547 research outputs found
Entwicklung einer schnellen Pulsformanalyse für asymmetrische AGATA-Germanium-Detektoren
No full textOnTEAM metadata: GDSID: DOC-2007-May-32; Attribute ID: LIBRARY-thesis_diss-2007-005; Title: [GSI Diss 2007-05] Entwicklung einer schnellen Pulsformanalyse für asymmetrische AGATA-Germanium-Detektoren; Author(s): Beck, Torsten; Corporate author(s): ; Publication date: 20070501; Creator: manton; Creation date: 15.05.2007 16:02:12; Change date: 29.10.2008 16:29:34; Access: nur berechtigte Gruppen; Attribute type: Text.Thesis.Diss; Directory path: ['GSI Publications', 'GSI as Publisher']; Attribute path: ['Infrastructure', 'Library and Documentation', 'thesis_diss', 'Added in 2007']; File name(s): ['DOC-2007-May-32-1.pdf']; File title(s): ['']; File access: ['nur berechtigte Gruppen'
Manifolds, sheaves, and cohomology
No full textThis book explains techniques that are essential in almost all branches of modern geometry such as algebraic geometry, complex geometry, or non-archimedian geometry. It uses the most accessible case, real and complex manifolds, as a model. The author especially emphasizes the difference between local and global questions. Cohomology theory of sheaves is introduced and its usage is illustrated by many examples. Content Topological Preliminaries - Algebraic Topological Preliminaries - Sheaves - Manifolds - Local Theory of Manifolds - Lie Groups - Torsors and Non-abelian Cech Cohomology - Bundles - Soft Sheaves - Cohomology of Complexes of Sheaves - Cohomology of Sheaves of Locally Constant Functions - Appendix: Basic Topology, The Language of Categories, Basic Algebra, Homological Algebra, Local Analysis Readership Graduate Students in Mathematics / Master of Science in Mathematics About the Author Prof. Dr. Torsten Wedhorn, Department of Mathematics, Technische Universität Darmstadt, Germany
James Watson, Maclyn McCarty, and Torsten Wiesel
No full textTorsten Wiesel (right) with Professor Emeritus Maclyn McCarty (center), co-author of the paper with Oswald Avery and Colin MacLeod, and James D. Watson, director of Cold Spring Harbor Laboratory, 1994
Photo by Leif Carlsson
To commemorate the fiftieth anniversary of the discovery at The Rockefeller University that genes are made of DNA - considered by many to be the single most important biological discovery of the twentieth century - the university has kicked off a year-long series of events that were running through May 1994. The celebration was formally inaugurated in November 1993 with a lecture by Nobel laureate James D. Watson, best known for discovering the double-helical structure of DNA.
See also Search Winter 1994, vol. 4, no. 1https://digitalcommons.rockefeller.edu/group-portraits/1013/thumbnail.jp
Seltsame Schauspiele. Torsten Fogelqvists Deutschlandreise 1934
No full textIn 1934 Torsten Fogelqvist, a prominent member of the Swedish Academy and a well-known journalist and intellectual, visits Nazi Germany. He writes about his visit to the Third Reich in 17 articles published in the Stockholm daily newspaper Dagens Nyheter. The author, highly critical of the Hitler regime, scrutinizes several aspects of the nazified German society such as the attempts to re-educate the German citizen in accordance with the ideology of the new regime, the hero cult in the Nazi movement, and the relationship between the German state and the churches. In order to further an understanding of political and social developments in Germany Fogelqvist uses a specific strategy. He “translates” them into an imaginary Swedish context. This paper compares his views with those of other Swedish visitors
Pathogenicity of Helicobacter hepaticus : genomic and functional aspects
