A novel approach to estimate glacier mass balance in the Tien Shan and Pamir based on transient snowline observations

Glaciers are recognised as an excellent proxy for climate change and their centennial massloss has accelerated during the past decades. The Central Asian mountain ranges Tien Shan and Pamir host over 25,000 glaciers that have been observed to respond heterogeneous to climate change. Glacier changes in the region have very important consequences on the water availability for the densely populated lowlands. Despite the significance and severity that climate change exerts on the Central Asian water towers, the glacier response is still poorly understood, hampering sound interpretations and predictions of future threats and opportunities. A significant data gap in the field measurement series from the mid-1990s to around 2010, limits the analysis of long-term trends. Despite the recent efforts to re-established the historical cryospheric monitoring network, continuous long-term glacier mass balance time series remain sparse for Central Asia. Thus, improved temporal and spatial coverage of glacier monitoring is essential. Remote sensing techniques are a powerful tool to study a large number of remotely located and unmeasured glaciers and provide a possibility to partly bridge the aforementioned deficit in data availability. However, the coarse temporal resolution of geodetic mass balance assessments is not suitable to improve the understanding of ongoing processes. This accentuates the indispensable need for improved and extended annual to seasonal observations of mass change of inaccessible and remote glaciers on a cost and labour effective basis as well as for a more elaborated and enhanced, process-orientated methodology. This work provides a combination of detailed in situ measurements and remote sensing based glacier mass change observation from local to regional scale. A multi-level strategy is applied to complement data from long-term glaciological surveys and remote sensing (snowline observations and geodetic mass balance measurements) with numerical modelling to obtain information at high temporal and spatial resolution for individual glaciers. Through modelling constrained with transient snowlines, annual mass balance time series for a large amount of glaciers located in the Tien Shan and Pamir were made available. Such mass balance estimates provide valuable baseline data for climate change assessments, runoff projection, hazard evaluation and enhance process understanding. A better understanding of the regional annual variability of glacier response to climate change in the Pamir and Tien Shan became possible based on the outcome of this thesis. In the presented thesis the results are discussed in detail, the weaknesses and strengths of the developed methodology are unfolded and the relevant perspective and future research outlined.Gletscher sind ausgezeichnete Indikatoren für den Klimawandel. Ihr langjähriger Massen- verlust hat sich in den letzten Jahrzehnten weltweit akzentuiert. Die zentralasiatischen Bergketten Tien Shan und Pamir beherbergen u¨ber 25’000 Gletscher. Studien zeigen, dass diese Gletscher heterogen auf den Klimawandel reagieren. Gletscherver¨anderungen in der Region haben wichtige Auswirkungen auf die Wasserverfügbarkeit für das dicht besiedelte Flachland. Trotz den bedeutenden Konsequenzen welche durch den Klimawandel auf diese regionalen Wasserspeicher ausgeübt wird, ist die Veränderung der Gletscher im Tien Shan und Pamir immer noch relativ unbekannt, was fundierte Interpretationen und Vorhersagen zukünftiger Gefahren und Chancen erschwert. Eine prägnante Datenlücke in den existierenden Messreihen von Mitte der 1990er Jahren bis ca. 2010 schränkt eine detaillierte Analyse langfristiger Entwicklungen weiter ein. Trotz der jüngsten Bemühungen, das historische Kryosphäremessnetz wieder herzustellen, bleiben kontinuierliche Langzeitmessungen für die Gletscher in Zentralasien limitiert. Eine verbesserte zeitliche und räumliche Abdeckung der Gletscherbeobachtungen ist daher unerlässlich. Fernerkundungstechniken sind gängige Methoden, um eine große Anzahl abgelegener und unerforschter Gletscher zu untersuchen. Mit solchen Methoden kann das Defizit an Datenverfügbarkeit der Region teilweise kompensiert werden. Die grobe zeitliche Auflösung der geodätischen Massenbilanzberechnungen und das somit limitierte Prozessverständnis unterstreichen jedoch den unabdingbaren Bedarf nach verbesserten und erweiterten jährlichen bis saisonalen Massenbilanzbeobachtungen. Ab- schätzungen auf ausgedehnter räumlicher Skala, sowie eine stärkere Prozess orientierte Forschung sind nötig. Die vorliegende Arbeit beschreibt eine Kombination aus detaillierten Feldmessungen und Fernerkundungsbeobachtungen der Gletschermassenänderung im Tien Shan und Pamir. Die angewandte Strategie basiert auf mehreren Ebenen aus lokalen bis regionalen Studien. Mit dieser Strategie werden Daten aus langzeit-glaziologischen Feldmessungen und aus der Fernerkundung (Schneelinienbeobachtungen, geodätische Massenbilanzmessungen) mit numerischen Modellierungen komplementieren. Dabei werden Informationen für ausgewählte Gletscher mit hoher zeitlicher und räumlicher Auflösung extrahiert. Durch das Modellieren mit wiederholten Schneelinienbeobachtungen, welche zur Kalibrierung verwendet werden, konnten jährliche Massenbilanzzeitreihen für eine große Anzahl von Gletschern im Studiengebiet berechnet werden. Solche grossräumigen und zeitlich hochaufgelösten Abschätzungen liefern wertvolle Grundlagen für detaillierte Studien über die Auswirkungen des Klimawandels, ermöglichen fundierte Abflussprojektionen und erlauben verbesserte Gefahrenanalysen. Basierend auf den Ergebnissen dieser Arbeit, wird ein besseres Verständnis der regionalen jährlichen Variabilität der Gletscherreaktionen auf den Klimawandel im Pamir und Tien Shan ermöglicht. In der hier vorgelegten Arbeit werden die Resultate im Detail diskutiert, die Schwächen und Stärken der entwickelten Methodik offengelegt und die relevanten Perspektiven abgefasst

