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When it comes to improving the health of the general population, mHealth technologies with self-monitoring and intervention components hold a lot of promise. We argue, however, that due to various factors such as access, targeting, personal resources or incentives, self-monitoring applications run the risk of increasing health inequalities, thereby creating a problem of social justice. We review empirical evidence for “intervention-generated” inequalities, present arguments that self-monitoring applications are still morally acceptable, and develop approaches to avoid the promotion of health inequalities through self-monitoring applications.
Background: Peripheral arterial disease (PAD) is a common and severe disease with a highly increased cardiovascular morbidity and mortality. Through the circulatory disorder and the linked undersupply of oxygen carriers in the lower limbs, the ongoing decrease of the pain-free walking distance occurs with a significant reduction in patients’ quality of life. Studies including activity monitoring for patients with PAD are rare and digital support to increase activity via mobile health technologies is mainly targeted at patients with cardiovascular disease in general. The special requirement of patients with PAD is the need to reach a certain pain level to improve the pain-free walking distance. Unfortunately, both poor adherence and availability of institutional resources are major problems in patient-centered care.
Objective: The objective of this trackPAD pilot study is to evaluate the feasibility of a mobile phone–based self tracking app to promote physical activity and supervised exercise therapy (SET) in particular. We also aim for a subsequent patient centered adjustment of the app prototype based on the results of the app evaluation and process evaluation.
Methods: This study was designed as a closed user group trial, with assessors blinded, and parallel group study with face-to-face components for assessment with a follow-up of 3 months. Patients with symptomatic PAD (Fontaine stage IIa or IIb) and possession of a mobile phone were eligible. Eligible participants were randomly assigned into study and control group, stratified by their distance covered in the 6-min walk test, using the software TENALEA. Participants randomized to the study group received usual care and the mobile intervention (trackPAD) for the follow-up period of 3 months, whereas participants randomized to the control group received only usual care. TrackPAD records the frequency and duration of training sessions and pain level using manual user input. Clinical outcome data were collected at the baseline and after 3 months via validated tools (6-min walk test, ankle-brachial index, and duplex ultrasound at the lower arteries) and self-reported quality of life. Usability and quality of the app was determined using the user version of the Mobile Application Rating Scale.
Results: The study enrolled 45 participants with symptomatic PAD (44% male). Of these participants, 21 (47%) were randomized to the study group and 24 (53%) were randomized to the control group. The distance walked in the 6-min walk test was comparable in both groups at baseline (study group: mean 368.1m [SD 77.6] vs control group: mean 394.6m [SD 100.6]).
Conclusions: This is the first trial to test a mobile intervention called trackPAD that was designed especially for patients with PAD. Its results will provide important insights in terms of feasibility, effectiveness, and patient preferences of an app-based mobile intervention supporting SET for the conservative treatment of PAD.
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.
Background: Mobile health interventions are intended to support complex health care needs in chronic diseases digitally, but they are mainly targeted at general health improvement and neglect disease-specific requirements. Therefore, we designed TrackPAD, a smartphone app to support supervised exercise training in patients with peripheral arterial disease.
Objective: This pilot study aimed to evaluate changes in the 6-minute walking distance (meters) as a primary outcome measure. The secondary outcome measures included changes in physical activity and assessing the patients’ peripheral arterial disease–related quality of life.
Methods: This was a pilot two-arm, single-blinded, randomized controlled trial. Patients with symptomatic PAD (Fontaine stage IIa/b) and access to smartphones were eligible. Eligible participants were randomly assigned to the study, with the control group stratified by the distance covered in the 6-minute walking test using the TENALEA software. Participants randomized to the intervention group received usual care and the mobile intervention (TrackPAD) for the follow-up period of 3 months, whereas participants randomized to the control group received routine care only. TrackPAD records the frequency and duration of training sessions and pain levels using manual user input. Clinical outcome data were collected at the baseline and after 3 months via validated tools (the 6-minute walk test and self-reported quality of life). The usability and quality of the app were determined using the Mobile Application Rating Scale user version.
