Impacts of ocean acidification and warming on Arctic calcifying key species : benthic coralline red alga (Lithothamnion glaciale) and pelagic thecosome pteropods (Limacina helicina & L. retroversa) = Auswirkung von Ozeanversauerung und Ozeanerwärmung auf die Biologie arktischer kalzifizierender Schlüsselarten: Benthische koralline Rotalge (Lithothamnion glaciale) und pelagische thekosmome Flügelschnecken (Limacina helicina & L. retroversa)

Over the last two centuries human activities significantly changed the Earth system. Atmospheric CO2 concentrations were increased by ~25% in only 50 years (1965 to 2015) through combustion of fossil fuels and changes in land use. Consequences of these activities are a warming climate and the ‘acidification’ of the world oceans. A doubling of surface ocean carbon dioxide- (CO2) and proton- (H+) and a 40% decrease of the carbonate ion (CO32-) concentrations until the end of this century will probably affect many marine organisms. Due to low temperatures, the Arctic Surface Ocean will be one of the first to experience mean annual corrosive conditions for calcified organisms. This makes the Arctic Ocean a bellwether for global impacts of ocean acidification (OA) on marine life. Biogenic calcium carbonate often establishes ecological functions like being the fundament for species rich habitats in the case of hermatypic corals and crustose coralline algae (CCA) or impacting global carbon cycling embodied by coccolithophores, foraminifera and thecosome pteropods. The marine carbon cycle influences the destination of human CO2 emissions and the development of the global climate. Therefore, the ecological importance of CCA and pteropods, their involvement in the marine carbon cycle and their anticipated vulnerability to OA call for research on their fate in the future ocean. This doctoral thesis investigates the effects of warming and ocean acidification on growth, calcification, dissolution, corrosion and survival of Arctic calcifying keystone species Lithothamnion glaciale (CCA) and Limacina helicina and retroversa (thecosome pteropods)

The geopolitics of real estate: assembling soft power via property markets

The article problematizes the role of real estate in geopolitical circulations. The internationalization of real estate increases mutual dependencies and vulnerabilities between nation states and therefore calls for a better appreciation of the geopolitical externalities and exteriorities of real estate. The article brings together disjoint bodies of literature on real estate globalization, assemblage theory, and international relations to show how real estate is a case of the geopolitics of the multiple – geopolitics that is being assembled by diverse and distributed actors, discourses, and materialities representing the contingent and emergent formation of connections and considerations, which affect the ways how foreign relations are negotiated today. The argument is substantiated by considering several dimensions of the real estate/geopolitics nexus: (i) external influences over domestic real estate markets; (ii) the implications of outward real estate investment; (iii) state-led mega-projects conveying externally the power of the state. These dimensions are considered empirically in the context of the renewed geopolitical tensions between a resurgent Russia and the West. Overall, the article calls for a better positioning of real estate in the conceptualizations of soft power, state power, and geopolitics

Statecraft strategies and housing financialization at the periphery: Post-socialist trajectories in Russia and Poland

A new literature on housing and financialization has emerged in recent years, but scholars have yet to examine how political actors shape national trajectories of housing financialization. In this article, we address this shortcoming by examining the cases of Russia and Poland in the 1990-2018 period. We argue that in both contexts political elites implemented a radical market-oriented reshaping of housing finance. However, by pursuing distinct statecraft strategies and modes of integrating the domestic economy into global markets, Russian and Polish political elites created two divergent trajectories of housing financialization. Russian political elites pursued patrimonial statecraft strategies and a mode of global economic integration based on raw material exports. The Putin administration channeled revenues from raw material exports into the securitization-based housing finance system and used this infrastructure as an instrument of hegemonic power. In doing so, the Russian government shielded homeowners from exposure to financial risk. In contrast, Polish political elites pursued liberal statecraft strategies and a mode of global economic integration based on foreign capital inflows. Polish political parties therefore enabled foreign banks to dominate the housing finance system and sell foreign currency mortgages, which exposed homeowners to considerable financial risk. In light of these findings we call for further research into the political factors that shape the process of housing financialization, both in the post-socialist space and beyond

Towards a Creative Virtual Environment for Design Thinking

Background: Digital transformation changes collaboration processes, particularly in rapidly digitalizing countries like ASEAN states. Co-creation and innovation processes become increasingly flexible and time and location independent. But virtual collaboration faces context-specific challenges like technical problems, lack of social presence, and ambiguous attitudes towards autonomy and accountability. Therefore, this study addresses two research questions to contribute to designing a creative virtual environment: First, which Design Principles (DPs) should be prioritized in designing a user-centered creative virtual environment? Second, which Design Features (DFs) effectively implement the DPs in creative virtual collaboration from a user perspective? Method: A user-centered Design Science Research approach was chosen to identify, implement and evaluate DPs and DFs. DPs were derived from theories on creativity drivers in five areas: functionality, process, mood, meaning, and collaboration. The DPs were implemented in a virtual design thinking workshop at a German international university. A qualitative thematic analysis evaluated user feedback from 38 international students from Asia, Africa, America, and Europe. Results: Insights from user feedback indicate that seven DPs should be prioritized and effectively implemented in a virtual environment for creative collaboration: (1) Provide rich, appropriate resources to inspire creative thinking; (2) Technical problems and connectivity issues must be anticipated and mitigated; (3) The environment must foster social presence and interaction, and (4) effective communication and visualization; (5) Methods and technologies must be adapted to the creative process and individual needs; (6) The group work benefits from structured but flexible tasks and time management support; (7) Provide space for individual work that allows autonomy and solitary contemplation. Conclusion: A tailored setup that adapts to context-specific challenges distinct from the on-site collaboration is necessary to facilitate creative virtual collaboration. The study results apply and expand current theories on technology utilization and inform the practical design of a virtual environment for creative collaboration

