Comparative research on parking policies in European cities from 2004 to 2014

Veröffentlichung im Rahmen des European Parking Association Congress 2015, Berlin

Development of a practical analytical method for polychlorinated terphenyls known as a group of environmental pollutants

Polychlorierte Terphenyle (PCT) sind persistente, lipophile, schwerflüchtige und bioakkumulierende Substanzen, die offenbar ein hohes toxikologisches Schadpotential aufweisen. Sie sind chemisch wie strukturell eng verwandt mit den polychlorierten Biphenylen und werden fortwährend aus zahlreichen Primär- und Sekundärquellen in die Umwelt emittiert. Im Institut für Ökologische und Nachhaltige Chemie (IÖNC) wurde ein Konzept für ein PCT-Analysenverfahren entwickelt, das den Einsatz von 29 Referenzsubstanzen vorsieht. Nach einem gründlichen säulenchromatographischen Clean-Up können diese durch den Einsatz einer Florisil-Säule abgetrennt und mittels GC/MS gemessen werden. Im Rahmen dieser Arbeit wurden zunächst die fehlenden PCT-Referenzsubstanzen mittels Suzuki-Kupplung erfolgreich synthetisiert und mittels GC/MS, ATR-FTIR- sowie NMR-Spektroskopie charakterisiert. Die experimentell erhaltenen IR-Spektren wurden mit theoretisch berechneten IR-Spektren verglichen. Zudem wurden erste Versuche zur Isotopenmarkierung der Referenzsubstanzen mittels Deuterierung durchgeführt. Im Anschluss erfolgte die Methodenvalidierung mit zum Teil artifiziell hergestellten Brand-, Boden- und Fettproben. Um die Selektivität der Methode zu erreichen, musste zunächst eine GC/MS-Methodenoptimierung vorgenommen werden. Es wurden 2 pg/µL als Nachweisgrenze, 4 pg/µL als Erfassungsgrenze und 6 pg/µL als Bestimmungsgrenze für die PCT-Kongenere in reinem Lösungsmittel mittels der GC/MS-Methode erreicht. Die Messpräzision wurde bestimmt, indem sechsfach GC/MS-Messungen eines 10 pg/µL, 50 pg/µL sowie 100 pg/µL PCT-Mischstandards durchgeführt und jeweils die Variationskoeffizienten ermittelt wurden. Erwartungsgemäß nahm die Messpräzision mit steigender Konzentration zu. Um quantitative Aussagen treffen zu können, wurden insgesamt vier Kalibierreihen genutzt, die alle Kriterien der Linearität erfüllten. Die Analyse der 29 PCT in Gegenwart von analytähnlichen Verbindungen wurde erfolgreich getestet, sodass die Spezifität der Methode gemäß der hier durchgeführten Testreihen gegeben war. Es wurden Wiederfindungsraten zwischen 41% und 139% erzielt mit Variationskoeffizienten zwischen 2,9% und 8,2%. Damit konnte die Methodenvalidierung erfolgreich abgeschlossen werden. Unter den Gesichtspunkten Nachhaltigkeit, Zeit- und Lösemittelersparnis wurde das Abtrennen der 29 PCT durch Verwendung einer Florisil-Säule für die Hochleistungsflüssigchromatographie optimiert.Polychlorinated terphenyls (PCT) are persistent, lipophilic, low volatile and bioaccumulating substances with apparently high toxicological relevance. They are closely related to the polychlorinated biphenyls in structure and chemistry and they are continuously released from numerous primary and secondary sources into the environment. In the Institute of Environmental and Sustainable Chemistry (IÖNC) a concept for a PCT analysis method was developed which included the use of 29 PCT reference substances. The 29 PCT can be measured by GC/MS after an efficient columnchromatographic clean-up and separation by the use of a Florisil column. In this work, at first the missing PCT reference substances were successfully synthesized by Suzuki coupling and then characterized by GC/MS, ATR-FTIR and NMR spectroscopy. The experimentally obtained IR spectra were compared with theoretically calculated IR spectra. In addition, first experiments on the isotope labeling of the reference substances were carried out by deuteration. This was followed by method validation with partially artificially produced combustion, soil and fat samples. In order to achieve selectivity, GC/MS method optimization had to be performed. The following limits in pure solvent were achieved by the GC/MS method: Limit of detection: 2 pg/µL; limit of decision: 4 pg/µL; limit of quantification: 6 pg/µL. The measurement precision was determined by performing six GC/MS measurements with 10 pg/µL, 50 pg/µL and 100 pg/µL PCT mixed standards and calculating the coefficients of variation. As expected, the measurement precision increased with increasing concentration. Four calibration series were used for quantitative analysis which met all criteria of linearity. Analyzing the 29 PCT in the presence of analyte-like compounds was successfully tested. Hereby the specificity of the method was proven according to the test series carried out. Recovery rates between 41% and 139% were achieved with coefficients of variation between 2.9% and 8.2%. The method validation was successfully completed. According to sustainability, time and solvent savings, the separation of 29 PCT was optimized by using a Florisil column for high performance liquid chromatography

AI GOVERNANCE: ARE CHIEF AI OFFICERS AND AI RISK OFFICERS NEEDED?

