Showing papers by "University of Luxembourg published in 1995"

Exploring the Mycoplasma capricolum genome: a minimal cell reveals its physiology.

Abstract: We report on the analysis of 214kb of the parasitic eubacterium Mycoplasma capricolum sequenced by genomic walking techniques. The 287 putative proteins detected to date represent about half of the estimated total number of 500 predicted for this organism. A large fraction of these (75%) can be assigned a likely function as a result of similarity searches. Several important features of the functional organization of this small genome are already apparent. Among these are (i) the expected relatively large number of enzymes involved in metabolic transport and activation, for efficient use of host cell nutrients; (ii) the presence of anabolic enzymes; (iii) the unexpected diversity of enzymes involved in DNA replication and repair; and (iv) a sizeable number of orthologues (82 so far) in Escherichia coli. This survey is beginning to provide a detailed view of how M. capricolum manages to maintain essential cellular processes with a genome much smaller than that of its bacterial relatives.

Calcitonin gene related peptide released from dural nerve fibers mediates increase of meningeal blood flow in the rat

Abstract: The parietal dura mater encephali of the rat was shown by immunohistochemistry to be densely innervated by calcitonin gene related peptide (CGRP) immunoreactive nerve fibers spreading around the me...

Sugawara Construction and Casimir Operators for Krichever-Novikov Algebras

Abstract: We show how to obtain from highest weight representations of Krichever-Novikov algebras of affine type (also called higher genus affine Kac-Moody algebras) representations of centrally extended Krichever-Novikov vector field algebras via the Sugawara construction. This generalizes classical results where one obtains representations of the Virasoro algebra. Relations between the weights of the corresponding representations are given and Casimir operators are constructed. In an appendix the Sugawara construction for the multi-point situation is done.

Urban space and logistics: on the road to sustainability?

Abstract: This paper deals with the interrelation of urban development, urban construction and commercial transport (goods movement, service industry) in towns, based on the research project "Sustainable Commercial Traffic" in the cities of Wuppertal, Solingen, Remschied (Germany) and other current German and Swiss activities. The project focused not only on steps for an integration of freight transport into urban transport planning but investigated also the different interests of urban planning and construction on the one hand and the companies on the other. To discuss problems and to moderate diverse interests between the operatives, a "Regional Freight Traffic Round Table" has been established. Concludes better communication is an important prerequisite for a sustainable transport development.

Development, patterns and causes of violence against foreigners in Germany: Social and biographical characteristics of perpetrators and the process of escalation

Abstract: Acts of violence against foreigners have increased dramatically since 1991 in Germany. The author underlines the wave‐like process of escalation and tries to identify triggering and amplifying factors (police reaction, political deficits, public opinion). He analyses police data concerning biographical and socio‐demographic characteristics of the perpetrators and discusses some of the prominent scientific interpretations (disintegration, individualisation, right‐wing activities) concerning the recent waves of right‐wing and xenophobic violence in Germany.

Jacobiennes de certaines courbes de genre $2$ : torsion et simplicité

Abstract: © Université Bordeaux 1, 1995, tous droits réservés. L’accès aux archives de la revue « Journal de Théorie des Nombres de Bordeaux » (http://jtnb.cedram.org/) implique l’accord avec les conditions générales d’utilisation (http://www.numdam.org/conditions). Toute utilisation commerciale ou impression systématique est constitutive d’une infraction pénale. Toute copie ou impression de ce fichier doit contenir la présente mention de copyright.

Hormonal induction of an immediate-early gene response in myogenic cell lines--a paradigm for heart growth.

