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Berufliche Relevanz einer Typ IV-Sensibilisierung gegenüber 1,3-Diphenylguanidin bei Beschäftigten im Gesundheitswesen – ein Update
Get PDFFallberichte berufsdermatologischer Patient*innen mit einer beruflich und klinisch relevanten Typ-IV-Sensibilisierung gegenüber dem Vulkanisationsbeschleuniger 1,3-Diphenylguanidin
Making meaning out of epistemicity markers (and scalars): A psycholinguistic investigation of incremental pragmatic interpretation
Get PDFIn this dissertation, I investigate a central question in the modern inquiry into human language, namely that of how language users interpret utterances as they process them in real time, and what some of the pragmatic principles behind that might be. I juxtapose seemingly disparate themes with the goal of illustrating how pragmatic phenomena – which are incredibly rich and diverse by nature – can be brought together under an account of interpretation as an abductive process of evidence accumulation. My argumentation builds on four
empirical studies focused on the interpretation of scalar expressions (Chapter 2), questions (Chapter 3), discourse particles (Chapter 4), and adjectives (Chapter 5). Taken as a unified collection of explorations on pragmatic processing, these studies contribute to the larger body of work in pragmatics and the language sciences in two significant ways: on the one hand, they provide new empirical insights to long discussed issues in the literature; on the other hand, they extend the theoretical and empirical coverage of experimental research on pragmatics to phenomena which have received little to no attention in the psycholinguistic literature. All in all, I argue that our understanding of linguistic pragmatic phenomena and their cognitive underpinnings can be enriched by construing variability in pragmatic interpretation as a function not only of the degree of conventionalization of the different meanings associated with a linguistic form but also of the potential indexical relation between a form and its meaning (Chapter 6). In doing so, I highlight a still pervasive disconnect in the language sciences, namely that between propositional and non-propositional aspects of language and its use. By exploring from a cognitive standpoint themes which expand the purview of psychologically-oriented research on pragmatics to phenomena more closely related to the intersubjective nature of language use, this work underlines the interconnectedness between form and function in language. Ultimately, it also underlines the importance of looking, even if slightly, beyond the usual dichotomy between denotation and non-referentiality
Precise quantification of forces and charges at the atomic scale by non-contact atomic force and charge force microscopy
Get PDFIn this thesis, four major results novel to the field of NC-AFM, are introduced. First, the force curve alignment (FCA) method, a procedure facilitating the accurate and precise measurement of force curves, free from experimental artefacts and systematic error. Second, the established quantitative AFM theory exclusively considering a tip sampling path parallel to the data recording path is expanded, to describe an arbitrary tip oscillation direction with respect to the data recording path. Third, the theoretical foundation for charge force microscopy (CFM), a method for quantitatively retrieving charges from distant dependent Kelvin probe force microscopy data, is developed. Fourth, the FCA method and CFM in combination are employed experimentally on a cerium dioxide supported gold nanoparticle facilitating the quantification of its static charge state
Textbook English: A Corpus-Based Analysis of the Language of EFL textbooks used in Secondary Schools in France, Germany and Spain
No full textIn secondary English as a Foreign Language (EFL) instructional contexts, textbooks constitute a major and highly influential vector of foreign language input. To date, numerous studies of the language of EFL textbooks have examined textbooks’ representations of one or at most a handful of individual linguistic features each. Taken together, these studies provide valuable insights into “the kind of synthetic English” (Römer 2004a: 185) that pupils are exposed to via their school textbooks. However, the literature review in Chapter 2 makes clear that three crucial aspects have so far been neglected. First, previous research has failed to consider interactions between the frequencies of individual linguistic features. Thus, whilst some influential studies have helped us understand how English learners can be misled by their textbooks into making unidiomatic use of specific linguistic features (e.g., progressive aspect; Römer 2005), only a multivariable approach can paint the full picture as to how “Textbook English” – as a whole – differs from the English that language learners will encounter outside the classroom. Second, prior scholarship has mostly ignored register differences between the various types of texts typically included in school foreign language textbooks. Given that school EFL textbooks frequently feature, for example, extracts from short stories, dialogues, instructions, and exercises on a single double page, this thesis argues that a meaningful analysis of Textbook English requires a register-based approach. Thirdly, previous quantitative corpus-based studies have usually been undertaken at the corpus level, e.g., comparing frequencies across an entire textbook corpus with those from a reference corpus, and have therefore failed to account for the effects of varying textbook proficiency levels or of any potential textbook author, editor, or publisher idiosyncrasies. The present study therefore sets out to describe the linguistic content of secondary