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Radioactive ion beams (RIB) are a key focus of current research in nuclear physics. Already long ago it was proposed that they could have applications in cancer therapy. In fact, while charged particle therapy is potentially the most effective radiotherapy technique available, it is highly susceptible to uncertainties in the beam range. RIB are well-suited for image-guided particle therapy, as isotopes that undergo \b{eta}+-decay can be precisely visualized using positron emission tomography (PET), enabling accurate real-time monitoring of the beam range. We successfully treated a mouse osteosarcoma using a radioactive 11C-ion beam. The tumor was located in the neck, in close proximity to the spinal cord, increasing the risk of radiation-induced myelopathy from even slight variations in the beam range caused by anatomical changes or incorrect calibration of the planning CT. We managed to completely control the tumor with the highest dose while minimizing toxicity. Low-grade neurological side effects were correlated to the positron activity measured in the spine. The biological washout of the activity from the tumor volume was dependent on the dose, indicating a potential component of vascular damage at high doses. This experiment marks the first instance of tumor treatment using RIB and paves the way for future clinical applications., Comment: 56 pages, 13 figures, supplements. Video supplements available on request

Thin films made of deformable micro- and nano-units, such as biological membranes, polymer interfaces, and particle-laden liquid surfaces, exhibit a complex behavior during drying, with consequences for various applications like wound healing, coating technologies, and additive manufacturing. Studying the drying dynamics and structural changes of soft colloidal films thus holds the potential to yield valuable insights to achieve improvements for applications. In this study, we employ interfacial monolayers of core-shell microgels with varying degrees of softness as model systems and investigate their drying behavior on differently modified solid substrates (hydrophobic vs. hydrophilic). By leveraging on video microscopy, particle tracking, and thin film interference, we shed light on the interplay between microgel adhesion to solid surfaces and the immersion capillary forces that arise in the thin liquid film. We discovered that a dried replica of the interfacial microstructure can be more accurately achieved on a hydrophobic substrate relative to a hydrophilic one, particularly when employing softer colloids as opposed to harder counterparts. These observations are qualitatively supported by experiments with a thin film pressure balance which allows mimicking and controlling the drying process and by computer simulations with coarse-grained models., Comment: 36 pages of main manuscript with 9 figures and 1 table, 22 pages of Supporting Information with 21 figures and 4 tables

Despite the remarkable progress in emerging solar cell technologies such as hybrid organic-inorganic perovskites, there are still significant limitations related to the stability of the devices and their non-ideal electrical behavior under certain external stimuli. We present a conceptual framework for characterizing photovoltaic devices by integrating cyclic voltammetry (CV) and impedance spectroscopy (IS). This framework is constructed from a microscopic, multi-mode perspective that explicitly accounts for drift, diffusion, displacement, and memory contributions. We derive comprehensive analytical expressions for current-voltage relationships and complex admittance. Our model reveals the inseparable connection between hysteresis behaviors in current-voltage characteristics observed in CV and the apparent capacitive and inductive behaviors seen in IS spectral analysis. We demonstrate how CV and IS naturally complement each other, providing a deeper microscopic understanding of device performance and limitations. Additionally, we establish the relationship between intrinsic material parameters and experimentally accessible extrinsic parameters such as light intensity, temperature, DC bias, voltage amplitude, and frequency. This framework enables unprecedented optimization of solar cell performance, marking a significant advancement towards sustainability., Comment: 6 figures

A renewed interest in upright therapy is currently driven by the availability of upright positioning and imaging systems. Aside from reduced cost, upright positioning possibly provides clinical advantages. The comparison between upright and supine particle therapy treatments can be biased through multiple variables, such as differences in the target contouring on the two CTs. We present a method for upright and supine CT registration and structures propagation, and the investigation of an AI-based contouring tool for upright images. Six paired 4DCTs from Proton Therapy Collaboration Group registry were available from the Northwestern Medicine Proton Centre. Deformable image registration (DIR) is challenged by the different patient anatomy between postures, causing artefacts in the warped images. To achieve high quality contour propagation, we propose the construction of a region of interest covering the ribcage volume to overcome this problem. As no target contour ground truth was available, the registration quality analysis (QA) was performed on lung structures, for which dice score coefficient (DSC) and average Hausdorff distance (AHD) is reported. The TotalSegmentator tool, trained on supine dataset, was applied on upright images, verified against lung structures and used as additional comparison for contour propagation. The TotalSegmentator QA results in a maximum AHD of 2mm and a minimum DSC of 0.94. An average AHD of 1.5mm and 1.6mm, and an average DSC of 0.95 and 0.94 were obtained comparing the propagated volumes to manually contoured and AI structures, respectively. All AHD values are smaller than the CT slice distances. The developed framework allows for target propagation between upright and supine images, defining the first step to compare upright and supine therapy of thoracic patients and enabling the application of image fusion techniques in the upright therapy field.

