272 research outputs found
HUNZIKER (Dr Otto [DPI], Otto [NDP])
No full textDubois Patrick. HUNZIKER (Dr Otto [DPI], Otto [NDP]). In: Le dictionnaire de pédagogie et d'instruction primaire de Ferdinand Buisson : répertoire biographique des auteurs. Paris : Institut national de recherche pédagogique, 2002. p. 87. (Bibliothèque de l'Histoire de l'Education, 17
Can we use seismic reflection data to infer the interconnectivity of fracture networks?
No full textThis is a pre-copyedited, author-produced PDF of an article published in Geophysical Journal International following peer review. The version of record “Rubino, J. G., Barbosa, N. D., Hunziker, J., & Holliger, K. (2022). Can we use seismic reflection data to infer the interconnectivity of fracture networks?. Geophysical Journal International, 231(2), 996-1010” can be found at: https://doi.org/10.1093/gji/ggac23
Leadership in medical emergencies depends on gender and personality
No full textLeadership is an important predictor of team performance in medical emergencies. There are no data on why some healthcare workers take the lead in emergencies while others do not. Accordingly, the aim of the study was to determine predictors of leadership in a medical emergency
ABC versus CAB for cardiopulmonary resuscitation: a prospective, randomized simulator-based trial
No full textQUESTIONS UNDER STUDY: After years of advocating
ABC (Airway-Breathing-Circulation), current guidelines
of cardiopulmonary resuscitation (CPR) recommend CAB
(Circulation-Airway-Breathing). This trial compared ABC
with CAB as initial approach to CPR from the arrival of
rescuers until the completion of the first resuscitation cycle.
METHODS: 108 teams, consisting of two physicians each,
were randomized to receive a graphical display of either the
ABC algorithm or the CAB algorithm. Subsequently teams
had to treat a simulated cardiac arrest. Data analysis was
performed using video recordings obtained during simulations.
The primary endpoint was the time to completion
of the first resuscitation cycle of 30 compressions and two
ventilations.
RESULTS: The time to execution of the first resuscitation
measure was 32 ± 12 seconds in ABC teams and 25 ±
10 seconds in CAB teams (P = 0.002). 18/53 ABC teams
(34%) and none of the 55 CAB teams (P = 0.006) applied
more than the recommended two initial rescue breaths
which caused a longer duration of the first cycle of 30
compressions and two ventilations in ABC teams (31 ± 13
vs.23 ± 6 sec; P = 0.001). Overall, the time to completion
of the first resuscitation cycle was longer in ABC teams (63
± 17 vs. 48 ± 10 sec; P <0.0001).CONCLUSIONS: This randomized controlled trial found
CAB superior to ABC with an earlier start of CPR and a
shorter time to completion of the first 30:2 resuscitation
cycle. These findings endorse the change from ABC to
CAB in international resuscitation guidelines
Targeted delivery of advanced functionality by nanomaterials : focus on nucleic acids delivery by novel block copolymers
No full textAbstract: Smart drug delivery systems are versatile examples of successful nanomedicine with
potential in diagnostics and medical therapy. The thesis presents selected
approaches in current drug delivery systems in the (pre-)clinical trials, and deals with
potential side effects, including complement activation and hypersensitivity reactions
as well as the design requirements of the delivery systems. Furthermore, it presents
approaches of cationic block copolymers, which are capable to condense negatively
charged nucleic acid molecules such as plasmid deoxyribonucleic acid (pDNA) and
small interfering ribonucleic acid (siRNA) with the aim of efficient cell gene delivery
and specific gene suppression, respectively.
The first part addresses the transfection efficiency of circular versus linearized
plasmid DNA using a green fluorescent protein expressing vector with Lipofectamine
2000 and linear 25 kDA polyethylenimine (PEI). These results show a considerably
improved transfection efficiency with the circular compared to the linearized DNA for
the two transfection reagents. The electron microscopy images with Lipofectamine or
PEI demonstrate that the circular DNA gives rise to random coil appearance of
compact, spherical shape, while linearized DNA appear as worm-like strands.
Particle size and shape are important in the cell biology of endocytosis and
phagocytosis. The findings indicate that the shape of the transfection particle is vital
for successful gene transfer.
