Refine
Departments, institutes and facilities
- Fachbereich Informatik (74)
- Fachbereich Wirtschaftswissenschaften (67)
- Institut für Technik, Ressourcenschonung und Energieeffizienz (TREE) (49)
- Fachbereich Angewandte Naturwissenschaften (47)
- Fachbereich Ingenieurwissenschaften und Kommunikation (31)
- Institut für Cyber Security & Privacy (ICSP) (30)
- Institute of Visual Computing (IVC) (20)
- Fachbereich Sozialpolitik und Soziale Sicherung (18)
- Institut für funktionale Gen-Analytik (IFGA) (18)
- Institut für Verbraucherinformatik (IVI) (10)
Document Type
- Conference Object (112)
- Article (92)
- Part of a Book (30)
- Book (monograph, edited volume) (23)
- Patent (11)
- Contribution to a Periodical (9)
- Doctoral Thesis (6)
- Bachelor Thesis (5)
- Report (5)
- Preprint (4)
Year of publication
- 2017 (310) (remove)
Has Fulltext
- no (310) (remove)
Keywords
- Controlling (3)
- Lehrbuch (3)
- stem cells (3)
- Aerodynamics (2)
- Analytical pyrolysis (2)
- Approximated Jacobian (2)
- Biomineralization (2)
- Computer Graphics (2)
- Concurrent Kleene Algebra (2)
- Cooperative Awareness Message (2)
This study deals with the in-situ detection of volume fractions of melt in labradorite and basalt at 0.3 GPa pressure and temperatures ranging from 400–1500 °C. Methods used were frequency dependent electrical conductivity (EC) and energy dispersive X-ray diffraction (EDX). These techniques allowed melt fraction determination under in-situ pressure and temperature conditions, while optical analysis (SEM) was performed on quenched samples. EC allowed detecting melt frac- tions as low as 0.03 due to changes in dielectric properties. Increasing melt fractions caused the formerly isolated melt bubbles to interconnect along grain boundaries, thus increasing the bulk conductivity. Electrical conductivity thus provides a measure for both, the formation of melt (dielectric property) and the degree of interconnection of melt (bulk conductivity). Energy dispersive X-ray diffraction experiments (EDX) provided an additional measure for the volume fraction of melt. EDX diffraction data were used to calculate the volume fraction of melt on the basis of the peak to background ratio. In a final step the experimental data (SEM, EC, EDX) were compared with geometric models of melt distribution, namely the Archie-, cube-, tube-, Hashin-Shtrikman HS + and HS - model. The electrical "polarisability" data closely fit the HS + model, while bulk conductivity data were found to be less sensitive for melt fraction detection.
Infection Exposure Promotes ETV6-RUNX1 Precursor B-cell Leukemia via Impaired H3K4 Demethylases
(2017)
ETV6-RUNX1 is associated with the most common subtype of childhood leukemia. As few ETV6-RUNX1 carriers develop precursor B cell acute lymphocytic leukemia (pB-ALL), the underlying genetic basis for development of full-blown leukemia remains to be identified, but the appearance of leukemia cases in time-space clusters keeps infection as a potential causal factor. Here we present in vivo genetic evidence mechanistically connecting preleukemic ETV6-RUNX1 expression in hematopoetic stem cells/peripheral cells (HSC/PC) and postnatal infections for human-like pB-ALL. In our model, ETV6-RUNX1 conferred a low risk of developing pB-ALL after exposure to common pathogens, corroborating the low incidence observed in humans. Murine preleukemic ETV6-RUNX1 pro/preB cells showed high Rag1/2 expression, known for human ETV6-RUNX1 pB-ALL. Murine and human ETV6-RUNX1 pB-ALL revealed recurrent genomic alterations, with a relevant proportion affecting genes of the lysine demethylase (KDM) family. KDM5C loss-of-function resulted in increased levels of H3K4me3, which co-precipitated with RAG2 in a human cell line model, laying the molecular basis for recombination activity. We conclude that alterations of KDM family members represent a disease-driving mechanism and an explanation for RAG off-target cleavage observed in humans. Our results explain the genetic basis for clonal evolution of an ETV6-RUNX1 preleukemic clone to pB-ALL after infection exposure and offer the possibility of novel therapeutic approaches.