Impact of ocean acidification and elevated temperatures on early juveniles of the polar shelled pteropod Limacina helicina: mortality, shell degradation, and shell growth

Due to their aragonitic shell thecosome pteropods may be particularly vulnerable to ocean acidification driven by anthropogenic CO2 emissions. This applies specifically to species inhabiting Arctic surface waters that are projected to become locally undersaturated with respect to aragonite as early as 2016. This study investigated the effects of rising pCO2 partial pressures and elevated temperature on pre-winter juveniles of the polar pteropod Limacina helicina. After a 29 days experiment in September/October 2009 at three different temperatures and under pCO2 scenarios projected for this century, mortality, shell degradation, shell diameter and shell increment were investigated. Temperature and pCO2 had a significant effect on mortality, but temperature was the overriding factor. Shell diameter, shell increment and shell degradation were significantly impacted by pCO2 but not by temperature. Mortality was 46% higher at 8 °C compared to 3 °C (in situ), and 14% higher at 1100 μatm CO2 as compared to 230 μatm CO2. Shell diameter and increment were reduced by 10% and 12% at 1100 μatm CO2 as compared to 230 μatm CO2, respectively, and shell degradation was 41% higher at elevated compared to ambient pCO2 partial pressures. We conclude that pre-winter juveniles will be negatively affected by both rising temperature and pCO2 which may result in a possible abundance decline of the overwintering population, the basis for next year's reproduction

Die Elektrizitäts- und Gaswirtschaft im Spannungsfeld zwischen Wettbewerb und staatlicher Lenkung

Die Entflechtung der Netze von den liberalisierten Bereichen der Energieversorgungsunternehmen (EVU) spiegelt sich in der Staatsaufsicht wider: Die liberalisierten Tätigkeitsbereiche werden dem freien Spiel der Kräfte ausgesetzt und unterliegen im Falle von Marktmacht der kartellrechtlichen Missbrauchsaufsicht. Demgegenüber wird der Netzbetrieb vollumfänglich und ausschließlich durch die Regulierungsbehörden überwacht. Trotz wesentlicher Unterschiede haben beide Formen der Staatsaufsicht die Funktion, unternehmerisches Handeln derart zu lenken, dass ein effektiver Wettbewerb im Energiemarkt möglich ist. Mit dem Ziel der Wettbewerbsförderung wird das Energierecht ständig Reformplänen unterzogen, ohne dass der Verordnungsgeber bereits bestehenden Konkretisierungsaufträgen umfassend nachkommen konnte. Unter Berücksichtigung der ausstehenden Rechtsverordnungen müssen Reformen ein angemessenes Verhältnis von staatlicher Steuerung und unternehmerischer Freiheit beachten.Government supervision reflects the ongoing segregation of the distribution networks from the liberalised sectors of the power supply industry: The latter are exposed to full competition and are subject to the control of abusive practices by competition authorities. The networks, however, are controlled fully and exclusively by regulatory authorities. Despite their substantial differences, both forms of supervision are aimed at directing business activities to ensure effective competition on the energy markets. To promote competition, energy law is undergoing constant reform, but the required ordinances are yet to be enacted. New reform ideas should consider the outstanding ordinances and maintain an appropriate balance between government supervision and corporate freedom

Exploring the Perceived Relevance of University Mathematics Studies by First-Semester Teaching Students

As earlier research results suggest that many mathematics teaching students criticize a missing relevance in their studies, we explore explanations and interrelationships of their relevance assessments. We aim at finding out how one could support the students in attributing relevance to their study programs. A two-fold model for relevance assessments in mathematics teacher education is proposed, consisting of relevance content and relevance reasons. We investigate students' relevance perceptions of mathematical topics and of topics’ complexities, as well as their rating of individual and societal/ vocational relevance reasons, all in relation to their perception of the relevance of their overall program of study. Contrary to earlier research findings, our results suggest that mathematics teaching students already do attribute relevance to many content areas and that a preparation for the teaching profession is not the only reason for them to assign relevance. There also seem to be many students who would attribute relevance if they could develop as individuals and pursue their interests. We suggest that giving students opportunities to set individual priorities in their studies could hence support their relevance assessments. As low relevance assessments seem to be connected to students’ motivational problems, students might profit from motivational support, as well

Statecraft strategies and housing financialization at the periphery: Post-socialist trajectories in Russia and Poland

A new literature on housing and financialization has emerged in recent years, but scholars have yet to examine how political actors shape national trajectories of housing financialization. In this article, we address this shortcoming by examining the cases of Russia and Poland in the 1990-2018 period. We argue that in both contexts political elites implemented a radical market-oriented reshaping of housing finance. However, by pursuing distinct statecraft strategies and modes of integrating the domestic economy into global markets, Russian and Polish political elites created two divergent trajectories of housing financialization. Russian political elites pursued patrimonial statecraft strategies and a mode of global economic integration based on raw material exports. The Putin administration channeled revenues from raw material exports into the securitization-based housing finance system and used this infrastructure as an instrument of hegemonic power. In doing so, the Russian government shielded homeowners from exposure to financial risk. In contrast, Polish political elites pursued liberal statecraft strategies and a mode of global economic integration based on foreign capital inflows. Polish political parties therefore enabled foreign banks to dominate the housing finance system and sell foreign currency mortgages, which exposed homeowners to considerable financial risk. In light of these findings we call for further research into the political factors that shape the process of housing financialization, both in the post-socialist space and beyond