University of Siegen
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Publication Access status: Open Access , Beziehung auf Bewährung?!(2023)Baldsiefen, Anna MerleDas Ziel einer Bewährungsunterstellung ist das straffreie Leben der verurteilten Person. Oftmals wird das Soziale Netzwerk zu einer entscheidenden Stellschraube bei der Strafaussetzung. In die sozialpädagogische Arbeit der Bewährungshilfe wird es vielfach (un-)mittelbar miteinbezogen. Ob und welche (nicht-)intendierten Folgen sich aus der Sozialen Hilfe für die sozialen Beziehungen der Adressat*innen ergeben, wird in dem Buch empirisch beleuchtet. Dabei rücken insbesondere Paarbeziehungen und das Verhältnis zwischen Fachkraft und Adressat*in in den Fokus.Source Type:Doctoral Thesis9 9 - Some of the metrics are blocked by yourconsent settings
Publication Access status: Open Access , Remote control of the synthesis of a [2]rotaxane and its shuttling via metal-ion translocation(2019); ; Remote control in an eight-component network commanded both the synthesis and shuttling of a [2]rotaxane via metal-ion translocation, the latter being easily monitored by distinct colorimetric and fluorimetric signals. Addition of zinc(II) ions to the red colored copper-ion relay station rapidly liberated copper(I) ions and afforded the corresponding zinc complex that was visualized by a bright sky blue fluorescence at 460 nm. In a mixture of all eight components of the network, the liberated copper(I) ions were translocated to a macrocycle that catalyzed formation of a rotaxane by a double-click reaction of acetylenic and diazide compounds. The shuttling frequency in the copper-loaded [2]rotaxane was determined to k298=30 kHz (ΔH≠=62.3±0.6 kJ mol−1, ΔS≠=50.1±5.1 J mol−1 K−1, ΔG≠298=47.4 kJ mol−1). Removal of zinc(II) ions from the mixture reversed the system back generating the metal-free rotaxane. Further alternate addition and removal of Zn2+ reversibly controlled the shuttling mode of the rotaxane in this eight-component network where the ion translocation status was monitored by the naked eye.Source Type:Article1 7 - Some of the metrics are blocked by yourconsent settings
Publication Access status: Open Access , High-speed focus-induced photoresponse in amorphous silicon photodetectors for optical distance measurementsThe Focus-Induced Photoresponse (FIP) enables 3D sensing capabilities by evaluating the irradiance dependent non-linear detector response in defect-based materials. Since this advantage is intricately associated to a slow response, the electrical bandwidth of previous FIP sensors is limited to a few kHz only. We report the FIP in amorphous silicon pin photodiodes and propose a sensor read out based on a harmonics analyses. We achieve modulation frequencies of 500 kHz and a non-linear beat frequency detection up to at least 3.5 MHz, surpassing the bandwidth of state-of-the-art architectures by at least a factor of 175. The FIP sensors further achieve signal-to-noise ratios of ∼50 dB, depth resolutions of at least 5.4 mm at 126 cm and a DC FIP detection limit of 1.3 μW/mm2.Source Type:Article2 9 - Some of the metrics are blocked by yourconsent settings
Publication Access status: Open Access , X-ray diffraction with micrometre spatial resolution for highly absorbing samplesX-ray diffraction with high spatial resolution is commonly used to characterize (poly)crystalline samples with, for example, respect to local strain, residual stress, grain boundaries and texture. However, the investigation of highly absorbing samples or the simultaneous assessment of high-Z materials by X-ray fluorescence have been limited due to the utilization of low photon energies. Here, a goniometer-based setup implemented at the P06 beamline of PETRA III that allows for micrometre spatial resolution with a photon energy of 35 keV and above is reported. A highly focused beam was achieved by using compound refractive lenses, and high-precision sample manipulation was enabled by a goniometer that allows up to 5D scans (three rotations and two translations). As experimental examples, the determination of local strain variations in martensitic steel samples with micrometre spatial resolution, as well as the simultaneous elemental distribution for high-Z materials in a thin-film solar cell, are demonstrated. The proposed approach allows users from the materialsscience community to determine micro-structural properties even in highly absorbing samples.Source Type:Article3 10 - Some of the metrics are blocked by yourconsent settings
Publication Access status: Open Access , Einstellungen von Lehramtsstudierenden zu sprachlich-kultureller Vielfalt in der Schule(2022)Kaplan, InaSprachlich-kulturelle Vielfalt spielt in der Schule auf mehreren Ebenen eine Rolle. Sie lässt sich zum einen auf die Schülerinnen und Schüler beziehen, für die Deutsch eine Zweitsprache darstellt, und zum anderen auf den Unterricht in sprachlich-kulturell vielfältigen Klassen. Die empirische Studie untersucht, wie Lehramtsstudierende sprachlich-kulturelle Vielfalt bewerten und welche Motive, Erfahrungen und Hintergründe dabei eine Rolle spielen. Mithilfe von Interviews werden Einstellungen von Lehramtsstudierenden zu den genannten Aspekten erhoben und eine Typologie dieser Einstellungen entwickelt. Auch ihre Einstellungen zu Lerngelegenheiten im Rahmen des DaZ-Moduls werden einbezogen, ein bisher in der Forschung kaum untersuchter Aspekt. Insbesondere die Verknüpfung mit der zuvor entwickelten Typologie bietet ein besonderes Potenzial zur Reflexion und Weiterentwicklung der Lehrkräfteausbildung.Source Type:Doctoral Thesis4 8 - Some of the metrics are blocked by yourconsent settings
