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Digital unterstützte universitäre Anfangslehre in der Informatik unter Berücksichtigung heterogener Gruppen
Get PDFProgrammierenlernen stellt eine hohe kognitive Belastung dar. Aufgrund unterschiedlicher Vorkenntnisse und Motivation, abhängig vom Studienziel, liegt insbesondere in der studiengangsübergreifenden Anfangslehre der Informatik eine hohe Heterogenität bei den Studierenden vor. Der vorliegende Mantelbeitrag zur kumulativen Dissertation bettet Forschungsbeiträge ein, die den Gesamtkontext und ausgewählte Aspekte der Herausforderungen der Lehre in diesem Bereich untersuchen. Dabei werden die Möglichkeiten und Vorteile digitaler Werkzeuge in der Lehre berücksichtigt.
Im Zentrum der Arbeit steht dabei ein iterativ über mehrere Jahre gestaltetes und evaluiertes Modulkonzept für ein studiengangsübergreifendes Einführungsmodul in der Informatik. Als Basis diente dabei das Konzept des Flipped Classrooms. Bei diesem wird die Inhaltsvermittlung mit geeignetem Material auf Selbstlernphasen ausgelagert, während Aktivitäten zur Anwendung und Übung in synchronen Veranstaltungen stattfinden, um die Vorteile gemeinsamer Arbeit und direkter Hilfestellung zu nutzen. Unterstützt durch Aspekte der Projektarbeit, Gamification und wachsenden Abgabezeiträumen für verpflichtende Aufgaben entstand dabei ein Konzept, das sich für Lernende mit unterschiedlichen Graden an Vorwissen und diversen Studienfächern zu eignen scheint, wie die Evaluationsergebnisse auf Ebene der Studierenden und Tutoren zeigen. Eine Studie zu fünf verschiedenen Arten digitaler Lernmaterialien, die sich in Perfektionismusanspruch sowie in der Art als Live Coding oder Worked Example unterscheiden, ergänzt die praxisbezogene Forschung. Dabei konnten keine signifikanten Unterschiede bezüglich der Lerntransferleistung der Teilnehmenden mit verschiedenen Lernmaterialien festgestellt werden. Aus der Befragung geht hervor, dass Studierende Kombinationen verschiedener Arten bevorzugen und Fehler auch als Lerngelegenheiten auffassen können.
Zur genaueren Erforschung der Heterogenität unter den Studierenden des Moduls wurden zwei Studien durchgeführt. Eine qualitative Untersuchung beschäftigt sich mit den Einstellungen und Erwartungen zum Modul zu dessen Beginn. Durch Interviews mit ausgewählten Studierenden konnte dabei festgestellt werden, dass der Vorkurs und die ersten Vorlesungen, aber auch der Studiengang und Vorkenntnisse einen Einfluss auf die Vorstellungen der Teilnehmenden haben. Studierende thematisch entfernterer Studiengänge ohne Vorkenntnisse erwarteten teilweise Inhalte, die nicht zur Informatik gehören. Eine weitere Studie beschäftigt sich quantitativ mit der Bedeutung des Begriffs der Frustrationstoleranz für das Studium der Informatik in der Anfangsphase. Dabei wurden die Daten für einen psychologischen Fragebogen zur Frustrationstoleranz sowie eine Selbsteinschätzung am Anfang und am Ende des Kurses erfasst und analysiert. Dabei zeigte sich, dass die erfasste Frustrationstoleranz sich durch den Informatikkurs nicht signifikant änderte. Die Verwendung des Begriffs der Frustrationstoleranz als Voraussetzung oder Ziel eines Informatikstudiums sollte daher überdacht werden.
Insgesamt beschreibt die Arbeit Untersuchungen auf unterschiedlichen Ebenen eines Einführungsmoduls der Informatik mit heterogenen Teilnehmenden hinsichtlich der Vorkenntnisse und Motivation. Es werden Ansätze dargelegt mit den erfassten unterschiedlichen Bedürfnissen umzugehen, Materialien lernförderlich zu gestalten und zeitgemäße Lehrkonzepte, die Möglichkeiten der Digitalisierung gewinnbringend nutzen, zu entwickeln
What is the current state of research concerning self-efficacy in exercise behaviour? Protocol for two systematic evidence maps
No full textIntroduction Knowing about a risk factor is not sufficient to ensure corresponding behaviour as additional psychological factors play a role. Self-efficacy is one of the major factors. This also applies to physical activity and exercise behaviour, which is a major public health topic in both primary and secondary prevention. The amount of research on self-efficacy in exercise behaviour is high yet remains uncharted. This protocol presents the research design for two systematic evidence maps on self-efficacy in exercise behaviour in (1) primary prevention and (2) secondary prevention. These maps will thus provide a comprehensive overview over the current state in published empirical research as a starting point for future researchers.
