Die Jesuitenreduktionen in Paraguay im Lichte der kolonialethischen Diskussion

Leitmotiv der Arbeit ist die Frage nach dem Nächsten, dem Fremden, dem Unbekannten und dessen Wahrnehmung, die gerade in der heutigen Zeit nichts an ihrer Aktualität eingebüßt hat. Der Rahmen ist ein historischer, nämlich die Zeit der „Entgrenzung“ des geographischen Horizonts des Mittelalters und seine insbesondere in Spanien sich unmittelbar stellende Frage nach der Rechtmäßigkeit der Konquista, die sich in der Frage nach dem Nächsten und seinem Menschsein verdichtet. Die Reaktion darauf und die innovative Denkleistung von Vitoria bilden den Ausgangspunkt. Ferner wird auf den Zeitzeugen Las Casas und seinen Kampf für die Indios eingegangen. Dieser gipfelt in dem Disput von Valladolid mit seinem Hauptkontrahenten Sepúlveda. Breiten Raum nimmt das jesuitische Experiment in Paraguay, im speziellen die Guaraníreduktionen ein. Diese bilden die reale historische Grundlage für zahlreiche utopische europäische Projektionen. Es wird versucht, nach einer perspektivenreichen Durchleuchtung des Experiments zu einer abschließenden ethischen Würdigung zu kommen. In den Schlussgedanken wird der Kreis geschlossen und es finden aktuelle gegenwartsbezogene Bezüge statt.The study´s dominant leitmotif concerns the unknown neighbour, i.e. the stranger and how we perceive him, which is an issue much debated these days. The setting is historical, namely the period of a radical dissolution of boundaries and of expansion of Medieval geographical horizons. Closely connected to these phenomena of transition is the question of the legitimacy of the Spanish Conquista, an ethical dilemma which is of great urgency when considering the unknown neighbour as a fellow human being. Immediate responses to this challenging question and Vitoria´s innovative reflections provide the first impetus to the analysis. A further focus is on the contemporary eyewitness Las Casas and his struggles for the cause of the Indios, a conflict which culminates in the dispute of Valladolid with his main opponent, i.e. Sepúlveda. The Jesuit experiment in Paraguay, in particular the so-called Guaraní-reductions, is given expansive attention. These experiments are the historical and really existing origins of numerous European utopian fantasies and projections. It is the aim of the study to investigate the experiment from a plurality of perspectives and thus to reach conclusions which do justice to the ethical issues involved. The final section will close the argumentative circle and will attempt to refer to related current concerns

Reciprocal regulation of PKA and rac signaling

Activated G protein-coupled receptors (GPCRs) and receptor tyrosine kinases relay extracellular signals through spatial and temporal controlled kinase and GTPase entities. These enzymes are coordinated by multifunctional scaffolding proteins for precise intracellular signal processing. The cAMP-dependent protein kinase A (PKA) is the prime example for compartmentalized signal transmission downstream of distinct GPCRs. A-kinase anchoring proteins tether PKA to specific intracellular sites to ensure precision and directionality of PKA phosphorylation events. Here, we show that the Rho-GTPase Rac contains A-kinase anchoring protein properties and forms a dynamic cellular protein complex with PKA. The formation of this transient core complex depends on binary interactions with PKA subunits, cAMP levels and cellular GTP-loading accounting for bidirectional consequences on PKA and Rac downstream signaling. We show that GTP-Rac stabilizes the inactive PKA holoenzyme. However, β-adrenergic receptor-mediated activation of GTP-Rac–bound PKA routes signals to the Raf-Mek-Erk cascade, which is critically implicated in cell proliferation. We describe a further mechanism of how cAMP enhances nuclear Erk1/2 signaling: It emanates from transphosphorylation of p21-activated kinases in their evolutionary conserved kinase-activation loop through GTP-Rac compartmentalized PKA activities. Sole transphosphorylation of p21-activated kinases is not sufficient to activate Erk1/2. It requires complex formation of both kinases with GTP-Rac1 to unleash cAMP-PKA–boosted activation of Raf-Mek-Erk. Consequently GTP-Rac functions as a dual kinase-tuning scaffold that favors the PKA holoenzyme and contributes to potentiate Erk1/2 signaling. Our findings offer additional mechanistic insights how β-adrenergic receptor-controlled PKA activities enhance GTP-Rac–mediated activation of nuclear Erk1/2 signaling

LPMLE3 : a novel 1-D approach to study water flow in streambeds using heat as a tracer

