Magnetische Mikrokalorimeter : Hochauflösende Röntgenspektroskopie mit energiedispersiven Detektoren

In der vorliegenden Arbeit wird die Entwicklung eines metallischen magnetischen Mikrokalorimeters zum hochauflösenden Nachweis von einzelnen Röntgenquanten diskutiert. Der Detektor besteht aus einem Röntgenabsorber und einem paramagnetischen Temperatursensor, über dessen Magnetisierung der Energieinhalt des kalorimetrischen Detektors bestimmt werden kann. Misst man die kleine Magnetisierungsänderung, die der Absorption eines Röntgenquantes folgt mit einem rauscharmen SQUID-Magnetometer, so erhält man durch diese ein Maß für die in den Detektor eingetragene Energie. Es wird ein theoretisches Modell vorgestellt, das die thermodynamischen Eigenschaften der Detektoren gut beschreibt, und dadurch die Optimierung des Detektoraufbaus hinsichtlich der Signalgröße ermöglicht. Die Diskussion der maximal erreichbaren Energieauflösung ergibt, dass diese durch die thermodynamischen Energiefluktuationen zwischen den Subsystemen des Detektors fundamental limitiert ist. Die Realisierung eines digitalen optimalen Filters zur Datenanalyse wird vorgestellt und seine Eigenschaften diskutiert. Mit einem Prototypdetektor, dessen zwei Röntgensensoren von einem SQUID-Gradiometer ausgelesen werden, und der eine Quanteneffizienz von über 98% für Röntgenquanten von 6 keV besitzt, wurde eine Energieauflösung von dE_FWHM = 3,4 eV erreicht

Management of Acute Myeloid Leukemia: Current Treatment Options and Future Perspectives

Simple Summary AML is a genetically heterogeneous disease with a median age of diagnosis between 60 and 70 years. Thus, many AML patients are not eligible for intensive chemotherapy. Often, the disease is accompanied by a poor prognosis due to high-risk genetic features or due to antecedent hematologic disorders (e.g., myelodysplastic syndrome). Therefore, AML treatment remains a challenge; even after intensive chemotherapy and allogeneic stem cell transplantation (alloHSCT), AML relapses are regularly observed. Thus, new concepts of AML therapy, considering tailored treatment approaches after comprehensive molecular diagnostic or implementing new immunotherapeutic strategies, are urgently needed. This review provides a detailed overview of recent developments and current promising concepts to improve the treatment and the outcome of AML patients. Abstract Treatment of acute myeloid leukemia (AML) has improved in recent years and several new therapeutic options have been approved. Most of them include mutation-specific approaches (e.g., gilteritinib for AML patients with activating FLT3 mutations), or are restricted to such defined AML subgroups, such as AML-MRC (AML with myeloid-related changes) or therapy-related AML (CPX-351). With this review, we aim to present a comprehensive overview of current AML therapy according to the evolved spectrum of recently approved treatment strategies. We address several aspects of combined epigenetic therapy with the BCL-2 inhibitor venetoclax and provide insight into mechanisms of resistance towards venetoclax-based regimens, and how primary or secondary resistance might be circumvented. Furthermore, a detailed overview on the current status of AML immunotherapy, describing promising concepts, is provided. This review focuses on clinically important aspects of current and future concepts of AML treatment, but will also present the molecular background of distinct targeted therapies, to understand the development and challenges of clinical trials ongoing in AML patients

Attracted to feed, not to be fed upon – on the biology of Toxomerus basalis (Walker, 1836), the kleptoparasitic ‘sundew flower fly’ (Diptera: Syrphidae)

