500 Naturwissenschaften und Mathematik
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Diese Arbeit wertet Leistellendaten von zwei Landkreisen aus und untersucht dabei, welche Veränderung hinsichtlich der mittleren Anzahl und Dauer von Rettungsdiensteinsätzen im Zeitraum der COVID-19-Pandemie aufgeteilt nach Stunden- und Tageskategorien besteht. Anschließend werden die Veränderungen von Anzahl und Dauer beider Landkreise verglichen, um diese auf Unterschiede zu prüfen. Da in der aktuellen Literatur unzureichend dargelegt ist, wie Veränderungen des Einsatzanzahl oder -dauer im Rettungsdienst zwischen Kreisen sowie über die Tage und Tagesstunden verteilt sind, trägt diese Untersuchung dazu bei diese Forschungslücke zu schließen. Die statistische Auswertung der Leitstellendaten umfasst mehrere Schritte, sodass zuerst eine Aufbereitung durchgeführt wird, bevor die mittlere Einsatzanzahl und -dauer für vier Zeiträume sowie die prozentuale Veränderung zwischen einem Zeitraum vor und drei Zeiträumen während der Pandemie ermittelt werden. Im Anschluss wird die Veränderung mittels Kruskal-Wallis-Test beziehungsweise Varianzanalyse nach Welch auf Signifikanz überprüft. Abschließend erfolgt ein qualitativer Vergleich zwischen den Kreisen. Die Untersuchung zeigt, dass hinsichtlich Einsatzanzahl und -dauer zu allen drei Zeitraumen in der Pandemie Zu- und Abnahmen auftreten. Die Anzahl nimmt zum ersten Zeitraum in beiden Kreisen überwiegend ab, sowie zum vierten Zeitraum mehrheitlich zu, während zum zweiten Zeitraum im Lahn-Dill-Kreis eine häufigere Abnahme und im Main-Taunus-Kreis eine geringfügig überwiegende Zunahme vorliegt. Die Einsatzdauer unterliegt zum zweiten Zeitraum im Lahn-Dill-Kreis einer überwiegenden Zunahme und im Main-Taunus-Kreis einer überwiegenden Abnahme, während zum dritten sowie vierten Zeitraum in beiden Kreisen einer Steigerung stattfindet. Im Vergleich beider Gebietskörperschaften zeigen bei der Einsatzanzahl die Veränderungen zum zweiten und vierten Zeitraum und bei der Dauer die Veränderungen zum dritten und vierten Zeitraum mit der Mehrheit der Stundenkategorien Gemeinsamkeiten. Das Pandemiegeschehens sowie die nichtpharmazeutischen Interventionen sowie deren Folgen stellen Faktoren für die Veränderung von Einsatzanzahl und -dauer dar. Die geografische Lage sowie die lokale Ausgestaltung von Rettungsdienst und Krankentransport begründen, zusätzlich zu den oben genannten Aspekten, Unterschiede zwischen den Kreisen.
Circular economy (CE) has received considerable interest in recent years as a strategy to resolve some of our modern urban resource challenges, and circular city models often incorporate systems of urban agriculture in their design. Much work has analyzed the benefits of urban agriculture for creating a resilient food system and as a strategy for supporting urban green space and social cohesion, however, the contributions from business models that operate within urban agriculture have not been thoroughly studied. Many urban agriculture businesses often claim high levels of resource recycling and material circularity, though whether a resource efficiency throughout the entire product lifetime (including energy and material footprint for the cultivation equipment) in comparison to current industrial strategies is truly feasible or even possible is still to be debated. This thesis builds upon work that incorporates social dimensions of CE definitions and begins to research whether the potential resource efficiency contradiction can be justified as to make urban agriculture a valid approach for circular city design. This study examined an urban mushroom farm that implements a circular business model. A qualitative summary of the business operations and resource flows were unpacked and sorted into 24 socio-economic contributions based on their interpreted relevance. The interpreted data shows that an urban agriculture business model can contribute to the building blocks of a CE through economic, ecological, social, and spatial contributions. While these contributions can contribute positively to the operationalization of CE, potential trade-offs regarding resource efficiency, use of urban space, and investment priorities need to be considered and addressed to avoid a possible watering down or greenwashing of the CE concept.