school EFL textbooks and to survey the similarities and most striking differences between the various registers of “Textbook English” and naturally occurring English of situationally similar registers with respect to a wide range of lexico-grammatical features. To this end, the Textbook English Corpus (TEC) was compiled. It comprises nine series of secondary school EFL textbooks (42 textbook volumes) used at lower secondary level in France, Germany and Spain and was manually annotated for six text registers: Conversation, Fiction, Informative texts, Instructional language, Personal correspondence and Poetry & rhyme. In addition, three reference corpora (Spoken BNC2014, Info Teens and Youth Fiction) are used as baselines for comparisons between the language of the TEC and the kind of naturally occurring English that learners can be expected to encounter, engage with, and produce themselves outside the EFL classroom. The compilation of the corpora is outlined in Chapter 3. Methodologically, a contrastive corpus-based approach is adopted. Chapter 4 reports on a replication of Römer’s (2005: Ch. 5–6) study on how the progressive aspect is represented in textbook dialogues compared to naturally occurring conversation, extended to a) include lexical and semantic analyses of the verbs featured in the progressive, and b) cover textbook fiction in addition to conversation. In a second in-depth case study, Chapter 5 explores the lexico-grammatical patterns and semantics of the verb MAKE in textbook conversation and fiction as compared to the two corresponding target reference corpora. Both chapters point to notable disparities in the use of these features between the Conversation subcorpus of the TEC and the reference conversation corpus. By contrast, Textbook fiction is shown to present these much more authentically. Chapters 6 and 7 explore the use of multi-dimensional analysis (MDA; Biber 1988; 1995) to model the linguistic specificities of Textbook English. Chapter 6 presents the results of two ‘additive’ MDAs based on Biber’s (1988) model of General Spoken and Written English. The first shows that register accounts for, by far, the greatest proportion of linguistic variation within Textbook English, thus demonstrating that the language of EFL textbooks cannot be adequately modelled without considering register-based variation. By contrast, additional factors such as textbook proficiency level, series, and country of publication/use only play a marginal role in mediating intra-textbook variation. Instructional language is also shown to have very specific linguistic characteristics that set it apart from other textbook registers. The second, contrastive, additive MDA points to a major gap between Textbook Conversation and naturally occurring conversation across all textbook proficiency levels. This is followed by a methodological discussion about the limitations of the traditional MDA framework for the present study. On the basis of these, Chapter 7 proposes a revised MDA framework based on Principal Component Analysis (PCA) and extensive visualisations of the results (inspired by Neumann & Evert 2021). It is trialled with the same data to arrive at a more fine-grained and robust multi-dimensional model of Textbook English. The results of mixed-effects linear regressions modelling the dimension scores of textbook texts and of their corresponding reference corpora largely corroborate those of the two additive MDAs. Together with multi-dimensional visualisations, they are used to explain and illustrate the linguistic specificities of Textbook English. Chapter 8 provides a summary and general discussion of the results of the four analysis chapters. Lexico-grammatical aspects of Textbook English that substantially diverge from the target reference corpora are highlighted with examples before turning to the study’s pedagogical and methodological implications. Suggestions are made as to how teachers, textbook authors and editors could use freely available corpus data and tools to source and modify authentic texts. The case is made for a register approach (see also Rühlemann 2008) to EFL teaching and learning, and implications for teacher training and materials design are discussed. Finally, future research avenues are outlined. These include the triangulation of the present results with learner corpus data to investigate the impact of Textbook English on EFL learners’ productive competences
MRGN-Prävalenz in der normalgesunden Bevölkerung Niedersachsens
Get PDFEinleitung: Über die letzten Jahre haben die Prävalenzen multiresistenter gramnegativer Stäbchenbakterien (MRGN) und daraus resultierenden, eingeschränkt behandelbaren bakteriellen und teils nosokomialen Infektionen weltweit zugenommen. Bisher bekannte MRGN-Quellen wurden durch den Fokus auf bestimmte Risikogruppen belegt. Das Ausmaß der tatsächlichen MRGN-Verbreitung in der asymptomatischen Allgemeinbevölkerung eines Landes ist bis zum jetzigen Zeitpunkt nicht umfassend bekannt. Vermutungen zufolge trägt dieser Bevölkerungsanteil jedoch einen großen Teil zur MRGN-Verbreitung bei. Durch ein unbemerktes MRGN-Trägertum gesunder Personen kann es zur Bakterienübertragung auf Risikopersonen kommen. Bakterielle Infektionen in Kombination mit einem supprimierten Immunsystem oder einer chronischen Erkrankung können für diese Personen lebensbedrohlich werden. Um in Zukunft die erfolgreiche Behandlung einer MRGN-Besiedlung weiterhin gewährleisten zu können, ist die Ermittlung der tatsächlichen MRGN-Verbreitung und -Quellen von hoher Priorität. Aus diesem Grund war das Ziel der vorliegenden Dissertation die Ermittlung der MRGN-Prävalenz in der gesunden Allgemeinbevölkerung Niedersachsens sowie die Identifizierung wesentlicher Risikofaktoren, die zu einer MRGN-Besiedlung führen können.
