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Aushandlungsprozesse der Deutschen Kolonialgesellschaft und des Frauenbundes im kolonialen Migrations- und Genderregime
No full textIn der Zeit zwischen 1907 und 1914 entsandte der Frauenbund der Deutschen Kolonialgesellschaft (FB) in Kooperation mit der Deutschen Kolonialgesellschaft (DKG) mehrere hundert deutsche weiße Frauen als Dienstmädchen in die deutschen Kolonien. Damit stellen die beiden Organisationen zwei zentrale nichtstaatliche Akteur*innen im deutschen kolonialen Migrations- und Genderregime dar, was die These nahelegt, dass die DKG und der FB bedeutenden Einfluss auf die Bedingungen nahmen, unter denen weibliche Migration in die deutschen Kolonien zu dieser Zeit stattfand. Mit Hilfe der Historischen Diskursanalyse wird in diesem Working Paper untersucht, welche Bedeutungen von Migration zwischen der DKG und dem FB bei der Entsendung deutscher weißer Frauen ausgehandelt wurden. Als Grundlage der Analyse werden Protokolle, Schriftverkehr, Verträge sowie weitere Quellen der am Beziehungsdreieck DKG – FB – Migrantinnen beteiligten Akteur*innen herangezogen. Dadurch werden die vergeschlechtlichten Praktiken und Machtgefüge innerhalb der Institutionen, aber auch zwischen den Institutionen und den Migrantinnen sichtbar. Die Arbeit unterliegt dabei einer postkolonialen, feministischen Kritischen Weißseins-Perspektive
Caregiving in Contexts of Poverty and Migration in Three Ecosocial Settings in Costa Rica
Get PDFThis dissertation addresses the question of how contextual conditions and caregiving networks interact in contexts of poverty and migration in three ecosocial settings in Costa Rica. Based on the tenets of the ecocultural model of development and informed by the bioecological model of development, a research design involving 17 local cultural informants and 48 local and migrant mothers with children aged 12 to 24 months old is applied to account for contextual dynamics and their interplay with caregiving arrangements. Due to the exploratory nature of the study, an interview-based, culturally sensitive approach is adopted.
The findings are organized along three broad dimensions: how care is distributed, how caregiving networks interact with the immediate environment, and how caregiving networks interact with institutions. The analysis provides evidence on how the combined coordination of the identified contextual dimensions (institutional frameworks, existing livelihood solutions, perceived social cohesion, social expectations regarding the distribution of care and income-generating tasks, and settlement patterns that affect the availability of caregivers) varies across the selected contexts and subsamples to configure specific caregiving arrangements. These findings enrich the explanatory scope of the ecocultural development model and introduce relevant categories for assessing contextual conditions and their influence on family life.
The study advocates for the further development of contextually informed interventions that recognize and respond to the local conditions of target communities, particularly in non-Western contexts and among populations experiencing poverty and migration. Recommendations are made to continue this line of research based on the proposed theoretical contributions
Physics-Aware Shadow Compensation for Hyperspectral Imagery Based on Spectral Unmixing and Data Fusion
Get PDFImaging spectrometers, also known as hyperspectral sensors, acquire reflectance spectra from targets on ground in up to hundreds of narrow spectral bands over a wide range of the electromagnetic spectrum. Having an increased spectral resolution with respect to other kinds of optical imagery, such as panchromatic and multispectral, hyperspectral data can discriminate materials more accurately and thus allow new applications in remote sensing. Nevertheless, the Earth's surface topography causes the occlusion of incoming illumination for ground targets, leading to shadow effects in the acquired images. Shadows can considerably decrease the performance of image analysis algorithms, and have thus drawn growing attention in the literature. Although shadow issues have been discussed for some kinds of optical sensors, few works have addressed these effects and their unique challenges in hyperspectral imagery, demanding novel shadow-aware methods. This dissertation proposes three robust algorithms, built on one another, for tackling shadow effects in hyperspectral images. The dissertation first presents a shadow detection and removal framework based on physical assumptions and spectral unmixing. The main idea is to model the shadow formation using a few physically interpretable shadow-related parameters, and apply them in order to detect and remove shadows. Specifically, a novel physics- and shadow-aware spectral mixing model is proposed, which considers how material spectra and shadows contribute to the individual pixel spectrum measured by the sensor. The described spectral mixing model can tackle only simple scenarios because it assumes simplified optical interactions and illumination conditions on ground. Thus, the following work improves the model to handle more complicated and generalized cases. The improved model regards the entire radiative propagation process, from illumination sources to the backscattered signals recorded by the sensor, using a discrete-time stochastic process and physical assumptions. As the model's complexity increases, resolving unknown parameters via spectral unmixing becomes an ill-posed problem. Hence, a novel spectral unmixing approach for a robust estimation based on the Alternating Direction Method of Multipliers (ADMM) and data fusion is proposed. The ADMM decomposes a complex optimization problem into sub-problems, each of which is easier to solve. Digital Surface Models (DSMs) are also employed in this approach, as they are insensitive to shadow effects. In addition, spatial relationships between neighboring pixels are considered. The proposed methods have been extensively evaluated using several simulated and real datasets in small and large regions. Results demonstrate that the proposed research works are effective and superior to state-of-the-art methods, both qualitatively and quantitatively
Effect of stress caused by pulsed electric field or mild heat on the performance of yogurt starter culture and characteristics of final products
Get PDFThis thesis was dedicated to the investigation of the influence of stress through mild pulsed electric fields (PEF) and heat treatment to yogurt starter culture Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus on the fermentation ability and the final product set-style yogurt.
