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Seit einigen Jahren beschäftigen sich immer mehr Autor*innen mit der Frage, welche Handreichungen Mitarbeitende im Gesundheitssystem brauchen, um adäquater auf die Bedürfnisse älterer LGBTQI* Personen einzugehen, deren (pflegerische) Anliegen nicht erkannt werden, von schwer zu überwindenden Barrieren im Gesundheitssystem berichten und die sich diskriminiert fühlen. Der Fokus der Publikationen liegt auf der sexuellen Orientierung und / oder der Genderidentität, einem Teilaspekt der Identität einer Person. Je nach Kontext und Personen sind andere Teilidentitäten, wie z.B. Familienstatus, Alter, Ethnizität, Teilhabe an sozialen Gruppen unterschiedlich stark berücksichtigt. In einer qualitativen Studie wurden, unter Integration der autoethnographischen Methode, acht Männer zwischen 53 und 75 Jahren aus den Niederlanden und Deutschland in autobiografischen-narrativen Interviews befragt, inwiefern die Coronapandemie ihre Vorstellungen vom gesunden Altern verändert hat. Alle Männer hatten komplexe Biografien, gekennzeichnet von Partnerverlust, Arbeitslosigkeit, Altersfragen, familiären und gesundheitlichen Herausforderungen neben anderen identitätsstiftenden Faktoren. Aber alle identifizierten sich seit ihrer Jugend mit ihrer sexuellen oder Genderidentität, hatten aus vielen Krisen gelernt und sorgten mit einem für sich klaren Management, dass sie auch im Alter gesund bleiben würden – Autonomie stand hoch im Kurs! Die Person nicht nur auf die Zugehörigkeit zur LGBTQI* Gruppe zu reduzieren, sondern in ihrer gesamten Identität in den Gesundheitseinrichtungen zu berücksichtigen kennzeichnet eine adäquate Pflege.
Zeigen, nicht erklären!
(2020)
Medien sind während der Covid-Pandemie in besonderem Maße gefordert, komplexe Sachverhalte, wie Inzidenzen und exponentielles Wachstum einfach zu erklären. Informationsgrafiken sind dazu bestens geeignet, erfordern allerdings hohe Kompetenz in der Erstellung. Dieser Artikel plädiert für die Einführung eines eigenen journalistischen Genres, nämlich des visuellen Journalismus.
Wirtschaftsethik
(2020)
Wirtschaftliche und ethische Handlungen sind zugleich realisierbar, wenn zwischen einer einrahmenden Wirtschaftsordnung (Spielregeln) und einzelnen Handlungen (Spielzügen) unterschieden wird. Das wirtschaftliche Tun und Unterlassen wird dann in den Spielzügen und die Ethik über die Spielregeln realisierbar. Die Gültigkeit einer Wirtschaftsordnung setzt einen allgemeinen Konsens über die Spielregeln und die Durchsetzungsinstanzen (z. B: Justiz oder Kartellamt) voraus. Dann regelt sie den Wettbewerb und nötigt Anbieter, sich an den Interessen der Nachfrager zu orientieren und dabei auf einen effizienten Ressourceneinsatz zu achten. So erfolgt das individuelle Handeln der Marktteilnehmer in der einrahmenden Wirtschaftsordnung mit den darin befindlichen Anreizen, daher spricht man von einer Anreizethik. Mit ihr werden wirtschaftliche und ethische Handlungen zugleich realisierbar.
This chapter is about school suspension through a social work lens. Young people like Martin require the collective to belong, to be a member of a group, to realise their social needs. This is the basic requirement of human mental and social stability. Suspension stands in opposition because it legitimises social exclusion and disregards the linkage between the individual and collective (Bunge 2003). This chapter advocates for a whole systems approach to tackle social problems and develop sustainable interventions that facilitate young peoples’ needs realisation at school.