Methods and analysis The databases Medline (via PubMed) and PsycINFO (via EbscoHost) will be searched using the search terms ‘self-efficacy’ and any of the search terms ‘sport’ and ‘exercise’ in titles and abstracts. All empirical research studies which have measured self-efficacy in relation to exercise behaviour will be included. The primary prevention systematic evidence map will aggregate all studies on healthy humans and the secondary prevention systematic evidence map will include all studies on humans with a pre-existing condition. We will extract and present the data points authors, title, year, sample size (N), age groups, surveyed sport and method of measuring self-efficacy in both systematic evidence maps. Moreover, we will extract and present the target group in the systematic evidence map on primary prevention and the pre-existing condition in the systematic evidence map on secondary prevention. In addition to a data table, we will create freely accessible evidence maps in the form of graphs
Tracking wintering areas and post-breeding migration of a declining farmland bird – An indispensable basis for successful conservation
Get PDFMany farmland birds, such as the Eurasian Curlew (Numenius arquata; here in after Curlew), are in steep decline. So far, decreased reproduction and, hence, an insufficient number of offspring to compensate for adult mortality has been considered the main driver of the recent population collapse. However, despite extensive conservation measures in most breeding areas, there are no signs of a general reversal of the population trend. Accordingly, conservation has to focus on decreasing adult mortality outside the breeding areas as well. For Curlews breeding in NW Germany, ring recoveries suggest that the main wintering areas are the coastlines of western France and southern England. However, such data are often biased in space and time. Here, we used GPS tracking to investigate the wintering areas and post-breeding migration of Curlews of the main German breeding population based on large sample size. Altogether, we tagged 86 adult breeding birds at 23 subareas across a transect of about 250 km (in length) in NW Germany. Curlews started post-breeding migration right after finishing breeding or attempting to breed, which was mainly in mid-June. We identified the coastlines of Great Britain/Ireland, western France and the Netherlands, in particular the Rhine-Meuse-Delta and the Wadden Sea, as the main wintering areas of Curlews breeding in NW Germany. We found a latitudinal structuration of migration, with birds nesting further north using more northerly wintering areas. However, in some cases, wintering areas of birds of the same subpopulation were located more than a thousand kilometres apart from each other. All three main stopover areas identified by our study (German/Dutch Wadden Sea, Dutch Rhine-Meuse-Delta, French Normandy) overlap in large parts with the main wintering areas. Since Curlews spend most of the year outside their breeding areas, and wintering and stopover areas also suffer from rapid environmental change, conservation has to additionally focus on these areas. Nearly one third (29%) of the tracked birds wintered in France or used French stopover areas. Accordingly, they might potentially be affected by a resumption of hunting, which is currently in discussion in France. Our study provides an important basis for the protection of wintering and stopover areas of the main German breeding population but also for other wader species migrating along the East Atlantic Flyway
Soil security in floodplain and river restoration projects
No full textFloodplains and their soils provide a vast range of ecosystem services for nature and humans. At the same time, however, these ecosystems are among the most degraded in the world. During the past decades an increased effort has been made towards the restoration of floodplains and rivers; however, in such projects, soil is often overlooked. To assess the actual status in Germany an online survey has been conducted to investigate the obstacles to soil protection from the restorer's view, and to find ways to better integrate soil protection in such projects. The results show that soil is already present in project planning and implementation, but a special focus is set on pollution. Not all aspects of the soil are equally considered, usually because of financial constraints. Besides the financial aspect, other obstacles include complicated regulations on soil protection in Germany and a lack of soil awareness. There are efficient tools to avoid harmful soil changes on construction sites like the Pedological Construction Supervision (PCS), however, this is often seen as an additional financial and organizational burden. To better integrate soil in restoration projects, a special interest lies on the connectivity component of the Soil Security concept that aims to increase soil awareness of all stakeholders. This is accompanied by planned new soil legislation on soil protection in Germany
People of Color
Get PDFPeople of Color (PoC) ist ein politischer Bündnisbegriff zur Selbstbezeichnung von Menschen, die rassistische Erfahrungen im Alltag machen. Obschon die Bezeichnung PoC seit den 1990er Jahren in Deutschland zunehmend verwendet wird – mittlerweile auch erweitert als BPoC für Black and People of Color –, gab es auch davor schon Begriffe, mit denen migrantisierte Menschen sich selbst bezeichneten und so gegen rassistische Fremdzuschreibungen zur Wehr setzten. Als besondere Formen der Selbstbezeichnung werden die Begriffsgeschichten von Afro-Deutsche/Schwarze Deutsche, Kanak/Kanake und Asiatische Deutsche kurz vorgestellt. Um die Relevanz dieser Begriffe für eine selbstbestimmte und widerständige Praxis der Selbstbezeichnung herauszuarbeiten, geht der Beitrag zudem darauf ein, welche gesellschaftlichen Prozesse als Rassismus und Rassifizierung gefasst werden – und wie diese mit Prozessen der Veranderung durch Migration verschränkt sind
Collective action and individual adaptation in natural resource management under the threat of ecosystem change: Insights from economic experiments
Get PDFScientific evidence shows that climate change increases the frequency of climate extremes across the globe. These climate extremes exogenously pressure local resource users by causing destruction of natural resources, often affecting ecosystems that already have deteriorated due to overexploitation in the past. The future state of natural resources and entire ecosystems is thereby determined by both exogenous (climate) and endogenous (management by resource users) dynamics. The combination of both the uncertain changing environmental conditions and manmade overexploitation will make the sustainable management of natural resources by local resource users more challenging in the future.
