)![]() ![]() Priem, Karin ![]() in Pädagogische Rundschau (1999), 53 Detailed reference viewed: 196 (0 UL)![]() ![]() Schlichenmaier, Martin ![]() in Reports on Mathematical Physics (1999), 43 Detailed reference viewed: 49 (2 UL)![]() ![]() Krüger, Rejko ![]() in Journal of Neural Transmission (1999), 106(2), 159-63 Recently a mutation in the parking gene has been identified as the cause for an autosomal-recessively inherited form of early onset Parkinson's disease (EOPD). The disease causing minimal deletion has ... [more ▼] Recently a mutation in the parking gene has been identified as the cause for an autosomal-recessively inherited form of early onset Parkinson's disease (EOPD). The disease causing minimal deletion has been defined as a homozygous exon 4 loss in the parkin gene among Japanese patients. We investigated 140 sporadic and familial EOPD patients of German ancestry for the exon 4 deletion in the parkin gene. None of our patients exhibited a homozygous deletion of exon 4, suggesting a minor role of this mutation for EOPD in Caucasians. Nevertheless a detailed mutation analysis is warranted to explore the overall significance of mutations in the parkin gene in EOPD. [less ▲] Detailed reference viewed: 60 (1 UL)![]() Weber, Jean-Jacques ![]() in European English Messenger (1999), 8 Detailed reference viewed: 62 (0 UL)![]() ![]() Voos, Holger ![]() in Automatisierungstechnische Praxis (1999), 41(6), 48-54 This work introduces a new control concept for a re-winder in the spunweb production. The rewinder serves to cut the spunweb-rolls into several rolls of customer-specified width. High customer demands ... [more ▼] This work introduces a new control concept for a re-winder in the spunweb production. The rewinder serves to cut the spunweb-rolls into several rolls of customer-specified width. High customer demands toward roll quality were, so far, only met unsatisfactorily with PID control of the web-tension. The newly developed control concept uses fuzzy control. It provides a modular design and is specifically adjusted to the different states of the machine that occur during production. It was proven that this concept rapidly increases roll quality. The control concept is implemented on a PLC and used in industrial spunweb production at Freudenberg Vliesstoffe KG in Kaiserslautern. [less ▲] Detailed reference viewed: 68 (0 UL)![]() ![]() Cuniberti, Gilles ![]() in Recueil Dalloz (1999) Compétence internationale en matière de mesures conservatoires. Detailed reference viewed: 41 (0 UL)![]() ![]() ; ; et al in Genomics (1999), 62(1), 67-73 During the mouse ENU mutagenesis screen, mice were tested for the occurrence of dominant cataracts. One particular mutant was discovered as a progressive opacity (Po). Heterozygotes show opacification of ... [more ▼] During the mouse ENU mutagenesis screen, mice were tested for the occurrence of dominant cataracts. One particular mutant was discovered as a progressive opacity (Po). Heterozygotes show opacification of a superficial layer of the fetal nucleus, which progresses and finally forms a nuclear opacity. Since the homozygotes have already developed the total cataract at eye opening, the mode of inheritance is semidominant. Linkage analysis was performed using a set of genome-wide microsatellite markers. The mutation was mapped to chromosome 11 distal of the marker D11Mit242 (9.3 +/- 4.4 cM) and proximal to D11Mit36 (2.3 +/- 2.3 cM). This position makes the betaA3/A1-crystallin encoding gene Cryba1 an excellent candidate gene. Mouse Cryba1 was amplified from lens mRNA. Sequence analysis revealed a mutation of a T to an A at the second base of exon 6, leading to an exchange of Trp by Arg. Computer analysis predicts that the fourth Greek key motif of the affected betaA3/A1-crystallin will not be formed. Moreover, the mutation leads also to an additional splicing signal, to the skipping of the first 3 bp of exon 6, and finally to the deletion of the Trp residue. Both types of mRNA are present in the homozygous mutant lenses. The mutation will be referred to as Cryba1(po1). This particular mouse mutation provides an excellent animal model for a human congenital zonular cataract with suture opacities, which is caused by a mutation in the homologous gene. [less ▲] Detailed reference viewed: 65 (0 UL)![]() ![]() Ravarani, Georges ![]() in Feuilles de liaison de la Conférence Saint-Yves (1999), (88), 11 Detailed reference viewed: 48 (1 UL)![]() ![]() Tröhler, Daniel ![]() in Neue Pestalozzi-Blätter (1999), 5(1), 1-1 Detailed reference viewed: 34 (0 UL)![]() Wirtz, Ludger ![]() in Physical Review. B (1999), 59(4), 2956-2967 Within the semiclassical theory of magnetotransport through ballistic cavities, fluctuations in the transmission amplitude and in the conductance originate from the Aharonov-Bohm phase of directed areas ... [more ▼] Within the semiclassical theory of magnetotransport through ballistic cavities, fluctuations in the transmission amplitude and in the conductance originate from the Aharonov-Bohm phase of directed areas. We formulate the semiclassical transmission amplitude in gauge-invariant form. The gauge invariant phases can be visualized in terms of areas enclosed by classical paths, which consist of the real path connecting the entrance point to the exit point and a virtual path leading back to the entrance point. We implement this method on different levels of a semiclassical description of magnetotransport with applications to magnetoconductance fluctuations and correlations. The validity of the semiclassical theories is analyzed. [S0163-1829(99)10903-2]. [less ▲] Detailed reference viewed: 121 (1 UL)![]() Vögele, Claus ![]() in Verhaltensmodifikation und Verhaltensmedizin (1999), (20), 321-342 Psychophysiological experiments show large individual differences in physiological reactivity to mental stress. Hyperreactivity refers to the propensity for