Results: The intervention group (n=19) increased their mean 6-minute walking distance (83 meters, SD 72.2), while the control group (n=20) decreased their mean distance after 3 months of follow-up (–38.8 meters, SD 53.7; P=.01). The peripheral arterial disease–related quality of life increased significantly in terms of “symptom perception” and “limitations in physical functioning.” Users’ feedback showed increased motivation and a changed attitude toward performing supervised exercise training.
Conclusions: Besides the rating providing a valuable support tool for the user group, the mobile intervention TrackPAD was linked to a change in prognosis-relevant outcome measures combined with enhanced coping with the disease. The influence of mobile interventions on long-term prognosis must be evaluated in the future.
Ethikorientiert entscheiden
(2021)
In this paper, we propose and simulate a new type of three-dimensional (3D) optical splitter based on multimode interference (MMI) for the wavelength of 1550 nm. The splitter was proposed on the square basis with the width of 20 x 20 µm2 using the IP-Dip polymer as a standard material for 3D laser lithography. We present the optical field distribution in the proposed MMI splitter and its integration possibility on optical fiber. The design is aimed to the possible fabrication process using the 3D laser lithography for forthcoming experiments.
The goal of this paper is to design a low-loss 1 x 32 Y-branch optical splitter for optical transmission systems, using two different design tools employing Beam Propagation Method. As a first step, a conventional 1 x 32 Y-branch splitter was designed and simulated in two-dimensional environment of OptiBPM photonic tool. The simulated optical properties feature high loss, high asymmetric splitting ratio and a large size of the designed structure, too. In the second step of this work we propose an optimization of the conventional splitter design leading to suppression of the asymmetric splitting ratio to one-third of its initial value and to the improvement of the losses by nearly 2 dB. In addition, 50% size reduction of the designed structure was also achieved. This length-optimized low-loss splitter was then modelled in a three-dimensional environment of RSoft photonic tool and the simulated results confirm the strong improvement of the optical properties.
In this paper, low-loss Y-branch splitters up to 128 splitting ratio are designed, simulated, and optimized by using 2D beam propagation method in OptiBPM tool by Optiwave. For an optical waveguide, a silica-on-silicon material platform is used. The splitters were designed as a planar structure for a telecommunication operating wavelength of 1.55 m. According to the minimum insertion loss and minimum non-uniformity, the optimum length for each Y-branch is determined. The influence of the pre-defined S-Bend waveguide shapes (Arc, Cosine, Sine) and of the waveguide core size reduction on the splitter performance has been also studied. The obtained simulation results of all designed splitters with different S-Bend shape waveguides together with the different waveguide core sizes are discussed and compared with each other.
Brainstorming ist ein Mythos
(2021)
Rückblicke zur 5. ogsaTAGUNG
(2021)
Gender und sexuelle Orientierung im Alter - authentisches Verhalten förderlich für die Gesundheit?
(2021)
In the regime of incentive-based autonomous demand response, time dependent prices are typically used to serve as signals from a system operator to consumers. However, this approach has been shown to be problematic from various perspectives. We clarify these shortcomings in a geometric way and thereby motivate the use of power signals instead of price signals. The main contribution of this paper consists of demonstrating in a standard setting that power tracking signals can control flexibilities more efficiently than real-time price signals. For comparison by simulation, German renewable energy production and German standard load profiles are used for daily production and demand profiles, respectively. As for flexibility, an energy storage system with realistic efficiencies is considered. Most critically, the new approach is able to induce consumptions on the demand side that real-time pricing is unable to induce. Moreover, the pricing approach is outperformed with regards to imbalance energy, peak consumption, storage variation, and storage losses without the need for additional communication or computation efforts. It is further shown that the advantages of the optimal power tracking approach compared to the pricing approach increase with the extent of the flexibility. The results indicate that autonomous flexibility control by optimal power tracking is able to integrate renewable energy production efficiently, has additional benefits, and the potential for enhancements. The latter include data uncertainties, systems of flexibilities, and economic implementation.
