Lokales Erregerspektrum der sekundären Peritonitis und Besonderheiten der Pharmakokinetik von Ceftriaxon und Linezolid bei kritisch kranken Patienten

The common goal of these studies was optimizing antibiotic therapy for critically ill patients with secondary peritonitis. We focused on the pharmacokinetics of two common antibiotics, ceftriaxone and linezolid. The first study investigated the unbound concentrations of ceftriaxone in 20 ICU patients, treated with 2g daily, by a new ultrafiltration method and high-performance liquid chromatography (HPLC). All but one patient showed concentrations in published therapeutic ranges. Compared to healthy volunteers, the unbound fraction was higher in ICU patients. The highest fractions were found in patients with renal impairment and/or severe hyperbilirubinemia. The clearance was linearly correlated with the estimated glomerular filtration rate. After all, protein binding of ceftriaxone does not seem to have high influence on the question whether standard dosing of ceftriaxone for ICU patients is appropriate or not. In the second study, plasma concentrations of linezolid were determined in 20 ICU patients treated with 600 mg twice daily. As measures of exposure to linezolid, area under the concentration-time curve (AUC) and trough concentrations (Cmin) were calculated and compared to published therapeutic ranges (AUC 200-400mg*h/L, Cmin 2-10mg/dl). Coadministration of inhibitors and inducers of cytochrome P450 and/or P-glycoprotein, which are suspected to influence pharmacokinetics of linezolid, was noted. Drug exposure was highly variable. Only a minority of patients had values within the target ranges. Coadministration of inhibitors was associated with a trend to higher drug-exposure. Patients treated with levothyroxine, an inductor of P-glycoprotein, showed exceedingly low drug exposure (AUC ~60 mg*h/L, Cmin < 0.4mg/L). In the third study antibiotic regimens for treatment of secondary peritonitis were investigated for their presumed activity. We defined the “spectrum adequacy rate” (SAR) as the probability that all relevant pathogens in one patient are covered by the used antibiotic regimen. Data from 242 patients (88 community acquired, 154 postoperative cases) were obtained retrospectively. Enterococci were isolated in 47.1% of all patients, followed by Eschericia coli (42.6%), other enterobacteriaceae (33.1%) and anaerobes (29.8%). The susceptibility rates and SAR were lower in postoperative cases. The following regimens yielded a SAR>95 % when Enterobacteriaceae only were considered: piperacillin/tazobactam+gentamicin, cefotaxim (equivalent to ceftriaxone, only for community acquired cases), cefotaxim+gentamicin, meropenem+gentamicin or tigecyclin+ciprofloxacin. When also enterococci were considered, all betalactam based regimens required combination with vancomycin or linezolid for a SAR>95%. These three studies showed, that there are population-specific particularities for both, pharmacokinetics and susceptibility of pathogens. This knowledge might be helpful in choosing an optimized antibiotic therapy.Das gemeinsame Ziel der vorliegenden Arbeiten war eine Optimierung antibiotischer Therapien kritisch kranker Patienten mit sekundärer Peritonitis. Der Fokus lag auf der Pharmakokinetik zweier gängiger Antibiotika, Ceftriaxon und Linezolid. Zum einen wurde bei 20 Intensivpatienten, unter Ceftriaxontherapie (2g täglich intravenös), die ungebundene Fraktion des Antibiotikums mittels Ultrafiltration und high-performance liquid chromatography (HPLC) bestimmt. Bei 19 Patienten zeigten sich Konzentrationen im publizierten sicher therapeutischen Bereich. Verglichen mit Proben gesunder Freiwilliger wurden generell höhere ungebundene Fraktionen gefunden. Die höchsten zeigten Patienten mit schwerer Niereninsuffizienz und/oder Hyperbilirubinämie. Die Clearance korrelierte gut mit der glomerulären Filtrationsrate. Die Proteinbindung von Ceftriaxon scheint somit eine untergeordnete Rolle für die Frage zu spielen, ob Standarddosen bei Intensivpatienten angemessen sind oder nicht. Zum anderen wurde bei 20 Intensivpatienten unter Linezolidtherapie (2x600 mg täglich intravenös) die totalen und ungebundenen Medikamentenspiegel bestimmt. Als Maß für die Linezolidexposition wurden die area under the concentration-time curve (AUC) und die Tal-Konzentrationen (Cmin) berechnet und mit publizierten therapeutischen Bereichen (AUC 200-400mg*h/L, Cmin 2-10mg/dl) verglichen. Komedikationen mit Inhibitoren bzw. Induktoren des CYP450 und/oder P-Glycoprotein (P-gp) wurden berücksichtigt, da diese in Verdacht stehen die Pharmakokinetik (PK) von Linezolid zu beeinflussen. Es zeigte sich eine deutliche Streuung bei den Medikamentenspiegeln, nur 6 Patienten zeigten Werte im therapeutischen Zielbereich. Eine Komedikation mit Inhibitoren des CYP450 und/oder P-gp ging tendenziell mit höheren freien Medikamentenspiegeln einher, wohingegen Patienten unter Levothyroxin, einem Induktor des P-gp, auffällig niedrige Werte boten (AUC ~60 mg*h/L, Cmin < 0.4mg/L). In der dritten Arbeit wurde die prinzipielle Wirksamkeit antibiotischer Regime bei der Therapie von sekundären Peritonitiden untersucht. Als „spectrum adequacy rate“ (SAR) wurde die Wahrscheinlichkeit, alle bei einem Patienten nachgewiesenen relevanten Erreger durch ein angewandtes Antibiotikaregime abzudecken, definiert. Retrospektiv wurden die Daten von 242 Patienten (88 mit ambulant erworbener und 154 mit postoperativer Peritonitis) ausgewertet. In 47.1% der Fälle wurden Enterokokken isoliert, gefolgt von Escherichia coli (42.6%), anderen Enterobacteriaceae (33.1%), Anaerobiern (29.8%). Bei postoperativen Peritonitiden war sowohl die Sensibilität allgemein als auch die SAR geringer. Wurden nur Enterobacteriaceae berücksichtigt, lieferten folgende Therapieregime eine SAR >95%: Piperacillin/Tazobactam+Gentamicin, Cefotaxim (äquivalent zu Ceftriaxon; nur bei ambulant erworbenen Fällen), Cefotaxim+Gentamicin, Meropenem+Gentamicin oder Tigecyclin+Ciprofloxacin. Wurden zudem noch Enterokokken berücksichtigt, war für Therapieregime die auf Betalaktamantibiotika basierten eine Kombination mit Vancomycin oder Linezolid nötig um eine SAR >95% zu erzielen. Es konnte gezeigt werden, dass sowohl bei der Pharmakokinetik als auch bei Häufigkeit und Sensibilität relevanter Pathogene populationsspezifische Unterschiede bestehen, deren Kenntnis für eine optimierte Antibiotikatherapie hilfreich sein kann