Greater specific energy densities in lithium-ion batteries can be achieved by using three-dimensional (3D) porous current collectors, which allow for greater areal mass loadings of the electroactive material. In this paper, we present the use of embroidered current collectors for the preparation of thick, pouch-type Li-ion batteries. Experiments were performed on LiFePO 4 (LFP) water-based slurries using styrene-butadiene rubber (SBR) as binder and sodium carboxymethyl cellulose (CMC) as thickener, and formulations of different rheological characteristics were investigated. The electrochemical performance (cyclic voltammetry, rate capability) and morphological characteristics of the LFP half-pouch cells (X-ray micro computed tomography and scanning electron microscopy) were compared between the formulations. An optimum electrode formulation was identified, and a mechanism is proposed to explain differences between the formulations. With the optimum electrode formulation, 350 µm casted electrodes with high mechanical stability were achieved. Electrodes exhibited 4–6 times greater areal mass loadings (4–6 mAh cm −2 ) and 50% greater electroactive material weight than with foils. In tests of half- and full-pouch embroidered cells, a 50% capacity utilization at 1C-rate and 11% at 2C-rate were observed, with a full recovery at C/5-rate. The cycling stability was also maintained over 55 cycles.
Towards a strategic management framework for engineering of organizational robustness and resilience
(2020)
The Convention on the Rights of the Child (CRC) is a human rights framework in the context of multi-level governance child protection policies central to social work education and practice (United Nations, 1989). In line with this statement, children’s rights-based education introduces undergraduate social work students to the principles of the CRC, namely participation, protection, harm prevention and provision, to facilitate knowledge acquisition by building core competencies for critical practice (IFSW, 2002). It equips social workers with analytical and advocacy skills that foster critical thinking and creativity in the juxtaposition between child protection, autonomy and self-determination.
This chapter provides insights for social work education to locate and analyse the underlying casualties of social problems using a problem and resource framework, the w-questions (Geiser, 2015). The framework is used to develop theory driven social work interventions as illustrated against the backdrop the anonymised case study, Amira, an accompanied child asylum seeker in Austria (Fritsche, Glawischnig, & Wolfsegg, 2019). Correspondingly, CRC is addressed along a continuum between human needs fulfilment and human right entitlements (Obrecht, 2009; IFSW, 2002; Ife, 2012). The concept of need is understood as tension in our concrete biological and psychological bio-values and states (Obrecht, 2009, p. 27). The assertion is that when children lack support or are obstructed from achieving their equal right to education due to social, cultural or economic barriers, this exacerbates social marginalisation because it deprives them of membership in the school social system. Social marginalisation thwarts the fulfilment of needs and weakens social cohesion by causing alienation and anomie (Mayrhofer, 2015). The tentative conclusion is that knowledge and practice models that link human needs and children’s rights equip social workers with the expertise to reduce children’s vulnerability whilst strengthening their protection, autonomy and self-determination.
For a given set of banks, how big can losses in bad economic or financial scenarios possibly get, and what are these bad scenarios? These are the two central questions of stress tests for banks and the banking system. Current stress tests select stress scenarios in a way which might leave aside many dangerous scenarios and thus create an illusion of safety; and which might consider highly implausible scenarios and thus trigger a false alarm. We show how to select scenarios systematically for a banking system in a context of multiple credit exposures. We demonstrate the application of our method in an example on the Spanish and Italian residential real estate exposures of European banks. Compared to the EBA 2016 stress test our method produces scenarios which are equally plausible as the EBA stress scenario but yield considerably worse system wide losses.
With the emergence of the recent Industry 4.0 movement, data integration is now also being driven along the production line, made possible primarily by the use of established concepts of intelligent supply chains, such as the digital avatars. Digital avatars – sometimes also called Digital Twins or more broadly Cyber-Physical Systems (CPS) – are already successfully used in holistic systems for intelligent transport ecosystems, similar to the use of Big Data and artificial intelligence technologies interwoven with modern production and supply chains. The goal of this paper is to describe how data from interwoven, autonomous and intelligent supply chains can be integrated into the diverse data ecosystems of the Industry 4.0, influenced by a multitude of data exchange formats and varied data schemas. In this paper, we describe how a framework for supporting SMEs was established in the Lake Constance region and describe a demonstrator sprung from the framework. The demonstrator project’s goal is to exhibit and compare two different approaches towards optimisation of manufacturing lines. The first approach is based upon static optimisation of production demand, i.e. exact or heuristic algorithms are used to plan and optimise the assignment of orders to individual machines. In the second scenario, we use real-time situational awareness – implemented as digital avatar – to assign local intelligence to jobs and raw materials in order to compare the results to the traditional planning methods of scenario one. The results are generated using event-discrete simulation and are compared to common (heuristic) job scheduling algorithms.
