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Untersuchungen zum thermodynamischen Verhalten des Sauerstoffs in Kupfer-Wismut-Schmelzen bei 1200°C
(1982)
The purpose of the current study in combination with our previous published data (Arampatzis et al., 2007) was to examine the effects of a controlled modulation of strain magnitude and strain frequency applied to the Achilles tendon on the plasticity of tendon mechanical and morphological properties. Eleven male adults (23.9±2.2 yr) participated in the study. The participants exercised one leg at low magnitude tendon strain (2.97±0.47%), and the other leg at high tendon strain magnitude (4.72±1.08%) of similar frequency (0.5 Hz, 1 s loading, 1 s relaxation) and exercise volume (integral of the plantar flexion moment over time) for 14 weeks, 4 days per week, 5 sets per session. The exercise volume was similar to the intervention of our earlier study (0.17 Hz frequency; 3 s loading, 3 s relaxation) allowing a direct comparison of the results. Before and after the intervention ankle joint moment has been measured by a dynamometer, tendon–aponeurosis elongation by ultrasound and cross-sectional area of the Achilles tendon by magnet resonance images (MRI). We found a decrease in strain at a given tendon force, an increase in tendon–aponeurosis stiffness and tendon elastic modulus of the Achilles tendon only in the leg exercised at high strain magnitude. The cross-sectional area (CSA) of the Achilles tendon did not show any statistically significant (P>0.05) differences to the pre-exercise values in both legs. The results indicate a superior improvement in tendon properties (stiffness, elastic modulus and CSA) at the low frequency (0.17 Hz) compared to the high strain frequency (0.5 Hz) protocol. These findings provide evidence that the strain magnitude applied to the Achilles tendon should exceed the value, which occurs during habitual activities to trigger adaptational effects and that higher tendon strain duration per contraction leads to superior tendon adaptational responses.
Venus und Mars
(2021)
Venus und Mars - Mann und Frau. Ein binäres System, welches heutzutage einer ständigen Hinterfragung ausgesetzt ist. Woraus entstand dieses System und wie manipulativ ist das Geschlecht wirklich? Die Pionierwerke der Gender Studies/Queer Studies zeigten auf, dass jeder Mensch sein Geschlecht durch das Imitieren von sozial-gesellschaftlich festgelegten Normen und Werten bildet. Drag-Künstler*innen leben diesen Prozess in einer visuellen Form vor, indem sie Geschlechternormen aufgreifen und sie unabhängig vom biologischen Geschlecht der Darstellenden inszenieren, imitieren, parodieren und neu zusammensetzen. Jede Performance auf den Fotografien greift ebenfalls vorhandene Vorstellungen von Geschlecht auf und interpretiert sie neu: denn Drag kennt kein Original, genauso wenig wie das Geschlecht.
Novel organic membrane-based thin-film microsensors for the determination of heavy metal cations
(2006)
A first step towards the fabrication and electrochemical evaluation of thin-film microsensors based on organic PVC membranes for the determination of Hg(II), Cd(II), Pb(II) and Cu(II) ions in solutions has been realised. The membrane-coating mixture used in the preparation of this new type of microsensors is incorporating PVC as supporting matrix, o-nitrophenyloctylether (o-NPOE) as solvent mediator and a recently synthesized Hg[dimethylglyoxime(phene)]2+ and Bis-(4-hydroxyacetophenone)-ethylenediamine as electroactive materials for Hg(II) and Cd(II), respectively. A set of three commercialised ionophores for Cd(II), Pb(II) and Cu(II) has been also used for comparison. Thin-film microsensors based on these membranes showed a Nernstian response of slope (26-30 mV/dec.) for the respective tested cations. The potentiometric response characteristics (linear range, pH range, detection limit and response time) are comparable with those obtained by conventional membranes as well as coated wire electrodes prepared from the same membrane. The realisation of the new organic membrane-based thin-film microsensors overcomes the problem of an insufficient selectivity of solid-state-based thinfilm sensors.