We introduce LPMLE3, a new 1-D approach to quantify vertical water flow components at streambeds using temperature data collected in different depths. LPMLE3 solves the partial differential equation for coupled water flow and heat transport in the frequency domain. Unlike other 1-D approaches it does not assume a semi-infinite halfspace with the location of the lower boundary condition approaching infinity. Instead, it uses local upper and lower boundary conditions. As such, the streambed can be divided into finite subdomains bound at the top and bottom by a temperature-time series. Information from a third temperature sensor within each subdomain is then used for parameter estimation. LPMLE3 applies a low order local polynomial to separate periodic and transient parts (including the noise contributions) of a temperature-time series and calculates the frequency response of each subdomain to a known temperature input at the streambed top. A maximum-likelihood estimator is used to estimate the vertical component of water flow, thermal diffusivity, and their uncertainties for each streambed subdomain and provides information regarding model quality. We tested the method on synthetic temperature data generated with the numerical model STRIVE and demonstrate how the vertical flow component can be quantified for field data collected in a Belgian stream. We show that by using the results in additional analyses, nonvertical flow components could be identified and by making certain assumptions they could be quantified for each subdomain. LPMLE3 performed well on both simulated and field data and can be considered a valuable addition to the existing 1-D methods

A power market-based operation support model for sub-daily hydropower regulation practices

Highlights • Investigate the impact of instant energy demand on sub-daily river regime. • Introducing power market impact index. • Introducing system efficiency ratio index. • Provides an efficient tool for sustainable river management. • Assess the interaction of power market and regulation practices.With increasing power production from renewable energy sources, sub-daily variations in energy demand need to be balanced. Today, hydropower is commonly used as balancing power. In this study, we quantified the impact of capacity constraints, in terms of reservoir volume and hydropower capacity, on the potential to comply with instant energy demand. To evaluate the impact, we developed two new metrics, power market impact and system efficiency ratio, which are based on two threshold flow regimes derived from natural flow as lower threshold release and regulated flow (based on hourly energy prices) as upper threshold release. The operation support model comprises 96 different regulation scenarios based on varying combinations of hydropower and reservoir capacities. For each scenario, an hourly water balance was simulated, to obtain the highest complying with upper threshold release based on actual energy demand. We tested the framework on the Kemijoki river with defined thresholds based on the natural flow regime (tributary river Ounasjoki) and the hourly energy price in Finland in 2017, and estimated the impact of regulation on hourly flow regime at the Taivalkoski hydropower station. The annual flow regime impact in 2013, 2014 and 2015 was estimated to be 74%, 84% and 61%, respectively, while the monthly impact varied from 27% to 100%. Our framework for evaluating interactions between the power market and sub-daily regulation practices is a useful novel tool for sustainable river management and can be easily applied to different rivers and regions and evaluated for different timescales

Leitplanken gegen Studiengebühren und Bremer Finanzausgleichs-Tricksereien

Methylated cytosines in total poly(A) ESC RNA. (XLSX 761 kb

NALP3 inflammasome upregulation and CASP1 cleavage of the glucocorticoid receptor cause glucocorticoid resistance in leukemia cells

Glucocorticoids are universally used in the treatment of acute lymphoblastic leukemia (ALL), and resistance to glucocorticoids in leukemia cells confers poor prognosis. To elucidate mechanisms of glucocorticoid resistance, we determined the prednisolone sensitivity of primary leukemia cells from 444 patients newly diagnosed with ALL and found significantly higher expression of CASP1 (encoding caspase 1) and its activator NLRP3 in glucocorticoid-resistant leukemia cells, resulting from significantly lower somatic methylation of the CASP1 and NLRP3 promoters. Overexpression of CASP1 resulted in cleavage of the glucocorticoid receptor, diminished the glucocorticoid-induced transcriptional response and increased glucocorticoid resistance. Knockdown or inhibition of CASP1 significantly increased glucocorticoid receptor levels and mitigated glucocorticoid resistance in CASP1-overexpressing ALL. Our findings establish a new mechanism by which the NLRP3-CASP1 inflammasome modulates cellular levels of the glucocorticoid receptor and diminishes cell sensitivity to glucocorticoids. The broad impact on the glucocorticoid transcriptional response suggests that this mechanism could also modify glucocorticoid effects in other diseases

Is the Hyporheic Zone Relevant beyond the Scientific Community?