Materialien & Methoden: 527 Stuhlproben wurden kulturell auf ein MRGN-Vorkommen untersucht. Zusätzlich wurden mittels Fragebogen mögliche Risikofaktoren für eine Bakterienbesiedlung erhoben. Die mikrobiologischen Untersuchungen umfassten neben dem kulturellen MRGN-Nachweis eine Bakterienidentifizierung mittels Matrix-assisted laser desorption time-of-flight-Massenspektrometrie (MALDI-TOF) und die Testung der Antibiotikaempfindlichkeit durch Mikrodilution (Vitek 2). Neben der gängigen statistischen Auswertung wurden erstmalig die Bayes’sche logistische Regression und Poststratifizierung angewandt, um auf Basis der Stichprobe MRGN-Prävalenzen resultierend durch die abgefragten Risikofaktoren für die gesunde Bevölkerung Deutschlands abzuschätzen.
Ergebnisse: 30 (n = 527) Stuhlproben wiesen eine MRGN-Besiedlung mit Escherichia coli (E. coli), Klebsiella pneumoniae oder Citrobacter freundii auf. Dabei dominierte E. coli (n = 28/31, 90,3 %) mit dem Resistenzphänotypen eines ESBL-Produzenten (n = 15/28, 53,6 %) oder mit zusätzlicher Resistenzeigenschaft gegen Fluorchinolone als 3MRGN-Stamm (n = 13/28, 46,4 %). Basierend auf der Stichprobe ergab sich mittels Poststratifizierung angepasst an die Alters- und Geschlechtsstruktur Niedersachsens eine allgemeine MRGN-Prävalenz in der Allgemeinbevölkerung Niedersachsens von 5,9 %.
Bei der Analyse der erhobenen Risikofaktoren ergaben die Bayes’sche logistische Regression und Poststratifizierung starke Assoziationen einer MRGN-Besiedlung mit einem vergangenen Auslandsaufenthalt (OR = 1,69 [0,80; 3,78]) und einer vergangenen Antibiotikaeinnahme (OR = 1,90 [0,9; 3,97]). Es resultierten keine Assoziationen zu einer beruflichen Tätigkeit im Gesundheitswesen (OR = 0,80 [0,38; 1,66]) oder zu einem vergangenen Krankenhausaufenthalt (OR = 0,62 [0,21; 1,58]).
Fazit: Die vorliegende Dissertation liefert aktuelle Hinweise über bislang nicht weiter untersuchte Eintragungswege der MRGN in eine asymptomatische Bevölkerungsgruppe. Dabei scheinen MRGN mit einer ähnlichen Frequenz in dieser Bevölkerungsgruppe verbreitet zu sein, wie sie bereits bei Risikogruppen nachgewiesen wurde. Die vorliegenden Ergebnisse sprechen dafür, dass eine berufliche Tätigkeit im Gesundheitswesen oder ein vergangener Krankenhausaufenthalt eine MRGN-Besiedlung nicht begünstigen im Vergleich zu anderen Faktoren wie einer Antibiotikaeinnahme und einem Auslandsaufenthalt. Des Weiteren lassen die ähnlichen MRGN-Prävalenzen in den Allgemeinbevölkerungen anderer europäischer Länder die Annahme zu, dass eine Besiedlung durch identische Risikofaktoren geschieht. Hinsichtlich der bedeutenden globalen Unterschiede zwischen den Gesundheitssystemen stützt die vorliegende Dissertation die Hypothese, dass die MRGN-Verbreitung einem breiteren Spektrum an Verbreitungswegen folgt als derjenigen von MRSA, dessen Verbreitungsweg eng mit dem Gesundheitssystem assoziiert ist. Darüber hinaus übersteigt die MRGN-Prävalenz in der deutschen Allgemeinbevölkerung die von MRSA, welche bei 0,5 % liegt. Die vorliegenden Ergebnisse geben Anlass für weitere Untersuchungen zu den diversen Eintragungswegen der MRGN. Besonders Maßnahmen im Bereich der Antibiotikaeinnahmen und -verordnungen sowie Auslandsreisen sollten im Fokus zukünftiger Strategien für die MRGN-Bekämpfung und -Eindämmung stehen, da durch deren grenzüberschreitenden Einfluss eine wachsende Rolle der MRGN-Verbreitung zu erwarten ist
Cloud shadow detection and removal for high spatial resolution optical satellite data
Get PDFOptical satellite imagery contain in many cases clouds and cloud shadows, so that an
automated classification of objects on the Earth’s surface is difficult. Therefore, on
the one hand, it is important to create a good cloud and cloud shadow map and, on
the other hand, to correct the shadow areas in such a way that a classification via the
spectral properties of the objects is uniformly possible. Of course, this also includes
the process of atmospheric correction of the optical satellite image data. Especially
for land applications the amount of scenes with usable data is of high importance
due to the exact timing being significant (crop yield estimation) or because the scene
is not free-of-charge and one has to pay for the next acquisition if the current one
contains cloud shadow over the location of interest.