Publication Access status: Open Access , Advances in biomimetic photoelectrocatalytic reduction of carbon dioxide(2022)Emerging photoelectrocatalysis (PEC) systems synergize the advantages of electrocatalysis (EC) and photocatalysis (PC) and are considered a green and efficient approach to CO2 conversion. However, improving the selectivity and conversion rate remains a major challenge. Strategies mimicking natural photosynthesis provide a prospective way to convert CO2 with high efficiency. Herein, several typical strategies are described for constructing biomimetic photoelectric functional interfaces; such interfaces include metal cocatalysts/semiconductors, small molecules/semiconductors, molecular catalysts/semiconductors, MOFs/semiconductors, and microorganisms/semiconductors. The biomimetic PEC interface must have enhanced CO2 adsorption capacity, preferentially activate CO2, and have an efficient conversion ability; with these properties, it can activate C=O bonds effectively and promote electron transfer and C-C coupling to convert CO2 to single-carbon or multicarbon products. Interfacial electron transfer and proton coupling on the biomimetic PEC interface are also discussed to clarify the mechanism of CO2 reduction. Finally, the existing challenges and perspectives for biomimetic photoelectrocatalytic CO2 reduction are presented.Source Type:Article6 4 - Some of the metrics are blocked by yourconsent settings
Publication Access status: Open Access , Novel methodologies for multiaxial strain measurements with piezoresistive films based on graphene nanoplateletsMany recent investigations in the context of graphene nanoplatelets (GNPs) coatings report surface strain measurements by using piezoresistive sensing capabilities. An often underestimated problem is that the strain field is unknown and the principal strain components as well as their orientations must be determined. Herein, GNP films subjected to multiaxial strain are examined. Experimental results show that although the sensitivity to longitudinal strain is the highest, the ratio between transverse and longitudinal sensitivity exceeds 0.5. The sensitivity to shear strain is much lower. A model assisted study of a random network provides additional guidelines for the different electromechanical sensitivities. In practice, the GNP film is usually subjected to different strains simultaneously so that the multiaxial strain measurement becomes difficult. Therefore, two novel approaches for sensing plane strain components with circular GNP films are developed and successfully verified in experiments. The numerical approach is called strain-differential electrical impedance tomography (SD-EIT), where the proposed piezoresistive model elementwise in a finite element model is implemented and the strain components of a strain rosette are reconstructed. Moreover, an analytical approach is derived from SD-EIT and exhibits further the opportunity to detect anomalies within the piezoresistive sensing behavior of GNP films.Source Type:Article1 13 - Some of the metrics are blocked by yourconsent settings
Publication Access status: Open Access , Project DECIDE, part 1: increasing the amount of valid advance directives in people with Alzheimer’s disease by offering advance care planning - a prospective double-arm intervention studyBackground Everybody has the right to decide whether to receive specific medical treatment or not and to provide their free, prior and informed consent to do so. As dementia progresses, people with Alzheimer’s dementia (PwAD) can lose their capacity to provide informed consent to complex medical treatment. When the capacity to consent is lost, the autonomy of the affected person can only be guaranteed when an interpretable and valid advance directive exists. Advance directives are not yet common in Germany, and their validity is often questionable. Once the dementia diagnosis has been made, it is assumed to be too late to write an advance directive. One approach used to support the completion of advance directives is ‘Respecting Choices’®—an internationally recognised, evidence-based model of Advance Care Planning (ACP), which, until now, has not been evaluated for the target group of PwAD. This study’s aims include (a) to investigate the proportion of valid advance directives in a memory clinic population of persons with suspected AD, (b) to determine the predictors of valid advance directives, and (c) to examine whether the offer of ACP can increase the proportion of valid advance directives in PwAD. Method We intend to recruit at least N = 250 participants from two memory clinics in 50 consecutive weeks. Of these, the first 25 weeks constitute the baseline phase (no offer of ACP), the following 25 weeks constitute the intervention phase (offer of ACP). The existence and validity of an advance directive will be assessed twice (before and after the memory clinic appointment). Moreover, potential predictors of valid advance directives are assessed. Discussion The results of this study will enhance the development of consent procedures for advance directives of PwAD based on the ACP/Respecting Choices (R) approach. Therefore, this project contributes towards increasing the autonomy and inclusion of PwAD and the widespread acceptance of valid advance directives in PwAD.Source Type:Article3 12 - Some of the metrics are blocked by yourconsent settings
