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A device includes an input to sequential data associated to a face; a predictor configured to predict facial parameters; and a corrector configured to correct the predicted facial parameters on the basis of input data, the input data containing geometric measurements and other information. A related method and a related computer program are also disclosed.
BACKGROUND
Given the unreliable self-report in patients with dementia, pain assessment should also rely on the observation of pain behaviors, such as facial expressions. Ideal observers should be well trained and should observe the patient continuously in order to pick up any pain-indicative behavior; which are requisitions beyond realistic possibilities of pain care. Therefore, the need for video-based pain detection systems has been repeatedly voiced. Such systems would allow for constant monitoring of pain behaviors and thereby allow for a timely adjustment of pain management in these fragile patients, who are often undertreated for pain.
METHODS
In this road map paper we describe an interdisciplinary approach to develop such a video-based pain detection system. The development starts with the selection of appropriate video material of people in pain as well as the development of technical methods to capture their faces. Furthermore, single facial motions are automatically extracted according to an international coding system. Computer algorithms are trained to detect the combination and timing of those motions, which are pain-indicative.
RESULTS/CONCLUSION
We hope to encourage colleagues to join forces and to inform end-users about an imminent solution of a pressing pain-care problem. For the near future, implementation of such systems can be foreseen to monitor immobile patients in intensive and postoperative care situations.
Recently, we discovered a cholinergic mechanism that inhibits the adenosine triphosphate (ATP)-dependent release of interleukin-1 beta (IL-1 beta) by human monocytes via nicotinic acetylcholine receptors (nAChRs) composed of alpha 7, alpha 9 and/or alpha 10 subunits. Furthermore, we identified phosphocholine (PC) and dipalmitoylphosphatidylcholine (DPPC) as novel nicotinic agonists that elicit metabotropic activity at monocytic nAChR. Interestingly, PC does not provoke ion channel responses at conventional nAChRs composed of subunits alpha 9 and alpha 10. The purpose of this study is to determine the composition of nAChRs necessary for nicotinic signaling in monocytic cells and to test the hypothesis that common metabolites of phosphatidylcholines, lysophosphatidylcholine (LPC) and glycerophosphocholine (G-PC), function as nAChR agonists. In peripheral blood mononuclear cells from nAChR gene-deficient mice, we demonstrated that inhibition of ATP-dependent release of IL-1 beta by acetylcholine (ACh), nicotine and PC depends on subunits alpha 7, alpha 9 and alpha 10. Using a panel of nAChR antagonists and siRNA technology, we confirmed the involvement of these subunits in the control of IL-1 beta release in the human monocytic cell line U937. Furthermore, we showed that LPC (C16:0) and G-PC efficiently inhibit ATP-dependent release of IL-1 beta. Of note, the inhibitory effects mediated by LPC and G-PC depend on nAChR subunits alpha 9 and alpha 10, but only to a small degree on alpha 7. In Xenopus laevis oocytes heterologously expressing different combinations of human alpha 7, alpha 9 or alpha 10 subunits, ACh induced canonical ion channel activity, whereas LPC, G-PC and PC did not. In conclusion, we demonstrate that canonical nicotinic agonists and PC elicit metabotropic nAChR activity in monocytes via interaction of nAChR subunits alpha 7, alpha 9 and alpha 10. For the metabotropic signaling of LPC and G-PC, nAChR subunits alpha 9 and alpha 10 are needed, whereas alpha 7 is virtually dispensable. Furthermore, molecules bearing a PC group in general seem to regulate immune functions without perturbing canonical ion channel functions of nAChR.