While AI provides many business opportunities across industries, the organizational implications of AI are still largely unclear. We investigate governance roles related to AI use in practice, and undertake first steps to define the role profiles of a Chief AI Officer (CAIO) and an AI Risk Officer (AIRO). We base our inquiry on two sources: a literature review and evaluative interviews with nine AI professionals from small- and medium-sized companies. We find that, whereas the roles and activities associated with the CAIO and AIRO are commonly deemed relevant for such companies in the long run, today only a few companies have implemented them. Especially the creation of the CAIO position seems justified, due to the complexity of AI and the need for extensive interaction and coordination related to AI governance

Nicht-intendierte Effekte in der Suizidberichterstattung: Der Einfluss von Fußnoten auf die journalistische Qualitätswahrnehmung von Suizidartikeln

Jährlich sterben in Deutschland mehr als 9.000 Menschen durch Suizid. Zu den wichtigsten Präventionsmaßnahmen zählt die Weltgesundheitsorganisation unter anderem auch eine verantwortungsvolle Suizidberichterstattung und bezieht sich damit auf Erkenntnisse zum "Werther-" bzw. "Papageno-Effekt", wonach Suizidberichterstattung zur Entstehung bzw. Verhinderung weiterer Suizide beitragen kann. In der aktuellen Suizidberichterstattung fallen vermehrt Fußnoten am Ende von Artikeln auf, die präventive Hinweise zu Hilfsangeboten bei Suizidgedanken und zur Gefahr von Nachahmungssuiziden enthalten. Allerdings finden sich solche Hinweise auch unter Beiträgen, die wesentliche Elemente aus Suizidpräventionsrichtlinien missachten und somit möglicherweise einen Ersatz für eine dezidierte Auseinandersetzung mit diesen Richtlinien darstellen. In einem Online-Experiment (2x2) bewerteten 212 Journalist*innen in außerredaktioneller Ausbildung einen fiktiven Online-Artikel über einen Prominentensuizid, der im Vorkommen einer Fußnote und der Konformität zu WHO-Richtlinien für Suizidberichterstattung variiert wurde. Die Ergebnisse zeigen, dass der richtlinienkonforme Artikel als sachlicher eingeschätzt wurde, die Fußnote allerdings nicht zum Informationsgehalt beitrug. Für die Publikationsentscheidung des Artikels konnte eine Interaktion festgestellt werden, die aufzeigte, dass unter den Artikeln ohne Fußnote der richtlinienkonforme Artikel eher publiziert werden würde, sich die Artikel mit Fußnote allerdings nicht in der Publikationsentscheidung unterscheiden. Dementsprechend stellt sich die Frage, ob Fußnoten in Redaktionen habitualisiert oder automatisiert als Rechtfertigung von Suizidartikeln verwendet werden, ohne die Hintergründe und Präventionsziele zu kennen.Every year, more than 9,000 people die by suicide in Germany. The World Health Organization considers responsible suicide reporting to be one of the most important preventive measures. This refers to the findings on the "Werther" or "Papageno effect" which show that suicide reporting can contribute to the occurrence or prevention of further suicides. In current suicide media coverage, an increasing number of journalistic footnotes at the end of articles can be observed which refer to offers of support and help in case of suicidal thoughts and/or inform about the risk of copycat suicides after irresponsible media coverage. However, such references are also found among articles that don’t take key elements of suicide prevention guidelines in account, potentially serving as a substitute for a detailed look at these guidelines. In an online experiment (2x2), 212 journalists in training with work experience evaluated a fictional online article about a celebrity suicide that was varied in the occurrence of a footnote and conformity to WHO guidelines for suicide reporting with respect to its (journalistic) quality and their professional willingness to publish it. The results show that the guideline-compliant article was judged to be more objective, although the footnote itself did not contribute to the information value. For the journalistic intention to publish the article, an interaction was found that revealed that among the articles without a footnote, the guideline-compliant article was more likely to be published. In contrast, publication intention did not differ for the articles that contained a footnote. Accordingly, the question arises whether footnotes are habitually or automatically used in editorial offices as a justification for suicide articles showing a lack of knowledge of the empirical background and common prevention goals

Simulated and observed horizontal inhomogeneities of optical thickness of Arctic stratus