an individual to exhibit increased ... [more ▼] Psychophysiological experiments show large individual differences in physiological reactivity to mental stress. Hyperreactivity refers to the propensity for an individual to exhibit increased cardiovascular activity during exposure to external stimuli when compared to controls. Essential hypertensives show cardiovascular hyperreactivity that is not reflected in electrodermal or respiratory activity. This result indicates that cardiovascular reactivity could be an important component in the development of essential hypertension. This article provides an overview of conceptual issues and empirical findings concerning the role of cardiovascular reactivity and the development of essential hypertension. [less ▲] Detailed reference viewed: 94 (0 UL)![]() ![]() ; ; et al in EMBO Journal (1999), 18(19), 5205-15 Recently we demonstrated a strong induction of activin expression after skin injury, suggesting a function of this transforming growth factor-beta family member in wound repair. To test this possibility ... [more ▼] Recently we demonstrated a strong induction of activin expression after skin injury, suggesting a function of this transforming growth factor-beta family member in wound repair. To test this possibility, we generated transgenic mice that overexpress the activin betaA chain in the epidermis under the control of a keratin 14 promoter. The transgenic mice were significantly smaller than control littermates, and they had smaller ears and shorter tails. In their skin, the fatty tissue was replaced by connective tissue and a severe thickening of the epidermis was found. The spinous cell layer was significantly increased, and the epidermal architecture was highly disorganized. These histological abnormalities seem to result from increased proliferation of the basal keratinocytes and abnormalities in the program of keratinocyte differentiation. After skin injury, a significant enhancement of granulation tissue formation was detected in the activin-overexpressing mice, possibly as a result of premature induction of fibronectin and tenascin-C expression. These data reveal novel activities of activin in the regulation of keratinocyte proliferation and differentiation as well as in dermal fibrosis and cutaneous wound repair. [less ▲] Detailed reference viewed: 110 (0 UL)![]() ![]() ; ; et al in IEEE Transactions on Communications (1999), 47(1), 7888 Detailed reference viewed: 40 (0 UL)![]() Schiltz, Jang ![]() in Applied Mathematics & Optimization (1999), 39 In this paper we consider a nonlinear filtering problem with an unbounded observation coefficient, correlated noises, and a signal process driven by an infinite dimensional Brownian motion. We prove that ... [more ▼] In this paper we consider a nonlinear filtering problem with an unbounded observation coefficient, correlated noises, and a signal process driven by an infinite dimensional Brownian motion. We prove that the unnormalized filter admits a smooth density which is in the Schwartz space and we give a description of the support of the law of this density. [less ▲] Detailed reference viewed: 33 (2 UL)![]() Uhrmacher, Martin ![]() in Kurtrierisches Jahrbuch (1999), 39 Detailed reference viewed: 106 (0 UL)![]() ; ; et al in Molecular and Cellular Biochemistry (1999), 195(1-2), 11-7 The early growth response gene Egr-1 is a nuclear transcription factor known to serve as an intermediary in a broad range of signal transduction processes. Recent studies have assigned Egr-1 a new role as ... [more ▼] The early growth response gene Egr-1 is a nuclear transcription factor known to serve as an intermediary in a broad range of signal transduction processes. Recent studies have assigned Egr-1 a new role as an amplifier of gene expression. Egr-1 mRNA is expressed in the myocardium and is rapidly induced in response to hypertrophic stimuli. However, induction of the Egr-1 protein has not yet been demonstrated in the myocardium; on the other hand, in skeletal muscle cells we have shown translational regulation of Egr-1. To further investigate the role of Egr-1 in the regulatory mechanisms of a variety of signal transduction processes we have therefore asked whether bona fide hypertrophic stimuli induce Egr-1 protein subsequently to its mRNA in neonatal rat cardiomyocytes or whether translational block occurs. In confocal laser studies the Egr-1 protein was nuclearly localized. Norepinephrine (NE, 2 microM), angiotensin II (AII, 0.1 microM), and endothelin 1 (E1, 0.1 microM) each induced the Egr-1 mRNA 6-8 fold and the Egr-1 protein 3-5 fold (n = 3, p < 0.01). Therefore, in contrast to skeletal muscle cells, these stimuli increased Egr-1 mRNA and protein levels. These results point further to the role of Egr-1 as a possible amplifier of signal transduction in the myocardium. [less ▲] Detailed reference viewed: 66 (1 UL)![]() ![]() Wollscheid-Lengeling, Evi ![]() in Molecular Phylogenetics and Evolution (1999), 13(2), 215-226 This study investigated nudibranch phylogeny on the basis of 18S rDNA sequence data. 18S rDNA sequence data of 19 taxa representing the major living orders and families of the Nudibranchia were analyzed ... [more ▼] This study investigated nudibranch phylogeny on the basis of 18S rDNA sequence data. 18S rDNA sequence data of 19 taxa representing the major living orders and families of the Nudibranchia were analyzed. Representatives of the Cephalaspidea, Anaspidea, Gymnomorpha, Prosobranchia, and Pulmonata were also sequenced and used as outgroups. An additional 28 gastropod sequences taken from GenBank were also included in our analyses. Phylogenetic analyses of these more than 50 gastropod taxa provide strong evidence for support of the monophyly of the Nudibranchia. The monophyly of the Doridoidea, Cladobranchia, and Aeolidoidea within the Nudibranchia are also strongly supported. Phylogenetic utility and information content of the 18S rDNA sequences for Nudibranchia, and Opisthobranchia in general, are examined using the program SplitsTree as well as phylogenetic reconstructions using distance and parsimony approaches. 