In today’s business, culture plays a vital role or to a high degree influences the attitude, perception and decision making process of an individual. Culture is an unavoidable state of rules and regulations that defines people’s daily life in a particular environment or society. There are plenty examples of business failures or stagnation or failure of joint ventures, on account of the management's inability to recognize cross-cultural challenges and tackle them appropriately.
Sie leiten ein heterogenes oder agiles Team und merken, dass Sie bisherige Führungsgrundsätze überdenken müssen? In diesem Spotlight erfahren Sie, wie Sie mit dem Wandel zur Agilität und mit Diversity in Ihrem Team umgehen können. Sie erhalten Unterstützung beim Thema Delegieren oder wenn Sie sich mit widersprüchlichen Führungszielen konfrontiert sehen. Außerdem zeigen Ihnen unsere Autoren mit direkt einsetzbaren Tipps, wie Sie wertschätzend führen sowie für Verbindlichkeit und ein gemeinsames Verständnis im Projektteam sorgen.
OpenDaylight (ODL) is a commercial, collaborative, open-source platform to accelerate the adoption and innovation of Software Defined Networking (SDN) and Network Function Visualization. This paper describes the novel ODL architecture in a simplified way to grasp a better understanding of such architecture. ODL architecture intends to foster new innovation and accelerate adoption of programming the network. The innovation of Model-Driven Service Abstraction Layer (MD-SAL) in the architecture leads to developing models for automatic management and configuration of the networks. MD-SAL provides ODL with the ability to support any protocol talking to the network elements as well as any network application. The flexibility inherent in ODL architecture could enable ODL to shape the next generation networks.
This study sought to determine the relationship between entrepreneurial education and youth employability and economic development in Kenya. A descriptive cross sectional design was used to collect data, with the main data collection instrument being a semi structured questionnaire. The population of the study comprised the micro, small and medium scale enterprises in Nairobi, Kenya. Out of the 100 questionnaires issued, 93 were completed and returned giving a response rate of 93%. Descriptive analysis (means and standard deviations ) and inferential analysis was used to analyze the data. Regression and correlation analysis was done to test the hypotheses. It was found that several indicators of entrepreneurial education had a significantly positive influence on youth employability. For example, entrepreneurial education enhances opportunity recognition as an indicator of entrepreneurial education was statistically significantly correlated with the statement that entrepreneurship endeavor is an employment alternative as an indicator of youth employability (r = 331**, P = 0.01). Similarly, the statement that entrepreneurial education sharpens competitiveness had a significantly positive influence on the statement that entrepreneurship endevour is an employment alternative (r =.313** P = 0.01). The overall model for entrepreneurial education and youth employability had an R Square value of 0.151, and an F value of 3.086, (p = 0.013 < 0.05), indicating that the influence is significant at the 0.05 level. The study found that most indicators of youth employability had a significantly positive correlation with indicators of economic development. It was found that there was a significant positive correlation between entrepreneurial education enhances new product and service development and entrepreneurial education reduces youth unemployment (r =0.304**, P = 0.01), while entrepreneurial education enhances new product and service development also has a positive correlation with entrepreneurial education reduces youth unemployment (.304** , P = 0.01). The overall model for youth employability and economic development had an R square value of .087 and F value of 2.103, p =0.87 > 0.05, indication that although youth employability is responsible for 8.7% of economic development, the effect is not statistically significant. The implication for this is that entrepreneurial education should be encouraged as a way of enhancing entrepreneurial thinking among the youth, so that they can use this to venture into self employment. However, this study did not find a significant direct link between youth employability and economic development, and this can only be implied. We suggest increased government support for entrepreneurship training and for closer industry university collaboration and partnerships in order to accelerate economic development.
Access to affordable energy - for basic needs as well as for national economic development - is a crucial concern for developing countries. Access to modern and sustainable energy services in rural areas, where the majority of the population is living in poverty, is a particularly urgent challenge, and one which has been recognized as crucial within the global development agenda.
