The Ethiopian Student Movement and the Dilemma of Eritrean Sovereignty

From the perspective of Ethiopian royalists, Pan-Africanists, Marxist internationalists, supports of union, and the broader international community, Eritrean nationalism revealed distressing fissures in many different arguments for preserving Ethiopian territorial unity– arguments not necessarily or explicitly problematic, but nevertheless in opposition to Eritrean demands for the right to national self-determination. For the Ethiopian Student Movement (ESM) specifically, Eritrean sovereignty demanded a reconfiguration of Pan-African unity that conflicted with Ethiopian exceptionalist historiography. Through an analysis of student politics at Haile Selassie University, from 1960-1974, this thesis seeks to complicate existing historiography on the ESM by examining the periodically divergent experiences of Eritrean student activists

Vision-Based Uncertainty-Aware Motion Planning based on Probabilistic Semantic Segmentation

For safe operation, a robot must be able to avoid collisions in uncertain environments. Existing approaches for motion planning under uncertainties often assume parametric obstacle representations and Gaussian uncertainty, which can be inaccurate. While visual perception can deliver a more accurate representation of the environment, its use for safe motion planning is limited by the inherent miscalibration of neural networks and the challenge of obtaining adequate datasets. To address these limitations, we propose to employ ensembles of deep semantic segmentation networks trained with massively augmented datasets to ensure reliable probabilistic occupancy information. To avoid conservatism during motion planning, we directly employ the probabilistic perception in a scenario-based path planning approach. A velocity scheduling scheme is applied to the path to ensure a safe motion despite tracking inaccuracies. We demonstrate the effectiveness of the massive data augmentation in combination with deep ensembles and the proposed scenario-based planning approach in comparisons to state-of-the-art methods and validate our framework in an experiment with a human hand as an obstacle

Evidence for an evolutionary antagonism between Mrr and Type III modification systems

The Mrr protein of Escherichia coli is a laterally acquired Type IV restriction endonuclease with specificity for methylated DNA. While Mrr nuclease activity can be elicited by high-pressure stress in E. coli MG1655, its (over)expression per se does not confer any obvious toxicity. In this study, however, we discovered that Mrr of E. coli MG1655 causes distinct genotoxicity when expressed in Salmonella typhimurium LT2. Genetic screening enabled us to contribute this toxicity entirely to the presence of the endogenous Type III restriction modification system (StyLTI) of S. typhimurium LT2. The StyLTI system consists of the Mod DNA methyltransferase and the Res restriction endonuclease, and we revealed that expression of the LT2 mod gene was sufficient to trigger Mrr activity in E. coli MG1655. Moreover, we could demonstrate that horizontal acquisition of the MG1655 mrr locus can drive the loss of endogenous Mod functionality present in S. typhimurium LT2 and E. coli ED1a, and observed a strong anti-correlation between close homologues of MG1655 mrr and LT2 mod in the genome database. This apparent evolutionary antagonism is further discussed in the light of a possible role for Mrr as defense mechanism against the establishment of epigenetic regulation by foreign DNA methyltransferases

Influence of laterally acquired genetic elements on the physiology of Salmonella enterica