0Results based on these molecular data are compared with hypotheses about nudibranch phylogeny inferred from morphological data. [less ▲] Detailed reference viewed: 24 (0 UL)![]() Krüger, Jan-Kristian ![]() ![]() in Physical Review. B, Condensed Matter and Materials Physics (1999), 60(14), 10037-10041 Time-domain temperature-modulated differential scanning calorimetry and high-performance Brillouin spectroscopy have been used as experimental techniques in order to investigate the effect of the thermal ... [more ▼] Time-domain temperature-modulated differential scanning calorimetry and high-performance Brillouin spectroscopy have been used as experimental techniques in order to investigate the effect of the thermal glass transition on the specific heat as well as on the acoustic properties, quantities which are intimately related by thermodynamics, but measured at completely different frequencies. Using a siloxane as a model substance, we demonstrate the efficiency of hypersonic relaxations until thermal freezing of the material. Introducing the optoacoustic dispersion function as a sensitive measure for structural relaxations, we show that the high-frequency α relaxations are truncated by the thermal glass transition instead of dying out at much higher temperatures. Moreover, the extrapolated static compliance of the rubbery state goes to zero close to but below the thermal glass transition temperature Tg, indicating the existence of an acoustic instability which is reminiscent of the so-called Kauzmann paradox. [less ▲] Detailed reference viewed: 76 (0 UL)![]() ; ; et al in Electronics Letters (1999), 35(1999), 239-240 Vertical Si p-MOSFETs with channel lengths of 100nm were fabricated using selective low pressure chemical vapour deposition (LPCVD) epitaxial growth and conventional i-line lithography. The layout, called ... [more ▼] Vertical Si p-MOSFETs with channel lengths of 100nm were fabricated using selective low pressure chemical vapour deposition (LPCVD) epitaxial growth and conventional i-line lithography. The layout, called VOXFET, reduces gate to source/drain overlap capacitances, thus improving high speed applications. Transistors with a gate width of 12 um and gate oxide thickness of 10nm show transconductances gM of 200mS/mm and measured cutoff frequencies of fT = 8.7GHz and fMAX = 19.2 GHz. [less ▲] Detailed reference viewed: 139 (0 UL)![]() ; ; et al in Journal of Luminescence (1999), 80(1999), 133-136 Porous silicon reflection interference filters of Bragg type consists of up to 40 quarter wave layers with alternating high- and low-refraction index. The refraction index depends on the porosity of the ... [more ▼] Porous silicon reflection interference filters of Bragg type consists of up to 40 quarter wave layers with alternating high- and low-refraction index. The refraction index depends on the porosity of the silicon. The reflection wavelength can vary over a wide range and depends on the thickness and refraction index of the porous layers. A laterally continuously varying wavelength with linear profile of the filter can be achieved by manipulating the porosity and thickness of the silicon in the lateral direction. Our approach is to vary the Fermi level laterally by applying a potential parallel to the surface of the wafer. The slope of the Fermi level is easily controlled by the magnitude of the potential. The lateral current density and thus the porosity and thickness is related to the potential difference between the laterally varying Fermi level and the potential induced by the counter electrode. This relation is the well-known current-voltage characteristic of a Silicon hydrofluoric acid contact. The linearity of the etch profile across the wafer is demonstrated and the properties of preliminary reflection filters are shown. [less ▲] Detailed reference viewed: 88 (0 UL)![]() ![]() De Beaufort, Carine ![]() in Diabetologia (1999), 42(1), 51-55 The initiation of the immunopathogenetic process that can lead to Type I (insulin-dependent) diabetes mellitus in childhood probably occurs early in life. Studies in vitro have shown that vitamin D3 is ... [more ▼] The initiation of the immunopathogenetic process that can lead to Type I (insulin-dependent) diabetes mellitus in childhood probably occurs early in life. Studies in vitro have shown that vitamin D3 is immunosuppressive or immunomodulating and studies in experimental models of autoimmunity, including one for autoimmune diabetes, have shown vitamin D to be protective. Seven centres in Europe with access to population-based and validated case registers of insulin-dependent diabetes patients participated in a case-control study focusing on early exposures and risk of Type I diabetes. Altogether data from 820 patients and 2335 control subjects corresponding to 85% of eligible patients and 76% of eligible control subjects were analysed. Questions focused on perinatal events and early eating habits including vitamin D supplementation. The frequency of vitamin D supplementation in different countries varied from 47 to 97% among control subjects. Vitamin D supplementation was associated with a decreased risk of Type I diabetes without indication of heterogeneity. The Mantel-Haenszel combined odds ratio was 0.67 (95% confidence limits: 0.53, 0.86). Adjustment for the possible confounders: a low birth weight, a short duration of breast feeding, old maternal age and study centre in logistic regression analysis did not affect the significant protective effect of vitamin D. In conclusion, this large multicentre trial covering many different European settings consistently showed a protective effect of vitamin D supplementation in