Fontanes Fauna

Die Dissertation entwickelt eine Poetik der Tiere, die eng an zentrale Themen der fontaneschen Poetologie rückgebunden ist. Sie nimmt dabei sowohl das ganze erzählerische Werk Theodor Fontanes in den Blick als auch die gesamte Tierwelt, in der großen Bandbreite, in der sie in den Texten als lebendige Wesen der Diegese, als kulturelle Artefakte oder als Materialgeber zur Figurencharakterisierung repräsentiert ist. In größeren Bögen wie auch in Detailanalysen erschließt die Arbeit kulturhistorische Kontexte zu Tieren, setzt Fontanes Tierdarstellung in Bezug zu zeitgenössischem Wissen und verbindet diese mit programmatischen Realismus-Diskussionen der Zeit. Michael de Zan studierte Germanistik und katholische Theologie an der Ludwig-Maximilians-Universität München, wo er 2020 mit der vorliegenden Dissertation promoviert wurde. Er ist wissenschaftlicher Mitarbeiter am Lehrstuhl für Neuere deutsche Literaturwissenschaft an der LMU München und seit 2014 als freiberuflicher IT-Berater tätig

Prolonged Illness Among Subsistence Agricultural Households in Rural Mozambique: Coping Strategies and Policy Levers

Subsistence agriculturalists are highly economically vulnerable, and generally lack access to resources that may help strengthen their livelihoods. Health is a well-established form of human capital that is also one of the biggest assets for subsistence agricultural households. Therefore, any instance in which this form of capital is threatened has potential consequences for livelihood sustainability. This dissertation examined prolonged illness among subsistence agricultural households in rural Mozambique. Prolonged illness can diminish household labor supply, a vital input for subsistence agriculture. My research sought to: 1) identify potential agricultural and land use coping strategies used by unhealthy subsistence agricultural households, and examine whether or not changes in health status induce land cover change; 2) isolate health's effect on a known agricultural land use decision--fallowing--to more rigorously examine the negative health-land relationship; and 3) examine how a policy lever such as access to health services could be more equitably distributed to subsistence agricultural households. I found that unhealthy households were more likely to alter household agricultural land use decisions to cope with prolonged illness, and that they were different than their healthier counterparts in key agricultural ways that may threaten their livelihoods and contribute to food insecurity. While changes in health status do spur land use and land cover change, the relationship is challenging to detect with the current offering of satellite imagery. Additionally, access to health clinics represents a policy lever aimed at supporting unhealthy citizens to maintain their livelihoods. I found that the way "need" is defined in terms of access matters and that access to a high-quality service such as antiretroviral therapy could be more equitably distributed to vulnerable segments of society. This research demonstrates the value of using mixed methods, as the combination of qualitative, econometric, and geospatial methods, to provide a more holistic understanding of the micro-level effects of prolonged illness among subsistence agricultural households in rural Mozambique

Toward Operational Compensation of Ionospheric Effects in SAR Interferograms: The Split-Spectrum Method

The differential ionospheric path delay is a major error source in L-band interferograms. It is superimposed to topography and ground deformation signals, hindering the measurement of geophysical processes. In this paper, we proceed toward the realization of an operational processor to compensate the ionospheric effects in interferograms. The processor should be robust and accurate to meet the scientific requirements for the measurement of geophysical processes, and it should be applicable on a global scale. An implementation of the split-spectrum method, which will be one element of the processor, is presented in detail, and its performance is analyzed. The method is based on the dispersive nature of the ionosphere and separates the ionospheric component of the interferometric phase from the nondispersive component related to topography, ground motion, and tropospheric path delay. We tested the method using various Advanced Land Observing Satellite Phased-Array type L-band synthetic aperture radar interferometric pairs with different characteristics: high to low coherence, moving and nonmoving terrains, with and without topography, and different ionosphere states. Ionospheric errors of almost 1 m have been corrected to a centimeter or a millimeter level. The results show how the method is able to systematically compensate the ionospheric phase in interferograms, with the expected accuracy, and can therefore be a valid element of the operational processor

Multiplexed Monitoring of Neurochemicals via Electrografting- Enabled Site-Selective Functionalization of Aptamers on Field-Effect Transistors