Two-dimensional horizontal fields of cloud optical thickness τ derived from airborne measurements of solar spectral, cloud-reflected radiance are compared with semi-idealized large eddy simulations (LESs) of Arctic stratus performed with the Consortium for Small-scale Modeling (COSMO) atmospheric model. The measurements were collected during the Vertical Distribution of Ice in Arctic Clouds (VERDI) campaign carried out in Inuvik, Canada, in April/May 2012. The input for the LESs is obtained from collocated airborne dropsonde observations of a persistent Arctic stratus above the sea-ice-free Beaufort Sea. Simulations are performed for spatial resolutions of 50m (1.6km × 1.6km domain) and 100m (6.4km × 6.4km domain). Macrophysical cloud properties, such as cloud top altitude and vertical extent, are well captured by the COSMO simulations. However, COSMO produces rather homogeneous clouds compared to the measurements, in particular for the simulations with coarser spatial resolution. For both spatial resolutions, the directional structure of the cloud inhomogeneity is well represented by the model. Differences between the individual cases are mainly associated with the wind shear near cloud top and the vertical structure of the atmospheric boundary layer. A sensitivity study changing the wind velocity in COSMO by a vertically constant scaling factor shows that the directional, small-scale cloud inhomogeneity structures can range from 250 to 800m, depending on the mean wind speed, if the simulated domain is large enough to capture also large-scale structures, which then influence the small-scale structures. For those cases, a threshold wind velocity is identified, which determines when the cloud inhomogeneity stops increasing with increasing wind velocity

Two-photon excited LIF determination of H-atom concentrations near a heated filament in a low pressure H2 environment

Meier U, Kohse-Höinghaus K, Schäfer L, Klages C-P. Two-photon excited LIF determination of H-atom concentrations near a heated filament in a low pressure H2 environment. Applied Optics. 1990;29(33):4993-4999.With respect to the investigation of low pressure filament-assisted chemical vapor deposition processes for diamond formation, absolute concentrations of atomic hydrogen were determined by two-photon laserinduced fluorescence in the vicinity of a heated filament in an environment containing H2 or mixtures of H2 and CH4. Radial H concentration profiles were obtained for different pressures and filament temperatures, diameters, and materials. The influence of the addition of various amounts of methane on the H atom concentrations was examined

Bericht zum Mobilitätsverhalten an der Frankfurt University of Applied Sciences

Eine Arbeit der Fachgruppe Neue Mobilität der Frankfurt UAS

Leveraging the Power of Peer Groups for Refugee Integration

Refugee integration, one long-term solution to the large number of people fleeing their home countries, constitutes a challenge for both refugees and host societies. ICT and especially online peer groups seem promising to support this process. Building on literature demonstrating the societal benefits of peer groups, this paper proposes a novel peer-group-based approach to address refugee integration and introduces both an online and offline realization. A randomized field experiment in cooperation with public (refugee) services and a non-governmental organization makes it possible to expand existing research by quantitatively demonstrating societal benefits of online peer groups and ICT for refugee integration. Further, this paper is the first to assess the effectiveness of online and offline peer groups in one experimental setup comparatively. Results show that peer groups provide substantial value with respect to the integration domains social bridges, social bonds, rights and citizenship as well as safety and stability. While the outcome of the various integration domains differs for online and offline peer groups, participants’ adoption rates were higher for online peer groups

Graph4Med: a web application and a graph database for visualizing and analyzing medical databases

Background: Medical databases normally contain large amounts of data in a variety of forms. Although they grant significant insights into diagnosis and treatment, implementing data exploration into current medical databases is challenging since these are often based on a relational schema and cannot be used to easily extract information for cohort analysis and visualization. As a consequence, valuable information regarding cohort distribution or patient similarity may be missed. With the rapid advancement of biomedical technologies, new forms of data from methods such as Next Generation Sequencing (NGS) or chromosome microarray (array CGH) are constantly being generated; hence it can be expected that the amount and complexity of medical data will rise and bring relational database systems to a limit. Description: We present Graph4Med, a web application that relies on a graph database obtained by transforming a relational database. Graph4Med provides a straightforward visualization and analysis of a selected patient cohort. Our use case is a database of pediatric Acute Lymphoblastic Leukemia (ALL). Along routine patients’ health records it also contains results of latest technologies such as NGS data. We developed a suitable graph data schema to convert the relational data into a graph data structure and store it in Neo4j. We used NeoDash to build a dashboard for querying and displaying patients’ cohort analysis. This way our tool (1) quickly displays the overview of patients’ cohort information such as distributions of gender, age, mutations (fusions), diagnosis; (2) provides mutation (fusion) based similarity search and display in a maneuverable graph; (3) generates an interactive graph of any selected patient and facilitates the identification of interesting patterns among patients. Conclusion: We demonstrate the feasibility and advantages of a graph database for storing and querying medical databases. Our dashboard allows a fast and interactive analysis and visualization of complex medical data. It is especially useful for patients similarity search based on mutations (fusions), of which vast amounts of data have been generated by NGS in recent years. It can discover relationships and patterns in patients cohorts that are normally hard to grasp. Expanding Graph4Med to more medical databases will bring novel insights into diagnostic and research