infancy. The findings indicate that activated vitamin D might contribute to immune modulation and thereby protect or arrest an ongoing immune process initiated in susceptible people by early environmental exposures. [less ▲] Detailed reference viewed: 72 (0 UL)![]() ![]() Hu, Adelheid ![]() in Zeitschrift für Fremdsprachenforschung (1999), 10(2), 277-303 Detailed reference viewed: 852 (3 UL)![]() ![]() ; ; et al in Developmental Biology (1999), 210(1), 15-29 During axial skeleton development, the notochord is essential for the induction of the sclerotome and for the subsequent differentiation of cartilage forming the vertebral bodies and intervertebral discs ... [more ▼] During axial skeleton development, the notochord is essential for the induction of the sclerotome and for the subsequent differentiation of cartilage forming the vertebral bodies and intervertebral discs. These functions are mainly mediated by the diffusible signaling molecule Sonic hedgehog. The products of the paired-box-containing Pax1 and the mesenchyme forkhead-1 (Mfh1) genes are expressed in the developing sclerotome and are essential for the normal development of the vertebral column. Here, we demonstrate that Mfh1 like Pax1 expression is dependent on Sonic hedgehog signals from the notochord, and Mfh1 and Pax1 act synergistically to generate the vertebral column. In Mfh1/Pax1 double mutants, dorsomedial structures of the vertebrae are missing, resulting in extreme spina bifida accompanied by subcutaneous myelomeningocoele, and the vertebral bodies and intervertebral discs are missing. The morphological defects in Mfh1/Pax1 double mutants strongly correlate with the reduction of the mitotic rate of sclerotome cells. Thus, both the Mfh1 and the Pax1 gene products cooperate to mediate Sonic hedgehog-dependent proliferation of sclerotome cells. [less ▲] Detailed reference viewed: 114 (0 UL)![]() Weber, Jean-Jacques ![]() in Social Semiotics (1999), 9 Detailed reference viewed: 117 (0 UL)![]() ![]() ; Balling, Rudi ![]() in Trends in Genetics (1999), 15(2), 59-65 Organs have to develop at precisely determined sites to ensure functionality of the whole organism. Organogenesis is typically regulated by a series of interactions between morphologically distinct ... [more ▼] Organs have to develop at precisely determined sites to ensure functionality of the whole organism. Organogenesis is typically regulated by a series of interactions between morphologically distinct tissues. The developing tooth of the mouse is an excellent model to study these processes and we are beginning to understand the networks regulating reciprocal tissue interactions at the molecular level. Synergistic and antagonistic effects of signaling molecules including FGFs and BMPs are recursively used to induce localized responses in the adjacent tissue layer (mesenchyme or epithelium). However, at different phases of odontogenesis these secreted growth factors have distinct effects and at the same time they are regulated by different upstream factors. The mesenchymal transcription factors Msx1 and Pax9 are initially regulated by epithelial FGFs and BMPs, but subsequently they function upstream of these signaling molecules. This cascade provides a molecular model by which reciprocal tissue interactions are controlled. [less ▲] Detailed reference viewed: 183 (0 UL)![]() ![]() ; ; Ottersten, Björn ![]() in IEEE Transactions on Signal Processing (1999), 47(4), 945956 Detailed reference viewed: 49 (0 UL)![]() ![]() ; ; Ottersten, Björn ![]() in IEEE Transactions on Communications (1999), 47(11), 16281631 Detailed reference viewed: 31 (0 UL)![]() ![]() Conac, Pierre-Henri ![]() in Bulletin Joly Bourse (1999), 6 Detailed reference viewed: 93 (1 UL)![]() Bisdorff, Raymond ![]() in Belgian Journal of Operations Research, Statistics and Computer Science (1999), 37(4), 379-387 In this paper we propose to apply the concept of L-valued kernels to the problem of constructing a global ranking from a pairwise L-valued outranking relation defined on a set of decision alternatives as ... [more ▼] In this paper we propose to apply the concept of L-valued kernels to the problem of constructing a global ranking from a pairwise L-valued outranking relation defined on a set of decision alternatives as encountered in the fuzzy preference modelling context. Our approach is based on a repetitive selection of best and worst candidates from sharpest L-valued or most credible initial and terminal kernels. A practical illustration will concern the global ranking of movies from individual evaluations of a given set of movie critics. [less ▲] Detailed reference viewed: 32 (1 UL)![]() ![]() Bisdorff, Raymond ![]() in European Journal of Operational Research (1999), 119(2), 379-387 Detailed reference viewed: 72 (1 UL)![]() ![]() Vlassis, Nikos ![]() in IEEE Transactions on Systems, Man and Cybernetics. Part A, Systems and Humans (1999), 29(4), 393-399 We address the problem of probability density function estimation using a Gaussian mixture model updated with the expectation-maximization (EM) algorithm. To deal with the case of an unknown number of ... [more ▼] We address the problem of probability density function estimation using a Gaussian mixture model updated with the expectation-maximization (EM) algorithm. To deal with the case of an unknown number of mixing kernels, we define a new measure for Gaussian mixtures, called total kurtosis, which is based on the weighted sample kurtoses of the kernels. This measure provides an indication of how well the Gaussian mixture fits the data. Then we propose a new dynamic algorithm for Gaussian mixture density estimation which monitors the total kurtosis at each step of the Ehl algorithm in order to decide dynamically on the correct number of kernels and possibly escape from local maxima. We show the potential of our technique in approximating unknown densities through