The masking of clouds, cloud shadows, water and snow/ice in optical satellite
imagery is therefore an essential step in automated processing chains.
Furthermore the exact masking of cloud shadows is a very important task prior to
the removal of cloud shadows. Due to the Earth having an annual cloud coverage
of approximately 70%, the contamination of multi-spectral satellite imagery is
inevitable and scientist will have to work with and around this shortcoming.
For this study, the satellite data from the Sentinel-2 mission is used which provides
a five day revisit time at the equator. The swath width of a Sentinel-2 scene is 290
km and the data is acquired in 13 bands with a spatial resolution of 10 m, 20 m and
60 m. For a first comparison of available masking codes, Function of mask (Fmask),
ATCOR and the scene classification of Sen2Cor are evaluated. All three masking
codes use rules that are based on the physical properties such as the Top of Atmosphere
Reflectance (TOA) in order to differentiate clear pixels from cloud pixels.
For the prediction of cloud shadows, the sensor view angle and solar illumination
geometry are used.
Furthermore, a special focus is set on the correct and automatic detection of cloud
shadows. A new method for cloud shadow detection in multi-spectral satellite
images is proposed and compared to current methods. This method is based on
the evaluation of Thresholds, Indices and Projections.
Following the detection of cloud shadows, an improved cloud shadow removal algorithm
is presented for high spatial resolution optical satellite data over land. It is
based on the Matched Filter method which calculates the covariance matrix and a
corresponding zero-reflectance matched filter vector. The new cloud shadow map is
added to the removal of cloud shadows as well as further evaluations performed on
the shadow function to improve the removal algorithm
Convolutional Neural Network Maps Plant Communities in Semi-Natural Grasslands Using Multispectral Unmanned Aerial Vehicle Imagery
No full textSemi-natural grasslands (SNGs) are an essential part of European cultural landscapes. They are an important habitat for many animal and plant species and offer a variety of ecological functions. Diverse plant communities have evolved over time depending on environmental and management factors in grasslands. These different plant communities offer multiple ecosystem services and also have an effect on the forage value of fodder for domestic livestock. However, with increasing intensification in agriculture and the loss of SNGs, the biodiversity of grasslands continues to decline. In this paper, we present a method to spatially classify plant communities in grasslands in order to identify and map plant communities and weed species that occur in a semi-natural meadow. For this, high-resolution multispectral remote sensing data were captured by an unmanned aerial vehicle (UAV) in regular intervals and classified by a convolutional neural network (CNN). As the study area, a heterogeneous semi-natural hay meadow with first- and second-growth vegetation was chosen. Botanical relevés of fixed plots were used as ground truth and independent test data. Accuracies up to 88% on these independent test data were achieved, showing the great potential of the usage of CNNs for plant community mapping in high-resolution UAV data for ecological and agricultural applications
Artificial Intelligence in Personalized E-learning Environments
No full textDigital study assistant systems are software implementations that aim at supporting students throughout their studying endeavor at higher education institutions. In order to do so, digital study assistant systems may rely on technologies from the domain of Artificial Intelligence to maximize their assistance utility. This thesis investigates the feasibility of deploying Artificial Intelligence (AI) algorithms within a digital study assistant system for self-determined learning. This thesis guides the reader through the development process of the SIDDATA digital study assistant system and its AI-driven features. By adhering to data availability constraints and data protection regulations, a general educational resource recommendation system in the form of an artificial neural network based on Google BERT was developed and integrated into the digital study assistant’s feature set. Through a subsequent investigation into the AI-driven feature usage through quantitative and qualitative means, we discover a high perceived potential for AI technologies to incentivize student self-determined learning. Technical and boundary conditional challenges will need to be overcome to realize this potential for all users in future studies
Geopolitics of Lithium