Depending on the underlying ecosystem dynamics, the combination of overexploitation and climate extremes may cause sudden abrupt shifts in natural resources if a resource is driven to its critical threshold (tipping point). These shifts are termed regime shifts. In its most drastic form, a regime shift results in the collapse of the resource with severe economic consequences. Ecological and meteorological warning and forecast systems could potentially warn of approaching regime shifts and climate extremes, thereby motivating the resource users for more sustainable resource management and investments in protective adaptation.
Self-governance of natural resources highly depends on collective action. Resource users need to cooperate and coordinate their resource extraction strategies to keep a resource at a sustainable level of regrowth and to prevent it reaching a critical threshold. Policy makers and ecologists must decide when and how to inform local resource users about the potential threat of crossing critical thresholds. However, critical thresholds are often unknown and ecological early warning signals only provide uncertain threshold knowledge. Knowing if the communication of early imprecise threshold information bears a risk to hamper collective action is thus critical. In addition, in some cases, individual adaptation behaviour determines how far an individual experiences economic losses due to climate extremes. In these cases, the issue is not about collective action, but rather about individuals’ responsiveness to early warnings.
To further understand human behaviour in the light of the aforementioned ecological dynamics, three economic experiments were designed and implemented. The results of these experiments are presented in the three academic papers of this thesis (Chapter 2 to 4):
The first paper, titled “The interaction of shock experience and threshold knowledge in natural resource management”, was co-authored by myself with Aneeque Javaid and Stefanie Engel (Chapter 2). This paper addresses the lack of evidence in the literature on the impact of the interaction of exogenously and endogenously driven change in ecosystems on collective action. To analyse this interaction and find the main driver of change in groups’ resource extraction strategies, a novel, (quasi-) continuous-time common-pool resource (CPR) experiment was designed and implemented in the laboratory. The CPR experiment incorporates both dynamics: an unexpected exogenous shock that causes resource scarcity and a critical threshold, at which the resource collapses. The impact of initial resource scarcity on groups’ extraction behaviour is compared to the impact of shock driven scarcity. Furthermore, the effect of shock experience on extraction strategies in the future is assessed. The results indicate that while group members cooperate less when experiencing an exogenous shock to their resource, the knowledge of a critical threshold still motivates successful coordination. However, cooperation amongst group members and efficiency of resource extraction is more sensitive to the resource scarcity itself, than the experience of an exogenous shock. There is no significant effect of shock experience on group’s future extraction strategies.
The second paper, “Are imprecise early warnings a potential benefit or threat to sustainable resource management?”, was co-authored by myself with Tobias Vorlaufer and Stefanie Engel (Chapter 3). This paper asks whether an imprecise early threshold warning alters cooperation amongst resource users and analyses if there is a danger of deteriorating individuals’ responses to the certain threshold knowledge by giving an imprecise early warning. On the one hand, imprecise early warnings could raise awareness about the resource’s dynamics and thus, encourage collective action. On the other hand, imprecise early warnings could be taken as a sign of an inevitable upcoming loss of the resource. Thus, resource users increase their individual extraction efforts and collective action fails. To assess the effect of imprecise early warnings on collective action, two additional treatments for the CPR experiment were designed and implemented. The two treatments differ in the degree of uncertainty about the threshold level in the beginning. While groups in both treatments know of the critical threshold, only one treatment receives an imprecise early threshold warning in form of a known threshold range. The experimental results show no effect of such an imprecise early warning on cooperation and coordination amongst group members in comparison to groups who only know of the mere threshold existence.