Post-operative isoflurane has been observed to be present in the end-tidal breath of patients who have undergone major surgery, for several weeks after the surgical procedures. A major new noncontrolled, non-randomized, and open-label approved study will recruit patients undergoing various surgeries under different inhalation anaesthetics, with two key objectives, namely to record the washout characteristics following surgery, and to investigate the influence of a patient’s health and the duration and type of surgery on elimination. In preparation for this breath study using proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS), it is important to identify first the analytical product ions that need to be monitored and under what operating conditions. In this first paper of this new research programme, we present extensive PTR-TOF-MS studies of three major
anaesthetics used worldwide, desflurane (CF3CHFOCHF2), sevoflurane ((CF3)2CHOCH2F), and isoflurane (CF3CHClOCHF2) and a fourth one, which is used less extensively, enflurane (CHF2OCF2CHFCl), but is of interest because it is an isomer of isoflurane. Product ions are identified as a function of reduced electric field (E/N) over the range of approximately 80 Td to 210 Td, and the effects of operating the drift tube under ‘normal’ or ‘humid’ conditions on the intensities of the product ions are presented. To aid in the analyses, density functional theory (DFT) calculations of the proton affinities and the gas-phase basicities of the anaesthetics have been determined. Calculated energies for the ion-molecule reaction pathways leading to key product ions, identified as ideal for monitoring the inhalation anaesthetics in breath with a high sensitivity and selectivity, are also presented.
Spielregeln und Spielzüge
(2020)
Die Gültigkeit einer Wirtschaftsordnung (Spielregeln) verlangt den Beteiligten einen allgemeinen Konsens, der sich auch auf die Durchsetzungsinstanzen (Schiedsrichter) bezieht. Es fragt sich, auf welcher Basis dieser Konsens über die Geltung von Spielregeln, Spielzügen und regelkonform sanktionierenden Schiedsrichtern beruht und gibt es dafür benötige Vorbedingungen?
The importance of Agent-Based Simulation (ABS) as scientific method to generate data for scientific models in general and for informed policy decisions in particular has been widely recognised. However, the important technique of code testing of implementations like unit testing has not generated much research interested so far. As a possible solution, in previous work we have explored the conceptual use of property-based testing. In this code testing method, model specifications and invariants are expressed directly in code and tested through automated and randomised test data generation. This paper expands on our previous work and explores how to use property-based testing on a technical level to encode and test specifications of ABS. As use case the simple agent-based SIR model is used, where it is shown how to test agent behaviour, transition probabilities and model invariants. The outcome are specifications expressed directly in code, which relate whole classes of random input to expected classes of output. During test execution, random test data is generated automatically, potentially covering the equivalent of thousands of unit tests, run within seconds on modern hardware. This makes property-based testing in the context of ABS strictly more powerful than unit testing, as it is a much more natural fit due to its stochastic nature.
Sensemaking
(2020)
Maßnahmen zur Planung, zum Aufbau und zur Steuerung einer Wertschöpfungsarchitektur entfalten ihre Wirkung, wenn sie kontextsensitiv entwickelt und umgesetzt werden. Zu diesem Kontext gehören Strukturen und Prozesse der geplanren Vorgehensweise, ermittelbare Daten und Informationen über das eigene Tun sowie Erwartungen und Verhaltensweisen aller Beteiligten. Im Kern der Bemühungen sollte die Mitgestaltung kommunikativer Prozesse der gemeinsamen Verständigung sein, denn ihre Resonanzen sind die Bezugspunkte für das weitere Tun. Daher gilt: Der betriebswirtschaftliche Erfolg wird maßgeblich geprägt durch die Qualität der Verständigung.