To develop a delivery system for gene therapy, two cationic diblock copolymers
consisting of primary and tertiary amines were synthesized and analyzed with
respect to DNA condensation properties, morphology of the condensed plasmid DNA
and transfection efficiency using two cell lines. This study revealed proof-of-concept
showing an order of magnitude lower transfection efficiency of primary amine diblock
copolymers compared to PEI after 48 h with increasing plasmid DNA concentration.
Furthermore, primary amines compared to tertiary ones show much stronger binding
to DNA and improved transfection efficiency. Transmission electron and atomic force
microscopy data revealed morphologies of primary and tertiary amines regarding the
condensation of the plasmid DNA, in agreement with the transfection efficiency.
In a second part the design and characterization of pentablock-based polyplexes
based on the combination of cationic pentablock copolymers with folic acid
functionalized copolymers for targeted specific siRNA delivery is described. The
achieved 31 % knockdown efficiency shows its potential regarding cancer gene
therapy. The pentablock architecture allows the formation of highly stable
micelleplexes of (21 ± 3) nm in 10 mM PBS buffer solution with a neutral surface
charge, excellent siRNA condensation properties, outstanding colloidal stability in
10 % serum over 24 h and biocompatibility deduced from the absence of
considerable cytotoxicity even after 48 h incubation. Furthermore, selective delivery
of the siRNA could be proven by the introduction of a ligand-linked block copolymer,
resulting in 31 % compared to 8 % gene suppression for targeted a non-targeted
micelleplexes. This pentablock-based delivery system might yield impact to future
delivery systems as well as being a potential platform to be applied in vivo for cancer
gene therapy. ---------- Zusammenfassung
Innerhalb des Bereichs der Nanomedizin weisen intelligente Wirkstoffabgabesysteme
ein großes Potenzial auf, sowohl hinsichtlich der Diagnostik wie auch der
medizinischen Therapie. Die vorliegende Arbeit stellt im Rahmen einer
Literaturrecherche ausgewählte Wirkstoffabgabesysteme vor, welche sich in (vor-)
klinischen Studien befinden, den Nebenwirkungen welche durch diese entstehen
können, im speziellen der Komplementaktivierung und Überempfindlichkeitsreaktionen,
sowie deren Konstruktionsanforderungen. Des weiteren werden in einem
experimentellen Teil kationische Block-Kopolymere präsentiert, welche in der Lage
sind, negativ geladene Nukleinsäuremoleküle zu binden - wie etwa Plasmid
Desoxyribonukleinsäure (pDNA) und kleine interferierende Ribonukleinsäuren
(siRNA) - mit dem Ziel der Transfektion von fremder DNA in die Wirtszellen und
damit der spezifischen Unterdrückung der Genexpression.
Der erste Teil der experimentellen Arbeit untersucht die Transfektionseffizienz von
zirkulärer gegenüber linearisierter Plasmid-DNA mittels eines Vektors, welcher ein
grün fluoreszierendes Protein exprimiert. Transfiziert wurde einerseits mit
Lipofectamine 2000 und andererseits mit linearem 25 kDa Polyethylenimin (PEI),
zwei etablierten Transfektionsreagenzien. Die Ergebnisse zeigen eine wesentlich
verbesserte Transfektionseffizienz der zirkulären, verglichen mit der linearisierten
DNA für beide Transfektionsreagenzien. Die elektronenmikroskopischen Bilder von
Lipofectamine sowie PEI komplexiert mit DNA zeigen, dass die zirkuläre DNA
zufällige, kompakte Kugelformen bildet, während die linearisierte DNA wurmartige
Stränge aufweist. Partikelgröße und -form spielen in der Zellbiologie eine wichtige
Rolle bei der Endozytose und Phagozytose. Die Ergebnisse legen die Vermutung
nahe dass die Form der zu transfizierenden DNA-Transfektions-Komplexen eine
wichtige Rolle einnimmt für einen erfolgreichen Gentransfer.