No full textHelicobacter hepaticus stellt den Prototyp der enterohepatischen Helicobacter dar und führt zu einer persistenten Infektion von Mäusen. In immundefizienten Tieren kann er eine chronische Entzündung des Darmtraktes auslösen, welche den chronisch entzündlichen Darmerkrankungen des Menschen, Morbus Crohn und Colitis Ulcerosa, ähnelt. Deshalb wird H. hepaticus bevorzugt als Modellorganismus zur Untersuchung der immunologischen Ursachen von chronisch entzündlichen Darmerkrankungen im Tiermodell eingesetzt. Ebenfalls kann eine Infektion mit H. hepaticus in suszeptiblen Mäusestämmen (z.B. Balb/c, C3H/An) zu Entzündungen der Leber und Gallengänge führen, welche sich bis zu einer Hepatitis und Leberkarzinomen ausweiten können. In den meisten Studien wurde H. hepaticus bisher aber hauptsächlich als Auslöser dieser Erkrankungen eingesetzt, während die bakterielle Seite kaum betrachtet wurde. Im Rahmen dieser Arbeit wurde in einer Kooperation mit MWG Biotech, GeneData und dem Massachusetts Institute of Technology (MIT) die Gesamtgenomsequenz des H. hepaticus Referenzstammes ATCC 51449 bestimmt und annotiert. Das Genom hat eine Größe von 1.799.146 bp und kodiert für 1.875 Proteine. Die globale Ähnlichkeit des Genoms von H. hepaticus ist etwa gleich groß zu den sequenzierten Genomen von H. pylori und C. jejuni. Es fehlen H. hepaticus aber die meisten Virulenzfaktoren von H. pylori wie Adhäsine (SabA, BabA, AlpA), VacA und die meisten Proteine der cag-Pathogenitätsinsel, während Homologe zu Pathogenitätsfaktoren von C. jejuni wie CDT und Peb1 vorhanden sind. Das Genom von H. hepaticus enthält neben vielen kleineren genomischen Inseln eine Genominsel mit einer Größe von 71 kb, welche als HHGI1 benannt wurde. Sie kodiert mutmaßlich für ein TypIV-Sekretionssystem und enthält weitere Virulenzfaktoren. In Microarray- basierten Gesamtgenomvergleichen konnte gezeigt werden, dass die Insel in sieben von 13 untersuchten Stämmen großteils oder komplett fehlt. Während Mäuse, aus denen HHGI1-positive Stämme isoliert wurden, pathologische Veränderungen der Leber aufwiesen, wies keine von den Mäusen, aus denen HHGI1-negative Stämme isoliert wurden, Auffälligkeiten in der Leber oder dem Gallentrakt auf. In einem Tiermodell wurde in Kooperation mit dem MIT gezeigt, dass zwei Insel-negative Stämme zu einer geringeren Besiedlung und einer schwächeren Entzündung der Leber als der Insel-positive Referenzstamm ATCC 51449 führen. Durch die Genomvergleiche konnte auch gezeigt werden, dass verschiedene H. hepaticus-Stämme trotz einer niedrigen Sequenzvariabilität eine hohe Variation des Genomgehalts aufweisen und dass neben der HHGI1-Insel weitere kleinere Inseln in einzelnen Stämmen fehlen. Es wurden in der vorliegenden Arbeit erstmals verschiedene isogene Mutanten von H. hepaticus in der HHGI-1-Insel hergestellt, die in vitro eine verringerte Immunstimulation in Makrophagen zeigten. Der Mechanismus dieser Immunsuppression konnte noch nicht vollständig aufgeklärt werden, sie werden jedoch derzeit in Mausmodellen weiter auf ihre krankheitsauslösenden Eigenschaften untersucht. Da bisher keine gut charakterisierten Zellkulturmodelle für die in vitro-Untersuchung von H. hepaticus vorlagen, wurden solche im Rahmen dieser Arbeit etabliert. Dazu wurden die intestinale murine epitheliale Zelllinie m-ICcl2, welche das primäre Habitat von H. hepaticus (Krypten im Dünndarm) imitiert, die murine Hepatozytenzelllinie NCTC Klon 1469, welche ein mögliches sekundäres Habitat (Lebercanaliculi) imitiert und die murine Makrophagenzelllinie J774 benutzt. Während J774 und NCTC Klon 1469 durch die meisten Liganden für Mustererkennungsrezeptoren stimuliert werden konnten, reagierten m-ICcl2- Zellen substantiell nur auf den TLR4-Liganden E. coli-LPS. Dementsprechend induzierte H. hepaticus in J774 und NCTC Klon 1469 eine starke proinflammatorische Antwort, während m-ICcl2 trotz guter Adhärenz nur schwach von H. hepaticus stimuliert wurde. Es wurde gezeigt, dass LPS und Flagelline von H. hepaticus nur eine geringe immunstimulatorische Wirkung besitzen, während Lipoproteine und vermutlich auch Peptidoglykan die wichtigsten PAMPs von H. hepaticus darstellen. Durch die Analyse der durch H. hepaticus ausgelösten globalen Genregulation in J774 und NCTC Klon 1469 wurde nachgewiesen, dass H. hepaticus nicht primär über NF-κB, sondern über MAP-Kinasen eine proinflammatorische Antwort auslöst. Außerdem wurde gezeigt, dass H. hepaticus untypisch für extrazelluläre Bakterien eher eine Wirtsantwort auslöst, welche der durch intrazelluläre Bakterien ähnelt. In diesen Modellen führten HHGI1-negative Stämme oder Mutanten der HHGI1-Insel zu einer leicht verringerten proinflammatorischen Antwort. Dies spiegelte sich auch in der transkriptionellen Regulation von Schlüsselfaktoren der angeborenen Immunantwort wie TLR2, IL-12, NOD2 oder Tollip