Wir untersuchen Gemeinsamkeiten und Unterschiede partizipativer Projekte auf Gemeindeebene in der Bodenseeregion. Ziel dabei ist es, einerseits Chancen und Stolpersteine von partizipativen Projekten für Gemeinden zu identifizieren. Andererseits entwickeln wir den Resilienzbegriff aus Psychologie und BWL weiter für Gemeinden und fragen uns, wie Partizipation die Resilienz einer Gemeinde beeinflusst.
Eine ergebnisoffene, konstruktiv-kritische Reflexion der zu verantwortenden Wertschöpfung durch verschiedene Beobachter mit den unterschiedlichsten Prägungen ist nicht voraussetzungslos zu haben. Die beteiligten Personen (Stelleninhaber in einer Position mit einer Funktion) sind gewohnt, mit der „Brille“ ihrer Fachdisziplin, ihrer Fachabteilung oder ihres Verantwortungsbereiches die jeweils zu verantwortende Wertschöpfung zu betrachten. Die zu bearbeitenden Problemstellungen hingegen beachten keinerlei Grenzen von Fachdisziplinen, Fachabteilungen oder Verantwortungsbereichen.
Quasilineare Tauchankerspule
(2020)
Probemlösung
(2020)
Der Prozess der Problemlösung wird durch aufeinander verweisende, anschlussfähige Kommunikationen zusammengehalten. Mit Kommunikationen wird ein gemeinsames Verständnis über das Gegebene und über das Gewollte erarbeitet (Sensemaking). Das Resultat des Kommunizierens erlangt durch die Abgabe von Selbstverpflichtungen (Commitments) ihre kollektive Verbindlichkeit.
Praxisorientierte BWL
(2020)
Die Betriebswirtschaftslehre ist eine praxisorientierte Wissenschaft, der es um das nachvollziehbare Ableiten theoretischer Erkenntnisse und das Herleiten praxistauglicher Gestaltungsvorschläge für die betriebliche Praxis geht. Zu erarbeiten sind möglichst allgemein anwendbare Methoden, Instrumente oder Konzepte und nicht nur Lösungsvorschläge für eine einzelne Problematik. Theorie ist dabei keinesfalls das Gegenteil von Praxis, vielmehr sind Theorie und Praxis zwei sich gegenseitig bedingende Polare einer tragfähigen Berufsqualifizierung („Employability“).
Praxis versus Theorie
(2020)
Praktisches Tun ist auch ein Ausfluss vorherigen Denkens. Abstrahierende Reflexion bezieht sich auch auf das konkrete Umsetzen in der Praxis. Erfolgsversprechend ist also eine reflektierte Handlungsorientierung, die gegebene Rahmenbedingungen beachtet und zweckdienlich ist. Daher sind Praxis und Theorie siamesische Zwillinge, die stets zusammen zu Besuch kommen.
Blood flow and ventilatory flow strongly influence the concentrations of volatile organic compounds (VOCs) in exhaled breath. The physicochemical properties of a compound (e.g., water solubility) additionally determine if the concentration of the compound in breath reflects the alveolar concentration, the concentration in the upper airways, or a mixture of both. Mathematical modeling based on mass balance equations helps to understand how measured breath concentrations are related to their corresponding blood concentrations and physiological parameters, such as metabolic rates and endogenous production rates. In addition, the influence of inhaled compounds on their exhaled concentrations can be quantified and appropriate correction formulas can be derived. Isoprene and acetone, two endogenous VOCs with very different water solubility, have been modeled to explain the essential features of their behavior in breath. This chapter introduces the theory of physiological modeling of exhaled VOCs, with examples of isoprene and acetone.
Organisation als Form
(2020)
In Diskursen liegen viele Missverständnisse darin begründet, dass die Diskursteilnehmer bei der Versprachlichung ihrer Gedanken ineinander verschachtelte Bezeichnungen und Unterscheidungen benutzen. Jede Unterscheidung wird zu einer Kontextur im Kontext weiterer Kontexturen. Was das bedeutet, wird hier anhand des Phänomens mit Namen Organisation skizziert.