a series of examples with several density estimation problems. [less ▲] Detailed reference viewed: 90 (1 UL)![]() ![]() ; Ottersten, Björn ![]() in IEEE Transactions on Signal Processing (1999), 47(12), 32203234 Detailed reference viewed: 36 (0 UL)![]() ![]() Hesse, Markus ![]() in Geographische Zeitschrift (1999), 87(3-4), 223-237 Detailed reference viewed: 118 (0 UL)![]() Uhrmacher, Martin ![]() in Kurtrierisches Jahrbuch (1999), 39 Detailed reference viewed: 110 (1 UL)![]() ![]() Biesta, Gert ![]() in Studies in Philosophy & Education (1999), 18(4), 203-220 Detailed reference viewed: 73 (0 UL)![]() ; Vögele, Claus ![]() in Psychotherapy & Psychosomatics (1999), 68 BACKGROUND: Binge eating behavior in bulimic patients is thought to play a crucial role in the regulation of psychophysiological arousal in stressful situations. Previous results suggest that ... [more ▼] BACKGROUND: Binge eating behavior in bulimic patients is thought to play a crucial role in the regulation of psychophysiological arousal in stressful situations. Previous results suggest that interpersonal stress and achievement challenge are perceived as particularly stressful by bulimic individuals. It is not clear, however, whether bulimic individuals respond to stress with an increased desire to binge, and whether this increase is accompanied by higher psychophysiological reactivity compared to healthy controls. METHODS: Twenty-seven patients with bulimia nervosa (DSM-IV), 27 restrained eaters, and 27 controls participated in two experimental sessions in which continuous measures of heart rate, blood pressure, respiration rat e, and ecectrodermal activity were monitored under conditions of achievement challenge (mental arithmetic, Stroop test) and interpersonal stress provoking feelings of loneliness and social rejection (film, imagery task). Ratings of desire to binge, negative mood, and hunger were obtained between experimental trials. Groups were matched for age and body mass index. RESULTS: There was a marked difference in subjective ratings during interpersonal stress. Bulimic patients responded to the imagery task with increases in both desire to binge and hunger, whereas restrained eaters and controls showed no change. There were no substantial group differences in psychophysiological reactivity. CONCLUSIONS: The dissociation between emotional responses and physiological activation may have important therapeutic implications. [less ▲] Detailed reference viewed: 153 (0 UL)![]() ![]() Ancel, Pascal ![]() in Revue Internationale de Droit Economique (1999), 2 Detailed reference viewed: 95 (6 UL)![]() Tröhler, Daniel ![]() in Infos und Akzente (1999), (1), 31-36 Detailed reference viewed: 104 (0 UL)![]() ![]() Mancuso, Giovanna ![]() in Psychopharmacology (1999), 142(1), 18-23 Fifteen 18- to 25-year-old male smokers were tested in a within-subjects design to determine the influence of a transdermal patch of 21 mg nicotine on vigilance. Subjects were tested on the RVIP test ... [more ▼] Fifteen 18- to 25-year-old male smokers were tested in a within-subjects design to determine the influence of a transdermal patch of 21 mg nicotine on vigilance. Subjects were tested on the RVIP test (Rapid Visual Information Processing test) 1.30, 3.00 and 6.30 h after patch application, to verify the involvement of the dose of nicotine on the performance. This study confirms and extends the increasing effects of nicotine on vigilance previously found with orally and transdermally given nicotine. Moreover, it showed that such performance was independent of the time of nicotine absorption (1.30, 3.00 and 6.30 h after patch application), which suggests that a relatively low dose of nicotine suffices to activate vigilance processing. Regarding motor performance, no convincing effect of nicotine was observed on reaction time. [less ▲] Detailed reference viewed: 101 (2 UL)![]() ![]() ; Bueb, Jean-Luc ![]() ![]() in European Journal of Pharmacology (1999), 361(2-3), 293-8 Store-operated Ca2+ entry is referred to a capacitative current activated by Ca2+ -stores depletion in various non-excitable cells. Neutrophil-like HL-60 cells responded to N-formyl-L-Methionyl-L-Leucyl-L ... [more ▼] Store-operated Ca2+ entry is referred to a capacitative current activated by Ca2+ -stores depletion in various non-excitable cells. Neutrophil-like HL-60 cells responded to N-formyl-L-Methionyl-L-Leucyl-L-Phenylalanine (fMLP) by an early O2- production preceded by a [Ca2+]i rise. Cell stimulation in the absence of extracellular Ca2+ resulted in a major reduction of [Ca2+]i rise and O2- production. A purported inhibitor of store-operated Ca2+ entry, SK&F 96365 (1-(beta-(3-(4-methoxy-phenyl)propoxyl)-4-methoxy-phenetyl)- 1H-imidazole hydrochloride), inhibited extracellular Ca2+ -dependent [Ca2+]i rise by 30% but did not alter O2- production. In conclusion, SK&F 96365 did not modify extracellular Ca2+ -dependent O2- production, despite a significant but limited reduction in fMLP-activated membrane Ca2+ fluxes which can be ascribed to store-operated Ca2+ entry. Furthermore, Ca2+ influx is necessary for a full induction and maintenance of the biological response. [less ▲] Detailed reference viewed: 124 (0 UL)![]() ![]() ; ; et al in Developmental Dynamics : An Official Publication of the American Association of Anatomists (1999), 216(3), 233-43 To define genes specifically expressed in cartilage and during chondrogenesis, we compared by differential display-polymerase chain reaction (DD-PCR) the mRNA populations of differentiated sternal ... [more ▼] To define genes specifically expressed in cartilage and during chondrogenesis, we compared by differential display-polymerase chain reaction (DD-PCR) the mRNA populations of differentiated sternal chondrocytes from chicken embryos with mRNA species modulated in vitro by retinoic acid (RA). Chondrocyte-specific gene expression is downregulated by