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Transitional Justice
(2022)
This publication deals with the topic of transitional justice. In six case studies, the authors link theoretical and practical implications in order to develop some innovative approaches. Their proposals might help to deal more effectively with the transition of societies, legal orders and political systems.
Young academics from various backgrounds provide fresh insights and demonstrate the relevance of the topic. The chapters analyse transitions and conflicts in Sierra Leone, Argentina, Nicaragua, Nepal, and South Sudan as well as Germany’s colonial genocide in Namibia. Thus, the book provides the reader with new insights and contributes to the ongoing debate about transitional justice.
Studies from several countries suggest that COVID-19 vaccination rates are lower among migrants compared to the general population. Urgent calls have been made to improve vaccine outreach to migrants, however, there is limited evidence on effective approaches, especially using social media. We assessed a targeted, low-cost, Facebook campaign disseminating COVID-19 vaccine information among Arabic, Turkish and Russian speakers in Germany (N = 888,994). As part of the campaign, we conducted two randomized, online experiments to assess the impact of the advertisement (1) language and (2) depicted messenger (government authority, religious leader, doctor or family). Key outcomes included reach, click-through rates, conversion rates and cost-effectiveness. Within 29 days, the campaign reached 890 thousand Facebook users. On average, 2.3 individuals accessed the advertised COVID-19 vaccination appointment tool for every euro spent on the campaign. Migrants were 2.4 (Arabic), 1.8 (Russian) and 1.2 (Turkish) times more likely to click on advertisements translated to their native language compared to German-language advertisements. Furthermore, findings showed that government representatives can be more successful in engaging migrants online compared to other messengers, despite common claims of lower trust in government institutions among migrants. This study highlights the potential of tailored, and translated, vaccination campaigns on social media for reaching migrants who may be left out by traditional media campaigns.
Gruppierung von Daten
(2022)
Dieser Beitrag beinhaltet einen Vergleich zwischen den Methoden der Topologischen Datenanalyse (TDA) und statistischen Clusterverfahren bei der Gruppierung von Daten. Es werden Gemeinsamkeiten und Unterschiede bei der Bildung der Cluster und Zuordnung der statistischen Einheiten identifiziert. Hierzu werden zwei empirische Datensätze aus der Biologie und Medizin herangezogen.
Zusammengefasst haben sich die Verfahren der TDA als ein praktikables Werkzeug bei der Gruppierung von Objekten erwiesen. Vor allem mit dem Mapper-Algorithmus konnten adäquate Cluster erkannt werden. Beim Iris Flower-Datensatz hat die TDA ähnliche Ergebnisse wie die Clusteranalyse erzielt. Der Heart Disease-Datensatz war schwieriger zu behandeln. Die genutzten clusteranalytischen Verfahren waren nicht geeignet, die beiden Gruppen von Patienten korrekt zu identifizieren. Im Vergleich zu den Standardverfahren der Clusteranalyse zeigte sich eine leichte Überlegenheit der topologischen Verfahren.
Le Président de la République française, Emmanuel Macron, a prononcé le 26 septembre 2017 dans le grand auditorium de l’Université de la Sorbonne devant un public composé d’étudiants et de responsables politiques un ambitieux discours sur l’Europe. Parmi ses « initiatives pour l’Europe » figure la création d’universités européennes.
L’objectif de cette étude est de mettre en lumière l’héritage et les apports français et allemands dans ce nouveau modèle de partenariat européen en construction. Quel est le rôle joué par le niveau ministériel en France et en Allemagne dans le cadre de la mise en œuvre de l’initiative ? Quel est le degré et quelle est la nature d’intervention des Agences nationales Erasmus dans chacun des deux pays ? Quel est le positionnement de l’Université franco-allemande par rapport à ces nouvelles alliances ainsi que sa contribution ? À partir de trois exemples, à savoir les alliances ECIU, EPICUR et FORTHM, nous illustrons comment la coopération franco-allemande ainsi que les relations transfrontalières développées au sein de réseaux préexistants alimentent ces « réseaux des réseaux ».
Ce mémoire puise ses principales sources de 15 entretiens semi-directifs, menés entre août 2020 et janvier 2021 auprès d’acteurs allemands, français et européens. La richesse de leur expertise nourrit la conclusion dans laquelle nous tentons de mettre en exergue la dimension franco-allemande de cette initiative. Avec un regard franco-allemand, nous proposons un résumé des actuelles forces, opportunités, faiblesses et menaces qui favorisent ou entravent le développement de cette nouvelle initiative.