A Xenopus laevis creatine kinase isozyme (CK-III/III) expressed preferentially in larval striated muscle: cDNA sequence, developmental expression and subcellular immunolocalization

A cDNA containing the nearly complete coding sequence of CK-III subunit of X. laevis was isolated, sequenced and further identified by comparing the tissue distribution of CK-III/III isozyme with that of its messenger. Comparison of CK-III deduced amino acid sequence with other CK sequences published reveals its close homology to M-CK subunits. Results using both cDNA probes and monoclonal antibodies specific for CK-III subunits indicate that the appearance and the accumulation of CK-III occur in parallel with myoblast differentiation. Moreover, subcellular immuno-histolocalization shows that CK-III/III isozyme is especially concentrated on larval myofibres at the level of A-band

Mass balance observations and reconstruction for Batysh Sook Glacier, Tien Shan, from 2004 to 2016

In this study we present an analysis of measured annual mass balances for the period 2011 to 2016 and a reconstruction of seasonal mass balances from 2004 to 2010 for Batysh Sook Glacier located in the Kyrgyz Tien Shan. Conventional methods and a model-based extrapolation of the point measurements were used to obtain glacier- wide mass balances and to analyze glaciological measurements. Especially at the beginning of the re-established glacier mass balance monitoring program, deviations between the different methods were significant, having a range of 0.40 m w.e. a− 1. With the improvement of the measurement network in later years, the results of the different extrapolation methods showed better agreement (range of 0.10 to 0.22 m w.e. a− 1). For 2011 to 2016, the profile method revealed a mass loss of − 0.41 ± 28 m w.e. a− 1. The contour line method yielded a negative mean mass balance of − 0.34 ± 20 m w.e a− 1, whereas the model-based extrapolation clearly resulted in the most negative value of − 0.43 ± 16 m w.e. a− 1 for the same period.The same distributed accumulation and temperature index melt model used to extrapolate point measurements from 2011 to 2016 was applied in order to reconstruct the mass balance from 2004 to 2010. The model was driven by daily air temperature and precipitation data from a nearby meteorological station and the model parameters were calibrated with in-situ measurements of annual mass balances collected from 2011 to 2016. Winter accumulation measurements taken in May 2014 were used for calibration purposes and to deduce snow distribution patterns. Subseasonal model performance was validated based on the snow cover depletion pattern observed on satellite images during the summer months from 2004 to 2016. For Batysh Sook Glacier an average annual mass balance of − 0.39 ± 0.26 m w.e. a− 1 was found for the period 2003/04 to 2015/16