Neurochemical corelease has received much attention in understanding brain activity and cognition. Despite many attempts, the multiplexed monitoring of coreleased neurochemicals with spatiotemporal precision and minimal crosstalk using existing methods remains challenging. Here, we report a soft neural probe for multiplexed neurochemical monitoring via the electrografting-assisted site-selective functionalization of aptamers on graphene field-effect transistors (G-FETs). The neural probes possess excellent flexibility, ultralight mass (28 mg), and a nearly cellular-scale dimension of 50 μm × 50 μm for each G-FET. As a demonstration, we show that G-FETs with electrochemically grafted molecular linkers (−COOH or −NH2) and specific aptamers can be used to monitor serotonin and dopamine with high sensitivity (limit of detection: 10 pM) and selectivity (dopamine sensor \u3e22-fold over norepinephrine; serotonin sensor \u3e17-fold over dopamine). In addition, we demonstrate the feasibility of the simultaneous monitoring of dopamine and serotonin in a single neural probe with minimal crosstalk and interferences in phosphate-buffered saline, artificial cerebrospinal fluid, and harvested mouse brain tissues. The stability studies show that multiplexed neural probes maintain the capability for simultaneously monitoring dopamine and serotonin with minimal crosstalk after incubating in rat cerebrospinal fluid for 96 h, although a reduced sensor response at high concentrations is observed. Ex vivo studies in harvested mice brains suggest potential applications in monitoring the evoked release of dopamine and serotonin. The developed multiplexed detection methodology can also be adapted for monitoring other neurochemicals, such as metabolites and neuropeptides, by simply replacing the aptamers functionalized on the G-FETs

Overexpression of eIF-5A2 in mice causes accelerated organismal aging by increasing chromosome instability

<p>Abstract</p> <p>Background</p> <p>Amplification of 3q26 is one of the most frequent genetic alterations in many human malignancies. Recently, we isolated a novel oncogene <it>eIF-5A2 </it>within the 3q26 region. Functional study has demonstrated the oncogenic role of <it>eIF-5A2 </it>in the initiation and progression of human cancers. In the present study, we aim to investigate the physiological and pathological effect of <it>eIF-5A2 </it>in an <it>eIF-5A2 </it>transgenic mouse model.</p> <p>Methods</p> <p>An <it>eIF-5A2 </it>transgenic mouse model was generated using human <it>eIF-5A2 </it>cDNA. The <it>eIF-5A2 </it>transgenic mice were characterized by histological and immunohistochemistry analyses. The aging phenotypes were further characterized by wound healing, bone X-ray imaging and calcification analysis. Mouse embryo fibroblasts (MEF) were isolated to further investigate molecular mechanism of <it>eIF-5A2 </it>in aging.</p> <p>Results</p> <p>Instead of resulting in spontaneous tumor formation, overexpression of eIF-5A2 accelerated the aging process in adult transgenic mice. This included decreased growth rate and body weight, shortened life span, kyphosis, osteoporosis, delay of wound healing and ossification. Investigation of the correlation between cellular senescence and aging showed that cellular senescence is not required for the aging phenotypes in <it>eIF-5A2 </it>mice. Interestingly, we found that activation of <it>eIF-5A2 </it>repressed p19 level and therefore destabilized p53 in transgenic mouse embryo fibroblast (MEF) cells. This subsequently allowed for the accumulation of chromosomal instability, such as errors in cell dividing during metaphase and anaphase. Additionally, a significantly increase in number of aneuploidy cells (<it>p </it>< 0.05) resulted from an increase in the incidences of misaligned and lagging chromosomal materials, anaphase bridges, and micronuclei in the transgenic mice.</p> <p>Conclusion</p> <p>These observations suggest that <it>eIF-5A2 </it>mouse models could accelerate organismal aging by increasing chromosome instability.</p

Large Scale Interferometric Processing of Sentinel-1 Data over the Atacama Desert - a Contribution to the TecVolSA Project

