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Magmatic-hydrothermal fluids are responsible for numerous mineralization types, including porphyry copper and granite related tin-tungsten (Sn-W) deposits. Ore formation is dependent on various factors, including, the pressure and temperature regime of the intrusions, the chemical composition of the magma and hydrothermal fluids, and fluid rock interaction during the ascent. Fluid inclusions have potential to provide direct information on the temperature, salinity, pressure and chemical composition of fluids responsible for ore formation. Numerical modeling allows the parametrization of pluton features that cannot be analyzed directly via geological observations.
Microthermometry of fluid inclusions from the Zinnwald Sn-W deposit, Erzgebirge, Germany / Czech Republic, provide evidence that the greisen mineralization is associated with a low salinity (2-10 wt.% NaCl eq.) fluid with homogenization temperatures between 350°C and 400°C. Quartzes from numerous veins are host to inclusions with the same temperatures and salinities, whereas cassiterite- and wolframite-hosted assemblages with slightly lower temperatures (around 350°C) and higher salinities (ca. 15 wt. NaCl eq.). Further, rare quartz samples contained boiling assemblages consisting of coexisting brine and vapor phases. The formation of ore minerals within the greisen is driven by invasive fluid-rock interaction, resulting in the loss of complexing agents (Cl-) leading to precipitation of cassiterite. The fluid inclusion record in the veins suggests boiling as the main reason for cassiterite and wolframite mineralization. Ore and coexisting gangue minerals hosted different types of fluid inclusions where the beginning boiling processes are solely preserved by the ore minerals emphasizing the importance of microthermometry in ore minerals. Further, the study indicates that boiling as a precipitation mechanism can only occur in mineralization related to shallow intrusions whereas deeper plutons prevent the fluid from boiling and can therefore form tungsten mineralization in the distal regions.
The tin mineralization in the Hämmerlein deposit, Erzgebirge, Germany, occurs within a skarn horizon and the underlying schist. Cassiterite within the skarn contains highly saline (30-50 wt% NaCl eq.) fluid inclusions, with homogenization temperatures up to 500°C, whereas cassiterites from the schist and additional greisen samples contain inclusions of lower salinity (~5 wt% NaCl eq.) and temperature (between 350 and 400°C). Inclusions in the gangue minerals (quartz, fluorite) preserve homogenization temperatures below 350°C and sphalerite showed the lowest homogenization temperatures (ca. 200°C) whereby all minerals (cassiterite from schist and greisen, gangue minerals and sphalerite) show similar salinity ranges (2-5 wt% NaCl eq.). Similar trace element contents and linear trends in the chemistry of the inclusions suggest a common source fluid. The inclusion record in the Hämmerlein deposit documents an early exsolution of hot brines from the underlying granite which is responsible for the mineralization hosted by the skarn. Cassiterites in schist and greisen are mainly forming due to fluid-rock interaction at lower temperatures. The low temperature inclusions documented in the sphalerite mineralization as well as their generally low trace element composition in comparison to the other minerals suggests that their formation was induced by mixing with meteoric fluids.
Numerical simulations of magma chambers and overlying copper distribution document the importance of incremental growth by sills. We analyzed the cooling behavior at variable injection intervals as well as sill thicknesses. The models suggest that magma accumulation requires volumetric injection rates of at least 4 x 10-4 km³/y. These injection rates are further needed to form a stable magmatic-hydrothermal fluid plume above the magma chamber to ensure a constant copper precipitation and enrichment within a confined location in order to form high-grade ore shells within a narrow geological timeframe between 50 and 100 kyrs as suggested for porphyry copper deposits. The highest copper enrichment can be found in regions with steep temperature gradients, typical of regions where the magmatic-hydrothermal fluid meets the cooler ambient fluids.