No full textLithium is a silvery-white metal that plays a key role in the decarbonization strategy to fight climate change which includes the development and promotion of electric and hybrid cars with Lithium-ion batteries as energy storage medium. The decarbonization should also significantly reduce the massive capital transfer from the industry states to the oil and gas producers. The rapidly growing lithium demand for Lithium-ion batteries led to intensified exploration activities and an increase of known lithium reserves and resources. Currently, it seems possible to cover the rapidly rising lithium demand by production increases and exploration, but there are various uncertainties as batteries need very high-grade lithium compounds. New mining projects and extraction technologies are uncertain long‐term plans. The recycling quote of batteries is steadily increasing, but lithium recycling is still technically challenging and batteries made from recovered lithium might not have the same quality. In addition, the battery production is dependent from other critical metals like cobalt and nickel as well. The production of minerals such as lithium, cobalt, nickel, and graphite will need to increase by nearly 500% by 2050 to meet the growing demand for clean energy technologies. In the past decade, China has strengthened its geopolitical role by systematic strategic investments and meanwhile produces 60% of the world’s lithium products and 75% of all lithium-ion batteries. It is leading in refining, battery component production, battery assembly, large-scale production in Gigafactories and recycling. In a bigger picture, raw materials as lithium, nickel, cobalt, graphite, copper, and rare earth elements are not only needed for electric and hybrid cars, but are essential for other clean energy products like solar panels and wind turbines as well. China produces more than 70% of the world’s solar modules and has almost 50% of the global wind turbine manufacturing capacity. Another critical strategic issue is the growing energy need for electric and hybrid cars and other clean technologies which may stretch the capacities and stability of electric grids. From the Western perspective, the decarbonization strategy aimed to reduce long-standing dependencies from oil and gas suppliers and to reduce the capital transfer. The situation on the Lithium market shows that the turn to renewable and clean energies creates new dependencies and capital transfers. In summary, lithium is a key resource from an ecological, technical, and geopolitical perspective with many uncertainties for the future
Energy Geopolitics
No full textFor energy security and geopolitics, the control of energy reserves and resources, of transportation routes and critical production steps are essential. This working paper provides an introduction into energy geopolitics by analyzing the control of energy reserves and resources, of transportation routes, critical production steps and the actual topics. If the nation states implement their policies without any further additions, changes or developments, oil, coal, and gas will still dominate the global energy production. The Middle East will keep its position as important oil producer, the year 2030 will definitely not be the time ‘after the oil’. Nuclear energy keeps a small, but stable proportion. Renewable energy production will increase from 74 to 116 Exajoules, but will still be a small proportion of the total energy production of 673 Exajoules in 2030. The energy supply can cover the energy demand, i.e., there will be no ‘energy crisis’. This does not exclude temporary supply crises (e.g., the Russian gas restrictions in 2022). Due to decarbonization policies, the carbon dioxide (CO2) emissions can be stabilized, but will not decline (there are further sources of CO2 emission as well, such as agriculture). The decarbonization will be mainly done by replacing fossil energy with electricity from other sources. The use of renewable energy for electricity is increasing and will be already close to fossil fuels in 2030. But while fossil fuels (oil, gas, coal) will decrease in the global energy mix, even for 2050 a proportion of 60% is expected. Compared to the presented moderate scenario there are more ambitious alternative scenarios in literature based on the Climate Goals from Paris 2015, where renewables will mostly replace all other forms of energy until 2050, but the states already struggle with the energy transformation and the climate goals. The Intergovernmental Panel on Climate Change (IPCC) noted for example that despite progress, adaptation gaps exist, and will continue to grow at current rates of implementation. The World Meteorological Organization (WMO) expects that global warming will reach the 1.5°C level already between 2023 and 2027 with 66% likelihood and not in 2050. The energy transition is not done with the same speed and intensity all over the globe and the production of renewables cannot fill the gaps if fossil fuels would be removed as part of the decarbonization strategy. Due to the size of its population and economy, the leadership of China in many energy sectors could be expected, but its overproportioned control of renewable resource markets and rare earths and critical minerals shows that the turn to renewable and clean energies creates new dependencies and capital transfers for the Western states. Geopolitical topics are the steadily growing influence of China and the Shanghai Cooperation Organization SCO in Central Asia, the European dependency from Russian gas which now requires a massive transformation of energy sources like Liquid Natural Gas (LNG) and the intense competition between United States and China, in particular in the Gulf and MENA region