Microfabrication, characterization and analytical application of a new thin-film silver microsensor
(2009)
One of interesting but not well known water properties is related to appearance of highly ordered structures in response to strong electrical field. In 1893 Sir William Armstrong placed a cotton thread between two wine glasses filled with chemically pure water. When high DC voltage was applied between the glasses, a connection consisting of water formed, producing a "water bridge"
Background
True date palms (Phoenix dactylifera L.) are impressive trees and have served as an indispensable source of food for mankind in tropical and subtropical countries for centuries. The aim of this study is to differentiate date palm tree varieties by analysing leaflet cross sections with technical/optical methods and artificial neural networks (ANN).
Results
Fluorescence microscopy images of leaflet cross sections have been taken from a set of five date palm tree cultivars (Hewlat al Jouf, Khlas, Nabot Soltan, Shishi, Um Raheem). After features extraction from images, the obtained data have been fed in a multilayer perceptron ANN with backpropagation learning algorithm.
Conclusions
Overall, an accurate result in prediction and differentiation of date palm tree cultivars was achieved with average prediction in tenfold cross-validation is 89.1% and reached 100% in one of the best ANN.
This paper presents an approach for reducing the cognitive load for humans working in quality control (QC) for production processes that adhere to the 6σ -methodology. While 100% QC requires every part to be inspected, this task can be reduced when a human-in-the-loop QC process gets supported by an anomaly detection system that only presents those parts for manual inspection that have a significant likelihood of being defective. This approach shows good results when applied to image-based QC for metal textile products.
Prior to immobilization of biomolecules or cells onto biosensor surfaces, the surface must be physically or chemically activated for further functionalization. Organosilanes are a versatile option as they facilitate the immobilization through their terminal groups and also display self-assembly. Incorporating hydroxyl groups is one of the important methods for primary immobilization. This can be done, for example, with oxygen plasma treatment. However, this treatment can affect the performance of the biosensors and this effect is not quite well understood for surface functionalization. In this work, the effect of O2 plasma treatment on EIS sensors was investigated by means of electrochemical characterizations: capacitance–voltage (C–V) and constant capacitance (ConCap) measurements. After O2 plasma treatment, the potential of the EIS sensor dramatically shifts to a more negative value. This was successfully reset by using an annealing process.
Optimization of the immobilization of bacterial spores on glass substrates with organosilanes
(2016)
Spores can be immobilized on biosensors to function as sensitive recognition elements. However, the immobilization can affect the sensitivity and reproducibility of the sensor signal. In this work, three different immobilization strategies with organosilanes were optimized and characterized to immobilize Bacillus atrophaeus spores on glass substrates. Five different silanization parameters were investigated: nature of the solvent, concentration of the silane, silanization time, curing process, and silanization temperature. The resulting silane layers were resistant to a buffer solution (e.g., Ringer solution) with a polysorbate (e.g., Tween®80) and sonication.
In the present work, surface functionalization of different sensor materials was studied. Organosilanes are well known to serve as coupling agent for biomolecules or cells on inorganic materials. 3-aminopropyltriethoxysilane (APTES) was used to attach microbiological spores time to an interdigitated sensor surface. The functionality and physical properties of APTES were studied on isolated sensor materials, namely silicon dioxide (SiO2) and platinum (Pt) as well as the combined material on sensor level. A predominant immobilization of spores could be demonstrated on SiO2 surfaces. Additionally, the impedance signal of APTES-functionalized biosensor chips has been investigated.
A microscopic photometric method for measuring erythrocyte deformability. Artmann, Gerhard Michael
(1986)
Tests with palm tree leaves have just started yet and scan data are in the process to be analyzed. The final goal of future project for palm tree gender and species recognition will be to develop optical scanning technology to be applied to date palm tree leaves for in–situ screening purposes. Depending on the software used and the particular requirements of the users the technology potentially shall be able to identify palm tree diseases, palm tree gender, and species of young date palm trees by scanning leaves.