Das Preußische Erbrecht in der Judikatur des Berliner Obertribunals in den Jahren 1836 bis 1865
(2019)
Die Dissertation befasst sich mit dem Allgemeinen Preußischen Landrecht von 1794 und der hierzu ergangenen Rechtsprechung des Berliner Obertribunals. Im Fokus der Untersuchung stehen die erbrechtlichen Regelungen des Landrechts und deren Anwendung sowie Auslegung in der Judikatur des höchsten preußischen Gerichts. Der Forschungsgegenstand ergibt sich aus dem im Landrecht kodifizierten speziellen Gesetzesverständnisses. Nach diesem sollte die Gesetzesauslegung durch die Rechtsprechung auf ein Minimum, nämlich die Auslegung allein anhand des Wortlauts der Regelung reduziert werden, um dem absolutistischen Regierungsanspruch der preußischen Monarchen, namentlich Friedrich des Großen, hinreichend Rechnung zu tragen. In diesem Kontext wird der Frage nachgegangen, inwieweit das preußische Obertribunal das im Landrecht statuierte „Auslegungsverbot“ beachtet hat und in welchen Fällen sich das Gericht von der Vorgabe emanzipierte und weitere Auslegungsmethoden anwendete und sich so eine unabhängige Rechtsprechung entwickeln konnte.
Die Arbeit gliedert sich in drei Hauptabschnitte. Im Anschluss an die Einleitung, in der zunächst die rechtshistorische Bedeutung des Landrechts und des Erbrechts sowie der Untersuchungsgegenstand umrissen werden, folgt die Darstellung der Entstehungsgeschichte des Landrechts und des Berliner Obertribunals.
Hieran schließt sich in einem dritten Abschnitt eine Analyse der erbrechtlichen Vorschriften des Landrechts an. In dieser wird auf die Entstehungsgeschichte der verschiedenen erbrechtlichen Institute wie beispielsweise der gesetzlichen und gewillkürten Erbfolge, dem Pflichtteilsrecht etc., unter Berücksichtigung des zeitgenössischen wissenschaftlichen Diskurses eingegangen.
Im vierten Abschnitt geht es um die Judikate des Berliner Obertribunals aus den Jahren 1836-1865 in denen die zuvor dargestellten erbrechtlichen Regelungen entscheidungserheblich waren. Dabei wird der Forschungsfrage, inwieweit das Obertribunal das im Landrecht statuierte Auslegungsverbot beachtet hat und in welchen Fällen es von diesem abwich bzw. weitere Auslegungsmethoden anwendete, konkret nachgegangen wird. Insgesamt werden 26 Entscheidungen des Obertribunals unter dem Aspekt der Auslegungspraxis, der Kontinuität und der Beschleunigung der Rechtsprechung analysiert und ausgewertet.
Since half a century, cytometry has been a major scientific discipline in the field of cytomics - the study of system’s biology at single cell level. It enables the investigation of physiological processes, functional characteristics and rare events with proteins by analysing multiple parameters on an individual cell basis. In the last decade, mass cytometry has been established which increased the parallel measurement to up to 50 proteins. This has shifted the analysis strategy from conventional consecutive manual gates towards multi-dimensional data processing. Novel algorithms have been developed to tackle these high-dimensional protein combinations in the data. They are mainly based on clustering or non-linear dimension reduction techniques, or both, often combined with an upstream downsampling procedure. However, these tools have obstacles either in comprehensible interpretability, reproducibility, computational complexity or in comparability between samples and groups.
To address this bottleneck, a reproducible, semi-automated cytometric data mining workflow PRI (pattern recognition of immune cells) is proposed which combines three main steps: i) data preparation and storage; ii) bin-based combinatorial variable engineering of three protein markers, the so called triploTs, and subsequent sectioning of these triploTs in four parts; and iii) deployment of a data-driven supervised learning algorithm, the cross-validated elastic-net regularized logistic regression, with these triploT sections as input variables. As a result, the selected variables from the models are ranked by their prevalence, which potentially have discriminative value. The purpose is to significantly facilitate the identification of meaningful subpopulations, which are most distinguish between two groups. The proposed workflow PRI is exemplified by a recently published public mass cytometry data set. The authors found a T cell subpopulation which is discriminative between effective and ineffective treatment of breast carcinomas in mice. With PRI, that subpopulation was not only validated, but was further narrowed down as a particular Th1 cell population. Moreover, additional insights of combinatorial protein expressions are revealed in a traceable manner. An essential element in the workflow is the reproducible variable engineering. These variables serve as basis for a clearly interpretable visualization, for a structured variable exploration and as input layers in neural network constructs.