Background: The development of mobile interventions for noncommunicable diseases has increased in recent years. However, there is a dearth of apps for patients with peripheral arterial disease (PAD), who frequently have an impaired ability to walk.
Objective: Using a patient-centered approach for the development of mobile interventions, we aim to describe the needs and requirements of patients with PAD regarding the overall care situation and the use of mobile interventions to perform supervised exercise therapy (SET).
Methods: A questionnaire survey was conducted in addition to a clinical examination at the vascular outpatient clinic of the West-German Heart and Vascular Center of the University Clinic Essen in Germany. Patients with diagnosed PAD were asked to answer questions on sociodemographic characteristics, PAD-related need for support, satisfaction with their health care situation, smartphone and app use, and requirements for the design of mobile interventions to support SET.
Results: Overall, a need for better support of patients with diagnosed PAD was identified. In total, 59.2% (n=180) expressed their desire for more support for their disease. Patients (n=304) had a mean age of 67 years and half of them (n=157, 51.6%) were smartphone users. We noted an interest in smartphone-supported SET, even for people who did not currently use a smartphone. “Information,” “feedback,” “choosing goals,” and “interaction with physicians and therapists” were rated the most relevant components of a potential app.
Conclusions: A need for the support of patients with PAD was determined. This was particularly evident with regard to disease literacy and the performance of SET. Based on a detailed description of patient characteristics, proposals for the design of mobile interventions adapted to the needs and requirements of patients can be derived.
Clathrate hydrates, or hydrates for short, are inclusion compounds in which water molecules form a hydrogen-bonded host lattice that accommodates the guest molecules. While vast amounts of hydrates are known to exist in seafloor sediments and in the permafrost on Earth, these occurrences might be dwarfed by the amounts of hydrates occurring in space and on celestial bodies. Since methane is the primary guest molecule in most of the natural occurrences on Earth, hydrates are considered a promising source of energy. Moreover, the ability of one volume of hydrate to store about 170 volumes of gas, make hydrates a promising functional material for various industrial applications. While the static properties of hydrates are reasonably well known, the dynamics of hydrate formation and decomposition are insufficiently understood. For instance, the stochastic period of hydrate nucleation, the memory effect, and the self-preservation phenomenon complicate the development of predictive models of hydrate dynamics. Additionally, the influence of meso- and macroscopic defects as well as the roles of mass and heat transport on different length scales remain to be clarified.
Due to its non-invasive and non-destructive nature and the high spatial resolution of approx. 1µm or even less, micro-computed X-ray attenuation tomography ( µCT ) seems to be the perfect method for the study of the evolving structures of forming or decomposing hydrates on the meso- and macroscopic length scale. However, for the naturally occurring hydrates of low atomic number guests the contrast between hydrate, ice, and liquid water is typically very weak because of similar X-ray attenuation coefficients. So far, good contrast was only restricted to synchrotron beamline experiments which utilize the phase information of monochromatic X-rays.
In this thesis it is shown that with the help of a newly developed sample cell, a contrast between the hydrate and the ice phase sufficiently good for the reliable segmentation of the materials can also be achieved in conventional tube-based µCT. An accurate pressure and temperature management, i.e., the added functionality of the cell, further allows for cross-correlation of structural and thermodynamic data. The capability of this µCT setup is demonstrated in a series of studies on the formation and decomposition of hydrates which yield new insights for the development of a novel route to hydrate synthesis. At last, this thesis points towards possibilities how better models of hydrate formation and decomposition can be developed with the aid of µCT and computer simulations.
Steigende Komplexität von Geschäftsmodellen und in der Niedrigzinsphase stets zulegende Renditeerwartungen an kapitalmarktorientierte Unternehmen führen dazu, dass sich deren Berichterstattung anpasst. Unter anderem ist eine verstärkte Verbreitung und Anwendung von Key Performance Indicators (alternative Führungsgrößen) in der Praxis zu beobachten. Wenigen, zwar prägnanten, aber eben nicht einheitlich definierten oder gar nach geltenden Rechnungslegungsnormen objektiv zu gewinnende Messgrößen kommt eine gesteigerte Bedeutung im externen Berichtswesen zu. Der Beitrag liefert eine Bestandesaufnahme der meist verwendeten Key Performance Indicators in der Praxis in Deutschland, in Österreich und in der Schweiz.