The invention pertains to a CellDrum electrode arrangement for measuring mechanical stress, comprising a mechanical holder (1 ) and a non-conductive membrane (4), whereby the membrane (4) is at least partially fixed at its circumference to the mechanical holder (1), keeping it in place when the membrane (4) may bend due to forces acting on the membrane (4), the mechanical holder (1) and the membrane (4) forming a container, whereby the membrane (1) within the container comprises an cell- membrane compound layer or biological material (3) adhered to the deformable membrane 4 which in response to stimulation by an agent may exert mechanical stress to the membrane (4) such that the membrane bending stage changes whereby the container may be filled with an electrolyte, whereby an electric contact (2) is arranged allowing to contact said electrolyte when filled into to the container, whereby within a predefined geometry to the fixing of the membrane (4) an electrode (7) is arranged, whereby the electrode (7) is electrically insulated with respect to the electric contact (2) as well as said electrolyte, whereby mechanical stress due to an agent may be measured as a change in capacitance.
Mechanical forces/tensile stresses are critical determinants of cellular growth, differentiation and migration patterns in health and disease. The innovative “CellDrum technology” was designed for measuring mechanical tensile stress of cultured cell monolayers/thin tissue constructs routinely. These are cultivated on very thin silicone membranes in the so-called CellDrum. The cell layers adhere firmly to the membrane and thus transmit the cell forces generated. A CellDrum consists of a cylinder which is sealed from below with a 4 μm thick, biocompatible, functionalized silicone membrane. The weight of cell culture medium bulbs the membrane out downwards. Membrane indentation is measured. When cells contract due to drug action, membrane, cells and medium are lifted upwards. The induced indentation changes allow for lateral drug induced mechanical tension quantification of the micro-tissues. With hiPS-induced (human) Cardiomyocytes (CM) the CellDrum opens new perspectives of individualized cardiac drug testing. Here, monolayers of self-beating hiPS-CMs were grown in CellDrums. Rhythmic contractions of the hiPS-cells induce membrane up-and-down deflections. The recorded cycles allow for single beat amplitude, single beat duration, integration of the single beat amplitude over the beat time and frequency analysis. Dose effects of agonists and antagonists acting on Ca2+ channels were sensitively and highly reproducibly observed. Data were consistent with published reference data as far as they were available. The combination of the CellDrum technology with hiPS-Cardiomyocytes offers a fast, facile and precise system for pharmacological and toxicological studies. It allows new preclinical basic as well as applied research in pharmacolgy and toxicology.
A second-order L-stable exponential time-differencing (ETD) method is developed by combining an ETD scheme with approximating the matrix exponentials by rational functions having real distinct poles (RDP), together with a dimensional splitting integrating factor technique. A variety of non-linear reaction-diffusion equations in two and three dimensions with either Dirichlet, Neumann, or periodic boundary conditions are solved with this scheme and shown to outperform a variety of other second-order implicit-explicit schemes. An additional performance boost is gained through further use of basic parallelization techniques.
Background: Architectural representation, nurtured by the interaction between design thinking and design action, is inherently multi-layered. However, the representation object cannot always reflect these layers. Therefore, it is claimed that these reflections and layerings can gain visibility through ‘performativity in personal knowledge’, which basically has a performative character. The specific layers of representation produced during the performativity in personal knowledge permit insights about the ‘personal way of designing’ [1]. Therefore, the question, ‘how can these layered drawings be decomposed to understand the personal way of designing’, can be defined as the beginning of the study. On the other hand, performativity in personal knowledge in architectural design is handled through the relationship between explicit and tacit knowledge and representational and non-representational theory. To discuss the practical dimension of these theoretical relations, Zvi Hecker's drawing of the Heinz-Galinski-School is examined as an example. The study aims to understand the relationships between the layers by decomposing a layered drawing analytically in order to exemplify personal ways of designing.