Der Präsident der französischen Republik, Emmanuel Macron, hielt am 26. September 2017 im großen Hörsaal der Universität Sorbonne vor einem Publikum aus Studenten und Politikern eine ambitionierte Rede zu Europa. Zu seinen "Initiativen für Europa" gehört die Schaffung von Europäischen Hochschulnetzwerken.
Das Ziel dieser Masterarbeit besteht darin, das deutsch-französische Erbe sowie die Beiträge beider Länder in diesen neuen Modellen zu untersuchen :.Welche Rolle spielt die ministerielle Ebene in Frankreich und Deutschland bei der Umsetzung der Initiative? In welchem Umfang und auf welche Art und Weise beteiligen sich die nationalen Erasmus-Agenturen in beiden Ländern ? Welche Position nimmt die Deutsch-Französische Hochschule in Bezug auf diese neuen Allianzen ein und welche Unterstützung bietet sie? Anhand von drei Beispielen, den Allianzen ECIU, EPICUR und FORTHM, wird beschrieben, welche Beiträge die deutsch-französische Zusammenarbeit sowie grenzüberschreitende Kooperationen leisten.
Die Hauptquellen für diese Masterarbeit stellen 15 semidirektive Experteninterviews dar, die zwischen August 2020 und Januar 2021 mit deutschen, französischen und europäischen Akteuren geführt wurden. Der Reichtum ihrer Expertise fließt in die Schlussfolgerung ein, in der wir versuchen, die deutsch-französische Dimension dieser Initiative hervorzuheben. Mit einer deutsch-französischen Perspektive versuchen wir, die Stärken, Chancen, Schwächen und Bedrohungen zusammenzufassen, die die Entwicklung dieser neuen Initiative begünstigen oder behindern.
The President of the French Republic, Emmanuel Macron, gave an ambitious speech on Europe to an audience of students and politicians in the large lecture hall of the Sorbonne University on 26 September 2017. Among his "Initiatives for Europe" is the creation of European University Networks.
The aim of this Master's thesis is to examine the Franco-German heritage and the contributions of both countries in these new models :.What is the role of the ministerial level in France and Germany in the implementation of the initiative? To what extent and in what way do the national Erasmus agencies in both countries participate ? What is the position of the Franco-German University in relation to these new alliances and what support does it offer? Using three examples, the ECIU, EPICUR and FORTHM alliances, the contributions of Franco-German cooperation and cross-border cooperation are described.
The main sources for this Master's thesis are 15 semi-directive expert interviews conducted with German, French and European actors between August 2020 and January 2021. The wealth of their expertise feeds into the conclusion, in which we try to highlight the Franco-German dimension of this initiative. With a Franco-German perspective, we try to summarise the strengths, opportunities, weaknesses and threats that favour or hinder the development of this new initiative.
This dissertation aimed to determine differential expressed miRNAs in the context of chronic pain in polyneuropathy. For this purpose, patients with chronic painful polyneuropathy were compared with age matched healthy patients. Taken together, all miRNA pre library preparation quality controls were successful and none of the samples was identified as an outlier or excluded for library preparation. Pre sequencing quality control showed that library preparation worked for all samples as well as that all samples were free of adapter dimers after BluePippin size selection and reached the minimum molarity for further processing. Thus, all samples were subjected to sequencing. The sequencing control parameters were in their optimal range and resulted in valid sequencing results with strong sample to sample correlation for all samples. The resulting FASTQ file of each miRNA library was analyzed and used to perform a differential expression analysis. The differentially expressed and filtered miRNAs were subjected to miRDB to perform a target prediction. Three of those four miRNAs were downregulated: hsa-miR-3135b, hsa-miR-584-5p and hsa-miR-12136, while one was upregulated: hsa-miR-550a-3p. miRNA target prediction showed that chronic pain in polyneuropathy might be the result of a combination of miRNA mediated high blood flow/pressure and neural activity dysregulations/disbalances. Thus, leading to the promising conclusion that these four miRNAs could serve as potential biomarkers for the diagnosis of chronic pain in polyneuropathy.
