Showing papers by "University of Luxembourg published in 1997"
TL;DR: It is hypothesised that existing 1D-3D threading methods essentially do not capture more than the fitness of an amino acid sequence for a particular 1D succession of secondary structure segments and residue solvent accessibility.
288 citations
TL;DR: The data show that replication in particular helps to reduce overall bandwidth as well as user-perceived latency, and can also provide a more fault-tolerant and evenly balanced system.
Abstract: The World Wide Web and the phrase 'traffic jam' have become as linked in the minds of many computer users as are the urban superhighway and rush hour to the early morning commuter. Insufficient bandwidth causing high latency are the order of the day. Caching is a standard solution for this type of problem, and it was applied to the Web early on for this reason. The more advanced approaches of replication and application level naming were introduced to further attack the problem. However, these complex methods could easily exacerbate the situation if the implementation is not well designed and the results are not evaluated carefully. This article examines the benefits that can be obtained from both caching and replication by analyzing the performance of the main proxy cache at the University of Kaiserslautern as well as a system of replicate servers designed and implemented at the University's System Software research group. Our data show that replication in particular helps to reduce overall bandwidth as well as user-perceived latency. It can also provide a more fault-tolerant and evenly balanced system.
147 citations
TL;DR: The hypothesis that the persistence of pain in many of the concerned patients may significantly be related to dysfunctional reciprocal relations between neural, endocrine and immune function is supported.
138 citations
TL;DR: Estrogen receptor-mediated effects on proliferation in skeletal myoblasts estrogen receptor was demonstrated by immunoblotting, immunofluorescence microscopy and transfection studies and Estrone induced a significant increase in myoblast growth whereas 17 beta-estradiol had no effect.
118 citations
TL;DR: An overview of the differences and currently deployed, developed, and evaluated solutions to the problem of network congestion in the World Wide Web is given.
Abstract: The Internet has fallen prey to its most successful service, the World Wide Web The networks do not keep up with the demands incurred by the huge amount of Web surfers Thus, it takes longer and longer to obtain the information one wants to access via the World Wide Web Many solutions to the problem of network congestion have been developed in distributed systems research in general and distributed file and database systems in particular The introduction of caching and replication strategies has proven to help in many situations; therefore, these techniques are also applied to the Web Although most problems and associated solutions are known, some circumstances are different with the Web, forcing the adaptation of known strategies This article gives an overview of these differences and currently deployed, developed, and evaluated solutions
103 citations
TL;DR: It is proposed that zyxin enhances actin organizing activity in mammalian cells in a manner similar to that which occurs with membrane-targeted ActA sequences.
Abstract: The intracellular bacterial parasite Listeria monocytogenes produces ActA protein at its surface to facilitate the localized assembly of actin-filled comets that are required for movement. The organization of actin in Listeria comets shows striking similarity to the organization of actin at the plasma membrane of mammalian cells. Therefore we examined the possibility that an ActA-like protein is present in mammalian cells. By using antibodies directed against ActA, we identified zyxin as an ActA related protein in a number of cell types. We compared the functions of ActA and zyxin by transient expression of variants tagged with an inner plasma membrane localization sequence (a CAAX box). Targeting of the proline rich domain of zyxin to the plasma membrane disrupts the actin cytoskeleton and cell shape in a manner similar to that which occurs with membrane-targeted ActA sequences. A chimeric protein composed of the N-terminal domain of ActA fused to the N-terminal and central domains of zyxin induced a full ActA response in cells. Furthermore, zyxin and ActA exhibit common protein partners in vitro. On the basis of the shared properties of zyxin and ActA, we propose that zyxin enhances actin organizing activity in mammalian cells.
98 citations
TL;DR: In this paper, the authors give a version of integration by parts on the level of local martingales, combined with the optional sampling theorem, which allows them to obtain differentiation formulae for Poisson integr...
Abstract: We give a version of integration by parts on the level of local martingales; combined with the optional sampling theorem, this method allows us to obtain differentiation formulae for Poisson integr...
67 citations
TL;DR: Comparison of the South African MV strains with those previously described revealed that at least two distinct groups of wild-type (wt) MV exist, one of which has been circulating since 1986 and the majority of South African isolates analysed here formed a new genotype.
Abstract: Sequence analysis was performed on 20 measles virus (MV) isolates from South Africa, five of which were obtained between 1986 and 1989 and 15 isolates collected during the 1994/95 measles season. A 590 bp fragment of the carboxyl terminus of the nucleocapsid (N) was amplified by PCR and subjected to sequence and phylogenetic analysis. Comparison of the South African MV strains with those previously described revealed that at least two distinct groups of wild-type (wt) MV exist, one of which has been circulating since 1986. The major genotype (I) was represented by the more recent isolates which showed three characteristic amino acid substitutions. Furthermore, three vaccine-like viruses with sequences very similar to the Edmonston wt strain were identified. Phylogenetic analysis of 100 MV strains allowed the assignment of new definitions for MV genotypes and subgroups. Employing these definitions, the majority of South African isolates analysed here formed a new genotype.
63 citations
TL;DR: Results suggest that the occurrence of delta mtDNA4834 in rat is related to oxidative stress, and a positive correlation between metabolic rate, GSHPx, and the deletion was found.