Television And Internet As Converging Knowledge Instances For Children

Wissenssendungen, die speziell für Kinder gemacht sind, wie «Die Sendung mit der Maus», «Löwenzahn», «Wissen macht Ah!», «Willi will's wissen», und Kindernachrichten wie «Logo» und «Neuneinhalb» finden ihr Publikum. Ältere Kinder schauen bereits lieber Wissenssendungen für Erwachsene wie Galileo und Wunderwelt Wissen. Die Nutzung dieser Sendungen zeigt, dass Kinder ihren Wissensdurst auch mit und beim Fernsehen stillen. Aber was wollen Kinder vom Fernsehen wissen? Welche Wissensbereiche spielen eine Rolle? Wie verbinden die Kinder dabei die Nutzung des Fernsehens und des Internets? Anhand der Ergebnisse verschiedener empirischer Studien der Autoren aus den letzten Jahren stellt der Beitrag die konvergenten Aspekte von Fernsehen und Internet als Wissensinstanzen für Kinder dar. Dabei wird sowohl auf die Rolle der beiden Medien bei der Informationsbeschaffung und Wissensvermittlung für unterschiedliche Altersgruppen und verschiedene Bildungshintergründe eingegangen wie auf geschlechtsspezifische Unterschiede. Der Beitrag mündet in Konsequenzen für konvergente Angebote zu Bildung und Wissen in Fernsehen und Internet.Knowledge programmes made especially for children, such as "Die Sendung mit der Maus", "Löwenzahn", "Wissen macht Ah!", "Willi will's wissen", and children's news programmes such as "Logo" and "Neuneinhalb" find their audience. Older children already prefer to watch knowledge programmes for adults such as Galileo and Wunderwelt Wissen. The use of these programmes shows that children also quench their thirst for knowledge with and while watching television. But what do children want to know from television? Which areas of knowledge play a role? How do children combine their use of television and the Internet? Based on the results of various empirical studies conducted by the authors in recent years, the article presents the convergent aspects of television and the Internet as instances of knowledge for children. The role of both media in the acquisition of information and the transfer of knowledge for different age groups and different educational backgrounds as well as gender-specific differences are discussed. The article leads to consequences for convergent offers of education and knowledge on television and the internet