Besser entscheiden
(2021)
Unüberschaubar viele Vorschläge des systematischen Entscheidens führen bei bestimmten Rahmenbedingungen zum Erfolg. Die berufliche Praxis weicht aber zumeist stark davon ab, daher sind viele Methoden unbrauchbar. Wie kann man dennoch seine Fähigkeit zu Entscheiden verbessern? Man orientiert sich an grundlegenden Handlungsmaximen.
Was Kennzahlen aussagen
(2021)
Was ist als Ergebnis der Operation 1 : 2 als „korrekt“ anzuerkennen? In der Menge der natürlichen Zahlen N ist 0 korrekt, in der Menge der rationalen Zahlen Q ist 0,5 richtig. Was „wahr“ ist, hängt also von den Ermittlungs- und Berechnungsgrundlagen ab. Das übersehen viele Führungskräfte beim Umgang mit Kennzahlen genau so, wie die Bedeutung ihrer kommunikativen Kompetenzen.
Entscheidungen herbeiführen
(2021)
Ein Entscheidungsprozess wird zusammengehalten von aufeinander Bezug nehmenden Kommunikationen, deren Geltungsanspruch die Kommunikationspartner voraussetzen. Möchte man eine Entscheidung herbeiführen, ist eine fachinhaltliche Expertise keinesfalls ausreichend. Notwendig ist eine Einbindung in das Netzwerk kommunikativer Entscheidungen, dann damit werden die Resonanzen generiert, die sich im Netzwerk entfalten und so die zu tätigende Entscheidungen beeinflussen.
Organisationsdesign
(2021)
Organisationsdesign bezeichnet die zielorientierte, kontextsensitive Gestaltung der Rahmenbedingungen einer Organisation(seinheit). Im Fokus stehen das Ermöglichen und Begrenzen von Formen von (bereichsübergreifenden) Kommunikationen und Entscheidungen, ohne diese letztendlich zu determinieren. Deshalb soll es ausdrücklich der jeweiligen konkreten Entscheidung vorbehalten bleiben, wie sie sich auf vorherige Entscheidungen bezieht.
Form einer Entscheidung
(2021)
Eine gute Entscheidungsfähigkeit braucht mehr als eine tiefe fachinhaltliche Expertise. Nötig ist eine kommunikative Anschlussfähigkeit an die internen Netzwerke, die durch Kommunikationen zusammengehalten werden. Warum? Weil eine Entscheidungsfindung geprägt ist von habitualisierten Verhaltensweisen der Repräsentanten dieser Netzwerke.
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?
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.
Ausgehandeltes Verständnis
(2020)
Entscheidungen über die optimierte organisatorische Wertschöpfung werden oft von mehreren Personen getroffen. Möchte die entscheidungsorientierte BWL anwendungsorientiert sein, legt sie den Fokus auf das Gewebe von aufeinander verweisenden (entscheidungsfördernden) Kommunikationen zu legen und auf der Erkenntnisfigur des Beobachters aufzubauen.
In der betriebswirtschaftlichen Fachliteratur ist die erkenntnistheoretische Denkfigur des Beobachters bis auf wenige Ausnahmen weitgehend ausgeblendet. Das muss nicht sein. Beispielsweise kann aus einer Beobachterperspektive notiert werden: Unternehmen ereignen sich, indem Beobachter auf eine Art und Weise tätig werden, die sie als Organisation von Gütern und Dienstleistungen, als Deckung fremder Bedarfe und als Verzinsung des eingesetzten Kapitals verstehen, voneinander unterscheiden und wechselseitig aufeinander beziehen.
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.
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!
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“).
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.
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.
Die Realität ist keinesfalls einfach da. Sie wird vielmehr von den Beteiligten erst kommunikativ erzeugt. Einzeln und gemeinsam werden Beobachtungen und damit erzielte Ergebnisse, gedankliche Vorstellungen, argumentative Begründungen sowie grundlegende Annahmen und damit zusammenhängende Deutungen schriftlich und/oder mündlich kommuniziert und miteinander ausgetauscht.
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.
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.
Ordnung aus der Mitte
(2021)
Bridges between families
(2016)
Mobility choices - an instrument for precise automatized travel behavior detection & analysis
(2021)
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.