The first part of the thesis focuses on the theoretical background of the topic. For stress treatment of the starter culture and for yogurt production, a profound knowledge of the performance of the lactic acid bacteria (LAB), the principles of yogurt fermentation, the milk proteins, and the reaction on changing environmental conditions is essential.
The second part of the thesis is addressed to the practical work and is divided into two main topics, namely stress pre-treatment with PEF and heat. PEF stress was investigated with regards to the performance of PEF pre-stressed bacteria in terms of acidification activity and cell count kinetics. Rheological analysis was performed by texture and syneresis measurements and amount of α-amino acids was analyzed. Furthermore, the influence of freezing with liquid nitrogen on the fermentation abilities of the PEF treated starter culture was analyzed. The results revealed that the application of PEF to yogurt starter culture as a pre-treatment to milk fermentation can alter its performance and may be used to modify the properties of the final product without changing the fermentation conditions or starter culture. Stressed bacteria showed significant changes in rheological properties of set-style yogurt, either freshly PEF pre-treated starter culture od flash frozen and stored PEF pre-treated culture. Additionally, volatile compounds were analyzed with varying results for the polar and nonpolar metabolome.
The heat stressed part is addressed to the effects of different heat pre-treatments to the starter culture, regarding their performance. According to the PEF treated part of the thesis, viable cell count, fermentation kinetics, rheological properties and proteolytic activity was measured. Additionally, volatile compounds were determined. The results for heat treated starter culture revealed that application of heat to yogurt starter culture can alter its performance and showed differences in rheological properties, by lower syneresis and more rigid yogurt samples. Significant differences in volatile compounds have been seen, depending on the applied heat treatment.
This research provides new information regarding the impact of stress treatment on starter culture and their fermentation ability for set-style yogurt and therefore, these technologies can be of high importance to the dairy industry to modify product characteristics and enhance the mechanical resilience of the products to transport
Digitalisierung in der Hochschulbildung – Analyse von individuellen Einflussfaktoren zur Nutzung eines digitalen Studienassistenten und Open Educational Resources
No full textZiel dieser Dissertation war es, individuelle Einflussfaktoren zur Nutzung eines Digitalen Studienassistenten (DSA) und Open Educational Resources (OER) im Hochschulkontext zu untersuchen. Die Forschungsfragen und Zielsetzungen beleuchten diverse Einflussfaktoren, welche sich in den einzelnen Beiträgen widerspiegeln. Beitrag 1 zeigt hier die Forschungslücke auf, während die Beiträge 2, 3 und 4 Anforderungen, Erwartungen, Erfolgsfaktoren und Barrieren aus der Sicht der Nutzer analysieren. Die Beiträge 5 und 6 setzen sich explizit mit ethischen Faktoren zur Nutzung auseinander. Schließlich werden in den Beiträgen 7 und 8 auch die Perspektiven von Dozenten als Nutzer und Ersteller von OER betrachtet.
Die Ergebnisse der Arbeit zeigen, dass es sowohl technische als auch institutionelle Barrieren gibt, die die Nutzung von DSA und OER einschränken. Auch wurden Anforderungen, Erwartungen und ethische Faktoren als entscheidende Einflussgrößen zur Nutzung eines Studienassistenten identifiziert. Darüber hinaus wurde die Sichtweise der Dozenten als Nutzer und Ersteller von OER berücksichtigt. Diese Erkenntnisse sind von großer Bedeutung für das Forschungsgebiet, da sie nicht nur die Herausforderungen aufzeigen, sondern auch Empfehlungen zur Förderung der Nutzung von DSA und OER geben
Correlation of non-invasive psycho-physiological and skin-physiological measures
Get PDFIntroduction: Psychological stress alters epidermal barrier function. While intensive studies on the underlying mechanism have been performed in mice, human studies are limited. Non-invasive skin-physiology measures have not yet been directly linked to non-invasive psycho-physiological assessments.