Abstract: Cardiac hypertrophy is characterized by growth of myocardial cells without proliferation. Many endo- paracrine stimuli such as angiotensin II, endothelin, aradrenergic agonists, and insulin have been shown to be able to induce cardiac hypertrophy either in vivo or in vitro. We have used the myoblast model of differentiation and proliferation to determine nuclear signal transduction mechanisms in muscle and (by analogy) cardiac growth. The first nuclear event known to occur when a growth stimulus acts upon a cell is induction of a family of immediate-early genes. Our group focused on the role of one of these genes, the early growth response gene-1 (Egr-1). We have shown that this gene is induced in isolated adult cardiac myocytes in the presence of endothelin. An anti-sense oligonucleotide complementary to the first six codons of the Egr-1 mRNA abolishes the stimulation of protein synthesis induced by endothelin. In the present study we further characterized paracrine growth stimuli in the myogenic cell line Sol8, which was used as a paradigm to further investigate mechanisms of paracrine growth induction. We demonstrated that a variety of candidate endo- paracrine stimuli for the induction of cardiac hypertrophy induced the Egr-1 messenger RNA in the myogenic cell line Sol8. Among these are endothelin, insulin, basic fibroblast growth factor, and platelet-derived growth factor BB (PDGE BB). We conclude: (1) In analogy to the myocardium, these growth factors act upon myoblasts. (2) This line appears to be a suitable model for the molecular characterization of Egr-1 target genes.

Twentieth-Century Fiction: From Text to Context

Abstract: By applying recent trends in literary and language theory to a range of 20th Century fiction, the contributors to this text make new theoretical insights available to student readers. The analytical and interpretive strategies examined in this book are not intended to be prescriptive, rather they are presented in such a way as to facilitate critical reading and evaluation. The essays, which are arranged into three groups and which focus on the textual level, narrative and context, look at a wide range of Twentieth Century authors including Fowles, Foster, Lessing and Woolf. In addition, this student-friendly text includes a detailed subject index, a full glossary and helpful suggestions for further reading. Aimed at beginning students of English Language and Literature and Applied Linguistics, and advanced students of English as a Foreign or Second Language, 20th Century Fiction provides an essential introduction to the subject which is both sensitive and enabling.

Somatostatin-like immunoreactivity in primary afferents of the medial articular nerve and colocalization with substance P in the cat

Abstract: The proportion of somatostatin-containing dorsal root ganglion cells innervating the knee joint of the cat via the medial articular nerve was determined by using retrograde labeling with fast blue and immunohistochemistry. Immunoreactivity was found in 8.6% of labeled cell bodies. In colchicine-treated ganglia, the proportion increased to 16.8%. Only small and intermediate-sized perikarya showed somatostatin-like immunoreactivity, indicating that this neuropeptide is synthesized predominantly in primary afferent units with unmyelinated sensory axons but may also be present in primary afferents with thinly myelinated sensory fibers. Colchicine treatment had no influence on the cell size distribution. Colocalization of somatostatin with substance P was determined by comparing the proportions of immunopositive dorsal root ganglion cells after incubation with antibodies against substance P or somatostatin or with a mixture of both. Substance P-like immunoreactivity was found in 18.1% (untreated ganglia) and 19.6% (colchicine treated ganglia) of the labeled neurons. After incubation with a mixed antibody solution, 18.2% of joint afferents in untreated and 19.9% of the cells in colchicine-treated ganglia were immunopositive. Comparing this result with the results obtained using somatostatin and substance P antibodies alone, one can calculate that both neuropeptides are colocalized in about 17% of the cat's knee joint afferents. About 3% of the neurons contain only substance P, whereas almost none of the neurons contain only somatostatin. Based on this fact, one can assume that both neuropeptides are coreleased in peripheral tissue as well as in the central nervous system. © 1995 Wiley-Liss, Inc.

Second-order elasticity of liquid crystals within their nematic state at high frequencies

Abstract: Within this work we present Brillouin and ultrasonic investigations performed on the liquid crystals p-methoxybenzylidene p-(n-butylaniline) (MBBA), p-azoxyanisol (PAA), 4-cyano-4-n-alkylbiphenyles (nCB), and 4-n-pentoxybenzylidene-4'-n-octoaniline (5O.8). Special attention has been paid to the evolution of a significant splitting of the two longitudinal polarized acoustic modes within the nematic phase. Angle-resolving Brillouin spectroscopy allowed the determination of the complete stiffness tensors and hence a discussion of the propagation of quasitransverse polarized acoustic modes in the nematic state of liquid crystals. We analyze the behavior of the eigenvectors of the relevant acoustic modes and discuss their significance for the propagation of quasishear modes. For 5O.8 we report an acoustic instability within its nematic state. We confirm the existence of a universal thermal relaxation mechanism of weak activation energy for the nematic state of classical liquid crystals. The observed hypersonic anisotropy is discussed in terms of that relaxation mechanism and is compared with that of glass-forming liquid crystals.