The project TecVolSA (Tectonics and Volcanoes in South America) aims at developing an intelligent Earth Observation (EO) data processing system for monitoring the earthquake cycle and volcanic events in South America. The Remote Sensing Technology Institute of DLR participates to this project together with GFZ (German Research Centre for Geosciences). The project is partially financed by Helmholtz. So far we have processed about 40 Sentinel-1 slices covering the Atacama Desert with mixed Permanent Scatterer and Distributed Scatterer (PS/DS) techniques. The area is very dry and the spatio-temporal coverage is excellent. Tropospheric correction have been applied using ECMWF ERA5 data, hence improving the performance in observing both topography related and large scale deformation signals. The current results reveal, as expected, plenty of interesting signals to be interpreted (see attached figure for an overview of the velocity field). Preliminary GPS cross-validation, thanks to data freely available from the Geodetic Nevada Laboratory, confirm that the InSAR relative error in the estimated velocities is in the order of 1 mm/yr at large scale (>100 km) and confirms the large scale signal related to the subduction of the Nazca plate (see attached figure). More GNSS validation will be possible with additional GPS stations. The challenge of the project is the separation of different contributions to the InSAR measurements: apart from the tectonic effects, there are contributions coming from volcanic unrest, atmospheric delays, moisture effects, snow, flank instability (likely downhill creep or solifluction related to permafrost, see attached figure), salt lake growth, mining, and likely more. We are dealing with this complexity with a diversity of tools: physical modeling and statistical analysis, deep neural networks, and expert knowledge. GFZ contributes process knowledge, historic seismic data, in-situ motion measurements and observations and 4D geophysical modelling codes for producing a diverse database for the training of neural networks in order to autonomously discover significant events in noisy data. We tackle the problem as a semi-supervised multi-class classification approach where the labeling of the known deformation phenomena is provided by GFZ. Signals for which the source of deformation is unknown are identified and clustered automatically using advanced unsupervised machine-learning techniques. Therefore, we leverage from the advantages of both supervised and unsupervised learning and improve the accuracy for detection and classification of different deformation sources. The networks and AI-based methods are developed at DLR. This new approach (InSAR + Artificial Intelligence) should be able to process the massive data stream of the Copernicus Sentinel-1 SAR mission. South America was selected because manifold geophysical signals can be expected there in short time scales and plenty of in-situ data are available. This project will complement the current model-based geophysical research by a data-driven AI-based approach. Training and applying this intelligent system shall improve our understanding of geophysical processes related to natural and anthropogenic hazards. At a later stage the system shall be scalable to global processing capacity. Future developments on the InSAR processing will include ionospheric corrections based on split-spectrum and mosaicking of the velocity and displacement series. Some issues with the L1 processor are hindering the deployment of the split-spectrum technique. Stacks from the ascending geometry are already being processed and will help the geophysical interpretation

The Tandem-L Mission Proposal: Monitoring Earth’s Dynamics with High Resolution SAR Interferometry

Tandem-L is a proposal for an innovative interferometric and polarimetric radar mission that enables the systematic monitoring of dynamic processes on the Earth surface. Important mission objectives are global forest height and biomass inventories, large scale measurements of millimetric displacements due to tectonic shifts, and systematic observations of glacier movements. The innovative mission concept and the high data acquisition capacity of Tandem-L provide a unique data source to observe, analyze and quantify the dynamics of a wide range of mutually interacting processes in the bio-, litho-, hydro- and cryosphere. By this, Tandem-L will be an essential step to advance our understanding of the Earth system and its intricate dynamics. This paper provides an overview of the Tandem-L mission concept and its main application areas. Performance predictions show the great potential of Tandem-L to acquire a wide range of bio- and geophysical parameters with high accuracy on a global scale. Innovative aspects like the employment of advanced digital beamforming techniques to improve performance and coverage are discussed in detail

Polζ ablation in B cells impairs the germinal center reaction, class switch recombination, DNA break repair, and genome stability

Polζ is an error-prone DNA polymerase that is critical for embryonic development and maintenance of genome stability. To analyze its suggested role in somatic hypermutation (SHM) and possible contribution to DNA double-strand break (DSB) repair in class switch recombination (CSR), we ablated Rev3, the catalytic subunit of Polζ, selectively in mature B cells in vivo. The frequency of somatic mutation was reduced in the mutant cells but the pattern of SHM was unaffected. Rev3-deficient B cells also exhibited pronounced chromosomal instability and impaired proliferation capacity. Although the data thus argue against a direct role of Polζ in SHM, Polζ deficiency directly interfered with CSR in that activated Rev3-deficient B cells exhibited a reduced efficiency of CSR and an increased frequency of DNA breaks in the immunoglobulin H locus. Based on our results, we suggest a nonredundant role of Polζ in DNA DSB repair through nonhomologous end joining