PRI facilitates the determination of marker levels in a semi-continuous manner. Jointly with the combinatorial display, it allows a straightforward observation of correlating patterns, and thus, the dominant expressed markers and cell hierarchies. Furthermore, it enables the identification and complex characterization of discriminating subpopulations due to its reproducible and pseudo-multi-parametric pattern presentation. This endorses its applicability as a tool for unbiased investigations on cell subsets within multi-dimensional cytometric data sets.
Medical imaging plays an important role in disease diagnosis, treatment planning, and clinical monitoring. One of the major challenges in medical image analysis is imbalanced training data, in which the class of interest is much rarer than the other classes. Canonical machine learning algorithms suppose that the number of samples from different classes in the training dataset is roughly similar or balance. Training a machine learning model on an imbalanced dataset can introduce unique challenges to the learning problem.
A model learned from imbalanced training data is biased towards the high-frequency samples. The predicted results of such networks have low sensitivity and high precision. In medical applications, the cost of misclassification of the minority class could be more than the cost of misclassification of the majority class. For example, the risk of not detecting a tumor could be much higher than referring to a healthy subject to a doctor. The current Ph.D. thesis introduces several deep learning-based approaches for handling class imbalanced problems for learning multi-task such as disease classification and semantic segmentation.
At the data-level, the objective is to balance the data distribution through re-sampling the data space: we propose novel approaches to correct internal bias towards fewer frequency samples. These approaches include patient-wise batch sampling, complimentary labels, supervised and unsupervised minority oversampling using generative adversarial networks for all.
On the other hand, at algorithm-level, we modify the learning algorithm to alleviate the bias towards majority classes. In this regard, we propose different generative adversarial networks for cost-sensitive learning, ensemble learning, and mutual learning to deal with highly imbalanced imaging data.
We show evidence that the proposed approaches are applicable to different types of medical images of varied sizes on different applications of routine clinical tasks, such as disease classification and semantic segmentation. Our various implemented algorithms have shown outstanding results on different medical imaging challenges.
Light-switchable proteins are being used increasingly to understand and manipulate complex molecular systems. The success of this approach has fueled the development of tailored photo-switchable proteins, to enable targeted molecular events to be studied using light. The development of novel photo-switchable tools has to date largely relied on rational design. Complementing this approach with directed evolution would be expected to facilitate these efforts. Directed evolution, however, has been relatively infrequently used to develop photo-switchable proteins due to the challenge presented by high-throughput evaluation of switchable protein activity. This thesis describes the development of two genetic circuits that can be used to evaluate libraries of switchable proteins, enabling optimization of both the on- and off-states. A screening system is described, which permits detection of DNA-binding activity based on conditional expression of a fluorescent protein. In addition, a tunable selection system is presented, which allows for the targeted selection of protein-protein interactions of a desired affinity range. This thesis additionally describes the development and characterization of a synthetic protein that was designed to investigate chromophore reconstitution in photoactive yellow protein (PYP), a promising scaffold for engineering photo-controlled protein tools.
Earthquake swarms are characterized by large numbers of events occurring in a short period of time within a confined source volume and without significant mainshock aftershock pattern as opposed to tectonic sequences. Intraplate swarms in the absence of active volcanism usually occur in continental rifts as for example in the Eger Rift zone in North West Bohemia, Czech Republic. A common hypothesis links event triggering to pressurized fluids. However, the exact causal chain is often poorly understood since the underlying geotectonic processes are slow compared to tectonic sequences. The high event rate during active periods challenges standard seismological routines as these are often designed for single events and therefore costly in terms of human resources when working with phase picks or computationally costly when exploiting full waveforms.
