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Transverse energy flow in an optical Skyrmionic Hopfion
No full textThe energy flow of light represents a natural way of investigating complex light fields with respect to their applicability. With the generation of a three-dimensional Skyrmionic Hopfion structure in light, which is a topological 3D field configuration with particle-like nature, we paved the way to employ optical, topological constructs. In this work, we present an analysis of the transverse energy flow in the optical Skyrmionic Hopfion, showing the transfer of the topological properties to the mechanical attributes such as the optical angular momentum (OAM). Our findings thus prepare topological structures to be applied in optical traps and data storage or communication
Was ist ästhetische Wertschätzung?:Das Dissertationsprojekt »Ästhetische Wertschätzung und Literatur«
No full textZiel des Dissertationsprojekts »Ästhetische Wertschätzung und Literatur« ist es, mit einer Explikation auf die Frage ›Was ist ästhetische Wertschätzung?‹ zu antworten. Hierzu werden neuere Theorien der ›analytischen‹ philosophischen Ästhetik zu den Themen ›ästhetischer Wert‹, ›ästhetische Erfahrung‹ und ›ästhetische Wertschätzung‹ diskutiert
Was ist Literatur wert?:Geltungskulturen und plurale Rechtfertigungsordnungen zeitgenössischer Literaturkritik
No full textUnter welchen Bedingungen erlangen Wissensansprüche Geltung oder nicht? Dieser Frage geht das interdisziplinäre Forschungsnetzwerk »Wissensgeltung« an der Universität Heidelberg nach. Literaturtheoretisch relevante Aspekte der Forschungen des Netzwerks werden hier anhand einer Studie zur zeitgenössischen Literaturkritik unter der Frage »Was ist Literatur wert?« vorgestellt
»What matters?«:Schlüsselstellen in Theorie und Praxis
No full textInterpretationen verfahren bei längeren literarischen Texten gekonnt selektiv: Sie nehmen bestimmte Stellen wichtig und vernachlässigen andere. Wie verfährt dieser Selektionsprozess und wie müsste eine Interpretationstheorie konzipiert sein, die die Praxis der gekonnten Aufmerksamkeitsfokussierung angemessen berücksichtigt
Pseudoprogression prediction in high grade primary CNS tumors by use of radiomics
No full textOur aim is to define the capabilities of radiomics and machine learning in predicting pseudoprogression development from pre-treatment MR images in a patient cohort diagnosed with high grade gliomas. In this retrospective analysis, we analysed 131 patients with high grade gliomas. Segmentation of the contrast enhancing parts of the tumor before administration of radio-chemotherapy was semi-automatically performed using the 3D Slicer open-source software platform (version 4.10) on T1 post contrast MR images. Imaging data was split into training data, test data and an independent validation sample at random. We extracted a total of 107 radiomic features by hand-delineated regions of interest (ROI). Feature selection and model construction were performed using Generalized Boosted Regression Models (GBM). 131 patients were included, of which 64 patients had a histopathologically proven progressive disease and 67 were diagnosed with mixed or pure pseudoprogression after initial treatment. Our Radiomics approach is able to predict the occurrence of pseudoprogression with an AUC, mean sensitivity, mean specificity and mean accuracy of 91.49% [86.27%, 95.89%], 79.92% [73.08%, 87.55%], 88.61% [85.19%, 94.44%] and 84.35% [80.19%, 90.57%] in the full development group, 78.51% [75.27%, 82.46%], 66.26% [57.95%, 73.02%], 78.31% [70.48%, 84.19%] and 72.40% [68.06%, 76.85%] in the testing group and finally 72.87% [70.18%, 76.28%], 71.75% [62.29%, 75.00%], 80.00% [69.23%, 84.62%] and 76.04% [69.90%, 80.00%] in the independent validation sample, respectively. Our results indicate that radiomics is a promising tool to predict pseudo-progression, thus potentially allowing to reduce the use of biopsies and invasive histopathology
Referenz im bilingualen deutsch-polnischen Erstspracherwerb
No full textDie vorliegende Dissertation beschäftigt sich mit dem Referenzerwerb bei einem simultan bilingualen deutsch-polnischen Kind im Alter von 1;3 bis 4;0. Im Kern der Studie stehen der Erwerb und der Gebrauch von sprachspezifischen Referenzmitteln. Die Entwicklung beider Referenzsysteme wurde im Zusammenhang mit dem Aufbau der pragmatischen Kategorien Spezifizität und Bekanntheit untersucht. Da die beiden Referenzsysteme zahlreiche Unterschiede in Bezug auf die Distribution von Referenzmitteln aufweisen, wurde zudem überprüft, ob es im bilingualen deutsch-polnischen Referenzerwerb zu cross-linguistischen Einflüssen kommt. Zur Bearbeitung dieser Forschungsfrage wurde die Sprachproduktion von drei monolingual aufwachsenden polnischsprachigen Kindern im Alter zwischen 1;7 und 3;2 untersucht. Die analysierten Korpora bestehen aus Video- und Audioaufnahmen von spontanen Alltagsinteraktionen. Die durchgeführten Analysen basieren sowohl auf quantitativen als auch auf qualitativen Methoden
Refixation of a Large Osteochondral Fragment with Magnesium Compression Screws—A Case Report