Für die Entwicklung eines intelligenten Wirkstoffabgabe-Systems für die Gentherapie
wurden zwei kationische Diblock-Kopolymere, die aus primären und tertiären Aminen
bestehen synthetisiert und im Hinblick auf deren DNA-Kondensationseigenschaften,
Morphologie der kondensierten Plasmid-DNA sowie Transfektionseffizienz unter
Verwendung von zwei Zelllinien analysiert. Die Studie bestätigt trotz einer um den
Faktor 10 schwächeren Transfektionseffizienz der primären Amin-DiblockKopolymeren
im Vergleich zu PEI nach 48 h mit zunehmender pDNA Konzentration
eine Bestätigung des Konzepts. Außerdem weisen die primären Amin-Block-
Kopolymere im Vergleich zu den tertiären eine viel stärkere Komplexbildung der DNA
auf - wie transmissions-elektronen- und rasterkraft-mikroskopische Daten ergaben -
als auch eine verbesserte Transfektionseffizienz. Diese physikalischmorphologischem
Erkenntnisse über die Kondensation der primären und tertiären
Amine mit Plasmid-DNA konnten mittels der biologischen Transfektionseffizienzdaten
validiert werden.
Der zweite Teil der experimentellen Arbeit befasst sich mit dem Design sowie der
Charakterisierung von pentablock-basierten Polyplexen für einen gezielten siRNA
Transport. Diese Polyplexe beruhen auf einer Kombination von kationischen
Pentablock-Kopolymeren mit folsäure-funktionalisierten Kopolymeren. Die erreichten
31% Gen-Suppression in einem Krebszellkulturmodell, zeigen das Potenzial des
Wirkstoffabgabesystems in Bezug auf eine Krebstherapie auf. Die Architektur
ermöglicht die Bildung von sehr stabilen Mizellen mit einer Grösse von (21 ± 3) nm in
10 mM PBS Pufferlösung, eine neutrale Oberflächenladung, ausgezeichneten siRNAKondensationseigenschaften,
hervorragender kolloidaler Stabilität in
Zellkulturmedium supplementiert mit 10 % Serum über 24 h, sowie guter
Biokompatibilität aufgrund fehlender erheblicher Zytotoxizität auch nach 48 h
Inkubation in einem Zellkulturmodell. Ferner konnte durch die Einführung eines
liganden-gebundenen Block-Kopolymers der selektive Transport der siRNA
nachgewiesen werden, was zu einer Gen Suppression von 31% gegenüber 8% nicht
funktionalisierter Polyplexen führte. Das in dieser Arbeit eingeführte und
charakterisierte pentablock-basierte Wirkstoffabgabesystem könnte Auswirkungen
auf das Design zukünftiger Wirkstoffabgabesystem haben als auch als eine
potentielle Plattform für in vivo-Krebsgentherapien angewendet werden
Enterprise Risk Management [electronic resource] : Modern Approaches to Balancing Risk and Reward /
No full textThis textbook demonstrates how Enterprise Risk Management creates value in strategic- and decision-making-processes. The author introduces modern approaches to balancing risk and reward based on many examples of medium-sized and large companies from different industries. Since traditional risk management in practice is often an independent stand-alone process with no impact on decision-making processes, it is unable to create value and ties up resources in the company unnecessarily. Herewith, he serves students as well as practitioners with modern approaches that promote a connection between ERM and corporate management. The author demonstrates in a didactically appropriate manner how companies can use ERM in a concrete way to achieve better risk-reward decisions under uncertainty. Furthermore, theoretical and psychological findings relevant to entrepreneurial decision-making situations are incorporated. This textbook has been recommended and developed for university courses in Germany, Austria and Switzerland. Table of Contents Introduction to ERM Countering Biases in Risk Analysis Creating Value through ERM Process Setting up Enterprise Risk Governance Looking at Trends in ERM The Author Professor Dr. Stefan Hunziker is Head of the competence center “Risk and Compliance Management” at Lucerne University of Applied Sciences and Arts. Furthermore, he is the Chairman of the Board of Swiss Enterprise Risk Management Association (SwissERM).Introduction to ERM -- Countering Biases in Risk Analysis -- Creating Value through ERM Process -- Setting up Enterprise Risk Governance -- Looking at Trends in ERM.This textbook demonstrates how Enterprise Risk Management creates value in strategic- and decision-making-processes. The author introduces modern approaches to balancing risk and reward based on many examples of medium-sized and large companies from different industries. Since traditional risk management in practice is often an independent stand-alone process with no impact on decision-making processes, it is unable to create value and ties up resources in the company unnecessarily. Herewith, he serves students as well as practitioners with modern approaches that promote a connection between