RA, and PCR-amplified cDNAs from both untreated and RA-modulated cells were differentially displayed. Amplification products only from RNA of untreated chondrocytes were further analyzed, and a cDNA-fragment of the chondromodulin-I (ChM-I) mRNA was isolated. After obtaining full length cDNA clones, we have analyzed the mRNA expression patterns at different developmental stages by RNase protection assay and in situ hybridization. Analysis of different tissues and cartilage from 17-day-old chicken embryos showed ChM-I mRNA only in chondrocytes. During somitogenesis of the chicken embryo, ChM-I transcripts were detected in the notochord, the floor and the roof plate of the neural tube, and in cartilage precursor tissues such as the sclerotomes of the somites, the developing limbs, the pharyngeal arches, the otic vesicle, and the sclera. ChM-I continued to be expressed in differentiated cartilages derived from these tissues and also in noncartilaginous domains of the developing heart and retina. Thus, in the chicken, the expression of ChM-I is not restricted to mature cartilage but is already present during early development in precartilaginous tissues as well as in heart and eye. [less ▲] Detailed reference viewed: 103 (0 UL)![]() ![]() ; Kreis, Stephanie ![]() in Virus Research (1999), 62(1), 89-95 A comprehensive phylogenetic study based on the hemagglutinin (H) protein of all known African measles virus (MV) isolates is presented. The study includes 64 new H gene sequences from Ghana, Nigeria and ... [more ▼] A comprehensive phylogenetic study based on the hemagglutinin (H) protein of all known African measles virus (MV) isolates is presented. The study includes 64 new H gene sequences from Ghana, Nigeria and South Africa as well as viruses from Zambia and The Gambia for which only incomplete sequencing data were available and that have previously not been genotyped. The results provide further support to the tentative assignment of the Nigerian and Ghanaian viruses to a new genotype B3 within clade B. A distinct geographic distribution pattern emerged with clade B viruses circulating exclusively in African countries north of the equator. All MV strains from southern Africa grouped in clades A and D with the majority of viruses belonging to genotype D4. The viruses considerably differed by their sensitivity to neutralization by monoclonal antibodies (mAb), but three selected antibodies were sufficient to distinguish between African MVs representing four different genotypes. Copyright (C) 1999 Elsevier Science B.V. [less ▲] Detailed reference viewed: 117 (6 UL)![]() ![]() Tröhler, Daniel ![]() in Neue Pestalozzi-Blätter (1999), 5(2), 1-1 Detailed reference viewed: 38 (0 UL)![]() Leprévost, Franck ![]() in Journal of Number Theory (1999), 78 Detailed reference viewed: 45 (0 UL)![]() ![]() Hesse, Markus ![]() in Erdkunde (1999), 53(4), 317-329 Detailed reference viewed: 150 (1 UL)![]() Cuniberti, Gilles ![]() in Petites Affiches, la Loi (1999) Detailed reference viewed: 86 (0 UL)![]() Tröhler, Daniel ![]() in Neue Pestalozzi-Blätter (1999), 5(2), 31-33 Detailed reference viewed: 618 (3 UL)![]() ![]() Mancuso, Giovanna ![]() in Psychopharmacology (1999), 146(2), 199-204 RATIONALE: It is now well established from electrophysiological and behavioural evidence that nicotine has effects on information processing. The results are usually explained either by a primary effect ... [more ▼] RATIONALE: It is now well established from electrophysiological and behavioural evidence that nicotine has effects on information processing. The results are usually explained either by a primary effect of nicotine or by a reversal effect of a nicotine-induced, abstinence deficit. In addition, there is dispute about the cognitive processes underlying the changes in performance. METHODS: This study has approached the first question by using the nicotine patch, in order to administer nicotine chronically. In addition, we examined the effects of nicotine on attention with a selection of tests which assessed the intensity and selectivity features of attention, using the Random Letter Generation test, the Flexibility of Attention test and the Stroop test. RESULTS: Nicotine enhanced the speed of number generation and the speed of processing in both the control and interference conditions of the Stroop test. There were no effects on attentional switching of the Flexibility of Attention test. CONCLUSION: The results are consistent with the hypothesis that nicotine mainly improves the intensity feature of attention, rather than the selectivity feature. [less ▲] Detailed reference viewed: 96 (0 UL)![]() Hesse, Markus ![]() in Geographische Rundschau (1999), 51(10), 576-578 Detailed reference viewed: 101 (0 UL)![]() ![]() del Sol Mesa, Antonio ![]() in Journal of Mathematical Chemistry (1999) Detailed reference viewed: 57 (1 UL)![]() Schiltz, Jang ![]() in Portugaliae Matematicae (1999), 56 In this paper, we investigate a nonlinear ¯ltering problem with correlated noises, bounded coe±cients and a signal process evolving in an in¯nite dimensional space. We derive the Kushner{Stratonovich and ... [more ▼] In this paper, we investigate a nonlinear ¯ltering problem with correlated noises, bounded coe±cients and a signal process evolving in an in¯nite dimensional space. We derive the Kushner{Stratonovich and the Zakai equation for the associated ¯lter respectively unnormalized ¯lter. A robust form of the Zakai equation is established for an uncorrelated ¯ltering problem. [less ▲] Detailed reference viewed: 34 (1 UL)![]() ![]() Peters, Bernhard ![]() in Combustion and Flame (1999), 116(1-2), 297-301 Detailed reference viewed: 135 (1 UL)![]() ; ; et al in Electrochimica Acta (1999), 44(1999), 3821-3826 A bioelectronic interface based on the coupling of an intact insect antenna to a field-e effct transistor (FET) has been realised in a whole-beetle BioFET (Biologically sensitive FET) and an isolated ... [more ▼] A bioelectronic interface based on the coupling of an intact insect antenna to a field-e effct transistor (FET) has been realised in a whole-beetle BioFET (Biologically sensitive FET) and an isolated-antenna BioFET configuration. The intrinsic BioFET characteristics, such as current-voltage curves, transconductance and signal-to-noise ratio clearly depend on the chip layout. Therefore, the experiments were performed with three di erent gate geometries: linear shape (5 um x 100 um), U shape (5 um x 1000 um) and meander shape (10 um x 6000 um). The BioFET allows the determination of the `green-leaf odour' Z-3-hexen-l-ol down to the low ppb concentration range. Thus, the detection of plant damages is possible with this novel kind of biosensor. [less ▲] Detailed reference viewed: 95 (0 UL)![]() ![]() Roelens, Nathalie ![]() in Texte (numéro spécial "Mnémotechnologies. Texte et mémoire") (1999) Detailed reference viewed: 104 (1 UL)![]() Scuto, Denis ![]() in Galerie. Revue culturelle et pédagogique (1999), (17/1), 7-15 Detailed reference viewed: 62 (2 UL)![]() Sieburg, Heinz ![]() in SVMMA CUM PROBITATE. Mélanges offert à Jean-Paul Harpes par ses collègues et amis. Publications du Centre Universitaire du Luxembourg 199 (1999) Detailed reference viewed: 76 (2 UL)![]() ![]() Haan, Serge ![]() in Journal of Biological Chemistry (1999), 274(3), 1342-8 Signal transducers and activators of transcription (STATs) are important mediators of cytokine signal transduction. STAT factors are recruited to phosphotyrosine-containing motifs of activated receptor ... [more ▼] Signal transducers and activators of transcription (STATs) are important mediators of cytokine signal transduction. STAT factors are recruited to phosphotyrosine-containing motifs of activated receptor chains via their SH2 domains. The subsequent tyrosine phosphorylation of the STATs leads to their dissociation from the receptor, dimerization, and translocation to the nucleus. Here we describe the expression, purification, and refolding of the STAT3-SH2 domain. Proper folding of the isolated protein was proven by circular dichroism and fluorescence spectroscopy. The STAT3-SH2 domain undergoes a conformational change upon dimerization. Using an enzyme-linked immunosorbent assay we demonstrate that the monomeric domain binds to specific phosphotyrosine peptides. The specificity of binding to phosphotyrosine peptides was assayed with the tyrosine motif encompassing Tyr705 of STAT3 and with all tyrosine motifs present in the cytoplasmic tail of the signal transducer gp130. [less ▲] Detailed reference viewed: 104 (5 UL)![]() ![]() Roelens, Nathalie ![]() in Voir (1999) Detailed reference viewed: 56 (1 UL)![]() Leprévost, Franck ![]() in Journal für die Reine und Angewandte Mathematik (1999), 514 Detailed reference viewed: 47 (0 UL)![]() ![]() Peters, Bernhard ![]() in Industrial Heat Engineering (1999), 21 Detailed reference viewed: 136 (0 UL)![]() ![]() ; ; et al in Biochimica et Biophysica Acta (1999), 1440(2-3), 266-74 The presence of CB(2) receptors was reported in the rat basophilic cell line RBL-2H3 and N-palmitoylethanolamide was proposed as an endogenous, potent agonist of this receptor. We synthesized a series of ... [more ▼] The presence of CB(2) receptors was reported in the rat basophilic cell line RBL-2H3 and N-palmitoylethanolamide was proposed as an endogenous, potent agonist of this receptor. We synthesized a series of 10 N-palmitoylethanolamide homologues and analogues, varying by the elongation of the fatty acid chain from caproyl to stearoyl and by the nature of the amide substituent, respectively, and evaluated the affinity of these compounds to cannabinoid receptors in the rat spleen, RBL-2H3 cells and CHO-CB(1) and CHO-CB(2) receptor-transfected cells. In rat spleen slices, CB(2) receptors were the predominant form of the cannabinoid receptors. No binding of [(3)H]SR141716A was observed. [(3)H]CP-55,940 binding was displaced by WIN 55,212-2 and anandamide. No displacement of [(3)H]CP-55,940 or [(3)H]WIN 55,212-2 by palmitoylethanolamide derivatives was observed in rat spleen slices. In RBL-2H3 cells, no binding of [(3)H]CP-55,940 or [(3)H]WIN 55,212-2 could be observed and conversely, no inhibitory activity of N-palmitoylethanolamide derivatives and analogues was measurable. These compounds do not recognize the human CB(1) and CB(2) receptors expressed in CHO cells. In conclusion, N-palmitoylethanolamide was, in our preparations, a weak ligand while its synthesized homologues or analogues were essentially inactive. Therefore, it seems unlikely that N-palmitoylethanolamide is an endogenous agonist of the CB(2) receptors but it may be a compound with potential therapeutic applications since it may act via other mechanisms than cannabinoid CB(1)-CB(2) receptor interactions. [less ▲] Detailed reference viewed: 128 (0 UL)![]() ![]() ; Bueb, Jean-Luc ![]() ![]() in Cell Calcium (1999), 25(5), 381-9 The aim of our study was to investigate the physiologic mechanisms involved in eosinophil activation as an essential prerequisite to disrupting the biochemical cascade that triggers inflammation, thereby ... [more ▼] The aim of our study was to investigate the physiologic mechanisms involved in eosinophil activation as an essential prerequisite to disrupting the biochemical cascade that triggers inflammation, thereby attenuating the effect of this activation or, ideally, preventing it from occurring. We have, therefore, examined the nature of the fMLP- and PAF-induced [Ca2+]i rise and the relationship between the [Ca2+]i rise and O2- production in human umbilical cord blood-derived eosinophils cultured in the presence of IL-3 and IL-5. These cells responded to fMLP or PAF (1 microM each) with an increase in [Ca2+]i (217.3 +/- 22.1 and 197.8 +/- 22.1 nM respectively) which was associated with production of