Kontrapunkt: Holzfassaden: Konstruktion + Gestaltung = Baukultur?

Die Schweiz ist von einer langen Holzbautradition geprägt. Die historischen Holzbauten haben im Laubsäglistil- Chalet und schliesslich im banalen Ferienhausbau Fortsetzung gefunden. Der alpine Holzfassadencharme stiftet Identität, erfüllt Sehnsüchte und ist damit auch ein relevanter Wirtschaftsfaktor. Ich denke, es besteht ein breiter Konsens: Dies ist Schweizer Baukultur. In den letzten drei Dekaden hat sich der Schweizer Holzbau konstruktiv und technisch völlig neu aufgestellt. Wie müssen diese neuen Holzbauten aussehen, damit sie als Holzbau erkannt werden, ebenso identitätsstiftend sind und eine neue (Holz-)Baukultur initiieren

Schweizer Holzbaukultur: Tradition, Moderne, Zukunft

Der Holzbau hat in der Schweiz eine lange, regional differenzierte Tradition. Der aus der voralpinen Architektur abgeleitete Schweizer Holzstil resp. das Chalet sorgten seit dem ausgehenden 19. Jahrhundert für ein Holzbau-Klischee, das den Tourismus bediente und bis heute die scheinbar beste Lösung für die Weiterentwicklung des ländlichen Raums darstellt. Dieser Prozess vollzog sich unter dem Radar der modernen, internationalen Architektur. Der sukzessive Einsatz von Eisen und Beton seit dem ausgehenden 19. Jahrhundert hatte auch in der Schweiz zu einer Akademisierung der Ingenieurwissenschaften geführt: 1856 wurde Gottfried Semper (1803–1879) an die ETH Zürich berufen und eine Bauschule gegründet, die sich mit Ingenieuren wie Emil Mörsch (1872–1950) zu einem Zentrum des Bauens mit Stahlbeton entwickelte. Zur Etablierung dieser neuen Materialien, die für den Bau der Infrastruktur und hier in erster Linie des Eisenbahnnetzes eine wesentliche Rolle spielten, wurde 1880 eine Materialprüfungsanstalt eingerichtet. Die Folge: Das Handwerk Holzbau geriet ins Hintertreffen. Die vorherrschende wie populäre Chaletarchitektur galt in Fachkreisen bald schon als überholt, obwohl auch Stararchitekten wie etwa Karl Friedrich Schinkel (1781–1841) «Schweizerhäuschen» errichtet hatten und vorfabrizierte Bauten im Schweizer Holzstil aus sezialisierten Fabriken international geordert wurden

Automated seamless DNA co-transformation cloning with direct expression vectors applying positive or negative insert selection

<p>Abstract</p> <p>Background</p> <p>Molecular DNA cloning is crucial to many experiments and with the trend to higher throughput of modern approaches automated techniques are urgently required. We have established an automated, fast and flexible low-cost expression cloning approach requiring only vector and insert amplification by PCR and co-transformation of the products.</p> <p>Results</p> <p>Our vectors apply positive selection for the insert or negative selection against empty vector molecules and drive strong expression of target proteins in <it>E.coli </it>cells. Variable tags are available both in N-terminal or C-terminal position. A newly developed β-lactamase (ΔW290) selection cassette contains a segment inside the β-lactamase open reading frame encoding a stretch of hydrophilic amino acids that result in a T7 promoter when back-translated. This position of the promoter permits positive selection and attenuated expression of fusion proteins with C-terminal tags. We have tested eight vectors by inserting six target sequences of variable length, provenience and function. The target proteins were cloned, expressed and detected using an automated Tecan Freedom Evo II liquid handling work station. Only two colonies had to be picked to score with 85% correct inserts while 80% of those were positive in expression tests.</p> <p>Conclusions</p> <p>Our results establish co-transformation and positive/negative selection cloning in conjunction with the provided vectors and selection cassettes as an automatable alternative to commercialized high-throughput cloning systems like Gateway^®or ligase-independent cloning (LIC) <b/>.</p

Epidemiology, genetic variants and clinical course of natural infections with Anaplasma phagocytophilum in a dairy cattle herd