This methodological thesis develops new approaches to analyze earthquake swarm seismicity as well as the underlying seismogenic volume. It focuses on the region of North West (NW) Bohemia, a well studied, well monitored earthquake swarm region.
In this work I develop and test an innovative approach to detect and locate earthquakes using deep convolutional neural networks. This technology offers great potential as it allows to efficiently process large amounts of data which becomes increasingly important given that seismological data storage grows at increasing pace. The proposed deep neural network trained on NW Bohemian earthquake swarm records is able to locate 1000 events in less than 1 second using full waveforms while approaching precision of double difference relocated catalogs. A further technological novelty is that the trained filters of the deep neural network’s first layer can be repurposed to function as a pattern matching event detector without additional training on noise datasets. For further methodological development and benchmarking, I present a new toolbox to generate realistic earthquake cluster catalogs as well as synthetic full waveforms of those clusters in an automated fashion. The input is parameterized using constraints on source volume geometry, nucleation and frequency-magnitude relations. It harnesses recorded noise to produce highly realistic synthetic data for benchmarking and development. This tool is used to study and assess detection performance in terms of magnitude of completeness Mc of a full waveform detector applied to synthetic data of a hydrofracturing experiment at the Wysin site, Poland.
Finally, I present and demonstrate a novel approach to overcome the masking effects of wave propagation between earthquake and stations and to determine source volume attenuation directly in the source volume where clustered earthquakes occur. The new event couple spectral ratio approach exploits high frequency spectral slopes of two events sharing the greater part of their rays. Synthetic tests based on the toolbox mentioned before show that this method is able to infer seismic wave attenuation within the source volume at high spatial resolution. Furthermore, it is independent from the distance towards a station as well as the complexity of the attenuation and velocity structure outside of the source volume of swarms. The application to recordings of the NW Bohemian earthquake swarm shows increased P phase attenuation within the source volume (Qp < 100) based on results at a station located close to the village Luby (LBC). The recordings of a station located in epicentral proximity, close to Nový Kostel (NKC), show a relatively high complexity indicating that waves arriving at that station experience more scattering than signals recorded at other stations. The high level of complexity destabilizes the inversion. Therefore, the Q estimate at NKC is not reliable and an independent proof of the high attenuation finding given the geometrical and frequency constraints is still to be done. However, a high attenuation in the source volume of NW Bohemian swarms has been postulated before in relation to an expected, highly damaged zone bearing CO 2 at high pressure.
The methods developed in the course of this thesis yield the potential to improve our understanding regarding the role of fluids and gases in intraplate event clustering.
Die Anfechtbarkeit und die Feststellbarkeit der Mutterschaft de lege lata und de lege ferenda
(2019)
Der althergebrachte Grundsatz, wonach das Kind von der Frau abstammt, welche es geboren hat, ist durch die moderne Fortpflanzungsmedizin ins Wanken geraten. Dennoch ordnet § 1591 BGB das Kind unanfechtbar der Geburtsmutter zu. Rechtliche und genetische Mutterschaft fallen deshalb dauerhaft auseinander, wenn das Kind im Wege der Leihmutterschaft oder nach einer Eizell- bzw. Embryospende zur Welt kommt. Die auf diese Methoden der artifiziellen Reproduktion bezogenen, im Inland bestehenden Verbote halten Paare mit Kinderwunsch nicht davon ab, auf entsprechende Angebote im Ausland zurückzugreifen. Daraus resultierende kollisions- und verfassungsrechtliche Probleme sind Gegenstand der vorliegenden Arbeit.