The third paper, “False and missed alarms in seasonal forecasts affect individual adaptation choices”, was again co-authored by myself with Tobias Vorlaufer and Stefanie Engel
(Chapter 4). It analyses the effect of varying forecast accuracy on individuals’ responsiveness to climate forecast systems. Climate extremes can result in economic losses if individuals are not adequately prepared. The effect of climate forecast systems however, likely depends on their accuracy and individuals’ responsiveness to inaccurate climate warnings. An online experiment was designed and implemented to assess individuals’ responsiveness to climate forecasts that issue potentially inaccurate warnings about approaching climate extremes leading to the experience of false and/or missed alarms. The results of this experiment indicate that experiencing false alarms more frequently leads to a decrease in individuals’ adaptation investments in response to future warnings (so called “cry-wolf-effect”), but has no impact on individuals’ responsiveness to the forecast if no warning is issued. In contrast, experiencing missed alarms more frequently leads to an increase in individuals’ responsiveness and investment in adaptation regardless whether or not a warning is issued by future forecasts. Individuals who experienced missed alarms more frequently react more sensitive on warnings per se than individuals without this experience. If they receive a warning their adaptation behaviour is less affected by the forecasted probability of the extreme climate event.
This thesis extends the understanding of human behaviour in light of changing ecosystem dynamics and provides more information regarding how natural resource management can be improved by using forecast and ecological prediction systems. The improved understanding of interactions between human behaviour and ecosystem change contributes to the exchange between policy makers, social scientists, ecologists and resource users
Porous nanoparticle assemblies with enhanced properties for application in electrochemical thin film devices
No full textPorous structures of functional nanoparticles have several properties that are beneficial for their potential applications in optical devices. Structures of this kind can be created in the form of nanoparticle thin films on electrically conductive substrates for electrochemical applications. Mesoporous layers of antimony doped tin dioxide (ATO, SnO2:Sb) nanoparticles, for example, can serve as an optically transparent scaffold, providing electrical conductivity over a broad potential range. Such conductive structures allow electrons to be transported to/from other electrochemically active materials located at the surface of the particles. In electrochromic devices, materials are used that change their optical behavior by oxidation/reduction. It is shown that layers composed of ATO particles with anchored viologen-based redox dyes exhibit remarkable switching times and good long-term stability. Both aspects are related to the rather unusual use of non-intercalating electrolytes, which can be used due to the intrinsic conductivity of ATO. In addition to the optically active layer, a charge storage layer is required in an electrochromic device to achieve high performance. For this purpose, ATO layers can be modified with cerium species that can be switched between +3 and +4 redox states. These layers offer high charge storage capacities with fast response times also in combination with non-intercalating electrolytes. In addition to nanoparticle layers that mainly provide electrical conductivity, the nanoparticles themselves can also have variable properties that depend on the redox state of the atoms in the particles. LaPO4:Ce,Tb nanoparticles can be mentioned as an example where the redox state of the cerium atoms influences the luminescence of the particles. Small amounts of Ce4+ quench the luminescence otherwise exhibited by the particles when the cerium atoms are in the +3 oxidation state. With the help of redox shuttles, the luminescence of non-conductive LaPO4:Ce,Tb nanoparticle layers can be reversibly switched with impressive switching times. The properties of porous structures of functional nanoparticles are, however, not only beneficial for optical devices but also for the synthesis of nanomaterials that show their properties only after calcination at high temperatures. One example is the n-type conductivity of ATO where the particle aggregates formed during calcination cannot be further processed into colloidal solutions. With respect to the latter, it is shown herein that nanoparticle aerogels are suitable for suppressing the formation of large aggregates of nanoparticles during the calcination process. In particular, by assembling aerogels from ATO (and titanium dioxide, TiO2) nanoparticles, colloidal solutions of these particles can be prepared even after calcination at 500 °C
Admissibility and application of the merger clause under Spanish law
No full textThis dissertation represents the first formal analysis of the merger clause into the Spanish legal system genuinely conducted from the Spanish legal perspective. By analyzing the application of the merger clause and its legal effects in a system in which it currently lacks regulation and legal practice, a current gap in research will be closed.