Methods: Standard measures of (I) transepidermal water loss prior to and after experimental barrier perturbation via tape stripping, (II) skin surface pH, (III) electrodermal activity, and (IV) heart rate function were taken over a 24 h time period. To document perceived stress, a standardized stress self-assessment questionnaire, namely the Trierer Inventar zum chronischen Stress (TICS), was utilized.
Results: Twenty healthy, Caucasian (Fitzpatrick skin phototype I-II), female volunteers (21–32 years, mean age 27, SD = 3.67 years) were included in this study (random sample). Significant correlations were shown for 24 h delta transepidermal water loss changes, that is, barrier repair kinetics (sympathetic activity) and heart rate variability (parasympathetic activity). Further correlations were noted for electrodermal activity and skin surface pH. Perceived stress, as documented by the TICS questionnaire, did not correlate with psycho- and skin physiological parameters, respectively. Conclusion: The presented approaches may provide a basis for non-invasive objective research on the correlation between psychological stressors and epidermal barrier function
Long-lived, pulse-induced transient absorption in LiNb1−xTaxO3 (0 ⩽ x ⩽ 1) solid solutions: the case of three intrinsic defect sites for electron localization with strong coupling
Get PDFFemto-/nanosecond pulse-induced, red and near-infrared absorption is studied in LiNb1−xTaxO3 (0 ⩽ x ⩽ 1, LNT) solid solutions with the aim of studying transient optical nonlinearities associated with the formation, transport and recombination of optically generated small bound electron polarons with strong coupling to the lattice. As a result, a pronounced, long-lived transient absorption is uncovered for LNT which exceeds lifetimes and starting amplitudes of LiNbO3 (LN) and LiTaO3 (LT) by a factor of up to 100 and 10, respectively. The transients reveal a stretched-exponential decay behavior and a thermally activated process which provide strong evidence for an underlying hopping transport mechanism of small bound polarons. All findings are discussed in comparison to the model systems LN and LT within the framework of appropriate band models and optical generation of polarons via two-photon excitation. To explain the significant differences, the simultaneous presence of Nb5+ Li , Ta5+ Li antisites, and Ta5+ V interstitial defects, i.e. a mixture of the intrinsic defects widely established for LN and LT, is assumed for LNT
Now they can cope? The Green Deal and the contested meaning of sustainability in EU sectoral governance
Get PDFThe European Union (EU) has long discursively positioned itself as a global frontrunner for sustainability and climate protection. Nevertheless, substantive progress toward sustainability goals has not been reached in several governance areas, such as transport and mobility. Especially at the local scale, the highly complex and technocratic EU policy framework is confronted with increasingly polarized claim-making regarding ecological, social and economic problems. With its recent Green Deal governance architecture, the European Commission has sought to address this ideational and institutional fragmentation and resulting stalemate toward reaching “climate neutrality” by proposing ambitious sectoral policies and new governance instruments. This problem-driven paper exploratively investigates the ongoing reconfigurations the Green Deal induces within EU governance. Using the example of the urban mobility sector and employing an interpretive analysis of key policy documents and expert/stakeholder interviews, the paper links the literatures on EU governance architectures and norm dynamics. It discusses potentials and pitfalls for meaning-making processes in times of the socioecological polycrisis. Notably, it critically evaluates the Green Deal’s capacity to open and sustain spaces for translating sustainability across horizontally and vertically fragmented realms of EU governance
Adamantylglycine as a high-affinity peptide label for membrane transport monitoring and regulation
Get PDFThe non-canonical amino acid adamantylglycine (Ada) is introduced into peptides to allow high-affinity binding to cucurbit[7]uril (CB7). Introduction of Ada into a cell-penetrating peptide (CPP) sequence had minimal influence on the membrane transport, yet enabled up- and down-regulation of the membrane transport activity
Early childhood teachers' feedback in natural mathematical learning situations: Development and validation of a detailed category system
Get PDFIn many countries, early mathematical learning takes place in informal and play-based situations. To support children's mathematical learning, the interactions that occur in the daily contact between the early childhood (EC) teacher and the child in kindergarten play an important role. In these interactions, the feedback provided by the EC teacher is considered to have effects on learning. However, how EC teachers actually give specific or non-specific feedback in everyday activities and play situations with a potential for mathematical learning (natural mathematical learning situations) has been little studied so far. To comprehensively characterize the EC teacher's feedback in natural mathematical learning situations, the current study developed a detailed category system based on categories from previous feedback studies, conducted under various conditions and with different objectives. To verify our category system, we coded mathematical teacher-child interactions (N = 162). The coding provided us with evidence that the category system allows to capture the given feedback in natural mathematical learning situations reliably and in detail. The category system can be useful for further research examining the effects of naturally given feedback on children's mathematical learning and, in the long run, for training teachers in the use of potentially supportive feedback in natural learning situations