Background: Anaplasma phagocytophilum is an obligate intracellular, tick-transmitted bacterium that causes granulocytic anaplasmosis in humans and several mammalian species including domestic ruminants where it is called tick-borne fever (TBF). Different genetic variants exist but their impact with regard to putative differences in host associations and pathogenicity are not yet completely understood. Methods: Natural infections with A. phagocytophilum in a dairy cattle herd in Germany were investigated over one pasture season by using serology, haematology, blood chemistry and polymerase chain reaction (PCR). Sequence analysis of partial 16S rRNA, groEL, msp2 and msp4 genes of A. phagocytophilum was carried out in order to trace possible genetic variants and their relations between cattle, roe deer (Capreolus capreolus) and ticks (Ixodes ricinus) in this area. Results: In total 533 samples from 58 cattle, 310 ticks, three roe deer and one wild boar were examined. Our results show (i) typical clinical symptoms of TBF in first-time infected heifers, such as high fever, reduced milk yield, lower limb oedema and typical haematological and biochemical findings such as severe leukopenia, erythropenia, neutropenia, lymphocytopenia, monocytopenia, a significant increase in creatinine and bilirubin and a significant decrease in serum albumin, gamma-GT, GLDH, magnesium and calcium;(ii) a high overall prevalence of A. phagocytophilum infections in this herd as 78.9% (15/19) of the naive heifers were real-time PCR-positive and 75.9% (44/58) of the entire herd seroconverted;and (iii) a high level of sequence variation in the analysed genes with five variants of the 16S rRNA gene, two variants of the groEL gene, three variants of the msp2 gene and four variants in the msp4 gene with certain combinations of these variants. Conclusions: In cattle particular combinations of the genetic variants of A. phagocytophilum occurred, whereas three roe deer showed different variants altogether. This is indicative for a sympatric circulation of variants in this small geographical region (< 1 km(2)). Both re-and superinfections with A. phagocytophilum were observed in five cattle showing that infection does not result in sterile immunity. For prevention of clinical cases we suggest pasturing of young, not pregnant heifers to reduce economical losses

Guidance for evaluating integrated surveillance of antimicrobial use and resistance

Antimicrobial resistance (AMR) resulting from antimicrobial use (AMU) is an emerging threat to global health. One of the key elements for a better understanding and management of AMU and AMR is to develop effective and efficient integrated surveillance systems that consider the complex epidemiology of these issues and the impacts of resistance on humans, animals and the environment. Consequently, for this project, an international consortium of experts from multiple fields called CoEvalAMR was formed with the objectives to study user needs, characterise and compare existing tools for the evaluation of integrated AMU and AMR surveillance, apply them to case studies, and elaborate guidance on the purpose-fit selection and the use of the tools. For the comparison of evaluation tools, questions were extracted from existing tools and attributed to themes, to assess the user needs, interviews were conducted with national key stakeholders, and we applied a series of different evaluation tools to understand and document their strengths and weaknesses. The guidance was refined iteratively. From 12 evaluation tools, 1117 questions/indicators were extracted and attributed to seven emerging themes. Twenty-three experts were interviewed, who suggested to increase the ease-of-use, grant open access, provide web-based interfaces and allow results to be automatically generated. Respondents also wished for tools providing the flexibility to conduct a rapid review, or an in-depth analysis of the surveillance system, depending on the evaluation objectives. The case studies emphasised that proper evaluations require adequate resources, typically requiring the involvement of several assessors and/or stakeholders, and can take weeks or months to complete. The resulting web-based guidance comprises six main sections: 1. Introduction to surveillance evaluation, 2. Evaluation of surveillance for AMU and AMR, 3. Evaluation tools, 4. Support for selecting an evaluation tool, 5. Case studies and 6. Directory of existing tools. The audience for the guidance is personnel working in public, private, and non-governmental organisations, from public health, animal health, plant health and environmental health, at local, national and international levels. We conclude that the field is challenged by opposing user needs for reduction and simplicity versus system approaches allowing the synthesis of that knowledge to sufficiently reflect the complexity of AMU and AMR ecology for real-world decisions. The CoEvalAMR web platform allows a better understanding of the different evaluation tools and assists users in the selection of an approach that corresponds to their evaluation needs. The CoEvalAMR consortium continues to address remaining gaps and consolidate evaluation tools and approaches in the future