Kalkül der Form
(2020)
Der Kalkül von Spencer-Brown dokumentiert mit der Form der Unterscheidung in logisch-mathematischer Weise das Benennen eines Beobachtungsobjektes in Abhängigkeit von der zuvor getätigten Unterscheidung des Beobachters. Diese Unterscheidung ist weder Objekt noch Relation: Sie ist eine Operation, die zugleich Operand und Operator ist!
Investigation of non-uniformly emitting optical fiber diffusers on the light distribution in tissue
(2020)
Wer wünscht ihn nicht: den intelligenten, effizienten und wirtschaftlichen Herstellungsprozess? Viele Firmen setzten aktuell auf die Digitalisierung und verbessern so die eigene sowie die mit externen Stellen vernetzte Produktion. Die Digitalisierung bringt einerseits Fortschritt, zeigt aber auch die zunehmende Komplexität der heutigen Produktionsnetzwerke auf. Zahlreiche Entscheidungen sind zu fällen, um einen effizienten und sicheren Austausch mit verschiedenen Betrieben zu gewährleisten.
Ein Blick auf vorhandene Modelle kann da weiterhelfen: Im Projekt i4Production des IBH-Labs KMUdigital haben Teams an drei Standorten in den drei Nachbarländern Deutschland (HTWG Konstanz), Österreich (FH Vorarlberg) und der Schweiz (NTB Buchs, RhySearch) an einer vernetzten Prozesslandschaft gearbeitet. In einem gemeinsamen, standardisierten Automatisierungskonzept wird in der international vernetzten Modellfabrik ein cyberphysisches System (CPS) in Form eines kundenindividualisierten Modellfahrzeuges produziert, das durch den Kunden in diversen Varianten zusammengestellt oder individuell konstruiert werden kann. Die dezentrale Produktion erlaubt eine Datenweitergabe über die Landesgrenzen in Echtzeit und bildet die Simulation eines länderübergreifenden Business-Eco-Systems ab.
Die Erkenntnisse des Projekts i4Production zeigen wie in kleineren und mittleren Unternehmen (KMU) eine verteilte Produktion, inklusive der Einbindung von Mitarbeitenden und Kunden in eine digitalisierte, hochautomatisierte und kundenindividuelle Produktion, organisiert werden kann.
Für Unternehmen wird diese Industrie 4.0-Prozesslandschaft als Modell für die eigene Fertigung in dem neu aufgebauten CNC Präzisionsfertigungslabor „Werkstatt4“ bei RhySearch öffentlich zur Verfügung gestellt. Die „Werkstatt4“ bietet KMU ein digitales Prozessumfeld, in dem getestet werden kann, mit welchen Maßnahmen der eingangs gestellte Wunsch zur optimierten Herstellung, seinen Weg in die Realität finden kann.
Im Folgenden stellen wir Ihnen das Konzept der internationalen Musterfabrik i4Production, die diversen Arbeitsschritte an den beteiligten Hochschulen sowie die wichtigsten Erkenntnisse für KMU der Bodenseeregion vor. Gerne unterstützen wir Sie bei der Gestaltung des Wandels hin zum Unternehmen 4.0: Sprechen Sie uns an.