Hydrogen sulfide stimulates CFTR in Xenopus oocytes by activation of the cAMP/PKA signalling axis
(2017)
Hydrogen sulfide (H2S) has been recognized as a signalling molecule which affects the activity of ion channels and transporters in epithelial cells. The cystic fibrosis transmembrane conductance regulator (CFTR) is an epithelial anion channel and a key regulator of electrolyte and fluid homeostasis. In this study, we investigated the regulation of CFTR by H2S. Human CFTR was heterologously expressed in Xenopus oocytes and its activity was electrophysiologically measured by microelectrode recordings. The H2S-forming sulphur salt Na2S as well as the slow-releasing H2S-liberating compound GYY4137 increased transmembrane currents of CFTR-expressing oocytes. Na2S had no effect on native, noninjected oocytes. The effect of Na2S was blocked by the CFTR inhibitor CFTR_inh172, the adenylyl cyclase inhibitor MDL 12330A, and the protein kinase A antagonist cAMPS-Rp. Na2S potentiated CFTR stimulation by forskolin, but not that by IBMX. Na2S enhanced CFTR stimulation by membranepermeable 8Br-cAMP under inhibition of adenylyl cyclase-mediated cAMP production by MDL 12330A. These data indicate that H2S activates CFTR in Xenopus oocytes by inhibiting phosphodiesterase activity and subsequent stimulation of CFTR by cAMP-dependent protein kinase A. In epithelia, an increased CFTR activity may correspond to a pro-secretory response to H2S which may be endogenously produced by the epithelium or H2S-generating microflora.
An increased bronchoconstrictor response is a hallmark in the progression of obstructive airway diseases. Acetylcholine and 5-hydroxytryptamine (5-HT, serotonin) are the major bronchoconstrictors. There is evidence that both cholinergic and serotonergic signaling in airway smooth muscle (ASM) involve caveolae. We hypothesized that caveolin-1 (cav-1), a structural protein of caveolae, plays an important regulatory role in ASM contraction. We analyzed airway contraction in different tracheal segments and extra-and intrapulmonary bronchi in cav-1 deficient (cav-1-/-) and wild-type mice using organ bath recordings and videomorphometry of methyl-beta-cyclodextrin (MCD) treated and non-treated precision-cut lung slices (PCLS). The presence of caveolae was investigated by electron microscopy. Receptor subtypes driving 5-HT-responses were studied by RT-PCR and videomorphometry after pharmacological inhibition with ketanserin. Cav-1 was present in tracheal epithelium and ASM. Muscarine induced a dose dependent contraction in all airway segments. A significantly higher Emax was observed in the caudal trachea. Although, caveolae abundancy was largely reduced in cav-1-/- mice, muscarine-induced airway contraction was maintained, albeit at diminished potency in the middle trachea, in the caudal trachea and in the bronchus without changes in the maximum efficacy. MCD-treatment of PLCS from cav-1-/- mice reduced cholinergic constriction by about 50%, indicating that cholesterol-rich plasma domains account for a substantial portion of the muscarine-induced bronchoconstriction. Notably, cav-1-deficiency fully abrogated 5-HT-induced contraction of extrapulmonary airways. In contrast, 5-HT-induced bronchoconstriction was fully maintained in cav-1-deficient intrapulmonary bronchi, but desensitization upon repetitive stimulation was enhanced. RT-PCR analysis revealed 5-HT1B, 5-HT2A, 5-HT6, and 5-HT7 receptors as the most prevalent subtypes in the airways. The 5-HT-induced-constriction in PCLS could be antagonized by ketanserin, a 5-HT2A receptor inhibitor. In conclusion, the role of cav-1, caveolae, and cholesterol-rich plasma domains in regulation of airway tone are highly agonist-specific and dependent on airway level. Cav-1 is indispensable for serotonergic contraction of extrapulmonary airways and modulates cholinergic constriction of the trachea and main bronchus. Thus, cav-1/caveolae shall be considered in settings such as bronchial hyperreactivity in common airway diseases and might provide an opportunity for modulation of the constrictor response.
What are the processes behind efforts for more sustainable mountain destinations in the German Alps and what are the views of different tourism stakeholders on these processes? The research deals both with threats pushing the agenda of sustainable development (such as climate change and depletion of resources), indicators of sustainable tourism (to measure the scope of change), as well as cross-border cooperation and stakeholder engagement in the German Alps. The data was collected through 30 interviews with individuals dealing with tourism development and sustainable tourism development in the German Alps. The findings suggest that a holistic approach and collection and dissemination of data and knowledge on sustainability are the basis for developing sustainable mountain tourism. Implementation and monitoring should focus on specific flagship sustainable tourism products, as well as on a destination in a broader sense and the sustainable tourism market. Three themes emerged as important for implementation of sustainable tourism in the German Alps: indicators of sustainable tourism, cross-border cooperation and stakeholder engagement.