39 citations
TL;DR: It is shown that a receptor dimer with only a single STAT1 docking site was still able to lead to STAT1 activation, indicating that the formation of a paired set of STAT binding sites in a receptor complex is not the prerequisite for STAT factor dimerization.
37 citations
TL;DR: In this article, a fully crystalline, thermoreversible morphology in the ferroelectric copolymer poly[vinylidenefluoride-trifluoroethylene] was described.
Abstract: Highly crystalline and uniaxial-oriented polytetrafluoroethylene films, nanostructured in one dimension, were used to produce a fully crystalline, thermoreversible morphology in the ferroelectric copolymer poly[vinylidenefluoride-trifluoroethylene]. The resulting state is built up of regularly stacked lamellar crystals of about 100 nm thickness and lateral dimensions of about 6 \ensuremath{\mu}m.
TL;DR: GAD antibodies at clinical onset do not predict the rate of β-cell destruction in young children with newly diagnosed IDDM, and the highly variable GAD antibody levels suggest variation of the autoimmune process.
Abstract: OBJECTIVE To investigate whether the presence of GAD antibodies at onset of IDDM correlates to a more aggressive rate of β-cell destruction after clinical onset. RESEARCH DESIGN AND METHODS We studied GAD antibodies at onset of disease, after 1 year, and after 6 years in 33 consecutively referred children (mean age 8.08, range 1.7–16.3). In a subset of 11 patients, GAD antibodies were studied very frequently. The correlation between GAD antibodies and clinical parameters, including glycosylated hemoglobin, residual insulin secretion, and insulin dosage, was evaluated. RESULTS GAD antibody titers were highly variable. Four patients became GAD antibody positive weeks to years after clinical onset. Other patients switched between testing positive and negative for GAD antibodies shortly after clinical onset. No correlation was found between the presence of GAD antibodies and the rate of β-cell destruction, but patients with high GAD antibody indexes at onset had significantly higher glycosylated hemoglobin levels. CONCLUSIONS GAD antibodies at clinical onset do not predict the rate of β-cell destruction in young children with newly diagnosed IDDM. The highly variable GAD antibody levels suggest variation of the autoimmune process.
Book•
01 Jan 1997TL;DR: The high innervation density of the knee joint capsule by nerve fibres containing calcitonin gene-related peptide supports the hypothesis of an important regulatory function of this peptide in normal tissue.
Abstract: The knee joint of the cat has been used extensively to study the morphology and function of primary afferents in a deep somatic tissue. A proportion of these neurones synthesizes various neuropeptides, with calcitonin gene-related peptide being the most prominent. In the present study we examined the distribution and density of nerve fibres immunoreactive for calcitonin gene-related peptide within the medial articular capsule. The fibres were predominantly located in the superficial layer of the capsule. They formed a dense innervation pattern, mainly accompanying blood vessels. Electron microscopy showed that most fibres were in close proximity to small arteries. The highest innervation density was found in parts of the capsule that were located over the epicondyle of the femur with 21±12 fibres per mm2 (mean±SD). In the tissue over the joint cleft this density was lower, with 11±6 fibres per mm2. In conclusion, the high innervation density of the knee joint capsule by nerve fibres containing calcitonin gene-related peptide supports the hypothesis of an important regulatory function of this peptide in normal tissue.
TL;DR: CGRP- and SP-like immunoreactivity (LI) coexisted in the spermatic nerve trunk and in the single fibers running along the surface of the testis, which are consistent with previous observations on testicular dorsal root ganglion neurons.
01 Jan 1997
01 Jan 1997
Book•
01 Jan 1997TL;DR: This work focuses on how actin can be used to generate a vectorial force that is required for cell movement, and identifies zyxin, a human protein that shares important structural and possibly functional properties with ActA, an actin dependent force generating protein of Listeria.
TL;DR: In this article, the DC and RF performance of HEMTs based on the Al-free material system InP/InGaAs/InP was investigated and the influence of gate length and channel composition on the performance of these devices was investigated.
Abstract: We report on the DC and RF performance of HEMTs based on the Al-free material system InP/InGaAs/InP. These structures were grown by LP-MOCVD using a nitrogen carrier. The influence of gate length and channel composition on the performance of these devices is investigated. We demonstrate that optimum DC and RF performance using highly strained channels can be obtained only if additional composite channels are grown. The cutoff frequencies f/sub T/=160 GHz and f/sub max/=260 GHz for a 0.1-/spl mu/m T-gate device indicate the suitability of our devices for W-band applications.
01 Jan 1997
01 Jan 1997
01 Jan 1997
Journal Article•
TL;DR: In this paper, the elastic constants of KPF6 have been determined in cubic and monoclinic phases, with two-phase coexistence regions in between, and elastic constants for c 44 and c 12 have been obtained.
Abstract: Potassium hexafluorophosphate KPF6 has been investigated by X-ray powder diffraction, calorimetry and Brillouin spectroscopy. With decreasing temperature, the crystal shows a sequence of phases: NaCl-type cubic-monoclinic-monoclinic with two-phase coexistence regions in between. In the cubic phase the elastic constants have been determined. c 44 and c 12 show a slight softening.
Journal Article•
01 Jan 1997
01 Jan 1997