The current dominant development model, focused on achieving macro-economic growth, gives priority to large-scale or centralized energy infrastructures for national growth or for meeting the urban demand. Rural areas of poorer countries are often at a disadvantage in terms of access to all types of services – roads, health facilities, markets, information and clean water. The high cost of providing these services in remote areas has led to new approaches being tried, based on self-help and the private sector rather than traditional government-led solutions. The missing access to electricity is primarily the reason for the poor operational environment of entrepreneurship especially in rural areas of developing countries, which poses many barriers to their development and limits their competitiveness. Energy services for household, agriculture and production serve as best examples as sectors exposed to enable entrepreneurship by productive use of renewable energy.
This paper describes the line-up, the challenges and the outcome of a development project in rural Ethiopia to support entrepreneurship based on the usage of renewable energy, in this case mainly photo-voltaic technology. In particular, this study tries to show up key features which are required to enable sustainable energy access and foster implementation challenges of developed business models in practice. Based on this experience, the paper discusses implications and lessons learned for a further development.
The non-farm sector is critical for the socio-economic development of Ghana especially the rural poor. Literature suggest that people engage in non-farm enterprises as a way out of poverty or a survival strategy, perhaps as a substitute for the landless. This paper analyses the determinants of individual participation in non-farm enterprises and the intensity of participation. The paper uses EGC/ISSER Socio-Economic Panel Survey data collected in 2009. The paper estimated the determinants of participation using a probit model and then estimated the intensity of participation using a truncated regression model. The results indicate that majority of women (about 73%) are engaged in non-farm enterprises in rural Ghana. The study found that females tended to participate more in non-farm self-employment and are less likely to participate in non-farm wage employment. The results further showed that individual characteristics such as the gender of the individual, being head of a household, being the spouse of a household head, having formal education, age of the individual, having access to credit, possessing a mobile phone, per capita landing holding and ownership of livestock influenced the participation of individuals in self-and wage employment. Results from truncated regression model for self-employed enterprises showed that having access to mobile phones, owning more livestock and electricity are important in determining the intensity of participation in self-employed enterprises. For wage-employment, being a household head, spouse of household head, having access to mobile phone and owning more livestock increased the number of days working on wage employment. Education is relevant for employment in the non-farm sector especially wage-employment. Government should play a lead role in making formal education accessible to the rural people. Deliberate policies should focus on addressing critical factors such as access to credit, mobile phone, electricity and education which are relevant for increasing participation intensity in rural enterprises.
Over the past decades, growing trends in social media, e-literacy and globalisation have led to the increased use of electrical and electronic equipment (EEE) in offices, schools, homes, hospitals and other institutions. Although, there are more efforts at introducing diversity, innovation and increased use of EEE, there had been limited effort at managing the end?of?life of these electronic devices. Evidence from previous research showed that the management of the end of life of electronic waste is highly dominated by Micro, Small and Medium Sized Enterprises (MSMEs) in the informal sector who employ more crude technology in their operations. This exploratory study therefore, sought to examine the activities of corporate bodies and MSMEs (formal and informal) in the e-waste sector in the Accra and Kumasi Metropolitan Areas in Ghana. Data was collected via questionnaires and interview from randomly selected respondents in the two metropolises. Results reveal that even though corporate institutions import a lot of electrical and electronic equipment, they do not have any policies on disposal of the e-waste generated. Thus, a high percentage of the e-waste generated is processed by the informal sector. The implications of the results are that policy makers and other stakeholders should encourage MSMEs to formalize their activities, support investment and green business development as well as funding and training for MSMEs operating in the sector.
Small and Medium Enterprises (SMEs) are engine of economy both for developed and developing countries. They play a significant role in income generation, job creation, poverty reduction and reducing income inequality. In Burundi, key stakeholders such as policy-makers as well as other international and national actors have made more effort to develop the segment of SMEs. Indeed, many start-ups have been created but are however, exposed to several challenges in their business operations. This paper aimed at investigating main critical barriers to SMEs growth and development in Burundi. The research was based upon a sample survey of small firms in Burundi and 314 small enterprises were surveyed. Rural start-ups’ critical barriers identified are mainly poor management, lack of access to market flow, lack of working capital, inadequate qualified workforce and low selling prices. On the other hand, five severe obstacles for urban SMEs identified are insecurity, access to financing, macroeconomic situation, lack of customers and unfair competition. A better understanding of all these barriers that SMEs are facing is useful to set up best strategies susceptible to increase their growth.