The analysis of current Spanish law, case law and doctrine clearly demonstrates that the “merger clause” is not only an instrument admissible within the Spanish legal system but is also proven to be an enforceable instrument of interpretation due to its indirect application enshrined in Art. 1282 CC. Accordingly, the legal certainty that the merger clause aims to provide to B2B contracts by integrating the parties’ understandings into the written version and discharging prior statements can still be achieved if Spanish law is chosen to govern the contract, despite the absence of formal regulation of merger clauses in current legislation, particularly the Civil Code
Rapid response of vascular plants and insects to restoration of montane grasslands
No full textIntroduction: Industrialization has ushered in massive changes in agriculture. Particularly in low mountain ranges, large-scale afforestation with Norway spruce on traditionally managed, semi-natural grasslands has caused a severe decline in biodiversity. Tree removal, hay transfer and resumption of grazing or mowing are typical measures to re-create species-rich grasslands. The aim of this study was to use vascular plants and three insect taxa (leafhoppers, true bugs, and grasshoppers) as bioindicators to evaluate the success of montane grassland restoration on former spruce forests in Central Europe. In addition, we intended to identify the drivers of species richness within the studied grasslands in order to derive suitable recommendations for habitat management.
Methods: We analyzed two different treatments: (i) grazed restoration sites where trees had been cut and species-rich green hay had been applied (N = 9) and (ii) target sites with a long continuity of low-intensity grazing (N = 9).
Results and Discussion: Our study revealed that all studied taxa responded rapidly to the restoration measures. After a development period of 3 to 5 years, we found no differences in species richness and diversity of leafhoppers, true bugs and grasshoppers (all, target and threatened species). In addition, non-metric multidimensional scaling showed a large overlap in species composition between restoration and target grasslands. Among target and threatened species, vascular plants displayed the same pattern as insects and reached similar values when comparing the two treatments. However, total species richness and diversity of vascular plants were still higher on the target sites and species composition overlapped only partially. Grazing intensity was the predictor with the highest explanatory power in multivariable (Generalized) Linear Mixed-effects Models, being negatively related to species richness of leafhoppers and true bugs. We conclude that the measures implemented were effective in re-establishing target communities of different taxa. The transfer of seed-containing hay enabled or accelerated the development of the vegetation. Insects, on the other hand, were able to recolonize the restored grasslands on their own, given that these sites were embedded in a network of species-rich grasslands. With regard to insects (e.g., leafhoppers and true bugs), it should be ensured that grazing is applied at low intensity
Potenziale von Citizen Science für die Gewässerforschung und Bildung - Ein partizipatives Forschungsprojekt zur Nitratbelastung von Gewässern unter Beteiligung von Wissenschaft, Gesellschaft und Schule
No full textDer Citizen Science-Ansatz, bei dem sich die Öffentlichkeit aktiv an wissenschaftlicher Forschung beteiligt, verspricht als potenziell leistungsfähiges Instrument zur Generierung und Auswertung großer Datenmengen einen bedeutenden Beitrag für die Wissenschaft. Gleichzeitig erlangt Citizen Science in der Bildung eine wachsende Bedeutung, wobei verschiedene Lernziele wie beispielsweise ein höheres Verständnis von der Natur der Naturwissenschaften intendiert werden. Das tatsächliche Potenzial von Citizen Science für die Gewässerforschung und die Wirksamkeit im Bereich der Bildung sind bisher jedoch erst wenig erforscht.
An dieser Stelle setzt ein von den Universitäten Osnabrück und Oldenburg durchgeführtes Citizen Science-Projekt an, in dem gemeinsam mit etwa 800 Schüler:innen und Bürger:innen die Stickstoffbelastung von Gewässern erforscht wurde. Anhand der von den Teilnehmer:innen erhobenen Daten wurde das Potenzial von Citizen Science für die Gewässerforschung, unter anderem zur Analyse räumlicher und zeitlicher Einflussfaktoren auf die Nitratbelastung, untersucht. Darüber hinaus wurden Handlungsempfehlungen für Citizen Science-Projekte im Bereich der Gewässerforschung, beispielsweise in Bezug auf die Repräsentativität des Messnetzes oder die Eignung verschiedener Messmethoden, abgeleitet.
Ergänzend wurde eine quantitative Begleitstudie zur Wirksamkeit von Citizen Science im Bereich der Umweltbildung und naturwissenschaftlichen Schulbildung durchgeführt. Aufgrund der starken Beeinflussung der Studie, unter anderem durch die COVID-19-Pandemie, und aufgrund zu kleiner Stichproben konnten die Wirkungen auf das Umweltbewusstsein sowie auf das Verständnis der Natur der Naturwissenschaften, die motivationale Regulation, das Interesse, die Selbstwirksamkeit und das Selbstkonzept nicht abschließend überprüft werden. Dennoch liefert die Begleitstudie erste Hinweise darauf, dass die Teilnahme an einem Citizen Science-Projekt einen positiven Einfluss auf das Umweltverhalten und die Umweltkenntnisse in Bezug auf den Gewässerschutz haben kann