Rivers are important ecosystems under continuous anthropogenic stresses. The hyporheic zone is a ubiquitous, reactive interface between the main channel and its surrounding sediments along the river network. We elaborate on the main physical, biological, and biogeochemical drivers and processes within the hyporheic zone that have been studied by multiple scientific disciplines for almost half a century. These previous efforts have shown that the hyporheic zone is a modulator for most metabolic stream processes and serves as a refuge and habitat for a diverse range of aquatic organisms. It also exerts a major control on river water quality by increasing the contact time with reactive environments, which in turn results in retention and transformation of nutrients, trace organic compounds, fine suspended particles, and microplastics, among others. The paper showcases the critical importance of hyporheic zones, both from a scientific and an applied perspective, and their role in ecosystem services to answer the question of the manuscript title. It identifies major research gaps in our understanding of hyporheic processes. In conclusion, we highlight the potential of hyporheic restoration to efficiently manage and reactivate ecosystem functions and services in river corridors

Syntheses of modified nucleic acids towards characterization and sequencing of modified RNA

Modifizierte synthetische RNA Oligonukleotide sind essentielle Werkzeuge für die strukturelle und funktionelle Untersuchung und die Entwicklung von neuen Sequenziermethoden modifizierter Nukleinsäuren. Diese Arbeit beleuchtet die Anwendung von RNAFestphasensynthese für den Einbau von modifizierten Nukleobasen in RNA um epigenetische Cytosin Modifikationen zu untersuchen und die RNA Sequenzierung in Kombination mit metabolischer Markierung zu erleichtern. Während die Rollen von epigenetischen Cytosin Modifikationen in DNA schon genau untersucht wurden, sind die Funktionen von 5-Methylcytosin (m5C), 5-Hydroxymethylcytosin (hm5C), 5-Formylcytosin (f5C) und 5-Carboxylcytosin (ca5C) in RNA noch weigehend unbekannt. Im ersten Teil dieser Arbeit wird ein effizienter Zugang zu hm5C, f5C und ca5C Phosphoramiditen, ausgehend von kommerziell erhältlichem Cytidin und der Einbau dieser Modifikationen in RNA Oligonukleotide, präsentiert. Schmelzkurven-Analyse und Kristallisation von hm5C beinhaltenden RNA Oligonukleotiden haben ergeben, dass, im Vergleich zu unmodifizierter RNA, die 5-Hydroxymethyl Gruppe nur einen kleinen Einfluss auf die thermische Stabilität und die Struktur von RNA Duplexen zeigt. Es wurde jedoch eine leichte Öffnung des hm5C-G Basenpaares in der Kristallstruktur der E.coli 23S rRNA Sarcin-Ricin Schleife beobachtet und es wurde gezeigt, dass die hm5C Modifikation eine Störung der hohen thermischen Stabilität der UGCG Schleife mit sich bringt, wenn ein C mit einem hm5C ersetzt wird. Bisulfit Sequenzierung ist eine gängige Anwendung, um m5C Modifikationen in DNA mit einer Ein-Basen Auflösung zu detektieren. Diese Methode basiert auf der Umwandlung von Cytosin in Uracil bei der Behandlung mit Bisulfit und wurde kürzlich für RNA adaptiert. In dieser Arbeit wurde das Verhalten der oxidativen m5C-Derivate hm5C, f5C und ca5C während der Bisulfit- Umwandlung in RNA Oligonukleotiden untersucht. Während die Diskriminierung zwischen C und m5C während der Bisulfit-Umwandlung unabhängig von Sekundärstruktur Elementen bestätigt wurde, zeigte hm5C eine Umwandlung zu Cytosin-5-methylensulfonat (CMS), und sowohl f5C als auch ca5C wurden zu Uracil transformiert. Zusätzlich wurden 5-Biotin markierte RNA Oligonukleotide mit m5C und hm5C Modifikationen synthetisiert, die für Protein-Bindungs-Immunopräzipitations Verfahren verwendet werden. Massenspektrometrische Analysen mittels Kollisionsanregung zeigten eine Präferenz von f5C zu erhöhtem Basenverlust im Vergleich zu hm5C und C. Im zweiten Teil dieser Arbeit wurden 4-Thiouridin-(s4U)-modifizerte RNA Oligonukleotide verwendet, um Sequenzierungstechniken in Verbindung mit s4U metabolischer Markierung zu verbessern. Während die in vivo Markierung von wachsenden RNAs mit s4U schon vielfach verwendet wurde, um RNA Dynamik zu untersuchen, wird beim herkömmlichen Ansatz dieser Methode eine Affinitäts-Reinigung der s4U-markierten RNA benötigt, die im Normalfall durch Anbringen von Biotin mittels Disulfid-Reagenzien bewerkstelligt wird. Hier stellen wir eine alternative Reaktion für die selektive Anbindung von Biotin an RNA vor. Nach der Funktionalisierung mit (4-azidobut-1-ynyl)-1,2-benziodoxol-3(1H)-on (ABBX) wird mittels „Click Chemie“ die Biotin Markierung angebracht. Wenngleich diese Reaktion prinzipiell anwendbar ist, wird die