Del «edificio escolar» a la «arquitectura escolar» - Técnicos escolares, grandes edificios escolares y arquitectura educativa en Prusia y los Estados Unidos en el siglo XIX

The history of school buildings is commonly written as a history of architecture, focusing on outstanding architects and buildings. However, the connection between pedagogical-administrative prescriptions and educational architecture has been studied less, particularly in the nineteenth century. This article highlights the often-overlooked agency of school technicians and proposes to interpret the nineteenth-century history of building schools as a history of implementing pedagogical-administrative objectives. The design of schools followed the inner differentiation of school curricula, at the same time being affected by the growth of school sizes prompted by school management structures and their efficiency aims. We will show how in larger cities the initial one-classroom schools developed into multiple-classroom buildings, taking on their final form in “grand school buildings”. The organizational developments tried and tested here would later become the national standard, with rural schools following with a certain delay. In order to grasp the emergence of the phenomena of these “grand school buildings” we combine the Prussian and US-American cases in their transatlantic connection  in order to comprehend the transnational dimension of school building norms. Being closely connected through mutual observation, the US and Prussian contexts established two decisive aspects: in the Prussian case, the division into separate classrooms as functional units of school construction was implemented, while in the United States additional school rooms such as the assembly hall and specific subject-related rooms were introduced. “Grand school buildings” initiated the interest of the architectural profession, leading to negotiations between school technicians and architects.La historia de los edificios escolares se presenta comúnmente como una historia de la arquitectura, centrándose en arquitectos y edificios excepcionales. La conexión entre las prescripciones pedagógico-administrativas y la arquitectura educativa ha sido menos investigada, particularmente para el siglo XIX. En este artículo se acentúa el impacto de los técnicos escolares, a menudo pasada por alto, y se propone interpretar la historia de la construcción de escuelas del siglo XIX como una historia de la aplicación de objetivos pedagógico-administrativos. El diseño de las escuelas siguió la diferenciación interna de los programas escolares. Al mismo tiempo, el diseño se vio afectado por el crecimiento de los edificios escolares impulsado por las estructuras de administración escolar y sus objetivos de eficiencia. En este artículo, se analiza cómo en las grandes ciudades las escuelas unitarias se convirtieron en edificios con múltiples aulas, tomando su forma final de grandes edificios escolares. Los desarrollos en la organización probados en las urbes se convirtieron más tarde en el estándar nacional, con las escuelas rurales siguiéndolas con cierto retraso. Para captar la aparición del fenómeno de estos grandes edificios escolares combinamos los casos prusiano y estadounidense en su conexión transatlántica para comprender la dimensión transnacional de la aparición de normas para los edificios escolares. Conectados por observaciones mutuas, los contextos estadounidense y prusiano establecieron dos aspectos decisivos y diferentes: en el caso prusiano, se aplicó la división de aulas separadas como unidades funcionales de la construcción de escuelas, mientras que en el caso estadounidense se introdujeron aulas adicionales como el auditorio y salas específicas para asignaturas específicas. Los grandes edificios escolares despertaron el interés de los arquitectos, lo que dio lugar a negociaciones entre los técnicos escolares y los arquitecto

Affekttheorien für die Medienforschung nutzbar machen

Zentrales Anliegen des Beitrags ist es, Affekttheorien für die empirische Anwendung in der Kommunikations- und Medienwissenschaft nutzbar zu machen. Dazu stellen wir zunächst zentra-le Stränge der Emotionsforschung in der Rezeptions- und Wirkungsforschung sowie der Medi-entextanalyse dar, klären die von ihnen verwendeten Begriffe und machen ihre Bezüge zur Af-fektforschung deutlich. Daran anschließend führen wir knapp in aktuelle affekttheoretische An-sätze ein, beginnend mit einer Rekonstruktion früher Auseinandersetzungen in den Cultural Stu-dies, und entwickeln schließlich ein Analysemodell, mit dem Affekte als sozial-relationale Phä-nomene der Medienkommunikation empirisch analysiert werden können. Zur Exemplifizierung beziehen wir uns primär auf das Medium Fernsehen als einem Modus audiovisueller Kommuni-kation. Diese Betrachtung erlaubt jedoch auch weiterführende Überlegungen zur Bedeutung affektiver Dynamiken zwischen Medientechnologien, -texten und ihren Nutzer_innen.This article focuses on affect theories and their relevance for communication and media studies. Relying on the strength and potential of the different ‚affective turns’, we develop an empirical approach to analyze affect as a relational phenomenon within media communication. To begin with, we introduce key concepts of emotion in audience and reception studies and in textual media analyses. Thereby, we try to clarify their central understanding of emotion and affect and explain their reference to contemporary affect theory. Introducing central strands of current affect theory, we develop an analytical approach to be used for empirical studies of affect in communication and media studies. Our considerations will be exemplified by the case of television. Nevertheless, the analytical approach provides the possibility for further reflections on the significance of affective dynamics within audiovisual media. We argue for an understanding of the affective dynamics of current media saturated societies

