Morphologische Veränderungen in der Mausnetzhaut nach Ischämie/Reperfusion in verschiedenen genetisch veränderten Mauslinien

Müllerzellen - die dominierenden Gliazellen der Netzhaut - üben vielfältige Funktionen und Aufgaben im retinalen „Zellnetzwerk“ aus. Ihre wohl wichtigste Funktion ist die Aufrechterhaltung der Volumen- und Ionenhomöostase der Retina. Forschungsergebnisse der letzten Jahre deuten darauf hin, dass pathologische Veränderungen in der Volumenregulation von Müllerzellen bei vielen Erkrankungen der Netzhaut eine bedeutende Rolle spielen. Diese Promotionsarbeit befasst sich mit morphologischen Veränderungen in der Netzhaut von Wildtypmäusen sowie von drei Mausstämmen mit genetischen Veränderungen (Überexpression von dnSNARE, P2Y1-defizient, IP3-R2-defizient) unter pathologischen Bedingungen. In den experimentellen Untersuchungen fand das in Vorarbeiten bereits etablierte Ischämie-Reperfusions-Modell Anwendung. Es ist bekannt, dass Müllerzellen nach retinaler Ischämie Veränderungen durchmachen, die als reaktive Gliose bezeichnet werden. Reaktive Müllerzellen sind nicht mehr in der Lage, bestimmte Funktionen zu erfüllen, die sie in der gesunden Netzhaut haben, dazu gehört eine Einschränkung der Fähigkeit zur Volumenregulation. Ziel der Arbeit war es erstens, eine Charakterisierung der Mausnetzhäute hinsichtlich der zellulären Zusammensetzung der Retina vorzunehmen und zweitens zu untersuchen, inwiefern sich eine Störung der Müllerzellfunktion – wie sie bei allen drei genetisch veränderten Mauslinien vorliegt – auf das Überleben der Nervenzellen unter extremen Stressbedingungen wie z.B. einer Ischämie auswirkt. Denn gerade unter den mit einer Ischämie einhergehenden Bedingungen sollte die Funktion der Müllerzellen zum Erhalt der retinalen Ionen- und Volumenhomöostase von entscheidender Bedeutung sein

Erfassen von Nachhaltigkeit in der Hochschulforschung : eine Analyse von Hochschulen im DACH Raum

An increasing number of universities write sustainability reports with a partial focus on research. This study therefore explores, with literature research and 14 interviews, how many universities deal with sustainability in research, how sustainability in research can be defined and how it is recorded by the universities. In the sustainability reports, no or no uniform recording methods are used for sustainability in research. A definitive definition of sustainability in research could not be found, but in this paper a distinction between relations to or focus on sustainability for research is proposed. In just under half of the sustainability reports examined, coverage methods for sustainability in research are used, although these differ greatly from one another. The most commonly used method is SDG mapping, in which research projects or publications are assigned to corresponding SDGs. In this way, sustainability relation can be identified and communicated in research. The error rate in SDG mapping is high, so transparent communication is necessary to show the limitations of the method. Other recommended data collection methods and indicators are targeted project funding, junior researcher funding, SD mapping, ethics committees, spin-offs, networking events, national and international collaboration and networking centres.Eine steigende Anzahl von Hochschulen erstellt Nachhaltigkeitsberichte mit Teilfokus auf Forschung. Die vorliegende Arbeit untersucht deshalb explorativ mit Literaturrecherche und 14 Interviews, wie viele Hochschulen sich mit Nachhaltigkeit in der Forschung befassen, wie sich Nachhaltigkeit in der Forschung definieren lässt und wie dies von den Hochschulen erfasst wird. In den Nachhaltigkeitsberichten werden keine oder keine einheitlichen Erfassungsmethoden für Nachhaltigkeit in der Forschung verwendet. Eine endgültige Definition von Nachhaltigkeit in der Forschung konnte nicht gefunden werden, doch in dieser Arbeit wird eine Unterscheidung zwischen Nachhaltigkeitsbezug und Nachhaltigkeitsschwerpunkt für die Forschung vorgeschlagen. In knapp der Hälfte der untersuchten Nachhaltigkeitsberichte werden Erfassungsmethoden für Nachhaltigkeit in der Forschung verwendet, wobei sich diese stark voneinander unterscheiden. Die meistverwendete Erfassungsmethode ist das SDG Mapping, bei welchem Forschungsprojekte oder Publikationen den entsprechenden SDGs zugeordnet werden. Dadurch können Nachhaltigkeitsbezüge in der Forschung identifiziert und kommuniziert werden. Die Fehlerquote beim SDG Mapping ist hoch, daher ist eine transparente Kommunikation erforderlich, um die Limitationen der Methode aufzuzeigen. Andere empfehlenswerte Erfassungsmethoden und Indikatoren sind gezielte Projektförderungen, Nachwuchsförderungen, SD Mapping, Ethikkommissionen, Spin-offs, Vernetzungsanlässe, nationale und internationale Kollaboration und Vernetzungszentren