Effektivität dieser Methode durch die niedrige Ausbeute der ABBX Addition (< 50%) eingeschränkt. Bei einem alternativen Zugang erwies sich die direkte Transformation von s4U-zu-C mit Osmiumtetroxid in Ammoniumchlorid Puffer als sehr effizient. Die Anwendbarkeit dieser Umwandlung wurde an synthetischen RNA Oligonukleotiden, E.coli tRNAVal und mRNA von HEK Zellen gezeigt. Diese Reaktion machte es möglich, den arbeitsintensiven und fehleranfälligen Prozess der Affinitätsreinigung von s4U markierter RNA zu umgehen, der vor der Sequenzierung nötig war. In einem einfachen und direkten methodischen Prozess, wurden s4U-markierte RNA Transkripte behandelt, revers transkribiert, vervielfältigt und sequenziert, um die Dynamik in der Entstehung von neuen Transkripten zu untersuchen.Modified synthetic RNA oligonucleotides are essential probes for structural and functional investigations and for the development of new sequencing methods of modified nucleic acids. This work highlights the application of solid-phase RNA synthesis to incorporate modified nucleobases into RNA in order to study epigenetic cytosine modifications and to facilitate RNA sequencing in combination with metabolic labeling. While the roles of epigenetic cytosine modifications in DNA have already been elucidated in detail, the functions of 5-methylcytosine (m5C), 5-hydroxymethylcytosine (hm5C), 5-formylcytosine (f5C) and 5-carboxylcytosine (ca5C) in RNA remain elusive. In the first part of this study, efficient synthetic access to hm5C, f5C and ca5C phosphoramidites from commercially available cytidine and the incorporation of these modifications into RNA oligonucleotides is presented. Thermal denaturation experiments and crystallization of hm5C containing RNA oligonucleotides revealed, that the 5-hydroxymethyl moiety shows only minor influence on thermal stability and structure of RNA duplexes, compared to the unmodified counterparts. However, a slightly opened base pair of hm5C-G was observed within the crystal structure of the E.coli 23S rRNA sarcin-ricin loop and the hm5C moiety was shown to perturb the extra high stability of the UGCG loop upon replacement of C by hm5C. Bisulfite sequencing has been used extensively to detect m5C modifications in DNA with single base-resolution. This procedure relies on the conversion of cytosine to uracil upon treatment with bisulfite and has recently been adapted for RNA. In this work, the behavior of the m5C oxidative derivatives hm5C, f5C and ca5C during bisulfite conversion was studied on RNA oligonucleotides. While the discrimination of C and m5C during bisulfite conversion was verified to be independent from secondary structure, hm5C showed a conversion to cytosine-5-methylenesulfonate (CMS) and both f5C and ca5C were transformed into uracil. Additionally, 5-biotin labeled RNA oligonucleotides carrying m5C and hm5C for protein pulldown experiments were synthesized and collisionally activated dissociation in mass spectrometric analysis showed the preference of f5C to form abasic sites compared to hm5C and C. In the second part of this thesis, 4-thiouridine-(s4U)-modified RNA oligonucleotides were utilized to improve sequencing techniques in combination with s4U metabolic labeling. While in vivo s4U labeling of nascent RNAs has been widely used to study RNA dynamics before, the standard approach required an affinity purification of s4U-labeled RNA, which was usually performed by attachment of a biotin moiety with disulfide reagents. Herein an alternate reaction for this biotinylation is provided by selective functionalization of s4U in RNA with (4-azidobut-1-ynyl)-1,2-benziodoxol-3(1H)-one (ABBX) and subsequent attachment of the biotin moiety by strain-promoted alkyne azide cycloaddition (“click chemistry”). Although generally viable, the addition of ABBX to s4U is not entirely satisfying due to its limited efficiency (< 50%). In an alternative approach, the direct transformation of s4U-to-C in RNA with osmium tetroxide in ammonium chloride buffer proved to be very efficient. The applicability of this conversion was demonstrated on synthetic RNA oligonucleotides, E.coli tRNAVal and mRNA from HEK cells. This reaction made it possible to circumvent the laborious affinity purification of s4U metabolically labeled RNA, which was required prior to high-throughput sequencing. In a simple and straight-forward procedure, s4U pulse-labeled RNA transcripts were converted, reverse-transcribed, amplified and sequenced in order to study the generation of new transcripts.vorgelegt von Mag. rer. nat. Christian RimlKumulative Dissertation aus drei ArtikelnZusammenfassung in deutscher SpracheUniversität Innsbruck, Dissertation, 2017OeBB(VLID)226169