Knowledge in the making: methodological considerations on the production, dissemination, and usage of "small forms in education"

Collecting and producing mass data has offered an appealing way to condense educational phenomena. However, thus far, little attention has been given to the seemingly insignificant preprinted forms that represent the basis for compiling and aggregating data. Taking inspiration from science and technology studies and the ensuing development of so-called paper technologies, this article highlights the potential of small forms in education that were used to record, evaluate, and aggregate data for educational statistics. By suggesting a multi-level methodological approach that we frame as 3D hermeneutics, we seek to contribute a methodological proposal on how to analyse these materials and showcase what lies beneath – or what comes before – the knowledge produced by educational statistics. These analyses draw on pre-printed forms collected by the Prussian educational administration at the turn of the nineteenth century, and re-trace the contexts they were embedded in, examine their materiality, and reconstruct their usage

Digital SexEd im historischen Blick. Perspektivierung, Analyse und Tradierung als Beiträge der Historischen Bildungsforschung zum Digital Turn. Das Beispiel Instagram

Der Beitrag zeigt, wie Digitalität selbst zum Thema der Bildungsgeschichte werden kann. Der Autor beschreibt, inwiefern auch bekannte bildungshistorische Perspektiven sowie die Methoden der Foto- und Bildanalyse dazu dienen, die visuelle Kommunikation und Interaktion in digitalen sozialen Medien besser verstehen zu können. Dies stellt er anhand einer Reihe von Instagram-Kanälen aus dem Themenfeld der Sex Education dar. (DIPF/Orig.

Spectroscopic ellipsometry on tailored siloxane-based nanostructures for low-voltage dielectric elastomer actuators