Entrepreneurship education serves a conduit for new venture creation as it provides the knowledge and skills needed to increase the self-efficacy of individuals to start and run new businesses and to grow existing ones. This study, therefore, sought to assess the relationship between the approaches to the teaching of entrepreneur-ship and entrepreneurial intention on a cohort of 292 respondents consisting of students who have studied entrepreneurship in three selected Universities. A structured questionnaire was used to obtain data randomly from students. The canonical correlation results indicate that education for and through entrepreneurship is the best approach to promoting entrepreneurial intensity among University students, if the aim of teaching entrepreneur-ship is to promote start-up activities. The findings provide valuable insights for institutions of higher learning and policy makers in Ghana with respect to the appropriate methodologies to be adopted in the teaching of entrepreneurship in our universities.
Media development cooperation has aimed for decades at enhancing free and independent media in developing countries as well as economies in transition. Within this field of activity, the concept of media viability has gained more and more attention in recent years. This is mainly due to a proposal of UNESCO`s intergovernmental Bureau of the International Programme for the Development of Communication (IPDC). The UNESCO, in partnership with DW Akademie, has drafted a list of indicators that delineate the influencing factors of media viability for media organizations in any given country (UNESCO 2015).
As a consequence of the novelty of the media viability concept, the state of scientific research is restricted. It is frequently focused on isolated case studies without providing a scientific basis for comparison. Empirical studies and comparative analyses are limited to certain media sectors such as the print market, as well as for journalism startups and spin-offs in developed economies.
Ressourcenschutz im Fokus
(2017)
We present a new interface for interactive comparisons of more than two alternative documents in the context of a generative design system that uses generative data-flow networks defined via directed acyclic graphs. To better show differences between such networks, we emphasize added, deleted, (un)changed nodes and edges. We emphasize differences in the output as well as parameters using highlighting and enable post-hoc merging of the state of a parameter across a selected set of alternatives. To minimize visual clutter, we introduce new difference visualizations for selected nodes and alternatives using additive and subtractive encodings, which improve readability and keep visual clutter low. We analyzed similarities in networks from a set of alternative designs produced by architecture students and found that the number of similarities outweighs the differences, which motivates use of subtractive encoding. We ran a user study to evaluate the two main proposed difference visualization encodings and found that they are equally effective.
Biomass in general, wood and grasses in particular represent attractive renewable sources for the fabrication of so-called building block chemicals (1). Thus, environmentally benign antimicrobial nanoparticles based on a silver-infused lignin core were recently reported underlying the high potential for valorization of lignin (2). The contribution presents specific correlations regarding the structural differences of lignins depending on both: source (wood vs. grass) and isolation procedure (Kraft vs. Organosolv). Special focus will be drawn on detailed structure deviations caused by Miscanthus genotypes (M. gigantheus, M. robustus, M. sisnensis).
Die Buchreihe Sustainable Development in the 21st Century bietet eine hervorragende Plattform für neuere und innovative Forschungsbeiträge zu wichtigen Aspekten globaler nachhaltiger Entwicklung und Resilienz zu Zeiten rapiden globalen Wandels. Die Reihe beinhaltet ausgewählte Monografien, Sammelbände und Tagungsbände sowie exzellente Dissertationen, Habilitationen und ähnliche Qualifikationsarbeiten. Der herausgeberische Schwerpunkt der Reihe liegt auf der Frage, welche Akteure, Strukturen und Prozesse nachhaltige Entwicklung in der heutigen interdependenten, hochkomplexen Weltlage ermöglichen oder erschweren. Hierzu werden unterschiedliche disziplinäre und diskursive Sichtweisen herangezogen mit dem Ziel, grundlegende Aspekte und Dimensionen nachhaltiger Entwicklung (wie z.B. Politik, Governance und Institutionen, Risiko- und Resilienzforschung, sozial-ökologische Systeme, menschliche Sicherheit, soziales Lernen oder ethische Dimensionen) zu erörtern und auch im Zusammenhang darzustellen. Die Autoren der Buchreihe sind weltweit anerkannte und namhafte Experten sowie herausragende Nachwuchsautoren aus den Sozial- und Geisteswissenschaften, Ökonomie und Rechtslehre, aber auch Praxisvertreter aus Politik und Gesellschaft. Die Reihentitel erscheinen in deutscher oder englischer Sprache.