wieder. In m-ICcl2-Zellen führte eine Koinkubation mit lebenden H. hepaticus oder Lysaten zu einer verringerten durch E. coli-LPS ausgelösten Induktion von MIP-2. Darauf basierend wurde gezeigt, dass LPS von H. hepaticus einen wesentlichen Faktor für diese Inhibierung der proinflammatorischen Antwort darstellt, nicht jedoch die HHGI-1-Insel oder andere vermutete Virulenzfaktoren. Zumindest auf mRNA-Ebene wurde durch H. hepaticus auch die Induktion anderer Cytokine wie TNF-α oder MIP-1α gehemmt. Eine primäre Koinkubation von m-ICcl2 mit E. coli-LPS führte zu einer Toleranzinduktion gegenüber einer zweiten Stimulation. Diese Toleranzinduktion wurde durch eine Inkubation mit H. hepaticus ebenfalls gehemmt. Die Hemmung der proinflammatorischen Antwort durch H. hepaticus-LPS konnte auch in NCTC Klon 1469 und unter serumfreien Bedingungen für die durch S. typhimurium- Flagellin induzierte IL-8 Sekretion in der humanen Kolonkarzinomzelllinie Caco2 nachgewiesen werden. Damit war diese Hemmung weder zellspezifisch noch spezifisch für die TLR4-abhängige Stimulation. Basierend auf dieser Arbeit wurde ein Modell für die Entstehung einer chronischen Entzündung im Intestinaltrakt entwickelt, welches Erklärungsansätze für die Entwicklung einer chronisch entzündlichen Darmerkrankung im Menschen liefern könnte.H. hepaticus is the prototype species of the enterohepatic group of Helicobacter species and leads to a persistent infection in mice. It is able to cause a chronic inflammation of the intestinal tract in immuno-deficient mice that resembles the common human inflammatory bowel diseases Crohn’s disease und ulcerative colitis. Therefore H. hepaticus is widely used as a model organism to study the possible immunological causes underlying the development of inflammatory bowel disease in the animal model. H. hepaticus can also lead to diseases in the liver and biliary tract of susceptible mouse strains (e.g. Balb/c, C3H/An) such as hepatitis and even liver cancer. But in most studies H. hepaticus was mainly used to trigger these diseases, while only little attention was paid to the bacterial determinants of pathogenesis. In this work the complete genome sequence of the H. hepaticus reference strain ATCC 51449 was determined and annotated in cooperation with GeneData, MWG Biotech and the Massachusetts Institute of Technology (MIT). The genome has a size of 1,799,146 bp and codes for 1,875 proteins. Generally the average similarity of the genome is about equal to the sequenced genomes of H. pylori and C. jejuni. But H. hepaticus misses most of the virulence factors of H. pylori such as adhesins (e.g. SabA, BabA, or AlpA), the vacuolating cytotoxin VacA and most genes of the cag pathogenicity island. On the other hand it possesses many orthologs of C. jejuni virulence factors like the cytolethal distending toxin CDT or the adhesion factor Peb1. In addition to several smaller genomic islands, the genome of H. hepaticus contains a large 71 kb genomic island, which we called HHGI1. It presumably codes for a type IV secretion system and several additional virulence factors. By a microarray-based genome comparison study, we could show that this island was missing in seven out of 13 isolates. While only mice that harbored an island positive strain showed signs of liver disease, not a single mouse with an island negative strain showed any pathological changes of the liver or the biliary tract. In cooperation with the MIT, it was shown in an animal model that two island negative strains led to a reduced colonization and weaker inflammation of the liver compared to the island positive reference strain ATCC 51449. By the genome comparisons, it was also shown that despite low sequence variability the genome contents of different H. hepaticus isolates can differ widely and that smaller islands are either present or absent in different strains. In the framework of these investigations, several isogenic H. hepaticus mutants in the HHGI1 island were constructed. These mutants showed in comparison to the wild type a deficiency to activate macrophages, but the exact mechanism could not be identified so far. The isogenic mutants are currently further tested in animal models for their disease-eliciting potential. Because no well-characterized cell culture