Für den Bereich der Leihmutterschaft wird der Frage nachgegangen, ob die mit dem Anfechtungsausschluss verfolgten Ziele des Gesetzgebers die damit einhergehenden Beeinträchtigungen grundrechtlich geschützter Rechtspositionen von genetischer Mutter und Kind rechtfertigen können. Besonderes Augenmerk liegt auf dem von Art. 6 Abs. 2 S. 1 GG geschützten Interesse von leiblichen Eltern und Kindern, die verfahrensrechtliche Möglichkeit zu erhalten, rechtlich einander zugeordnet zu werden. Dieses Interesse wird den Zielen des Gesetzgebers, der mit dem Anfechtungsausschluss die Rechte von Leihmüttern und Kindern zu schützen beabsichtigt, im Rahmen einer umfassenden Verhältnismäßigkeitsprüfung gegenübergestellt.
In den Konstellationen der Eizell- und Embryospende tritt schwerpunktmäßig das Recht des Kindes auf Kenntnis der eigenen Abstammung in den Vordergrund und mit ihm die Frage, ob sich daraus eine Verpflichtung des Gesetzgebers ableiten lässt, den Tatbestand von § 1598a BGB so zu erweitern, dass die vermuteten genetischen Eltern für den Bereich der artifiziellen Reproduktion in den Kreis der Klärungsverpflichteten aufgenommen werden.
Neben diesen Schwerpunkten werden viele weitere Probleme angesprochen. Im Ergebnis mündet die Arbeit in einen Vorschlag für die Legislative.
In this thesis we introduce the concept of the degree of formality. It is directed against a dualistic point of view, which only distinguishes between formal and informal proofs. This dualistic attitude does not respect the differences between the argumentations classified as informal and it is unproductive because the individual potential of the respective argumentation styles cannot be appreciated and remains untapped.
This thesis has two parts. In the first of them we analyse the concept of the degree of formality (including a discussion about the respective benefits for each degree) while in the second we demonstrate its usefulness in three case studies. In the first case study we will repair Haskell B. Curry's view of mathematics, which incidentally is of great importance in the first part of this thesis, in light of the different degrees of formality. In the second case study we delineate how awareness of the different degrees of formality can be used to help students to learn how to prove. Third, we will show how the advantages of proofs of different degrees of formality can be combined by the development of so called tactics having a medium degree of formality. Together the three case studies show that the degrees of formality provide a convincing solution to the problem of untapped potential.
With the growth of information technology, patient attitudes are shifting – away from passively receiving care towards actively taking responsibility for their well- being. Handling doctor-patient relationships collaboratively and providing patients access to their health information are crucial steps in empowering patients. In mental healthcare, the implicit consensus amongst practitioners has been that sharing medical records with patients may have an unpredictable, harmful impact on clinical practice. In order to involve patients more actively in mental healthcare processes, Tele-Board MED (TBM) allows for digital collaborative documentation in therapist-patient sessions. The TBM software system offers a whiteboard-inspired graphical user interface that allows therapist and patient to jointly take notes during the treatment session. Furthermore, it provides features to automatically reuse the digital treatment session notes for the creation of treatment session summaries and clinical case reports. This thesis presents the development of the TBM system and evaluates its effects on 1) the fulfillment of the therapist’s duties of clinical case documentation, 2) patient engagement in care processes, and 3) the therapist-patient relationship. Following the design research methodology, TBM was developed and tested in multiple evaluation studies in the domains of cognitive behavioral psychotherapy and addiction care. The results show that therapists are likely to use TBM with patients if they have a technology-friendly attitude and when its use suits the treatment context. Support in carrying out documentation duties as well as fulfilling legal requirements contributes to therapist acceptance. Furthermore, therapists value TBM as a tool to provide a discussion framework and quick access to worksheets during treatment sessions. Therapists express skepticism, however, regarding technology use in patient sessions and towards complete record transparency in general. Patients expect TBM to improve the communication with their therapist and to offer a better recall of discussed topics when taking a copy of their notes home after the session. Patients are doubtful regarding a possible distraction of the therapist and usage in situations when relationship-building is crucial. When applied in a clinical environment, collaborative note-taking with TBM encourages patient engagement and a team feeling between therapist and patient. Furthermore, it increases the patient’s acceptance of their diagnosis, which in turn is an important predictor for therapy success. In summary, TBM has a high potential to deliver more than documentation support and record transparency for patients, but also to contribute to a collaborative doctor-patient relationship. This thesis provides design implications for the development of digital collaborative documentation systems in (mental) healthcare as well as recommendations for a successful implementation in clinical practice.