Radiotherapy with heavy ions, in particular, 12C beams, is one of the most advanced forms of cancer treatment. Sharp dose gradients and high biological effectiveness in the target region make them an ideal tool to treat deep-seated and radioresistant tumors, however, at the same time, sensitive to small errors in the range prediction. Safety margins are added to the tumor volume to mitigate these uncertainties and ensure its uniform coverage, but during the irradiation they lead to unavoidable damage to the surrounding healthy tissue. To fully exploit the benefits of a sharp Bragg peak, a large effort is put into establishing precise range verification methods for the so-called image-guided radiotherapy. Despite positron emission tomography being widely in use for this purpose in 12C ion therapy, the low count rates, biological washout, and broad shape of the activity distribution still limit its precision to a few millimeters. Instead, radioactive beams used directly for treatment would yield an improved signal and a closer match with the dose fall-off, potentially enabling precise in vivo beam range monitoring. We have performed a treatment planning study to estimate the possible impact of the reduced range uncertainties, enabled by radioactive 11C beams treatments, on sparing critical organs in the tumor proximity. We demonstrate that (i) annihilation maps for 11C ions can in principle reflect even millimeter shifts in dose distributions in the patient, (ii) outcomes of treatment planning with 11C beams are significantly improved in terms of meeting the constraints for the organs at risk compared to 12C plans, and (iii) less severe toxicities for serial and parallel critical organs can be expected following 11C treatment with reduced range uncertainties, compared to 12C treatments.

The melanins are a ubiquitous class of pigments found throughout nature from lower organisms to humans. It is one of the few biopolymers with fascinating functions in biology, medicine, chemistry, physics and engineering due to its relation to neurological diseases, skin disorders and melanoma, and, in the last couple of decades, its applications in biocompatible and biodegradable devices for organic electronic and bioelectronics. In this review, we present the major advances in physicochemical, biochemical and photochemical properties as well as some melanin-based technological application. Keywords: Melanin; physical-chemical properties; biochemistry; photochemistry technological applications., Comment: 32 pages, in Portuguese, 1 figure, 3 schemes

Because of its high mass, the X-ray binary system LMC X-3 is a candidate for a binary system hosting a black hole. The goal of this work is to determine the mass of this black hole and the orbital inclination of the system. Therefore, data from the GROND instrument at the MPI/ESO 2.2m telescope at La Silla, Chile that was recorded between Oktober 20, 2007 and December 13, 2013 was analyzed. The program 'XRbinary' from Edward L. Robinson was used to describe the data and invert for the black hole mass and the orbital inclination of the binary system. The mass of the black hole was determined to ($7.15\pm0.65$) solar masses and the inclination to ($68^{+2}_{-3}$) degrees. From these two quantities, estimations about the rotation of the black hole in LMC X-3 can be derived and the mass distribution of black holes in X-ray binaries can be expanded., Comment: Bachelor Thesis at the Technical University of Munich (TUM), in German

Different extensions of the Nambu-Jona-Lasinio model, known to satisfy expected QCD chiral symmetry aspects, are used to investigate a possible hadron-quark phase transition at zero temperature and to build the corresponding binodal sections. We have shown that the transition point is very sensitive to the model parameters and that both pressure and chemical potential increase drastically with the increase of the vector interaction strength in the quark sector. Within the same framework, the possibility of quark and hybrid star formation is analyzed. The same conclusions drawn before with respect to the coexistence pressure and chemical potentials are reinforced. We conclude that even if a transition from a metastable hadronic star to a quark star is thermodinamically possible, it is either energetically forbidden or gives rise to a blackhole. Nevertheless, conversions from metastable to hybrid stars are possible, but the mass difference between both compact objects is very small, never larger than 0.2 M$_\odot$., Comment: 21 pages, 7 figures

The integral field spectrograph, SPIFFI, has complex line profile shapes that vary with wavelength and pixel scale, the origins of which have been sought since the instrument construction. SPIFFI is currently operational as part of SINFONI at the VLT, and will be upgraded and incorporated into the new VLT instrument ERIS. We conducted an investigation of the line profiles based on measurements we could take with the instrument calibration unit, as well as laboratory measurements of spare SPIFFI optical components. Cryogenic measurements of a spare SPIFFI diffraction grating showed significant periodic deformation. These measurements match the cryogenic deformation expected from bimetallic bending stress based on a finite element analysis of the lightweighted grating blank. The periodic deformation of the grating surface gives rise to satellite peaks in the diffraction pattern of the grating. An optical simulation including the cryogenic grating deformation reproduces the behavior of the SPIFFI line profiles with both wavelength and pixel scale as measured with the instrument calibration unit. The conclusion is that cryogenic deformation of the diffraction gratings is responsible for the non-ideal line profiles, and that the diffraction gratings should be replaced during the upgrade for optimal instrument performance., Comment: 26 page, 18 figures