In order to achieve the highest possible performance, the ray traversal and intersection routines at the core of every high-performance ray tracer are usually hand-coded, heavily optimized, and implemented separately for each hardware platform—even though they share most of their algorithmic core. The results are implementations that heavily mix algorithmic aspects with hardware and implementation details, making the code non-portable and difficult to change and maintain.
In this paper, we present a new approach that offers the ability to define in a functional language a set of conceptual, high-level language abstractions that are optimized away by a special compiler in order to maximize performance. Using this abstraction mechanism we separate a generic ray traversal and intersection algorithm from its low-level aspects that are specific to the target hardware. We demonstrate that our code is not only significantly more flexible, simpler to write, and more concise but also that the compiled results perform as well as state-of-the-art implementations on any of the tested CPU and GPU platforms.
This article analyzes how humanitarian and/or development organizations acting as intermediaries between scientists and vulnerable populations aim to make environmental changes visible while trying to meet local needs and demands for sustainable livelihoods. Based on an in-depth organizational case study in Southern Thailand, the research analyses the use of visualization tools to foster environmental knowledge and literacy while supporting both policymaking as well as citizen engagement. Drawing on insights from sociology of organizations, the study discusses the organizational reasons for the use of visualization tools, outlining the underlying coercive, mimetic and normative pressures that facilitate their proliferation in the context of environmental communication. The results show that both the participatory approach as well as the use of audiovisual and digital tools to communicate project goals and results have become indispensable and institutionalized tools in the organizational field of humanitarian and development aid. In this context, organizations have become intermediaries and translators between ‘climate risk’ scientists and ‘at risk’ people, thus, facilitating environmental communication. The results show that questions of trust and ownership of ideas play an important role in the context of livelihood related projects linked to climate change adaptation. In this context, not only does the style and content of communication, but also the relationship between the parties who communicate, have an impact upon the success or failure of managing options in climate change adaptation.
Damit IT-gestützte Produkte und Systeme vor unbefugter oder missbräuchlicher Nutzung wirksam geschützt sind, müssen sie mit Sicherheitsfunktionen ausgestattet sein, die benutzerfreundlich sind. Hierfür sind seitens der Entwickler sowohl Security- als auch Usability-Kenntnisse erforderlich. Da insbesondere Entwickler in kleinen und mittleren Unternehmen (KMU) oft nicht über tiefer gehende Kenntnisse in beiden Bereichen verfügen, bedürfen sie einer Unterstützung, z. B. in Form geeigneter Methoden und Werkzeuge. In diesem Beitrag werden ein Lösungsweg und eine Werkzeugsammlung vorgestellt, die Entwicklern in KMU dabei helfen, auf systematische Weise digitale Produkte und Systeme mit dem Qualitätsmerkmal Usable Security herzustellen.
Usable Security – Benutzerfreundliche Sicherheitsfunktionen für Software und interaktive Produkte
(2017)
Sowohl im geschäftlichen wie im privaten Umfeld müssen Software, Apps und vernetzte Technikprodukte mit Sicherheitsfunktionen ausgestattet sein, die auch für Laien und Gelegenheitsnutzer verständlich und benutzbar sind. Im Umgang mit sensiblen Daten können sich diese Produkte ansonsten schnell als Risiko entpuppen, etwa wenn Sicherheitsmechanismen aufgrund mangelnder Usability von den Nutzern falsch oder überhaupt nicht bedient werden. Der Begriff „Usable Security“ bezeichnet ein Qualitätsmerkmal bzw. einen Entwicklungsansatz für Sicherheitskomponenten von Software und technischen Produkten, in dessen Zentrum der Benutzer steht. Dieser Beitrag soll als Einführung in das Thema Usable Security dienen und zugleich für die Probleme bei der Entwicklung gebrauchstauglicher Sicherheitsfunktionen sensibilisieren. Er ist Teil einer Serie von insgesamt drei Artikeln. Die folgenden zwei Beiträge vertiefen spezifische Themen im Kontext der Entwicklung von Sicherheitsfunktionen auf Grundlage von Muster lösungen (Patterns) und der Ausgestaltung von Warnhinweisen.