Die Glücksforschung befasst sich primär mit einzelnen Konstrukten wie Arbeitszufriedenheit oder subjektivem Wohlbefinden. Allerdings fehlt ein zusammenhängendes Konzept, um die Erkenntnisse in der Praxis umzusetzen. Daher wird ein Bedürfnismodell vorgestellt, das sich nach ersten empirischen Untersuchungen als geeigneter Indikator für Wohlbefinden erweist. Außerdem lassen sich daraus konkrete Handlungsempfehlungen ableiten.
The detection of human skin in images is a very desirable feature for applications such as biometric face recognition, which is becoming more frequently used for, e.g., automated border or access control. However, distinguishing real skin from other materials based on imagery captured in the visual spectrum alone and in spite of varying skin types and lighting conditions can be dicult and unreliable. Therefore, spoofing attacks with facial disguises or masks are still a serious problem for state of the art face recognition algorithms. This dissertation presents a novel approach for reliable skin detection based on spectral remission properties in the short-wave infrared (SWIR) spectrum and proposes a cross-modal method that enhances existing solutions for face verification to ensure the authenticity of a face even in the presence of partial disguises or masks. Furthermore, it presents a reference design and the necessary building blocks for an active multispectral camera system that implements this approach, as well as an in-depth evaluation. The system acquires four-band multispectral images within T = 50ms. Using a machine-learning-based classifier, it achieves unprecedented skin detection accuracy, even in the presence of skin-like materials used for spoofing attacks. Paired with a commercial face recognition software, the system successfully rejected all evaluated attempts to counterfeit a foreign face.
Medizintourismus
(2017)
Jährlich entscheiden sich Millionen Menschen für eine Behandlung in auslndischen Kliniken, da beispielsweise die medizinische Versorgung im Heimatland nicht gewährleistet oder mangelhaft ist, der Weg zum Spezialisten im Nachbarland kürzer ist als im eigenen Land oder die Behandlung im Ausland deutlich preiswerter ist als zu Hause. Rund 30 Länder sind weltweit im Segment Medizintourismus stark engagiert, weitere 70 Nationen verfügen über einzelne Kliniken mit einer Anziehungskraft für internationale Patienten.
Die demografische Entwicklung spielt für Immobilieninvestoren eine große Rolle. Schließlich entscheidet die zukünftige Anzahl der Nutzer über die Nachfrage. Im Büroimmobilienmarkt ist daher vor allem die Anzahl der Bürobeschäftigten relevant, die sich wiederum aus dem Erwerbspersonenpotenzial ableitet. Auf Basis der Untersuchungen des Instituts der deutschen Wirtschaft zur Bürobeschäftigung und zur demografischen Entwicklung lassen sich die demografischen Perspektiven für den Büromarkt bis zum Jahr 2035 ableiten. Deutschlandweit ist nach einem kurzfristigen Anstieg mit einer Stagnation der Büronachfrage zu rechnen. In den Großstädten wird dagegen die Nachfrage weiter steigen. Vor allem in München und Berlin legt die Nachfrage kräftig zu, je nach Szenario zwischen 12 und 18 Prozent. In Düsseldorf, Hamburg und Frankfurt am Main liegen die Zuwächse dagegen zwischen 6 und 9 Prozent bis 2035. Im Vergleich zum Wohnungsmarkt sind die demografischen Perspektiven für den Büromarkt jedoch insgesamt schlechter, da die Anzahl der Erwerbspersonen langsamer wächst als die Gesamtbevölkerung. Zudem müssen bei langfristigen Betrachtungen auch mögliche Verschiebungen der Nachfrage, etwa durch die Digitalisierung, beachtet werden. Gerade in Kombination mit dem zunehmenden Fachkräftemangel können heutige Büroarbeitsplätze durch Verlagerungen ins Ausland oder durch Automatisierung wegfallen.