The SPIFFI integral field spectrometer is operated as a subunit of the AO instrument SINFONI on the VLT. It will be upgraded and reused as SPIFFIER in the new VLT instrument ERIS. In January 2016 an early upgrade of several optical components was carried out to make use of new technological developments before ERIS will be commissioned in 2020. This Master's thesis focuses on the determination and detailed description of the gain in performance due to the upgrade, with a particular focus on measurements of the exchanged diamond turned mirrors of SPIFFI. An analysis of the surface deformation of these mirrors is done, followed by a determination of the resulting collimator wavefront and its influence on the line spread function of the spectrometer. A careful analysis on the shapes, the variations and the changes of the spectral line profiles due to the upgrade is done. Furthermore, the spectral resolution, the image quality an the relative pre- and post- upgrade throughput ratio are evaluated. Finally these observed quantities are linked to critical optical components that limit the performance of the instrument., Comment: This is a Master's Thesis written at the Max Planck Institute For Extraterrestrial Physics and the Technical University of Munich. The working title of the thesis was: "Upgrade of the SPIFFI instrument with new optics, and characterization of the upgraded instrument"

SPIFFI is an AO-fed integral field spectrograph operating as part of SINFONI on the VLT, which will be upgraded and reused as SPIFFIER in the new VLT instrument ERIS. In January 2016, we used new technology developments to perform an early upgrade to optical subsystems in the SPIFFI instrument so ongoing scientific programs can make use of enhanced performance before ERIS arrives in 2020. We report on the upgraded components and the performance of SPIFFI after the upgrade, including gains in throughput and spatial and spectral resolution. We show results from re-commissioning, highlighting the potential for scientific programs to use the capabilities of the upgraded SPIFFI. Finally, we discuss the additional upgrades for SPIFFIER which will be implemented before it is integrated into ERIS., Comment: 20 pages, 12 figures. Proceedings from SPIE Astronomical Telescopes and Instrumentation 2016

Melanins are promising materials for organic bioelectronics devices like transistors, sensors and batteries. However, in general, melanin either natural or synthetic has low solubility in most solvents. In this study, the chemical structural changes of melanin synthesized, by the auto oxidation of L-DOPA, are analyzed for a new synthetic procedure using a reactor with oxygen pressure of 4 atm. UV-Vis spectroscopy, FTIR, C-NMR, XPS and TEM are use to characterize the material. Under oxygen pressure, the synthesis of melanin is accelerated and the polymer obtained is found to have higher carbonyl groups compared to conventional synthetic melanin. As a consequence it has higher homogeneity and is soluble in water. To explain these findings a reaction mechanism is proposed based on current melanogenesis models., Comment: 23 pages, 8 figures and 1 table

Designing 3D User Interfaces (UI) requires adequate evaluation tools to ensure good usability and user experience. While many evaluation tools are already available and widely used, existing approaches generally cannot provide continuous and objective measures of usa-bility qualities during interaction without interrupting the user. In this paper, we propose to use brain (with ElectroEncephaloGraphy) and physiological (ElectroCardioGraphy, Galvanic Skin Response) signals to continuously assess the mental effort made by the user to perform 3D object manipulation tasks. We first show how this mental effort (a.k.a., mental workload) can be estimated from such signals, and then measure it on 8 participants during an actual 3D object manipulation task with an input device known as the CubTile. Our results suggest that monitoring workload enables us to continuously assess the 3DUI and/or interaction technique ease-of-use. Overall, this suggests that this new measure could become a useful addition to the repertoire of available evaluation tools, enabling a finer grain assessment of the ergonomic qualities of a given 3D user interface., Comment: Published in INTERACT, Sep 2015, Bamberg, Germany

Continuous-wave electrically detected magnetic resonance (cw-EDMR or just EDMR) and its variants are powerful tools to investigate spin-dependent processes in materials and devices. The use of quadrature detection improves the quality and selectivity of EDMR analysis by allowing, for example, the separation of individual resonant spin lines. Here we propose an equivalent circuit model in order to better understand the EDMR quadrature signal in a variety of different situations. The model considers not just the electrical response of the sample but of cables and measuring circuit and its influence on the resulting spectral lines. Recent EDMR spectra from Alq3 based OLEDs, as well as from a-Si:H reported in the literature, were successfully described by the model. Moreover, the model allows the implementation of a fitting routine that can be easily used to determine accurate values of crucial parameters such as g-factor and linewidth of the resonant lines., Comment: 10 pages, 8 figures, original research article, being submitted to Journal of Applied Physics

Electrically Detected Magnetic Resonance (EDMR) was used to study a series of multilayer organic devices based on aluminum (III) 8-hydroxyquinoline. These devices were designed to identify the micoscopic origin of different spin dependent process, i.e. hopping and exciton formation. EDMR is demonstrated to probe molecular orbitals of charge, and thus indirectly explore interfaces, exciton formation, charge accumalation and electric fields in operating organic based devices.