model was yet available for the in vitro examination of H. hepaticus-associated pathogenesis, such models were established in this dissertation. Therefore the murine intestinal epithelial cell line m-ICcl2 which resembles the primary habitat of H. hepaticus in the mouse caecum, the murine hepatocyte cell line NCTC clone 1469 which imitates one possible secondary habitat (mouse liver canaliculi) and the murine macrophage cell line J774 were used. While a wide range of ligands for pattern recognition receptors were able to stimulate NCTC clone 1469 and J774, m-ICcl2 cells only reacted substantially to the TLR4 ligand E. coli LPS. Accordingly, infection with H. hepaticus led to a strong proinflammatory response in J774 und NCTC clone 1469, while m-ICcl2 cells were only weakly stimulated by H. hepaticus despite good adherence. It was shown that H. hepaticus LPS and flagellins are only weak stimulators of the innate immune system while, as the results suggested, the proinflammatory response was mainly induced by lipoproteins and probably also by peptidoglycans of H. hepaticus. By analyzing the global gene regulation in J774 and NCTC clone 1469 after coincubation with H. hepaticus, it was established that the proinflammatory response is not mainly dependent on NF-κB but on MAP kinases. Also, the global response of the cells resembled more those induced by intracellular than extracellular pathogens. In these model systems, HHGI1-negative strains or mutants in the HHGI1 island led to a weaker proinflammatory response than HHGI1-containing strains. This was also in concordance with a different regulation pattern of different factors like TLR2, IL- 12, NOD2 or Tollip. In m-ICcl2 cells, after coincubation with live H. hepaticus or lysates, a reduced secretion of MIP-2 after stimulation with E. coli LPS was observed. It was shown that H. hepaticus LPS is one important factor for this inhibition of LPS-induced MIP-2 secretion, but not the HHGI-1 island nor other presumed H. hepaticus virulence factors. On the mRNA level, the induction of other cytokines like TNF-α or MIP-1α was also reduced by H. hepaticus. We could show, that, as described in other cells before, a primary coincubation with E. coli LPS leads to a tolerance against a second stimulation round. This tolerance development was inhibited by H. hepaticus. Inhibition of the proinflammatory response by H. hepaticus LPS was also obtained with NCTC clone 1469 cells. When using the human intestinal epithelial carcinoma cell line Caco2, S. typhimurium flagellin triggered IL-8 secretion was almost completely reduced under serum-free conditions, while no inhibition was found under serum-containing conditions. Therefore, this inhibitory effect was neither cell-specific nor specific for induction via TLR4. Based on this work, a model for the development of a chronic inflammation of the intestinal tract could be established, which may offer possible explanations for the development of inflammatory bowel diseases in humans
PISM glacial cycle sensitivity experiments of the Antarctic Ice Sheet
No full textThis dataset contains PISM simulation results (http://www.pism-docs.org) of the Antarctic Ice Sheet based on code release v1.0-paleo-ensemble (https://doi.org/10.5281/zenodo.3574033). PISM is the open-source Parallel Ice Sheet Model developed mainly at UAF, USA and PIK, Germany.
With the help of added python scripts, all figures can be reproduced as in the journal publication:
- Albrecht et al., 2020, doi:10.5194/tc-14-599-2020.
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Data:
Find PISM results as netCDF data. See 'README.md' for a list of all performed experiment.
All forcing input data for the experiments and plots can be downloaded and remapped via https://github.com/pism/pism-ais. Some of the original input data files are freely available, for others please contact the author or the corresponding data publisher.
Figure plotting scripts (jupyter notebook based on python, see https://jupyter.org) in 'plot_scripts' access the uploaded PISM results in 'model_data' and save the plots to 'final_figures'. Jupyter notebook can be run in the browser and shared, see https://nbviewer.jupyter.org/url/www.pik-potsdam.de/~albrecht/notebooks/paleo_paper/paleo_paper_final.ipynb.