Recently the use of microRNAs (miRNAs) as biomarkers for a multitude of diseases has gained substantial significance for clinical as well as point-of-care diagnostics. Amongst other challenges, however, it holds the central requirement that the concentration of a given miRNA must be evaluated within the context of other factors in order to unambiguously diagnose one specific disease. In terms of the development of diagnostic methods and devices, this implies an inevitable demand for multiplexing in order to be able to gauge the abundance of several components of interest in a patient’s sample in parallel. In this study, we design and implement different multiplexed versions of our electrochemical microfluidic biosensor by dividing its channel into subsections, creating four novel chip designs for the amplification-free and simultaneous quantification of up to eight miRNAs on the CRISPR-Biosensor X (‘X’ highlighting the multiplexing aspect of the device). We then use a one-step model assay followed by amperometric readout in combination with a 2-minute-stop-flow-protocol to explore the fluidic and mechanical characteristics and limitations of the different versions of the device. The sensor showing the best performance, is subsequently used for the Cas13a-powered proof-of-concept measurement of two miRNAs (miRNA-19b and miRNA-20a) from the miRNA-17∼92 cluster, which is dysregulated in the blood of pediatric medulloblastoma patients. Quantification of the latter, alongside simultaneous negative control measurements are accomplished on the same device. We thereby confirm the applicability of our platform to the challenge of amplification-free, parallel detection of multiple nucleic acids.
In this work, we present a significant step toward in vivo ophthalmic optical coherence tomography and angiography on a photonic integrated chip. The diffraction gratings used in spectral-domain optical coherence tomography can be replaced by photonic integrated circuits comprising an arrayed waveguide grating. Two arrayed waveguide grating designs with 256 channels were tested, which enabled the first chip-based optical coherence tomography and angiography in vivo three-dimensional human retinal measurements. Design 1 supports a bandwidth of 22 nm, with which a sensitivity of up to 91 dB (830 µW) and an axial resolution of 10.7 µm was measured. Design 2 supports a bandwidth of 48 nm, with which a sensitivity of 90 dB (480 µW) and an axial resolution of 6.5 µm was measured. The silicon nitride-based integrated optical waveguides were fabricated with a fully CMOS-compatible process, which allows their monolithic co-integration on top of an optoelectronic silicon chip. As a benchmark for chip-based optical coherence tomography, tomograms generated by a commercially available clinical spectral-domain optical coherence tomography system were compared to those acquired with on-chip gratings. The similarities in the tomograms demonstrate the significant clinical potential for further integration of optical coherence tomography on a chip system.
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.
Issues with professional conduct and discrimination against Lesbian, Gay, Bisexual, Transgender (LGBT+) people in health and social care, continue to exist in most EU countries and worldwide.
The project IENE9 titled: “Developing a culturally competent and compassionate LGBT+ curriculum in health and social care education” aims to enable teacher/trainers of theory and practice to enhance their skills regarding LGBT+ issues and develop teaching tools to support the inclusion of LGBT+ issues within health and social care curricula. The newly culturally competent and compassionate LGBT+ curriculum will be delivered though a Massive Open Online Course (MOOC) which is aimed at health and social care workers, professionals and learners across Europe and worldwide.
We have identified educational policies and guidelines at institutions teaching in health and social care, taken into account for developing the learning/teaching resources. The MOOC will be an innovative training model based on the Papadopoulos (2014) model for “Culturally Competent Compassion”. The module provides a logical and easy to follow structure based on its four constructs 'Culturally Aware and Compassionate Learning', 'Culturally Knowledgeable and Compassionate Learning', 'Culturally Sensitive and Compassionate Learning', 'Culturally Competent and Compassionate Learning'.
Specific training may result in better knowledge and skills of the health and social care workforce, which helps to reduce inequalities and communication with LGBT+ people, as well as diminishing the feelings of stigma or discrimination experienced.
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.
An electrochemical study with three redox substances on a carbon based nanogap electrode array
(2020)
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.