Computer-Sicherheitswarnungen – Benutzerzentrierte Entwurfsansätze der Usable Security-Forschung
(2017)
Der dritte und letzte Teil der Artikel-Serie in dieser Ausgabe zum Thema Usable Security zeigt exemplarisch, wie Softwareentwickler mit den im Rahmen des USecureD-Projekts entwickelten Werkzeugen arbeiten können. Der Beitrag konzentriert sich dabei auf Prinzipien, Richtlinien und Patterns, die bei der Ausgestaltung gebrauchstauglicher Computer-Sicherheitswarnungen berücksichtigt werden sollten. Anhand dieser sehr ubiquitären Bestandteile eines jeden digitalen Produkts kann anschaulich gezeigt werden, wie aktuelle wissenschaftliche Erkenntnisse auf dem Gebiet der Usable Security praxisnah für Softwarearchitekturen und Programmierer verfügbar und anwendbar gemacht werden können.
Wie im Artikel „Usable Security – benutzerfreundliche Sicherheitsfunktionen für Software und interaktive Produkte“ in diesem Heft bereits herausgestellt wurde, gibt es einen hohen bedarf an gebrauchstauglichen sicherheitskomponenten in der softwarebranche.1 Dies bedeutet für softwarearchitekten und Programmierer, dass sie das neue Qualitätsmerkmal Usable Security vermehrt berücksichtigen und umsetzen müssen. seit Mai 2015 werden daher im Rahmen des Projekts usecureD („usable security by Design“, siehe Kasten in schmitt et. al (2016)) Methoden und Werkzeuge für softwareentwickler entworfen und umgesetzt, die bei der entwicklung von digitalen Artefakten mit dem Qualitätsmerkmal Usable Security unterstützen.
Forschen, forschen und nochmal forschen: Genau das haben sich Hartmut Schmitt, Peter Nehren, Luigi Lo Iacono und Peter Leo Gorski in diesem shortcut zur Aufgabe gemacht. In fünf Kapiteln stellen sie die Ergebnisse des Forschungsprojekts "USecureD - Usable Security by Design" vor und unterstützen damit Softwareentwickler bei der systematischen Entwicklung von Produkten mit dem Qualititäsmerkmal "Usable Security". Forschen Sie selbst ein wenig mit und lernen Sie alles zu spannenden Anwendungsmöglichketen, Werkzeugen, Testplattformen und Entscheidungshilfen.
Usable security puts the users into the center of cyber security developments. Software developers are a very specific user group in this respect, since their points of contact with security are application programming interfaces (APIs). In contrast to APIs providing functionalities of other domains than security, security APIs are not approachable by habitual means. Learning by doing exploration exercises is not well supported. Reasons for this range from missing documentation, tutorials and examples to lacking tools and impenetrable APIs, that makes this complex matter accessible. In this paper we study what abstraction level of security APIs is more suitable to meet common developers’ needs and expectations. For this purpose, we firstly define the term security API. Following this definition, we introduce a classification of security APIs according to their abstraction level. We then adopted this classification in two studies. In one we gathered the current coverage of the distinct classes by the standard set of security functionality provided by popular software development kits. The other study has been an online questionnaire in which we asked 55 software developers about their experiences and opinion in respect of integrating security mechanisms into their coding projects. Our findings emphasize that the right abstraction level of a security API is one important aspect to consider in usable security API design that has not been addressed much so far.
3D Printers as Sociable Technologies: Taking Appropriation Infrastructures to the Internet of Things
(2017)
The aim of this thesis is to investigate and optimize the camera system which is used for Filtered Rayleigh Scattering (FRS) measurement systems. Theoretical considerations about the integration of interference filters explain state-of-the-art accuracy limitations. Based on that promising modifications of the established FRS system are presented: test results indicate that frequency fringes - artifacts distorting FRS scans - are minimized by positioning the spectral bandpass filter between camera and first lens. As a tradeoff, the signal level decreases by 70 % to 75% depending on the beam path through the molecular filter. Furthermore, reference measurements without a bandpass filter account for a non-negligible iodine fluorescence background of about 1% of typical signal levels. All things considered following these results FRS systems can now be systematically optimized towards specific measurement tasks.
Maßgefertigte Abläufe
(2017)
Time of flight camera system
(2017)
Time of flight camera system
(2017)
Lichtlaufzeitkamerasystem
(2017)
Abstandsmeßsystem
(2017)