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Contact:
Albrecht, Torsten ([email protected]) ; Potsdam-Institute for Climate Impact Research (PIK), Potsdam, German
Die Erfolgsfaktoren für unternehmerisches E-Mail-Marketing nach Dr. Torsten Schwarz am Praxisbeispiel ERGOTOPIA GmbH
No full textThis scientific document reveals the results of an empirical examination within the realm of entrepreneurial e-mail-marketing which is based on a literature review by technical author Dr. Torsten Schwarz. Using the start-up company ERGOTOPIA as a practical example, the author of the master thesis investigates whether the explanations of Dr. Schwarz match with the practical implementation of ERGOTOPIA.
Precisely, the scientific paper focuses on the examination of the four aspects lead generation, newsletter-design, software-requirements and performance measurement through monitoring with regard to successful realization of e-mail-marketing campaigns. The empirical part of this examination is made of the introduction as well as the analysis of two conducted so called split-tests that compare specific aspects of the newsletter-design and measure data-driven results to show which kind of aspect produced the more successful campaign.
This way the author proves whether the recommendations by Dr. Schwarz are practically relevant for the company ERGOTOPIA
Invitation to Dialogue - A Progress Report
No full textFragmentation of knowledge and life milieux, so often associated with specialization in science and planning, provided the broad challenge in science and planning, provided the broad challenge for a DIALOGUE PROJECT initiated by Torsten Hägerstrand and Anne Buttimer in Sweden during the Academic Years 1977-1979. The initial incentive for confronting such a wide-ranging set of issues arose from a paper on Values in Geography (Buttimer, 1974), after which the author was invited as a Fulbright lecturer to offer a series of seminars in Lund on problems of knowledge and experience. More than forty participants from ten widely different disciplines took part in this seminar, and foundations were laid for an experientially-grounded approach to the problems of communication across disciplines. The present project was initiated when Anne Buttimer was invited to accept a full time position in Sweden by the Humanistisk-Samhällsvetenskapliga Forskningsrådet (Council for Humanities and Social Science) in 1977. Financial support for this pilot phase of the Dialogue Project was granted by the Swedish Committee for Future Oriented Research and the Bank of Sweden Tercentenary Foundation. The geography department at the University of Lund continues to provide material and administrative help, with Torsten Hägerstrand as Co-Director
Invitation to Dialogue - A Progress Report
No full textFragmentation of knowledge and life milieux, so often associated with specialization in science and planning, provided the broad challenge in science and planning, provided the broad challenge for a DIALOGUE PROJECT initiated by Torsten Hägerstrand and Anne Buttimer in Sweden during the Academic Years 1977-1979. The initial incentive for confronting such a wide-ranging set of issues arose from a paper on Values in Geography (Buttimer, 1974), after which the author was invited as a Fulbright lecturer to offer a series of seminars in Lund on problems of knowledge and experience. More than forty participants from ten widely different disciplines took part in this seminar, and foundations were laid for an experientially-grounded approach to the problems of communication across disciplines. The present project was initiated when Anne Buttimer was invited to accept a full time position in Sweden by the Humanistisk-Samhällsvetenskapliga Forskningsrådet (Council for Humanities and Social Science) in 1977. Financial support for this pilot phase of the Dialogue Project was granted by the Swedish Committee for Future Oriented Research and the Bank of Sweden Tercentenary Foundation. The geography department at the University of Lund continues to provide material and administrative help, with Torsten Hägerstrand as Co-Director
Living labs as a concept and place for holistic sustainability education
No full textThis chapter has its origins in the authors’ activities in the field of teaching and research of solar energy in buildings at the Vallès School of Architecture (ETSAV) of Universitat Politècnica de Catalunya (UPC), which started as early as in 2003. In 2008 the author initiated and directed the first Solar Decathlon project of UPC, leading a team of 100 students and 50 companies in a 2-year process of the design, construction and operation of the energy self-sufficient solar house LOW3. This unique and transformational teaching and learning experience (for all student participants, but also for the author) led to the author’s conviction that experience-based, collaborative and transdisciplinary project-based learning in non-formal learning environments is highly effective and deeply necessary in the education of future architects, offering immense possibilities for a disciplinary as well as holistic approach to sustainability education.Objectius de Desenvolupament Sostenible::4 - Educació de QualitatObjectius de Desenvolupament Sostenible::7 - Energia Assequible i No ContaminantObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats SosteniblesObjectius de Desenvolupament Sostenible::13 - Acció per al ClimaObjectius de Desenvolupament Sostenible::12 - Producció i Consum ResponsablesPostprint (published version
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