We present a new concept of 3D polymer-based 1 × 4 beam splitter for wavelength splitting around 1550 nm. The beam splitter consists of IP-Dip polymer as a core and polydimethylsiloxane (PDMS) Sylgard 184 as a cladding. The splitter was designed and simulated with two different photonics tools and the results show high splitting ratio for single-mode and multi-mode operation with low losses. Based on the simulations, a 3D beam splitter was designed and realized using direct laser writing (DLW) process with adaptation to coupling to standard single-mode fiber. With respect to the technological limits, the multi-mode splitter having core of (4 × 4) μm 2 was designed and fabricated together with supporting stable mechanical construction. Splitting properties were investigated by intensity monitoring of splitter outputs using optical microscopy and near-field scanning optical microscopy. In the development phase, the optical performance of fabricated beam splitter was examined by splitting of short visible wavelengths using red light emitting diode. Finally, the splitting of 1550 nm laser light was studied in detail by near-field measurements and compared with the simulated results. The nearly single-mode operation was observed and the shape of propagating mode and mode field diameter was well recognized.
Design and optimization of 1x2N Y-branch optical splitters for telecommunication applications
(2020)
This paper presents the design and optimization of 1x2N Y-branch optical splitters for telecom applications. A waveguide channel profile, used in the splitter design, is based on a standard silica-on-silicon material platform. Except for the lengths of the used Y-branches, design parameters such as port pitch between the waveguides and simulation parameters for all splitters were considered fixed. For every Y-branch splitter, insertion loss, non-uniformity, and background crosstalk are calculated. According to the minimum insertion loss and minimum non-uniformity, the optimum length for each Y-branch is determined. Finally, the individual Y-branches are cascade joined to design various Y-branch optical splitters, from 1x2 to 1x64.
We have demonstrated micromachining of bulk 3C silicon carbide (3C- SiC) wafers by employing 1028nm wavelength femtosecond laser pulses of energy less than 10 nJ directly from a femtosecond laser oscillator, thus eliminating the need for an amplified system and increasing the micromachining speed by more than four orders of magnitude.
We have investigated the ablation behaviour of single crystal SrTiO3 <100> with focus on the influence of the pulse duration at a wavelength of 248 nm. The experiments were performed with KrF-excimer lasers with pulse durations of 34 ns and 500 fs, respectively. Femtosecond-ablation turns out to be more efficient by one order of magnitude and to eliminate the known problem of cracking of SrTiO3 during laser machining with longer pulses. In addition, the cavities ablated with femtosecond pulses display a smoother surface with no indication of melting and well-defined, sharp edges. These effects can be explained by the reduced thermal shock effect on the material by using ultrashort pulses.
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.
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.
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.
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.
Quasilineare Tauchankerspule
(2020)
Gas hydrates are usually synthesized by bringing together a pressurized gas and liquid or solid water. In both cases, the transport of gas or water to the hydrate growth site is hindered once an initial film of hydrate has grown at the water–gas interface. A seemingly forgotten gas-phase technique overcomes this problem by slowly depositing water vapor on a cold surface in the presence of the pressurized guest gas. Despite being used for the synthesis of low-formation-pressure hydrates, it has not yet been tested for hydrates of CO 2 and CH 4 . Moreover, the potential of the technique for the study of hydrate decomposition has not been recognized yet. We employ two advanced implementations of the condensation technique to form hydrates of CO 2 and CH 4 and demonstrate the applicability of the process for the study of hydrate decomposition and the phenomenon of self-preservation. Our results show that CO 2 and CH 4 hydrate samples deposited on graphite at 261–265 K are almost pure hydrates with an ice fraction of less than 8%. Rapid depressurization experiments with thin deposits (approx. 330 mm thickness) of CO 2 hydrate on an aluminum surface at 265 K yield identical dissociation curves when the deposition is done at identical pressure. However, hydrates deposited at 1 MPa almost completely withstand decomposition after rapid depressurization to 0.1 MPa, while samples deposited at 2 MPa decompose 7 times faster. Therefore, this synthesis technique is not only applicable for the study of hydrate decomposition but can also be used for the controlled deposition of a super-preserved hydrate.