Stable recombinant mammalian cells are of growing importance in pharmaceutical biotechnology production scenarios for biologics such as monoclonal antibodies, growth and blood factors, cytokines and subunit vaccines. However, the establishment of recombinant producer cells using classical stable transfection of plasmid DNA is hampered by low stable gene transfer efficiencies. Consequently, subsequent selection of transgenic cells and the screening of clonal cell populations are time- and thus cost-intensive. To overcome these limitations, expression cassettes were embedded into transposon-derived donor vectors. Upon the co-transfection with transposase-encoding constructs, elevated vector copy numbers stably integrated into the genomes of the host cells are readily achieved facilitating under stringent selection pressure the establishment of cell pools characterized by sustained and high-yield recombinant protein production. Here, we discuss some aspects of transposon vector technologies, which render these vectors promising candidates for their further utilization in the production of biologics.
Despite intensive research over the last three decades, it has not yet been possible to bring an effective vaccine against human immunodeficiency virus (HIV) and the resulting acquired immunodeficiency syndrome (AIDS) to market. Virus-like particles (VLP) are a promising approach for efficient and effective vaccination and could play an important role in the fight against HIV. For example, HEK293 (human embryo kidney) cells can be used to produce virus-like particles. In this context, given the quality-by-design (QbD) concept for manufacturing, a digital twin is of great importance for the production of HIV-Gag-formed VLPs. In this work, a dynamic metabolic model for the production of HIV-Gag VLPs was developed and validated. The model can represent the VLP production as well as the consumption or formation of all important substrates and metabolites. Thus, in combination with already described process analytical technology (PAT) methods, the final step towards the implementation of a digital twin for process development and design, as well as process automation, was completed.
Aerobic microbial cultivations are industrially important group of processes and pose challenges for the reactor design. In particular, estimation of industrial scale conditions is difficult from laboratory and pilot scale data. Due to complex interaction of gas/liquid phase hydrodynamics, mass transfer parameters and microbial metabolism, both improvement of modelling tools and reactor design are desired. We present an approach to estimate growth conditions in industrial scale reactor by combining black-box metabolic models with CFD-model.
The reactor type used here is Outotec OKTOP9000®, which is used in the industrial hydrometallurgical processes at 900 m3 scale. It is adopted to a laboratory setting and compared to stirred tank reactor (STR) in gas dispersion, mass transfer and yeast cultivation experiments. In addition, a kinetic model for the yeast growth is developed based on literature sources and validated by the laboratory scale batch cultivations. This kinetic model is used along with CFD-model that is developed to describe the flow and mass transfer conditions in the industrial scale reactor.
The laboratory scale experiments show the feasibility of OKTOP9000® reactor when compared to STR, particularly with improved gas handling capacity. The modelling approach shows qualitatively similar behavior in the large scale simulations when compared to laboratory scale cultivations.
Thioredoxin (Trx) overexpression is known to be a cause of chemotherapy resistance in various tumor entities. However, Trx effects on resistance are complex and depend strictly on tissue type. In the present study, we analyzed the impact of the Trx system on intrinsic chemoresistance of human glioblastoma multiforme (GBM) cells to cytostatic drugs. Resistance of GBM cell lines and primary cells to drugs and signaling inhibitors was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Impact of Trx inhibition on apoptosis was investigated by proteome profiling of a subset of proteins and annexin V apoptosis assays. Trx-interacting protein (TXNIP) was overexpressed by transfection and protein expression was determined by immunoblotting. Pharmacological inhibition of Trx by 1-methyl-2-imidazolyl-disulfide (PX-12) reduced viability of three GBM cell lines, induced expression of active caspase-3, and reduced phosphorylation of AKT-kinase and expression of β-catenin. Sensitivity to cisplatin could be restored by both PX-12 and recombinant expression of the upstream Trx inhibitor TXNIP, respectively.
In addition, PX-12 also sensitized primary human GBM cells to temozolomide. Combined inhibition of Trx and the phosphatidylinositide 3-kinase (PI3K) pathway resulted in massive cell death. We conclude that the Trx system and the PI3K pathway act as a sequential cascade and could potentially present a new drug target.