The complete life history of the kleptoparasitic ‘sundew flower fly’, Toxomerus basalis, is presented and illustrated. Adults of this species are photographed alive for the first time, including video recordings of larval and adult behaviour. Adult flies of both sexes visit Drosera (sundews) and show territorial behaviour around the plants, avoiding the dangerous sticky traps and demonstrating recognition of their larval host plant. Females lay eggs directly on non-sticky parts of the Drosera host plants, such as on the lower surface of the leaves and flower stalks, but apparently also on other plants growing in close proximity with the sundews.2018 fieldwork in Minas Gerais by AF and PMG was supported by travel funding from the project ‘SNSB-Innovativ 2018’ by the SNSB – Staatliche Naturwissenschaftliche Sammlungen Bayerns (Bavarian Natural History Collections, Germany) to AF. PMG thanks The Mohamed bin Zayed Species Conservation Fund for financial support for field work at Serra do Padre Ângelo (grant 192522325). Fieldwork was conducted under research permit granted by the Authorization and Information System in Biodiversity (SisBio), from the Chico Mendes Institute for Biodiversity Conservation (ICMBio) (#67026-1) to PMG

Elucidating the controversial Drosera montana complex (Droseraceae): a taxonomic revision

author for correspondence The species of the affinity of Drosera montana (Droseraceae) are reviewed taxonomically and the complex is redefined t

Diffusive clustering in an infinite system of hierarchically interacting diffusions.

We study a countable system of interacting diffusions on the interval [0,1], indexed by a hierarchical group. A particular choice of the interaction guarantees, we are in the diffusive clustering regime. This means clusters of components with values either close to 0 or close to 1 grow on various different scales. However, single components oscillate infinitely often between values close to 0 and close to 1 in such a way that they spend fraction one of their time together and close to the boundary. The processes in the whole class considered and starting with a shift-ergodic initial law have the same qualitative properties (universality)

Measuring Magnetic 1/f Noise in Superconducting Microstructures and the Fluctuation-Dissipation Theorem

The performance of superconducting devices like qubits, SQUIDs, and particle detectors is often limited by finite coherence times and 1/f noise. Various types of slow fluctuators in the Josephson junctions and the passive parts of these superconducting circuits can be the cause, and devices usually suffer from a combination of different noise sources, which are hard to disentangle and therefore hard to eliminate. One contribution is magnetic 1/f noise caused by fluctuating magnetic moments of magnetic impurities or dangling bonds in superconducting inductances, surface oxides, insulating oxide layers, and adsorbates. In an effort to further analyze such sources of noise, we have developed an experimental set-up to measure both the complex impedance of superconducting microstructures, and the overall noise picked up by these structures. This allows for important sanity checks by connecting both quantities via the fluctuation-dissipation theorem. Since these two measurements are sensitive to different types of noise, we are able to identify and quantify individual noise sources. The superconducting inductances under investigation form a Wheatstone-like bridge, read out by two independent cross-correlated dc-SQUID read-out chains. The resulting noise resolution lies beneath the quantum limit of the front-end SQUIDs and lets us measure noise caused by just a few ppm of impurities in close-by materials. We present measurements of the insulating SiO2 layers of our devices, and magnetically doped noble metal layers in the vicinity of the pickup coils at T = 30 mK - 800 mK and f = 1 Hz - 100 kHz.Comment: 13 pages, 5 figure

Development and characterisation of high-resolution microcalorimeter detectors for the ECHo-100k experiment

The goal of the ECHo experiment is a direct determination of the absolute scale of the neutrino mass by the analysis of the end-point region of the Ho-163 electron capture (EC) spectrum. The results of the first phase of the experiment, ECHo-1k, have paved the way for the current phase, ECHo-100k, which aims at a sensitivity below 2 eV on the effective electron neutrino mass. In order to reach this goal, a new generation of high-resolution magnetic microcalorimeters with embedded Ho-163 have been developed and characterised. The design has been optimised to meet all the challenging requirements of the ECHo-100k experimental phase, such as excellent energy resolution, wafer scale implantation and multi-chip operation with multiplexing read-out. We present the optimisation studies, the final design of the detector array and the first characterisation studies. The results demonstrate that the detectors fully match and even surpass the requirements for the current experimental phase, ECHo-100k