Publication Access status: Open Access , Experiences with teachers in childhood and their association with wellbeing in adulthood(2022); Background: Prior research mainly focussed on the impact of the teacher-student relationship on teachers emotions and wellbeing. Current data shows a relationship between the quality of the teacher-student relationship and children’s mental health. Unfortunately, it has not yet been investigated whether meaningful experiences with teachers also have an impact on students’ well-being and whether an effect can still be found in adulthood. This work examines the impact of meaningful experiences with teachers during childhood and adolescence on the well-being of adults. Methods: The data in this study was collected by using a questionnaire. The current well-being of the participants was assessed with measures of life satisfaction, resilience, anxiety, stress, depressiveness, and self-esteem. Also, participants were asked to briefly write about their most meaningful experiences with teachers and rate them regarding their valence. These experiences were categorized into seven categories using a summarizing content analysis. We then conducted a statistical analysis with the data obtained. Results: The results showed a highly significant correlation between the participants’ self-esteem and the valence ratings of their experiences. Furthermore, the experience category had a substantial effect on individual self-esteem. Overall, this study demonstrated that a relationship exists between the well-being of adults and their experiences with teachers during childhood and adolescence. Conclusion: The results of this study call for a reflective, fair, authentic, and empathetic approach to students. Accordingly, teachers should be intensively trained to establish a relationship with their students that is characterized by appreciation and empathy.Source Type:Article3 5 - Some of the metrics are blocked by yourconsent settings
Publication Access status: Open Access , No “carry-over” effects of tracking devices on return rate and parameters determining reproductive success in once and repeatedly tagged common swifts (Apus apus), a long-distance migratory bird(2022); Background: To understand life-history strategies in migratory bird species, we should focus on migration behaviour and possible carry-over effects on both population and individual level. Tracking devices are useful tools to directly investigate migration behaviour. With increased use of tracking devices, questions arise towards animal welfare and possible negative effects of logger on birds. Several studies were conducted to address this question in birds that were tagged and tracked for one complete non-breeding season including migration but with mixed results. To detect individual-based decisions regarding migration strategy, we need to track the same individuals several times. So far, there are no studies investigating effects of repeatedly tagging on reproduction and life-history traits in individual migratory birds, especially in small birds. Methods: We used long-term data of 85 tagged common swifts (Apus apus), a long-distance migratory bird, of a breeding colony in Germany to test whether carrying a geolocator or GPS logger once or repeatedly during nonbreeding season affected return rate, apparent survival, and parameters determining reproductive success. Additionally, we checked for individual differences in arrival date and breeding parameters when the same individuals were tagged and when they were not tagged in different years. Further, we calculated the individual repeatability in arrival at the breeding colony and date of egg laying in repeatedly tagged swifts. Results: Once and repeatedly tagged birds returned to the colony at a similar rate as non-logger birds and arrived earlier than non-logger birds. We found no effect of logger-type on return rate in logger birds. We detected no differences in apparent survival, time lag to clutch initiation, date of clutch initiation, clutch size, number of chicks and fledglings between logger and non-logger birds. We found neither an effect of loggers nor of logger-types on the arrival date and breeding parameter on individual-level. Arrival date was highly repeatable and date of clutch initiation was moderately repeatable within repeatedly tagged individuals.Source Type:Article362 65