No full textIntroduction: Osteochondrosis dissecans (OCD) is a disease affecting the subchondral bone and the overlying articular cartilage. The etiology is most likely a combination of biological and mechanical factors. The incidence is highest in children >12 years old and it predominantly affects the knee. In high-grade OCD lesions, free osteochondral fragments usually are refixed via titanium screws or biodegradable screws or pins. In this case, headless compression screws made from magnesium were used for refixation. Case report: A thirteen-year-old female patient with a two-year history of knee pain was diagnosed with an OCD lesion of the medial femoral condyle. After initial conservative treatment, displacement of the osteochondral fragment occurred. Refixation was performed using two headless magnesium compression screws. At the 6 months follow up, the patient was pain free, and the fragment showed progressive healing while the implants were biodegrading. Discussion: Existing implants for refixation of OCD lesions either require subsequent removal or show less stability and possible inflammatory reactions. The new generation of magnesium screws used in this case did not lead to a gas release, as described for previous magnesium implants, while maintaining stability during continuous biodegradation. Conclusions: The data available to date on magnesium implants for the treatment of OCD are promising. However, the evidence on the magnesium implants in refixation surgery of OCD lesions is still limited. Further research needs to be conducted to provide data on outcomes and possible complications
Saccadic suppression in schizophrenia
No full textAbout 40% of schizophrenia patients report discrete visual disturbances which could occur if saccadic suppression, the decrease of visual sensitivity around saccade onset, is impaired. Two mechanisms contribute to saccadic suppression: efference copy processing and backwards masking. Both are reportedly altered in schizophrenia. However, saccadic suppression has not been investigated in schizophrenia. 17 schizophrenia patients and 18 healthy controls performed a saccadic suppression task using a Gabor stimulus with individually adjusted contrast, which was presented within an interval 300 ms around saccade onset. Visual disturbance scores were higher in patients than controls, but saccadic suppression strength and time course were similar in both groups with lower saccadic suppression rates being similarly related to smaller saccade amplitudes. Saccade amplitudes in the saccadic suppression task were reduced in patients, in contrast to unaltered amplitudes during a saccade control task. Notably, smaller saccade amplitudes were related to higher visual disturbances scores in patients. Saccadic suppression performance was unrelated to symptom expression and antipsychotic medication. Unaltered saccadic suppression in patients suggests sufficiently intact efference copy processing and backward masking as required for this task. Instead, visual disturbances in patients may be related to restricted saccadic amplitudes arising from cognitive load while completing a task
Shaping light in 3d space by counter-propagation
No full textWe extend the established transverse customization of light, in particular, amplitude, phase, and polarization modulation of the light field, and its analysis by the third, longitudinal spatial dimension, enabling the visualization of longitudinal structures in sub-wavelength (nm) range. To achieve this high-precision and three-dimensional beam shaping and detection, we propose an approach based on precise variation of indices in the superposition of higher-order Laguerre-Gaussian beams and cylindrical vector beams in a counter-propagation scheme. The superposition is analyzed experimentally by digital, holographic counter-propagation leading to stable, reversible and precise scanning of the light volume. Our findings show tailored amplitude, phase and polarization structures, adaptable in 3D space by mode indices, including sub-wavelength structural changes upon propagation, which will be of interest for advanced material machining and optical trapping
Short Sampling Periods: A New Setup to Evaluate the Change in the Chemical Composition of Fog at High Time Resolution
No full textThis study used a water volume-based sampling method in combination with an active fog collector (modified Caltech design) to collect fog water samples during three intensive operation periods at two mountainous study sites in Taiwan. The new setup employed a sample-volume controlled system that dosed the fog water into 10 ml aliquots, which were then collected with a commercial laboratory auto-sampler. We collected fog water samples about 10 times more frequently (median sampling period 3 minutes and 45 seconds) than with traditional sampling schemes. Notably, up to over 200 samples were collected within a single fog event lasting 13 hours. The results showed that the intra-event variabilities of pH (up to over 2 units), conductivity (range almost 1000 μS cm^–1), and ion concentrations were generally higher than the inter-event variability. The variabilities exhibited particularly fast changes during phases of fog onset and dissolution; in contrast, the centers of the passing clouds at our mountain research sites were rather homogeneous. Overall, our new method showed a marked improvement in sampling speed over traditional methods