Methods: The study is based on qualitative research methodologies. First, a model has been formed through theoretical readings to discuss the performativity in personal knowledge. This model is used to understand the layered representations and to research the personal way of designing. Thus, one drawing of Hecker’s Heinz-Galinski-School project is chosen. Second, its layers are decomposed to detect and analyze diverse objects, which hint to different types of design tools and their application. Third, Zvi Hecker’s statements of the design process are explained through the interview data [2] and other sources. The obtained data are compared with each other.
Results: By decomposing the drawing, eleven layers are defined. These layers are used to understand the relation between the design idea and its representation. They can also be thought of as a reading system. In other words, a method to discuss Hecker’s performativity in personal knowledge is developed. Furthermore, the layers and their interconnections are described in relation to Zvi Hecker’s personal way of designing.
Conclusions: It can be said that layered representations, which are associated with the multilayered structure of performativity in personal knowledge, form the personal way of designing.
GummiQs Reisen
(2022)
Dieser Film ist ein Trailer zur Mini-Serie GummiQs Reisen, welche von den fantastischen Abenteuern der Entdeckerinnen GummiQ und Kreska Krähenschreck erzählt.
Gemeinsam erkunden sie auf ihrem Kahn, der Kaleidoskop?, eine lebensfrohe Ozeanwelt, die mit winzigen, einzigartigen Inseln gespickt ist. Im Gegensatz zur jungen GummiQ, die zum ersten Mal verreist, ist Kreska schon eine erfahrene Seefahrerin und wird GummiQs Kapitänin und Mentorin. Sie leitet GummiQ nicht nur durch das Meer, sondern auch durch philosophische Gefilde. Denn jede Insel birgt ein eigenes soziales Dilemma, welches das ungewöhnliche Paar immer wieder dazu herausfordert, die Welt zu hinterfragen, von der sie glaubten, sie zu kennen.
Gesprochen von Marianne Graffam. Musik von Eric Michels.
Geschrieben und produziert von Miriam De Stefano und Mara Asmuth.
The esophageal Doppler monitor (EDM) is a minimally-invasive hemodynamic device which evaluates both cardiac output (CO), and fluid status, by estimating stroke volume (SV) and calculating heart rate (HR). The measurement of these parameters is based upon a continuous and accurate approximation of distal thoracic aortic blood flow. Furthermore, the peak velocity (PV) and mean acceleration (MA), of aortic blood flow at this anatomic location, are also determined by the EDM. The purpose of this preliminary report is to examine additional clinical hemodynamic calculations of: compliance (C), kinetic energy (KE), force (F), and afterload (TSVRi). These data were derived using both velocity-based measurements, provided by the EDM, as well as other contemporaneous physiologic parameters. Data were obtained from anesthetized patients undergoing surgery or who were in a critical care unit. A graphical inspection of these measurements is presented and discussed with respect to each patient’s clinical situation. When normalized to each of their initial values, F and KE both consistently demonstrated more discriminative power than either PV or MA. The EDM offers additional applications for hemodynamic monitoring. Further research regarding the accuracy, utility, and limitations of these parameters is therefore indicated.
Mit der App »atmosphere« soll die Veranstaltungsbranche in die digitale Welt eingeführt werden. Insbesondere nach der COVID–19 Pandemie bedarf es einer Erneuerung in dem Sektor für Liveunterhaltung. Die Auswirkungen der Krise auf diesen Wirtschaftszweig waren enorm und auch das Publikum litt unter der Situation. Die Mission von »atmosphere« besteht darin, den Zugang zu Veranstaltungen, Konzerten, Stand–Up–Auftritten und Festivals zu vereinfachen. Hierbei werden die Bereiche der Planung und der Buchung komplett in dem Service der App abgedeckt und die digitale Teilnahme an einem Event ermöglicht. Dies bietet neue Möglichkeiten für die Zukunft und dient als Alternative für Krisen. Insgesamt soll der Service den Zugang vereinfachen, die aufwendigen Planungsschritte reduzieren und die Knackpunkte in der Nutzererfahrung digitalisieren.