Mathematical foundations of the non-Hermitian skin effect

We study the skin effect in a one-dimensional system of finitely many subwavelength resonators with a non-Hermitian imaginary gauge potential. Using Toeplitz matrix theory, we prove the condensation of bulk eigenmodes at one of the edges of the system. By introducing a generalised (complex) Brillouin zone, we can compute spectral bands of the associated infinitely periodic structure and prove that this is the limit of the spectra of the finite structures with arbitrarily large size. Finally, we contrast the non-Hermitian systems with imaginary gauge potentials considered here with systems where the non-Hermiticity arises due to complex material parameters, showing that the two systems are fundamentally distinct.Comment: 28 pages, 11 figure

Specific targeting of human caspases using designed ankyrin repeat proteins

Caspases play important roles in cell death, differentiation, and proliferation. Due to their high homology, especially of the active site, specific targeting of a particular caspase using substrate analogues is very difficult. Although commercially available small molecules based on peptides are lacking high specificity due to overlapping cleavage motives between different caspases, they are often used as specific tools. We have selected designed ankyrin repeat proteins (DARPins) against human caspases 1-9 and identified high-affinity binders for the targeted caspases, except for caspase 4. Besides previously reported caspase-specific DARPins, we generated novel DARPins (D1.73, D5.15, D6.11, D8.1, D8.4, and D9.2) and confirmed specificity for caspases 1, 5, 6, and 8 using a subset of caspase family members. In addition, we solved the crystal structure of caspase 8 in complex with DARPin D8.4. This binder interacts with non-conserved residues on the large subunit, thereby explaining its specificity. Structural analysis of this and other previously published crystal structures of caspase/DARPin complexes depicts two general binding areas either involving active site forming loops or a surface area laterally at the large subunit of the enzyme. Both surface areas involve non-conserved surface residues of caspase

The Non-Hermitian Skin Effect With Three-Dimensional Long-Range Coupling

We study the non-Hermitian skin effect in a three-dimensional system of finitely many subwavelength resonators with an imaginary gauge potential. We introduce a discrete approximation of the eigenmodes and eigenfrequencies of the system in terms of the eigenvectors and eigenvalues of the so-called gauge capacitance matrix $\mathcal{C}_N^\gamma$, which is a dense matrix due to long-range interactions in the system. Based on translational invariance of this matrix and the decay of its off-diagonal entries, we prove the condensation of the eigenmodes at one edge of the structure by showing the exponential decay of its pseudo-eigenvectors. In particular, we consider a range-k approximation to keep the long-range interaction to a certain extent, thus obtaining a k-banded gauge capacitance matrix $\mathcal{C}_{N,k}^\gamma$ . Using techniques for Toeplitz matrices and operators, we establish the exponential decay of the pseudo-eigenvectors of $\mathcal{C}_{N,k}^\gamma$ and demonstrate that they approximate those of the gauge capacitance matrix $\mathcal{C}_N^\gamma$ well. Our results are numerically verified. In particular, we show that long-range interactions affect only the first eigenmodes in the system. As a result, a tridiagonal approximation of the gauge capacitance matrix, similar to the nearest-neighbour approximation in quantum mechanics, provides a good approximation for the higher modes. Moreover, we also illustrate numerically the behaviour of the eigenmodes and the stability of the non-Hermitian skin effect with respect to disorder in a variety of three-dimensional structures.Comment: 32 pages, 11 figure

Predictor variables for half marathon race time in recreational female runners

Anthropometric and training variables were related to half-marathon race time in recreational female runners. Skin-fold thicknesses at various upper body locations were related to training intensity. High running speed in training appears to be important for fast half-marathon race times and may reduce upper body skin-fold thicknesses in recreational female half marathoners