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.
The spatial redistribution of Japanese direct investment in the United Kingdom between 1991 and 2010
(2013)
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.
Investigation of non-uniformly emitting optical fiber diffusers on the light distribution in tissue
(2020)
Shaolin Wu Fo Dao – die Synthese japanischer und chinesischer Kampfkunst-Lehre auf der Grundlage zen-buddhistischer Theorie und Praxis ist eine neu geschaffene Disziplin. In dieser Fusion verbinden sich wesentliche Elemente aus Budo und Shaolin (-Wudao), deren traditionellen Körper-Geist-Übungen von Kampftechnik (Bu/Wu) und Meditation (Zen/Chan) als originäre Weg- und Heilslehre (Do/Dao) seit jeher der Persönlichkeits- und spirituellen Entwicklung des Ausübenden dienten.
Hier nun, in der Überwindung alter Grenzen zwischen japanischer und chinesischer Kampfkunstsysteme („hart“ und „weich“), wurde hier nun erstmaligen ein zusammengewachsenes Kampfkunstsystem kreiert, um die beidseits positiven Wirkungen auf den Menschen zu bündeln und – und das ist das Besondere – sie in den Dienst buddhistischer (Butsu, jap.: Buddha / chin. Fo) Psychologie und Psychotherapie zu stellen.
Die Verbindung von Budo mit Shaolin als eigenständiges praktisches Lehrkonzept, allein schon eine „revolutionäre Innovation“, erfährt durch ihren Einsatz als spezielle Methode einer Heilkunst zusätzlich Pioniercharakter in der Behandlung von Leid. Gemeint sind sowohl Ansätze aus der Budopädagogik und speziellen Budotherapie zur Heilung, Linderung oder Prävention von physischen, psychosomatischen und psychischen Krisen, Störungen, Krankheiten, Behinderungen und Leiden, als auch im Sinne des philosophischen und wissenschaftlichen Buddhismus, „das Leid in der Welt zu mindern“, zum Wohle des Menschen, für sein Glück und Frieden zu arbeiten.
The Digital Factory Vorarlberg is the youngest Research Center of Vorarlberg University of Applied Sciences. In the lab of the research center a research and learning factory has been established for educating students and employees of industrial partners. Showcases and best practice scenarios for various topics of digitalization in the manufacturing industry are demonstrated. In addition, novel methods and technologies for digital production, cloud-based manufacturing, data analytics, IT- and OT-security or digital twins are being developed. The factory comprises only a minimum core of logistics and fabrication processes to guarantee manageability within an academic setup. As a product, fidget spinners are being fabricated. A webshop allows customers to individually design their products and directly place orders in the factory. A centralized SCADA-System is the core data hub for the factory. Various data analytic tools and methods and a novel database for IoT-applications are connected to the SCADA-System. As an alternative to on premise manufacturing, orders can be pushed into a cloud-based manufacturing platform, which has been developed at the Digital Factory. A broker system allows fabrication in distributed facilities and offers various optimization services. Concepts, such as outsourcing product configuration to customers or new types of engineering services in cloud-based manufacturing can be explored and demonstrated. In this paper, we present the basic concept of the Digital Factory Vorarlberg, as well as some of the newly developed topics.
Lead–magnesium niobate lead titanate (PMN-PT) has been proven as an excellent material for sensing and actuating applications. The fabrication of advanced ultra-small PMN-PT-based devices relies on the availability of sophisticated procedures for the micro-machining of PMN-PT thin films or bulk substrates. Approaches reported up to date include chemical etching, excimer laser ablation, and ion milling. To ensure an excellent device performance, a key mandatory feature for a micro-machining process is to preserve as far as possible the crystalline quality of the substrates; in other words, the fabrication method must induce a low density of cracks and other kind of defects. In this work, we demonstrate a relatively fast procedure for the fabrication of high-quality PMN-PT micro-machined actuators employing green femtosecond laser pulses. The fabricated devices feature the absence of extended cracks and well-defined edges with relatively low roughness, which is advantageous for the further integration of nanomaterials onto the piezoelectric actuators.