Maßgefertigte Abläufe
(2017)
„Sind Sie Gärtner oder Maschinist?“ (Zechlin 2010) – wer diese Frage einem Hochschulmanager stellt, der transportiert damit gleich dreierlei: zum einen die Frage, was für ein Typ man ist. Im Fokus steht der Hochschulmanager, der gießt, pflegt, vielleicht einmal die Äste stutzt, oder, im Gegenteil, den Hebel umlegt und erwartet, dass die Produktion läuft. Zum anderen stellt sich die Frage, um welches Gebilde es sich da eigentlich handelt, dem der Gärtner zum Wachstum und der Maschinist zur Produktivität verhilft. Zum Dritten offenbart sich die Frage nach dem Oder, also nach den vielfältigen denkbaren Konstellationen der beiden Pole Gärtner oder Maschinist sowie Gebilden, die weder Garten noch Maschine sind und ganz anderer Steuerungsimpulse bedürfen. Um Hochschulleitungen und Hochschulen zu beschreiben, gibt es, darauf deutet die Metapher hin, zahlreiche Modelle und Typologien. Die Praxis des Steuerungshandelns offenbart jedoch im Detail zahllose individuelle Ausprägungen und situationsbedingte Spezifika. Immer wieder heißt es, mit Blick auf die vielen Unterschiede müsse die Haltbarkeit von Annahmen und Modellen über Hochschulsteuerung am konkreten Einzelfall geprüft werden. In der Führungspraxis an einer Hochschule, hier am Beispiel der Hochschule Bonn-Rhein-Sieg, wird ein solcher Einzelfall beschrieben. Die per Gesetz gestärkte Hochschulleitung nutzte ihren Gestaltungsspielraum, um Hochschulentwicklungsplanungsprozesse nach eigener Aussage partizipativ vorzunehmen. Die partizipativen Prozesse sollten es ermöglichen, die Leitungsaufgaben im Hinblick auf Profilbildung, Richtungsweisung, Zukunftsgestaltung und Ressourcenzuweisung adäquat erfüllen zu können.
Das Buch beschreibt den seit 2012 bereits eingeleiteten Agenda-2030-Konsultationsprozess, der insbesondere in Europa bis zum Jahr 2020 zu einer Umgestaltung von Wirtschaft und Gesellschaft führen wird. Erstmalig in der Geschichte kommt ab Mitte des Jahres 2016 ein globales Managementsystem zum Einsatz, das zur Fortschrittsüberwachung der 17 Sustainable Development Goals (SDGs) und den 169 globalen Unterzielen weltweit eingesetzt wird. Ein Screening der relevanten politischen Strategien und Beschlüsse verdeutlicht, dass Europa und Deutschland gut auf die Umsetzung der neuen Agenda vorbereitet sind und sich im Zuge der neuen Rechenschaftspflicht zur Umsetzung der SDGs verpflichtet haben. Traditionelle Footprint-Indikatoren, neue Ergänzungsindikatoren sowie standardisierte Richt- und Leitlinien kommen im vorstehenden Zusammenhang zukünftig zum Einsatz. Die zielorientierte globale Steuerung der SDGs fällt in das Aufgabenfeld der Koordinationsfunktion des Life-Cycle-Controllings, das beschrieben wird. Unternehmen tragen maßgeblich zur Umsetzung der SDGs bei und sind daher zunehmend verpflichtet, die negativen Auswirkungen ihres unternehmerischen Handelns transparent zu machen. Dies geschieht mithilfe von Product-Footprints und Footprints für Transportdienstleistungen, die bezüglich ihrer aktuellen und zukünftigen Praxisrelevanz ebenfalls vorgestellt werden. Zahlreiche Praxisbeispiele zeigen zudem, wie Unternehmen schon heute über den Einsatz von SDG- und CSR-Fortschrittsindikatoren ihrer globalen Sorgfaltspflicht in den Lieferantenketten nachkommen.