Produktivitätslücken, Konvergenzprozesse und die Rolle der Wirtschaftsordnung: Anmerkungen zur „Catching up“-Hypothese

Abstract: Die Betrachtung langfristiger ökonomischer Entwicklungsmuster stellt eine markante Schnittstelle wirtschaftstheoretischer und wirtschaftshistorischer Analysen dar. Es ist daher nicht erstaunlich, daß gerade die Interpretation historischer Wachstumsverläufe immer wieder Kontroversen über die Theorien entstehen läßt, mit denen wirtschaftliches Wachstum und seine Determinanten adäquat erfaßt werden. Ein prominentes Beispiel dafür bietet die Diskussion um die Ursachen des bundesdeutschen "Wirtschaftswunders". In ihrer ausfuhrlichen Studie über das "verblassende Wunder" betonen Giersch, Paqué und Schmieding (1992) den engen Zusammenhang zwischen der bundesdeutschen Wirtschaftsordnung, ihren Veränderungen und der jeweiligen Wirtschaftsentwicklung. In einer Besprechung dieses Buches stellt Dombusch (1993) diese Sichtweise in Frage. Die langfristige Entwicklung in der Bundesrepublik unterscheide sich in ihrer Grundstruktur nur wenig von derjenigen in anderen westlichen Industriestaaten, die aber doch zum Teil ganz andere Wirtschaftsordnungen aufweisen. "The authors want us to believe that superior performance in the early period is due to free market economics and poor performance later to a lack thereof. But it is doubtful that free market economics has really been that important in the case of Germany. In fact, Germany does not really differ that much from the experience of a large group of countries." (Dornbusch, 1993, 884).

Lange Wellen“ der Unternehmenskonjunktur: Eine Untersuchung langfristiger Umsatz- und Innovationszyklen der Druckmaschinenfabrik Koenig & Bauer in Würzburg (1817-1992)

Abstract: The article deals with "long swings" in business activity and innovative behavior of Koenig & Bauer AG, Wuerzburg, the world's oldest producer of printing machines and still one of the most important competitors in this particular market. It is shown that quantitative indicators of sales and innovations since the firm's foundation in 1817 follow the general pattern of long cycles in economic activity proposed by Kondratieff, Schumpetr and others. A qualitative analysis reveals how the invention of the printing machine by Friedrich Koenig, the foundation of the firm and important episodes in the firm's history can be related to theories of innovation and technological change, which may be regarded as important contributions to a general theory of long swings. „Krisen gehören ebenso zur Geschichte eines traditionsreichen Unternehmens wie große Erfolge in technischer und kommerzieller Hinsicht." ( Koenig & Bauer AG, 175 Jahre Koenig & Bauer, Würzburg 1992, S. 51)

Molecular adaptation of the heart to hypertension

Abstract: Because myocardial hypertrophy is an independent risk factor for sudden death and cardiac failure, it is important to understand its molecular mechanisms to be able to devise new treatment strategies in the future. Stretch is the putative primary stimulus triggering hypertrophy. Further signal transduction steps such as auto- and paracrine secretion of growth factors or transmission via the cytoskeleton are beginning to be unravelled. Subsequent to hypertrophic stimuli some important proteins undergo an isoform switch; questitatively, however, the most important step is an increase in translational capacity for each mRNA. Myocardial specific gene expression is achieved by coordinate interaction of several transcription factors, some of which may be involved in nuclear transmission of hypertrophic signals. One of the genes capable of transmitting hypertrophic signals is the "early growth response gene-1 (Egr-1)". We have also shown that nuclear estrogen receptors act as transcription factors in the myocardium and may therefore be involved in the sex-specific modulation of cardiac hypertrophy. At present, pharmacological interventions aiming at reduction of hypertrophy by interfering with the signal transduction pathway from the membrane to the nucleus are actively being sought. These transduction pathways are composed of a series of proteinkinases which may be amenable to drugs. In the future, gene transfer may become an option for treatment.