Crowdsourcing Ecologically-Valid Dialogue Data for German

Despite their increasing success, user interactions with smart speech assistants (SAs) are still very limited compared to human-human dialogue. One way to make SA interactions more natural is to train the underlying natural language processing modules on data which reflects how humans would talk to a SA if it was capable of understanding and producing natural dialogue given a specific task. Such data can be collected applying a Wizard-of-Oz approach (WOz), where user and system side are played by humans. WOz allows researchers to simulate human-machine interaction while benefitting from the fact that all participants are human and thus dialogue-competent. More recent approaches have leveraged simple templates specifying a dialogue scenario for crowdsourcing large-scale datasets. Template-based collection efforts, however, come at the cost of data diversity and naturalness. We present a method to crowdsource dialogue data for the SA domain in the WOz framework, which aims at limiting researcher-induced bias in the data while still allowing for a low-resource, scalable data collection. Our method can also be applied to languages other than English (in our case German), for which fewer crowd-workers may be available. We collected data asynchronously, relying only on existing functionalities of Amazon Mechanical Turk, by formulating the task as a dialogue continuation task. Coherence in dialogues is ensured, as crowd-workers always read the dialogue history, and as a unifying scenario is provided for each dialogue. In order to limit bias in the data, rather than using template-based scenarios, we handcrafted situated scenarios which aimed at not pre-script-ing the task into every single detail and not priming the participants’ lexical choices. Our scenarios cued people’s knowledge of common situations and entities relevant for our task, without directly mentioning them, but relying on vague language and circumlocutions. We compare our data (which we publish as the CROWDSS corpus; n = 113 dialogues) with data from MultiWOZ, showing that our scenario approach led to considerably less scripting and priming and thus more ecologically-valid dialogue data. This suggests that small investments in the collection setup can go a long way in improving data quality, even in a low-resource setup

Potential and nutritional properties of local food plants from Angola to combat malnutrition − suitable alternatives to frequently cultivated crops

The human diet of the local population in the province Uíge, Angola mainly consists of carbohydrate rich plants originating from America or Asia. Acidic soils lead to various deficiency syndromes and low livestock yield. The aim of this study is to evaluate the nutritional potential of 14 native plants from Africa (Aframomum alboviolaceum, Aframomum angustifolium, Aframomum giganteum, Antidesma venosum, Clitandra cymulosa, Landolphia buchananii, Landolphia lanceolata, Landolphia owariensis, Oncoba welwitschii, Parinari capensis, Piper umbellatum, Pseudospondias microcarpa, Tristemma mauritianum, Vitex madiensis subsp. madiensis). The amino acid composition, beta-carotene, vitamin B1, B2, C and E content was determined for the respective edible plant part. Fruits of P. capensis were found to be rich in beta-carotene. The pulp of O. welwitschii shows a high nutritional value (high in vitamin B1, B2, C, E and in indispensable amino acids). Leaves of P. umbellatum are determined as convenient substitutes for the human nutrition containing beta-carotene, vitamin B1, B2, C and E. The integration and cultivation of studied plants indicate positive health effects, supplying different amounts of frequently lacking vitamins and beneficial ratios of indispensable amino acids. Studies examining dependencies between site location, ripeness, storage or transportation are urgently needed as they directly influence the micronutrient content

Potential and nutritional properties of local food plants from Angola to combat malnutrition − suitable alternatives to frequently cultivated crops

The human diet of the local population in the province Uíge, Angola mainly consists of carbohydrate rich plants originating from America or Asia. Acidic soils lead to various deficiency syndromes and low livestock yield. The aim of this study is to evaluate the nutritional potential of 14 native plants from Africa (Aframomum alboviolaceum, Aframomum angustifolium, Aframomum giganteum, Antidesma venosum, Clitandra cymulosa, Landolphia buchananii, Landolphia lanceolata, Landolphia owariensis, Oncoba welwitschii, Parinari capensis, Piper umbellatum, Pseudospondias microcarpa, Tristemma mauritianum, Vitex madiensis subsp. madiensis). The amino acid composition, beta-carotene, vitamin B1, B2, C and E content was determined for the respective edible plant part. Fruits of P. capensis were found to be rich in beta-carotene. The pulp of O. welwitschii shows a high nutritional value (high in vitamin B1, B2, C, E and in indispensable amino acids). Leaves of P. umbellatum are determined as convenient substitutes for the human nutrition containing beta-carotene, vitamin B1, B2, C and E. The integration and cultivation of studied plants indicate positive health effects, supplying different amounts of frequently lacking vitamins and beneficial ratios of indispensable amino acids. Studies examining dependencies between site location, ripeness, storage or transportation are urgently needed as they directly influence the micronutrient content