O2- (40.2 +/- 8.2 and 35.2 +/- 7.6 pmol/min/10(6) cells respectively). The role of Ca2+ in the induced respiratory burst was studied by changing the availability of Ca2+ in the intra- and extracellular compartments. Removal or chelation of extracellular Ca2+ induced a reduction of both the fMLP and PAF-induced [Ca2+]i rise and O2- production. Chelation of intracellular Ca2+ induced a concentration-dependent inhibition of fMLP- and PAF-induced [Ca2+]i rise and caused a decrease in O2- production. SK&F 96365 had a stimulatory effect on PAF-induced [Ca2+]i rise and on fMLP-induced O2- production, this phenomenon was not observed with extracellular Ca2+ removal or chelation. Furthermore, Ni2+ exhibited an inhibition of both fMLP and PAF-induced [Ca2+]i rise and O2- production. Finally, both fMLP and PAF induced an increase in divalent cation influx that was further augmented by thapsigargin. Our results indicate that fMLP and PAF dependent O2- production in human eosinophils require intra- and extracellular Ca2+ and that Ca2+ influx is necessary for optimal activation. [less ▲] Detailed reference viewed: 129 (0 UL)![]() ![]() ; ; Ottersten, Björn ![]() in IEEE Transactions on Signal Processing (1999), 47(8), 21282138 Detailed reference viewed: 63 (0 UL)![]() ; ; et al in Solid-State Electronics (1999), 43(1999), 529-535 A novel vertical MOSFET concept using selective epitaxial growth by low pressure chemical vapor deposition is proposed and the ®rst p-channel device characteristics measured are described. In contrast to ... [more ▼] A novel vertical MOSFET concept using selective epitaxial growth by low pressure chemical vapor deposition is proposed and the ®rst p-channel device characteristics measured are described. In contrast to other MOS technologies, the gate oxide is deposited before epitaxy, and therefore it exists before the channel region is grown. Compared to planar layouts, the vertical layout increases the packing density without the use of advanced lithography; the extent of the increase depends on application. Compared to other vertical transistors, this concept reduces overlap capacitance and o ers the possibility of three-dimensional integration. Vertical p channel MOSFETs with a channel length LG down to 130 nm and a gate oxide thickness dox down to 12 nm have been fabricated and yield a transconductance of 100 mS mm-1. [less ▲] Detailed reference viewed: 88 (0 UL)![]() Fehlen, Fernand ![]() in Cahiers du Centre Universitaire, série I.S.I.S (1999), 1997(3), 41-56 Detailed reference viewed: 76 (1 UL)![]() ![]() ; Voos, Holger ![]() in Automatisierungstechnik (1999), 47(4), 181-182 Detailed reference viewed: 57 (0 UL)![]() Krüger, Jan-Kristian ![]() in Nanostructured Materials (1999), 12(1), 519-522 The nature of the glass transition is still a matter of debate. We used temperature modulated DSC (TMDSC) and Brillouin spectroscopy ( BS ) to investigate the freezing behaviour of canonical glasses ... [more ▼] The nature of the glass transition is still a matter of debate. We used temperature modulated DSC (TMDSC) and Brillouin spectroscopy ( BS ) to investigate the freezing behaviour of canonical glasses ( salol and di-n-butyl-phtalate (DBP)) confined to controlled pore glasses (CPG) with pore diameters between 2.5 and 20 nm. The temperature behaviour of the heat capacity of the composite system deviates from the bulk fluid properties and we interpret the remaining kink-like anomaly at Tg as a static glass transition. In smaller pores Tg is only slightly shifted to lower temperatures. This operative Tg is in good agreement with sound velocity data showing a sharp kink at Tg. The working hypothesis of the existence of a static glass transition is supported by the fact that the -relaxation process disappears with decreasing pore diameter. [less ▲] Detailed reference viewed: 107 (1 UL)![]() Marso, Michel ![]() in IEEE Photonics Technology Letters (1999), 11 The optoelectronic dc and RF behavior of an InAlAs–InGaAs optically controlled field-effect transistor based on a high electron mobility transistor layer structure is investigated at 1.3- um wavelength ... [more ▼] The optoelectronic dc and RF behavior of an InAlAs–InGaAs optically controlled field-effect transistor based on a high electron mobility transistor layer structure is investigated at 1.3- um wavelength light. The device is backside-illuminated to increase the responsivity. A transistor with 0.3-u m gate length and an active area of 50 x 50 u m2 exhibits a responsivity of 235 A/W, at 11- W incident optical power. The photoconductive response is higher than for an metal–semiconductor–metal photodetector with the same InGaAs absorption layer thickness up to 10 GHz. [less ▲] Detailed reference viewed: 49 (0 UL)![]() Lagerwall, Jan ![]() in Ferroelectrics (1999), 244 In an attempt to determine the physical nature of the low-frequency dielectric mode in antiferroelectric liquid crystals, we have studied the dielectric response in thick planar-oriented samples of ... [more ▼] In an attempt to determine the physical nature of the low-frequency dielectric mode in antiferroelectric liquid crystals, we have studied the dielectric response in thick planar-oriented samples of Smectic C/sub A/* compounds undergoing a helix inversion. If the mode is collective there ought to be a minimum in the dielectric absorption due to the mode, at the temperature at which the helical pitch diverges. Although the effect is not large, we find minima for both antiferroelectric modes at this point, indicating that both modes are related to the helical director structure. A corresponding experiment has also been performed on a binary mixture which shows a helix inversion for a certain mixing ratio. However, because the effect in this case is overshadowed by unavoidable variations in other parameters, no minimum was detected. [less ▲] Detailed reference viewed: 131 (1 UL) |
||