Since TRPV1 seems to be one of the major contributors of nociception and is associated with neuropathic pain, the influence of PKA phosphorylated ARMS on the sensitivity of TRPV1 as well as the part of AKAP79 during PKA phosphorylation of ARMS was characterized. Therefore, possible PKA-sites in the sequence of ARMS were identified. This revealed five canonical PKA-sites: S882, T903, S1251/52, S1439/40 and S1526/27. The single PKA-site mutants of ARMS revealed that PKA-mediated ARMS phosphorylation seems not to influence the interaction rate of TRPV1/ARMS. While phosphorylation of ARMST903 does not increase the interaction rate with TRPV1, ARMSS1526/27 is probably not phosphorylated and leads to an increased interaction rate. The calcium flux measurements indicated that the higher the interaction rate of TRPV1/ARMS, the lower the EC50 for capsaicin of TRPV1, independent of the PKA phosphorylation status of ARMS. In addition, the western blot analysis confirmed the previously observed TRPV1/ARMS interaction. More importantly, AKAP79 seems to be involved in the TRPV1/ARMS/PKA signaling complex. To overcome the problem of ARMS-mediated TRPV1 sensitization by interaction, ARMS was silenced by shRNA. ARMS silencing resulted in a restored TRPV1 desensitization without affecting the TRPV1 expression and therefore could be used as new topical therapeutic analgesic alternative to stop ARMS mediated TRPV1 sensitization.
A decade ago, it became feasible to store multi-terabyte databases in main memory. These in-memory databases (IMDBs) profit from DRAM's low latency and high throughput as well as from the removal of costly abstractions used in disk-based systems, such as the buffer cache. However, as the DRAM technology approaches physical limits, scaling these databases becomes difficult. Non-volatile memory (NVM) addresses this challenge. This new type of memory is persistent, has more capacity than DRAM (4x), and does not suffer from its density-inhibiting limitations. Yet, as NVM has a higher latency (5-15x) and a lower throughput (0.35x), it cannot fully replace DRAM.
IMDBs thus need to navigate the trade-off between the two memory tiers. We present a solution to this optimization problem. Leveraging information about access frequencies and patterns, our solution utilizes NVM's additional capacity while minimizing the associated access costs. Unlike buffer cache-based implementations, our tiering abstraction does not add any costs when reading data from DRAM. As such, it can act as a drop-in replacement for existing IMDBs. Our contributions are as follows:
(1) As the foundation for our research, we present Hyrise, an open-source, columnar IMDB that we re-engineered and re-wrote from scratch. Hyrise enables realistic end-to-end benchmarks of SQL workloads and offers query performance which is competitive with other research and commercial systems. At the same time, Hyrise is easy to understand and modify as repeatedly demonstrated by its uses in research and teaching.
(2) We present a novel memory management framework for different memory and storage tiers. By encapsulating the allocation and access methods of these tiers, we enable existing data structures to be stored on different tiers with no modifications to their implementation. Besides DRAM and NVM, we also support and evaluate SSDs and have made provisions for upcoming technologies such as disaggregated memory.
(3) To identify the parts of the data that can be moved to (s)lower tiers with little performance impact, we present a tracking method that identifies access skew both in the row and column dimensions and that detects patterns within consecutive accesses. Unlike existing methods that have substantial associated costs, our access counters exhibit no identifiable overhead in standard benchmarks despite their increased accuracy.
(4) Finally, we introduce a tiering algorithm that optimizes the data placement for a given memory budget. In the TPC-H benchmark, this allows us to move 90% of the data to NVM while the throughput is reduced by only 10.8% and the query latency is increased by 11.6%. With this, we outperform approaches that ignore the workload's access skew and access patterns and increase the query latency by 20% or more.
Individually, our contributions provide novel approaches to current challenges in systems engineering and database research. Combining them allows IMDBs to scale past the limits of DRAM while continuing to profit from the benefits of in-memory computing.
Subdividing space through interfaces leads to many space partitions that are relevant to soft matter self-assembly. Prominent examples include cellular media, e.g. soap froths, which are bubbles of air separated by interfaces of soap and water, but also more complex partitions such as bicontinuous minimal surfaces.
Using computer simulations, this thesis analyses soft matter systems in terms of the relationship between the physical forces between the system's constituents and the structure of the resulting interfaces or partitions. The focus is on two systems, copolymeric self-assembly and the so-called Quantizer problem, where the driving force of structure formation, the minimisation of the free-energy, is an interplay of surface area minimisation and stretching contributions, favouring cells of uniform thickness.
In the first part of the thesis we address copolymeric phase formation with sharp interfaces. We analyse a columnar copolymer system "forced" to assemble on a spherical surface, where the perfect solution, the hexagonal tiling, is topologically prohibited. For a system of three-armed copolymers, the resulting structure is described by solutions of the so-called Thomson problem, the search of minimal energy configurations of repelling charges on a sphere. We find three intertwined Thomson problem solutions on a single sphere, occurring at a probability depending on the radius of the substrate.