Mechanical stability limits of bi-layer thermal barrier coatings

Thermal barrier coatings based on yttria stabilized zirconia (YSZ) have reached a state in development, where a further increase in lifetime and/or maximum operating temperature has become more and more difficult. Nevertheless, the demand for even higher operating temperatures is persisting, and it is pushing the YSZ-based thermal barrier coatings to and beyond their limit. Especially phase instabilities of YSZ at temperatures above 1200°C lead to a fast deterioration of the ceramic top coating. Consequently, the search for new materials with low thermal conductivity, relatively low coefficient of thermal expansion and phase stability at temperatures well above 1200°C was started, to replace YSZ as the top layer material [1;2]. Among the candidates, gadolinium zirconate (Gd2Zr2O7, GZO) and lanthanum zirconate (La2Zr2O7, LZO) have proven to be viable choices; however, the fracture toughness of these materials is considerably lower than that of YSZ which results in a lower strain tolerance and early failure of single-layered coatings [3]. It is therefore advantageous to create bi-layered coatings, where a top-layer of GZO or LZO is sprayed on a layer of standard YSZ material. As a result, the lower part of the TBC remains a state-of-the-art TBC system and can benefit from the experience with YSZ-TBCs gained so far. The mechanical aspects of such bi-layered ceramic structures have up to now not been investigated in detail. Especially the maximum tolerable load or the corresponding failure strain of the thermal barrier coating is of great interest. This is primarily to ensure that the TBC will not fail during normal operation of the plant. In this work 4-point bend testing with in-situ acoustic emission measurement was used to determine the critical strain to failure of APS bi-layer TBCs based on GZO/YSZ-ceramic. Isothermal oxidation of the specimens was performed at 1050°C and 1100°C, respectively. The use of the acoustic emission technology enables the distinction of individual failure modes in the bi-layer coating. As an example, figure 1 shows the stress-strain-curve and the acoustic emission signal of a bi-layer TBC after isothermal oxidation for 100h at 1050°C. As can be seen from the figure, the top GZO-layer fails prior to failure of the bottom YSZ-layer. The critical strain values are also used to establish a fracture mechanics-based lifetime model. The model delineates areas of safe operation from areas where failure of the TBC system is imminent. Furthermore it can be distinguished between failure of the GZO-layer or the YSZ-layer

Line-field optical coherence tomography: in\ua0vivo diagnosis of basal cell carcinoma subtypes compared with histopathology

Background: Basal cell carcinoma (BCC) is the most common skin cancer in the general population. Treatments vary from Mohs surgery to topical therapy, depending on the subtype. Dermoscopy, reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) have gained a foothold in daily clinical practice to optimize diagnosis and subtype-oriented treatment. The new technique of line-field confocal OCT (LC-OCT) allows imaging at high resolution and depth, but its use has not yet been investigated in larger studies. Aim: To evaluate the main LC-OCT criteria for the diagnosis and subtyping of BCC compared with histopathology, OCT and RCM. Methods: In total, 52 histopathologically confirmed BCCs were evaluated for imaging criteria. Their frequency, predictive values and ROC curves were calculated. A multinominal regression with stepwise variables selection to distinguish BCC subtypes was performed. Results: Nodular BCCs were mainly characterized by atypical keratinocytes, altered dermoepidermal junction (DEJ), tumour nests in the dermis, dark clefting, prominent vascularization and white hyper-reflective stroma. Superficial BCCs showed a thickening of the epidermis due to a series of tumour lobules with clear connection to the DEJ (string of pearls pattern). Infiltrative BCCs were characterized by elongated hyporeflective tumour strands, surrounded by bright collagen (shoal of fish pattern). The overall BCC subtype agreement between LC-OCT and conventional histology was 90.4% (95% CI 79.0\u201396.8). Conclusion: LC-OCT allows noninvasive, real-time identification of BCCs and their subtypes in vertical, horizontal and three-dimension mode compared with histology, RCM and OCT. Further larger studies are needed to better explore the clinical applications of this promising device

Methods to Elicit Forecasts from Groups: Delphi and Prediction Markets Compared

Traditional groups meetings are an inefficient and ineffective method for making forecasts and decisions. We compare two structured alternatives to traditional meetings: the Delphi technique and prediction markets. Delphi is relatively simple and cheap to implement and has been adopted for diverse applications in business and government since its origins in the 1950s. It can be used for nearly any forecasting, estimation, or decision making problem not barred by complexity or ignorance. While prediction markets were used more than a century ago, their popularity waned until more recent times. Prediction markets can be run continuously, and they motivate participation and participants to reveal their true beliefs. On the other hand, they need many participants and clear outcomes in order to determine pay-offs. Moreover, translating knowledge into a price is not intuitive to everyone and constructing contracts that will provide a useful forecast may not be possible for some problems. It is difficult to maintain confidentiality with markets and they are vulnerable to manipulation. Delphi is designed to reveal panelists’ knowledge and opinions via their forecasts and the reasoning they provide. This format allows testing of knowledge and learning by panelists as they refine their forecasts but may also lead to conformity due to group pressure. The reasoning provided as an output of the Delphi process is likely to be reassuring to forecast users who are uncomfortable with the “black box” nature of prediction markets. We consider that, half a century after its original development, Delphi is under-utilized