INFLUENCE OF LATERALLY ACQUIRED GENETIC ELEMENTS ON THE PHYSIOLOGY OF SALMONELLA ENTERICA Salmonella spp. are accountable for a large fraction of the global infectious disease burden, with most of their infections being food- or water-borne. As the phenotypic features and adaptive potential of Salmonella spp. appear to be driven mainly by mobile or laterally acquired genetic elements, a better understanding of the behaviour and diversification of these important pathogens consequently requires a more profound insight into the different mechanisms by which these pivotal elements can affect cellular physiology. In this work, research was accordingly focused on the impact of a laterally acquired endonuclease (i.e. Mrr), and a temperate bacteriophage (i.e. P22) on the physiology of Salmonella Typhimurium LT2. Mrr is a cryptic Type IV restriction endonuclease that is characterized by its specificity for modified DNA. The gene encoding Mrr is located in the immigration control region , a foreign genetic element that harbours a large number of restriction systems. In contrast to the Mrr protein of its close relative, Escherichia coli MG1655, we initially found Mrr of LT2 to be inactive. Closer analysis, however, revealed that degeneration of LT2 Mrr might have been enforced by the presence of a laterally acquired Type III methyltransferase in LT2, whose activity in the cell is incompatible with a functional Mrr enzyme. Nevertheless, random mutagenesis revealed that a number of seemingly unrelated mutations could each still render LT2 Mrr constitutively active, indicating its degeneration is readily reversible. P22, on the other hand, is a temperate and Salmonella-specific model phage that over the last 50 years has greatly contributed to our understanding of phage biology and phage host interactions in general. Using a random promoter-trap library, we stumbled upon a novel interaction between P22 and LT2, which is characterized by the deliberate redirection of the host s metabolism. Interestingly, we could identify the actual instigator of this interaction as a small ORFan protein encoded on the P22 genome, but its deletion did not obviously affect infection or lysogenisation by P22. In summary, the research in this work revealed a number of novel mechanisms by which specific mobile or laterally acquired genetic elements can determine or interfere with the behaviour of S. Typhimurium.status: publishe

Analyse der neuen ISGLS-Definition der postoperativen Leberblutung (PHH) – Relevanz und Anwendung in der Klinik

Hintergrund: Um die Qualität von chirurgischen Eingriffen aber auch Ergebnisse klinischer Studien besser vergleichen zu können sind Definitionen von Komplikationen sehr wichtig. Die „international study group on liver surgery“ publizierte unlängst die Definitionen für die postoperative Blutung nach Leberresektionen (posthepatectomy haemorrhage, PHH). Die Komplikation wird je nach Schweregrad in drei Stufen eingeteilt. In der aktuellen Studie soll die Korrelation der Komplikation PHH mit objektiven Parametern wie Krankenhausverweildauer und Mortalität vergleichen werden, um den klinischen Nutzen der Komplikationsdefinitionen besser beurteilen zu können. Patienten und Methoden: Es handelt sich um die retrospektive Auswertung der Leberdatenbank der Chirurgischen Klinik der Universitätsklinik Mannheim im Zeitraum zwischen 2004 und 2014. In diesem Zeitraum erhielten 415 Patienten eine Leberresektion aufgrund unterschiedlicher Lebererkrankungen. Die statische Auswertung erfolgte mittels t-Test und chi-square Test. Ergebnisse: Von den erlittenen Komplikationen lagen bei 29 (7%) postoperative Hämorrhagien (PHH) vor. Davon waren 25 (6.5%) Patienten eine PHH Grad A, drei (0.8%) Patienten eine PHH Grad B und ein (0.4%) Patienten PHH Grad C. Bei den drei Patienten mit PHH Grad B lag die LOS bei (46.67 Tage; SD 57.5 Tage und war somit signifikant verlängert im Vergleich zur Kontrollgruppe ohne PHH, welche (13.39 Tage; SD 8.7 Tage) hospitalisiert waren (p<0.001). Die postoperative Mortalität betrug bei den Patienten mit PHH 17.2% (n=5). Von den 387 Patienten ohne PHH verstarben 14 (3,9%) Patienten während des stationären Aufenthalts. Der Unterschied der Mortalität bei Patienten mit PHH Grad A (10.3%) und PHH Grad B (33.3 %) vs. Patienten ohne PHH (3.9%) ist statistisch signifikant erhöht (p<0.001). Schlussfolgerung: Die neue Definition für das Auftreten einer PHH der ISGLS korreliert mit objektiven Parametern zur Beurteilung des postoperativen Verlaufes. Die neue Definition scheint damit für die Qualitätssicherung und Studien geeignet. Aufgrund ihrer einfachen Anwendbarkeit scheint diese auch für die tägliche Anwendung in der Klinik geeignet zu sein

Evaluation of spatial interpolation methods for annual rainfall on the highlands of Eritrea

No Abstract. Discovery and Innovation Vol. 18(1) 2006: 15-2

Research Assignment TU Delft Contents Table Contents Table..................................................................................................................2

ID No. 103102