One method of embedding groups into skew fields was introduced by A. I. Mal'tsev and B. H. Neumann (cf. [18, 19]). If G is an ordered group and F is a skew field, the set F((G)) of formal power series over F in G with well-ordered support forms a skew field into which the group ring F[G] can be embedded. Unfortunately it is not suficient that G is left-ordered since F((G)) is only an F-vector space in this case as there is no natural way to define a multiplication on F((G)). One way to extend the original idea onto left-ordered groups is to examine the endomorphism ring of F((G)) as explored by N. I. Dubrovin (cf. [5, 6]). It is possible to embed any crossed product ring F[G; η, σ] into the endomorphism ring of F((G)) such that each non-zero element of F[G; η, σ] defines an automorphism of F((G)) (cf. [5, 10]). Thus, the rational closure of F[G; η, σ] in the endomorphism ring of F((G)), which we will call the Dubrovin-ring of F[G; η, σ], is a potential candidate for a skew field of fractions of F[G; η, σ]. The methods of N. I. Dubrovin allowed to show that specific classes of groups can be embedded into a skew field. For example, N. I. Dubrovin contrived some special criteria, which are applicable on the universal covering group of SL(2, R). These methods have also been explored by J. Gräter and R. P. Sperner (cf. [10]) as well as N.H. Halimi and T. Ito (cf. [11]). Furthermore, it is of interest to know if skew fields of fractions are unique. For example, left and right Ore domains have unique skew fields of fractions (cf. [2]). This is not the general case as for example the free group with 2 generators can be embedded into non-isomorphic skew fields of fractions (cf. [12]). It seems likely that Ore domains are the most general case for which unique skew fields of fractions exist. One approach to gain uniqueness is to restrict the search to skew fields of fractions with additional properties. I. Hughes has defined skew fields of fractions of crossed product rings F[G; η, σ] with locally indicable G which fulfill a special condition. These are called Hughes-free skew fields of fractions and I. Hughes has proven that they are unique if they exist [13, 14]. This thesis will connect the ideas of N. I. Dubrovin and I. Hughes. The first chapter contains the basic terminology and concepts used in this thesis. We present methods provided by N. I. Dubrovin such as the complexity of elements in rational closures and special properties of endomorphisms of the vector space of formal power series F((G)). To combine the ideas of N.I. Dubrovin and I. Hughes we introduce Conradian left-ordered groups of maximal rank and examine their connection to locally indicable groups. Furthermore we provide notations for crossed product rings, skew fields of fractions as well as Dubrovin-rings and prove some technical statements which are used in later parts. The second chapter focuses on Hughes-free skew fields of fractions and their connection to Dubrovin-rings. For that purpose we introduce series representations to interpret elements of Hughes-free skew fields of fractions as skew formal Laurent series. This 1 Introduction allows us to prove that for Conradian left-ordered groups G of maximal rank the statement "F[G; η, σ] has a Hughes-free skew field of fractions" implies "The Dubrovin ring of F [G; η, σ] is a skew field". We will also prove the reverse and apply the results to give a new prove of Theorem 1 in [13]. Furthermore we will show how to extend injective ring homomorphisms of some crossed product rings onto their Hughes-free skew fields of fractions. At last we will be able to answer the open question whether Hughes--free skew fields are strongly Hughes-free (cf. [17, page 53]).