AbstractThis paper discusses the comparison of two methods to achieve thermal comfort utilising air conditioning (AC) system in a small indoor space – adaptive control and fuzzy control. Thermal comfort indoors is performed to provide comfortability individually or for a group of people. Due to the small indoor space which usually a bit cramped, crowded and less airy, the ambience can be very uncomfortable either for doing sedentary or active work, thus the AC system can be very useful to provide thermal comfort. Both methods can be utilised depending on how thermal comfort is viewed and how the level of thermal comfort is decided. Every method has its own advantage and limitations, and will be covered in this paper as well.
The southeast of Córdoba province used to be originally covered by hundreds of wetlands that got heavily modified or drained in the last few decades. Since wetlands provide various important ecosystem services (ESS) for human well-being, their degradation created several problems in La Picasa basin, among which floods are the most obvious one. The wise use of wetlands is increasingly acknowledged to be part of nature-based solution approaches reducing disaster risk. However, in the study area these approaches remain a relatively new concept to decision makers and the lack of knowledge on their effectiveness and implementation process poses a serious barrier to their adoption.
To overcome this obstacle, this dissertation applies an ESS perspective on the current problems of La Picasa basin and sets it in a context of socio-ecological system (SES) theory. A comprehensive analysis of (1) the role wetlands have played in the historic development of the SES, (2) important stakeholder dynamics that create opportunities or restrictions for the conservation of wetlands and (3) possible management approaches to inverse negative ESS trade-offs and feedback loops, was performed.
Results demonstrate that the current problems of floods have both natural and anthropogenic causes. In this regard, wetlands hold a vital role in the complex historic interactions between the social and ecological drivers of changes in the water balance. Although a social network between stakeholders exists, several conflicts prevent a proper functioning of a basin-wide integrated management concept based on wetland restoration. Nature-based solution approaches, putting wetlands in the center of attention of future management strategies, were found to hold a high potential to reduce the risk of floods and, as a side-effect boost biodiversity and habitat quality in the study area.
Wetlands offer different ecosystem services that contribute to human well-being (Kovács et al., 2015). According to the Ramsar Convention Secretariat (2018) wetland located in urban areas have been threatened by several activities such as drainage, pollution, encroachment, agriculture, among others. On the other hand, wetland degradation reduces the resilience of hazards like floods and storm surges (Kumar et al., 2017). For that reason, ecosystem-based disaster risk reduction (Eco-DRR) is an important strategy which enhances the conservation and restoration of ecosystems to reduce disaster risk aiming to sustainable development and resilience (Estrella & Saalismaa, 2013). Despite international recognition of the importance of wetlands, urban wetlands have diminished their capacity to cope with flood threats (Boyer and Polasky, 2006) due to the aforementioned human impacts.
That is why this thesis aimed to identify the role of urban wetlands in Bogota, Colombia, that has an urban wetland complex that is recognised as a Ramsar site in 2018. However, wetlands in the city reduced its area from 50.000 hectares to less than 800, approximately, in less than 40 years, mainly because of urban expansion and encroachment (IDIGER, 2018). To achieve this objective, an analysis of the city’s risk management framework was conducted, as well as a stakeholder analysis based on semi-structured interviews and a spatial-temporal analysis for the period 1998-2017, for which the Jaboque wetland was used as a case study. This wetland is located near the Bogotá River and is in the area threatened by flooding.
It was possible to determine that national and district policies on wetlands, biodiversity, and climate change adaptation address some ecosystem functions. Still, disaster risk reduction is not strongly linked to them. Thus, based on the case study, the wetlands in Bogota have not played a decisive role in flood risk management in the city.
This study aimed to simulate the sector-coupled energy system of Germany in 2030 with the restriction on CO2 emission levels and to observe how the system evolves with decreasing emissions. Moreover, the study presented an analysis of the interconnection between electricity, heat and hydrogen and how technologies providing flexibility will react when restricting CO2 emissions levels. This investigation has not yet been carried out with the technologies under consideration in this study. It shows how the energy system behaves under different set boundaries of CO2 emissions and how the costs and technologies change with different emission levels. The study results show that the installed capacities of renewable technologies constantly increase with higher limitations on emissions. However, their usage rates decreases with low CO2 emission levels in response to higher curtailed energy. The sector-coupled technologies behave differently in this regard. Heat pumps show similar behaviour, while the electrolysers usage rate increases with more renewable energy penetration. The system flexibility is not primarily driven by the hydrogen sector, but in low CO2 emission level scenarios, the flexibility shifts towards the heating sector and electrical batteries.