Refine
Departments, institutes and facilities
- Fachbereich Wirtschaftswissenschaften (28)
- Fachbereich Angewandte Naturwissenschaften (27)
- Institut für funktionale Gen-Analytik (IFGA) (20)
- Fachbereich Informatik (16)
- Fachbereich Sozialpolitik und Soziale Sicherung (11)
- Institut für Technik, Ressourcenschonung und Energieeffizienz (TREE) (10)
- Fachbereich Ingenieurwissenschaften und Kommunikation (8)
- Institut für Verbraucherinformatik (IVI) (6)
- Institut für Cyber Security & Privacy (ICSP) (5)
- Institute of Visual Computing (IVC) (5)
Document Type
- Article (105) (remove)
Year of publication
- 2017 (105) (remove)
Keywords
- Enzyme activity (2)
- Fatty acid metabolism (2)
- sustainability (2)
- 3D Printer (1)
- 3D user interfaces (1)
- 5-HT (1)
- ABT-737 (1)
- ALPS (1)
- AMT (1)
- Adipogenic effect (1)
3D Printers as Sociable Technologies: Taking Appropriation Infrastructures to the Internet of Things
(2017)
This work presents the analysis of data recorded by an eye tracking device in the course of evaluating a foveated rendering approach for head-mounted displays (HMDs). Foveated rendering methods adapt the image synthesis process to the user’s gaze and exploiting the human visual system’s limitations to increase rendering performance. Especially, foveated rendering has great potential when certain requirements have to be fulfilled, like low-latency rendering to cope with high display refresh rates. This is crucial for virtual reality (VR), as a high level of immersion, which can only be achieved with high rendering performance and also helps to reduce nausea, is an important factor in this field. We put things in context by first providing basic information about our rendering system, followed by a description of the user study and the collected data. This data stems from fixation tasks that subjects had to perform while being shown fly-through sequences of virtual scenes on an HMD. These fixation tasks consisted of a combination of various scenes and fixation modes. Besides static fixation targets, moving tar- gets on randomized paths as well as a free focus mode were tested. Using this data, we estimate the precision of the utilized eye tracker and analyze the participants’ accuracy in focusing the displayed fixation targets. Here, we also take a look at eccentricity-dependent quality ratings. Comparing this information with the users’ quality ratings given for the displayed sequences then reveals an interesting connection between fixation modes, fixation accuracy and quality ratings.
Das autonome Fahren wird die Mobilität revolutionieren. Um die Auswirkung der Vollautomation auf dieEigenschaften der Verkehrsmittel und die Präferenzen der Nutzer besser zu verstehen, haben wir dieNutzenwerte neuen Verkehrsmodi im Vergleich zu den bestehenden Verkehrsmodi analysiert und imRahmen einer Online-Umfrage von potentiellen Nutzern in Form eines vollständigen Paarvergleichsbewerten lassen. Die Studie zeigt, dass der Privat-PKW, unabhängig davon ob traditionell odervollautomatisiert, zwar nach wie vor das präferierte Verkehrsmittel ist, im direkten Vergleich das Carsharingjedoch viel stärker von der Vollautomation profitiert. Darüber hinaus gibt es Hinweise darauf, dass dasvollautomatisierte Carsharing verstärkt in Konkurrenz zum ÖPNV tritt.
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.
Enterprises demand universities not to limit education to theoretical knowledge, but instead, to prepare students for future challenges in the job. While demanding a focus on current technologies and practices appears reasonable, it contradicts academia’s general focus on sustainable knowledge. This “conflict-ofinterest” can be bridged through extra-curricular professional training. MOOCs are hyped as solution because they allow to simultaneously addressing masses of students. However, with the increasing number of learners, anonymity in education increases and first-level support decreases. Within the extracurricular online program erp4students we found that individual support is considered most relevant to successfully complete professional training.
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.
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.
Multiple myeloma is the second most common hematological malignancy. Despite all the progress made in treating multiple myeloma, it still remains an incurable disease. Patients are left with a median survival of 4-5 years. The combined treatment of multiple myeloma with histone deacetylase inhibitors and cytokine-induced killer cells provides a promising targeted treatment option for patients. This study investigated the impact of a combined treatment compared to treatment with histone deacetylase inhibitors. The experiments revealed that a treatment with histone deacetylase (HDAC) inhibitors could reduce cell viability to 59% for KMS 18 cell line and 46% for the U-266 cell line. The combined treatment led to a decrease of cell viability to 33% for KMS 18 and 27% for the U-266 cell line, thus showing a significantly better efficacy than the single treatment.
Comparación de perfiles de ansiedad matemática entre estudiantes mexicanos y estudiantes alemanes
(2017)
Se determinan los perfiles de ansiedad matemática de estudiantes mexicanos y estudiantes alemanes por medio de la aplicación de un cuestionario desarrollado ex profeso. La ansiedad matemática se define en términos de tres descriptores: creencias, actitudes y emociones. Los autores definen un Índice de Ansiedad Matemática, al aplicarlo encuentran que los estudiantes alemanes presentan un valor mayor de dicho Índice, lo que significa que tienen una mayor nivel de ansiedad matemática. Las diferencias en los valores del Índice de Ansiedad Matemática se interpretan en términos de diferencias culturales. La interpretación parece ser consistente con las diferencias culturales y se ajusta a los resultados obtenidos.
The technological development of the digital computer and new options to collect, store and transfer mass data have changed the world in the last 40 years. Moreover, due to the ongoing progress of computer power, the establishment of the Internet as critical infrastructure and the options of ubiquitous sensor systems will have a dramatic impact on economies and societies in the future. We give a brief overview about the technological basics especially with regard to the exponential growth of big data and current turn towards sensor-based data collection. From this stance, we reconsider the various dimensions of personal data and and market mechanisms that have an impact of data usage and protection.