ERM and corporate management. The author demonstrates in a didactically appropriate manner how companies can use ERM in a concrete way to achieve better risk-reward decisions under uncertainty. Furthermore, theoretical and psychological findings relevant to entrepreneurial decision-making situations are incorporated. This textbook has been recommended and developed for university courses in Germany, Austria and Switzerland. Table of Contents Introduction to ERM Countering Biases in Risk Analysis Creating Value through ERM Process Setting up Enterprise Risk Governance Looking at Trends in ERM The Author Professor Dr. Stefan Hunziker is Head of the competence center “Risk and Compliance Management” at Lucerne University of Applied Sciences and Arts. Furthermore, he is the Chairman of the Board of Swiss Enterprise Risk Management Association (SwissERM)
Tensor B-spline numerical method for PDEs : a high performance approach
No full textSolutions of Partial Differential Equations (PDEs) form the basis of many mathematical models in physics and medicine. In this work, a novel Tensor B-spline methodology for numerical solutions of linear second-order PDEs is proposed. The methodology applies the B-spline signal processing framework and computational tensor algebra in order to construct high-performance numerical solvers for PDEs. The method allows high-order approximations, is mesh-free, matrix-free and computationally and memory efficient.
The first chapter introduces the main ideas of the Tensor B-spline method, depicts the main contributions of the thesis and outlines the thesis structure.
The second chapter provides an introduction to PDEs, reviews the numerical methods for solving PDEs, introduces splines and signal processing techniques with B-splines, and describes tensors and the computational tensor algebra.
The third chapter describes the principles of the Tensor B-spline methodology. The main aspects are 1) discretization of the PDE variational formulation via B-spline representation of the solution, the coefficients, and the source term, 2) introduction to the tensor B-spline kernels, 3) application of tensors and computational tensor algebra to the discretized variational formulation of the PDE, 4) tensor-based analysis of the problem structure, 5) derivation of the efficient computational techniques, and 6) efficient boundary processing and numerical integration procedures.
The fourth chapter describes 1) different computational strategies of the Tensor B-spline solver and an evaluation of their performance, 2) the application of the method to the forward problem of the Optical Diffusion Tomography and an extensive comparison with the state-of-the-art Finite Element Method on synthetic and real medical data, 3) high-performance multicore CPU- and GPU-based implementations, and 4) the solution of large-scale problems on hardware with limited memory resources
Proficiency in cardiopulmonary resuscitation of medical students at graduation : a simulator-based comparison with general practitioners
No full textQUESTION UNDER STUDY: There are no data on the preparedness of medical students at the time of their graduation to handle a cardiac arrest. The aim of the present study was to compare the performance in cardiopulmonary resuscitation of medical students at the time of their graduation with that of experienced general practitioners. METHODS: 24 teams consisting of three medical students and 24 teams consisting of three general practitioners were confronted with a scenario of a simulated witnessed cardiac arrest. Analysis was performed post-hoc using video recordings obtained during the simulation. RESULTS: Medical students diagnosed the cardiac arrest as quickly as general practitioners. Medical students were less likely to call for help in the initial phase of the cardiac arrest (14/24 vs 21/24; P = 0.002); had less hands-on time during the first 180 seconds of the arrest (52 +/- 33 sec vs 105 +/- 39 sec; P >0.0001); delayed the first defibrillation (168 +/- 78 vs 116 +/- 46 sec, P >0.007); and showed less directive leadership (4/24 vs 14/24 teams, P >0.007). The technical quality of cardiopulmonary resuscitation provided by medical students was partly better, but for no parameter worse, than that provided by general practitioners. CONCLUSIONS: When confronted with a cardiac arrest, medical students at the time of their graduation substantially delayed evidence-based life-saving measures like defibrillation and provided only half of the resuscitation support provided by experienced general practitioners. Future research should focus on how to best prepare medical students to handle medical emergencies
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