We then investigate the formation of amorphous and crystalline structures in the Quantizer system, a particulate model with an energy functional without surface tension that favours spherical cells of equal size. We find that quasi-static equilibrium cooling allows the Quantizer system to crystallise into a BCC ground state, whereas quenching and non-equilibrium cooling, i.e. cooling at slower rates then quenching, leads to an approximately hyperuniform, amorphous state. The assumed universality of the latter, i.e. independence of energy minimisation method or initial configuration, is strengthened by our results. We expand the Quantizer system by introducing interface tension, creating a model that we find to mimic polymeric micelle systems: An order-disorder phase transition is observed with a stable Frank-Caspar phase.
The second part considers bicontinuous partitions of space into two network-like domains, and introduces an open-source tool for the identification of structures in electron microscopy images. We expand a method of matching experimentally accessible projections with computed projections of potential structures, introduced by Deng and Mieczkowski (1998). The computed structures are modelled using nodal representations of constant-mean-curvature surfaces. A case study conducted on etioplast cell membranes in chloroplast precursors establishes the double Diamond surface structure to be dominant in these plant cells. We automate the matching process employing deep-learning methods, which manage to identify structures with excellent accuracy.
While estimated numbers of past and future climate migrants are alarming, the growing empirical evidence suggests that the association between adverse climate-related events and migration is not universally positive. This dissertation seeks to advance our understanding of when and how climate migration emerges by analyzing heterogeneous climatic influences on migration in low- and middle-income countries. To this end, it draws on established economic theories of migration, datasets from physical and social sciences, causal inference techniques and approaches from systematic literature review. In three of its five chapters, I estimate causal effects of processes of climate change on inequality and migration in India and Sub-Saharan Africa. By employing interaction terms and by analyzing sub-samples of data, I explore how these relationships differ for various segments of the population. In the remaining two chapters, I present two systematic literature reviews. First, I undertake a comprehensive meta-regression analysis of the econometric climate migration literature to summarize general climate migration patterns and explain the conflicting findings. Second, motivated by the broad range of approaches in the field, I examine the literature from a methodological perspective to provide best practice guidelines for studying climate migration empirically. Overall, the evidence from this dissertation shows that climatic influences on human migration are highly heterogeneous. Whether adverse climate-related impacts materialize in migration depends on the socio-economic characteristics of the individual households, such as wealth, level of education, agricultural dependence or access to adaptation technologies and insurance. For instance, I show that while adverse climatic shocks are generally associated with an increase in migration in rural India, they reduce migration in the agricultural context of Sub-Saharan Africa, where the average wealth levels are much lower so that households largely cannot afford the upfront costs of moving. I find that unlike local climatic shocks which primarily enhance internal migration to cities and hence accelerate urbanization, shocks transmitted via agricultural producer prices increase migration to neighboring countries, likely due to the simultaneous decrease in real income in nearby urban areas. These findings advance our current understanding by showing when and how economic agents respond to climatic events, thus providing explicit contexts and mechanisms of climate change effects on migration in the future. The resulting collection of findings can guide policy interventions to avoid or mitigate any present and future welfare losses from climate change-related migration choices.
Hans Christian Ørsted gehörte zu den bedeutendsten Physikern seiner Zeit, er und Michael Faraday waren die Schöpfer des Elektromagnetismus. Ein erstes Treffen zwischen Alexander von Humboldt und Oersted fand im Frühjahr 1823 in Paris statt. Weitere Treffen folgten in Altona bzw. Hamburg im Jahr 1827, in Berlin 1828, in Berlin und Potsdam 1843 sowie in Kopenhagen 1845. Die erhaltenen Briefe – zwei Briefe von Humboldt an Ørsted sowie zwei Briefentwürfe von Oersted an Humboldt – gewähren weitere Einblicke in das gute Verhältnis, das diese beiden Wissenschaftler miteinander pflegten. Obwohl Ørsted eines der treuesten Mitglieder des Göttinger Magnetischen Vereins war und beste Beziehungen zu Gauß und Weber unterhielt, spielten im „Kosmos“ Ørsteds Beiträge zum Erdmagnetismus keine Rolle, hier wurden nur Ørsteds Beiträge zum Elektromagnetismus gewürdigt.
During his trip to New Spain in 1803, Alexander von Humboldt visited large tracts of New Spanish territory, which includes modern Mexico and part of the United States. This trip provided the data for his geographical Atlas of the region, as well as information about the ancient Mexican cultures that he would later include in the general Atlas and in other major works, such as Vues des Cordillères. Likewise, Humboldt’s Political Essay on the Kingdom of New Spain displayed a comprehensive physical, natural, economic, and social description of Mexico in the colonial period, which will also be analysed. With these works, Humboldt presented a new geographical and cultural image of New Spain to the European audiences. In addition to this, his work made important contributions to cartographic knowledge.