Electric cell-substrate impedance spectroscopy (ECIS) enables non-invasive and continuous read-out of electrical parameters of living tissue. The aim of the current study was to investigate the performance of interdigitated sensors with 50 μm electrode width and 50 μm inter-electrode distance made of gold, aluminium, and titanium for monitoring the barrier properties of epithelial cells in tissue culture. At first, the measurement performance of the photolithographic fabricated sensors was characterized by defined reference electrolytes. The sensors were used to monitor the electrical properties of two adherent epithelial barrier tissue models: renal proximal tubular LLC-PK1 cells, representing a normal functional transporting epithelium, and human cervical cancer-derived HeLa cells, forming non-transporting cancerous epithelial tissue. Then, the impedance spectra obtained were analysed by numerically fitting the parameters of the two different models to the measured impedance spectrum. Aluminium sensors proved to be as sensitive and consistent in repeated online-recordings for continuous cell growth and differentiation monitoring assensors made of gold, the standard electrode material. Titanium electrodes exhibited an elevated intrinsic ohmic resistance incomparison to gold reflecting its lower electric conductivity. Analysis of impedance spectra through applying models and numerical data fitting enabled the detailed investigation of the development and properties of a functional transporting epithelial tissue using either gold or aluminium sensors. The result of the data obtained, supports the consideration of aluminium and titanium sensor materials as potential alternatives to gold sensors for advanced application of ECIS spectroscopy.
The humidification-dehumidification process (HDH) for desalination is a promising technology to address water scarcity issues in rural regions. However, a low humidifier efficiency is a weakness of the process. Bubble column humidifiers (BCH) are promising for HDH, as they provide enhanced heat and mass transfer and have low maintenance requirements. Previous studies of HDH-systems with BCHs draw different conclusions regarding the impact of superficial air velocity and liquid height on the humidification. Furthermore, the impact of flow characteristics has never been investigated systematically at all. In this study, an optimized BCH test setup that allows for optical analysis of the humidifier is used and evaluated. Our test setup is validated, since the influence of water temperature on the humidification, which is exponential, is reproduced. Measurements with seawater show that the normalised system productivity is increased by about 56 % with an increase in superficial air velocity from 0.5 to 5 cm/s. Furthermore, the system productivity is increased by around 29 % with an increase in liquid height from 60 to 378 mm. While the impact of superficial air velocity can be traced back to temperature changes at the humidifier and dehumidifier outlets, the impact of liquid height is shown to be caused by a smaller heat loss surface in the humidifier with an increase in liquid height. For the impact of sieve plate orifice diameter, a clear influence on the humidification is not apparent, this parameter needs to be investigated further. Finally, our new test setup allows for analysing the humidification of air (1) in a systematic way, (2) in relevant measurement ranges and (3) in comparison with optical analyses of the flow characteristics.
Over the last years, polymers have gained great attention as substrate material, because of the possibility to produce low-cost sensors in a high-throughput manner or for rapid prototyping and the wide variety of polymeric materials available with different features (like transparency, flexibility, stretchability, etc.). For almost all biosensing applications, the interaction between biomolecules (for example, antibodies, proteins or enzymes) and the employed substrate surface is highly important. In order to realize an effective biomolecule immobilization on polymers, different surface activation techniques, including chemical and physical methods, exist. Among them, plasma treatment offers an easy, fast and effective activation of the surfaces by micro/nanotexturing and generating functional groups (including carboxylic acids, amines, esters, aldehydes or hydroxyl groups). Hence, here we present a systematic and comprehensive plasma activation study of various polymeric surfaces by optimizing different parameters, including power, time, substrate temperature and gas composition. Thereby, the highest immobilization efficiency along with a homogenous biomolecule distribution is achieved with a 5-min plasma treatment under a gas composition of 50% oxygen and nitrogen, at a power of 1000 W and a substrate temperature of 80 C. These results are also confirmed by different surface characterization methods, including SEM, XPS and contact angle measurements.
Real-time measurements of the differences in inhaled and exhaled, unlabeled and fully deuterated acetone concentration levels, at rest and during exercise, have been conducted using proton transfer reaction mass spectrometry. A novel approach to continuously differentiate between the inhaled and exhaled breath acetone concentration signals is used. This leads to unprecedented fine grained data of inhaled and exhaled concentrations. The experimental results obtained are compared with those predicted using a simple three compartment model that theoretically describes the influence of inhaled concentrations on exhaled breath concentrations for volatile organic compounds with high blood:air partition coefficients, and hence is appropriate for acetone. An agreement between the predicted and observed concentrations is obtained. Our results highlight that the influence of the upper airways cannot be neglected for volatiles with high blood:air partition coefficients, i.e. highly water soluble volatiles.