Auf der Suche nach einem CO2-Filtermaterial für niedrige Partialdrücke wurden Aerogel-Beads aus Chitosan analysiert. Da zahlreiche Publikationen und Reviews auf die Fähigkeit von Aminen CO2 zu adsorbieren hinweisen, wurden diese Beads funktionalisiert, um den Amingehalt im Netzwerk und damit die Adsorptionskapazität zu erhöhen. Die Beads wurden mit Hilfe eines JetCutters hergestellt, mit Polyethylenimin (PEI), p-Phenylendiamin (PPD) und 1,2-Epoxyhexan (EH) funktionalisiert und anschließend überkritisch getrocknet. Die Ansätze wurden bei jeweils unterschiedlichen pH-Werten durchgeführt, um Aussagen über den Einfluss von NaOH auf die Reaktion treffen zu können. Alle Proben wurden mit für Aerogele typischen Methoden charakterisiert und auf ihre CO2-Adsorptionskapazität untersucht. Die Adsorptionskapazität der Chitosan Beads konnte durch Aufpfropfen der oben genannten Stoffe nur leicht verbessert werden, während die Funktionalisierung mit PPD dagegen überraschender Weise negative Auswirkungen hatte. Eine Funktionalisierung findet auch in Abwesenheit von NaOH statt.
A deployment of the Vehicle-2-Vehicle communication technology according to ETSI is in preparation in Europe. Currently, a policy for a necessary Public Key Infrastructure to enrol cryptographic keys and certificates for vehicles and infrastructure component is in discussion to enable an interoperable Vehicle-2-Vehicle communication. Vehicle-2-Vehicle communication means that vehicles periodically send Cooperative Awareness Messages. These messages contain the current geographic position, driving direction, speed, acceleration, and the current time of a vehicle. To protect privacy (location privacy, “speed privacy”) of vehicles and drivers ETSI provides a specific pseudonym concept. We show that the Vehicle-2-Vehicle communication can be misused by an attacker to plot a trace of sequent Cooperative Awareness Messages and to link this trace to a specific vehicle. Such a trace is non-disputable due to the cryptographic signing of the messages. So, the periodically sending of Cooperative Awareness Messages causes privacy problems even if the pseudonym concept is applied.
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.
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.
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.
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.
In der vorliegenden Arbeit wird ein Verfahren zur Segmentierung von Außenszenen und Terrain-Klassifkation entwickelt. Dazu werden 360 Grad-Laserscanner-Aufnahmen von Straßen, Gebäudefassaden und Waldwegen aufgenommen. Von diesen Aufnahmen werden verschiedene visuelle Repräsentationen in 2D erstellt. Dazu werden die Distanzinformationen und Winkelübergänge der Polarkoordinaten, die Remissionswerte und der Normalenvektor eingesetzt. Die Berechnung des Normalenvektors wird über ein modernes Verfahren mit einerniedrigen Laufzeit durchgeführt. Anschließend werden Oberflächeneigenschaften innerhalb einer Punktwolke analysiert und vier Klassen unterschieden: Untergrund, Vegetation, Hindernis und Himmel. Die Segmentierung und Klassifkation geschieht in einem Schritt. Dazuwird die Varianz auf den N ormalen über eine Filtermaske berechnet und ein Deskriptor erstellt. Der Deskriptor beinhaltet die Normalenvektoren und die Normalenvarianz fürdie x-, y- und z-Achse. Die Ergebnisse werden als Überblendung auf dem Remissionsbilddargestellt. Die Auswertung wird über eigens erstellte Ground-Truth-Daten vorgenommen. Dazu wird das Remissionsbild genutzt und der Ground-Truth mit verschiedenen Farben eingezeichnet. Die Klassifkationsergebnisse sind in Precision-Recall-Diagrammen dargestellt.