To convert electric energy into mechanical motion dielectric elastomer actuators (DEAs) are known for their high strains combined with low power consumption. Based on micrometer-thick elastomer films DEAs are an established technology to serve as artificial muscles for soft robotics. The ‘Smartsphincter‘ project aims to develop artificial muscles to treat fecal incontinence. However, to use DEAs as medical implants, operation voltages have to be reduced from the kV-range well below the medically approved limit of 42 V. Hence, this work pursues the fabrication of nanometer-thin elastomer layers to enables the low-voltage operation of DEAs. To guarantee the acceptance as medical implant DEAs are composed of biocompatible materials. The excellent elasticity of cross-linked polydimethylsiloxane (PDMS) in combination with its biocompatibility renders PDMS the polymer of choice for a large range of medical applications, including DEAs. Due to its inherent chemical inertness combined with outstanding conductance, Au is considered as biocompatible electrode. Organic molecular beam deposition (OMBD) is a versatile technique employed to produce nanometer-thin films with unique homogeneity, however, for polymer material OMBD faces the challenge of evaporating oligomers at a reasonable rate at temperatures well below thermal degradation. Herein, we present thermally evaporated linear PDMS serving as thin polymer films with a tailored molecular weight distribution (cp. Section 2.1). Limited by intermolecular interactions between the methyl side groups, molecular weights of up (6.000±100) g/mol corresponding to up to 80 repeating units of dimethylsiloxane are evaporated before thermal degradation. The functional group density per repeating unit dimethylsiloxane is adjusted between (2.8±0.2) g/mol and (11±0.1) g/mol. These thermally evaporated PDMS fractions exhibits a narrowed MWD with polydispersity index (PDI) of 1.06±0.02 compared to the highly dispersive supplied polymer. The low PDI enables precise definition of functional group density anticipated to qualify for functionalized surfaces of biomedical devices e.g. microfluidic applications or tailoring cell-polymer interactions. Furthermore, we highlight the evaporation of high molecular weight PDMS chains to be of great importance to realize low elastic modulus cross-linked thin elastomer films. Cross-linking of these PDMS macromolecules is activated through ultraviolet (UV) radiation, which induces a photo-initiated reaction of radicalized functional vinyl terminations. Nano-indentation and infrared spectroscopic studies clarify the understanding of the cross-linking mechanism in section 2.2 and section 2.4. Due to the strong absorption coefficient of PDMS in the UV-range, the cross-linking density is increased within the first nanometers of the film compared to the bulk indicating a skin-like SiO2 surface. This stiffened silica-like surface combined with heat input through UV irradiation results in isotropic distributed wrinkled surface microstructures. Magnetron-sputtered gold coatings can release these wrinkled microstructures, which is accounted for a pre-stretching of the Au/SiO2/PDMS heterostructure. This suggests these heterostructures to qualify for stretchable electronics. One straightforward approach for increased electrode flexibility is a reduced metalfilm thickness, which is applicable for gold films above 10nm revealing the drawback of reduced conductivity (cp. section 2.2). Regarding DEA-based artificial muscles, strains higher than 10% with maintained conductivity are needed to provide millisecond response time. As an important milestone within the ‘SmartSphincter‘-project an OMBD system was setup, combing the deposition of metal and polymer as well as the UV-polymerization. Simultaneous in situ spectroscopic ellipsometry (SE) monitoring paves the way to tailor soft multilayer metal/elastomer heterostructures on the nanometer scale (cp. section 2.5). Synthesized bi-functional thiol-terminated PDMS was specifically tailored concerning the MWD for thermal evaporation to serve as self-assembled adhesion monolayer (SAM) for gold. It is hypothesized that the SH-PDMS chains and the subsequently evaporated Au form a viscous composite. Cross-linked to the underlying PDMS membrane, the SH-PDMS induces stability, which permits the generation of confluent Au films with a thickness as low as (12±1) nm. We demonstrated a remarkably reduced percolation threshold at a film thickness of (4.4±0.3)nm if a nanometer-thin wrinkled Cr-interlayer is applied to the PDMS membrane. Our results suggest a dramatic improvement towards homogeneous Au growth on soft PDMS membranes. We claim the specifically tailored hetero nanostructures to retrieve some flexibility under strain due to either localized covalent gold-thiol bonds or pre-stretched nanometer-thin Cr-wrinkles, especially beneficial for soft and strechable nanoelectrodes. To proove the envisioned concept a single layer DEA is presented (cp. section 2.4). Manufactured on a 25 μm-thick polyetheretherketone (PEEK) cantilever the bending characteristic gave evidence of a maintained actuation efficiency for a 200 nm-thin film, activated with voltages from 1 to 12 V, compared to a 4 μm-thick, spin-coated film, operated between 100 and 800 V. The force of this 200 nm-thin film cantilever actuator was about 10−4N. Thus, a multilayer DEA with more than 104 layers would reach forces comparable to natural muscles. To tackle the major drawback of OMBD, exhibiting evaporation rates limited below 0.1 nm/s, a cooperative study with the EMAP in Dübendorf aimed to validate alternate current electro-spray (ACES) as a cost-effective growth technique for nanometer-thin PDMS films. As presented for OMBD, in situ SE real-time analysis approved ACES to qualify for DEA manufacturing (Florian Weiss et al., see publication list) permitting deposition rates above 10 μm/h. However, at these growth rates we obtained rather free-standing islands than a confluent film formation resulting in micrometer-rough surface morphologies. Thus, the outstanding homogeneity with sub-nanometer surface roughness accentuates OMBD better for soft nanotechnology. Combining OMBD self-assembly with SE real-time tailoring of the electronic and optical properties allows the manufacturing of the nanometer-thin heterostructures with a unique precision. Soft, transparent, and biocompatible hetero-nanostructures based on electrically activated polymers are applicable to bio-MEMs, in nanophotonics as soft tuneable gratings or plasmonic absorbers, and flexible electronics. We propose a high impact for these nanostructures developing DEAs towards low-voltage operation. As unique property, sensing and actuating can be achieved concurrently within the same DEA hetero nanostructure. The fabrication of biocompatible actuator/sensor structures with compliance similar to that of human tissue is key to mimic natural muscles for biocompatible implants or soft robotics

Mediale Affektökonomie: Emotionen im Reality TV und deren Kommentierung bei Facebook

Emotions in reality TV: How facebook comments produce affective media practices and generate affiliations.Wie werden in Reality TV-Formaten ausgehandelte Regeln des emotionalen Ausdrucks und deren Inszenierung auf Facebook bewertet? Welche unterschiedlichen Orientierungen in Bezug auf andere Körper entstehen dabei? Wie werden dadurch Zugehörigkeitsgefühle erzeugt oder Ausschlüsse vorgenommen? Mit dem Konzept der medialen Affektökonomie beschreibt die Autorin, wie Emotionen in digitalen vernetzten Medienumgebungen geordnet werden. Dabei kann sie aufzeigen, dass insbesondere Ambivalenzen, Paradoxien und die Figur des Spielverderbers oder der Spielverderberin einen handlungssteigernden Charakter haben und affektive Medienpraktiken des Publikums evozieren