Many-body localization of spinless fermions with attractive interactions in one dimension

We study the finite-energy density phase diagram of spinless fermions with attractive interactions in one dimension in the presence of uncorrelated diagonal disorder. Unlike the case of repulsive interactions, a delocalized Luttinger-liquid phase persists at weak disorder in the ground state, which is a well-known result. We revisit the ground-state phase diagram and show that the recently introduced occupation-spectrum discontinuity computed from the eigenspectrum of one-particle density matrices is noticeably smaller in the Luttinger liquid compared to the localized regions. Moreover, we use the functional renormalization scheme to study the finite-size dependence of the conductance, which resolves the existence of the Luttinger liquid as well and is computationally cheap. Our main results concern the finite-energy density case. Using exact diagonalization and by computing various established measures of the many-body localization-delocalization transition, we argue that the zero-temperature Luttinger liquid smoothly evolves into a finite-energy density ergodic phase without any intermediate phase transition

Neural \'{E}tendue Expander for Ultra-Wide-Angle High-Fidelity Holographic Display

Holographic displays can generate light fields by dynamically modulating the wavefront of a coherent beam of light using a spatial light modulator, promising rich virtual and augmented reality applications. However, the limited spatial resolution of existing dynamic spatial light modulators imposes a tight bound on the diffraction angle. As a result, modern holographic displays possess low \'{e}tendue, which is the product of the display area and the maximum solid angle of diffracted light. The low \'{e}tendue forces a sacrifice of either the field-of-view (FOV) or the display size. In this work, we lift this limitation by presenting neural \'{e}tendue expanders. This new breed of optical elements, which is learned from a natural image dataset, enables higher diffraction angles for ultra-wide FOV while maintaining both a compact form factor and the fidelity of displayed contents to human viewers. With neural \'{e}tendue expanders, we experimentally achieve 64$\times$ \'{e}tendue expansion of natural images in full color, expanding the FOV by an order of magnitude horizontally and vertically, with high-fidelity reconstruction quality (measured in PSNR) over 29 dB on retinal-resolution images

AMPK - Activated Protein Kinase and its Role in Energy Metabolism of the Heart

Adenosine monophosphate – activated kinase (AMPK) plays a key role in the coordination of the heart’s anabolic and catabolic pathways. It induces a cellular cascade at the center of maintaining energy homeostasis in the cardiomyocytes.. The activated AMPK is a heterotrimeric protein, separated into a catalytic α - subunit (63kDa), a regulating β - subunit (38kDa) and a γ - subunit (38kDa), which is allosterically adjusted by adenosine triphosphate (ATP) and adenosine monophosphate (AMP). The actual binding of AMP to the γ – subunit is the step which activates AMPK

Analyses of Phospho-AMPK α, VEGF-A , VEGF-R2 in myocardium and investigations in morphological changes in a model of chronic heart failure induced by multiple sequential coronary microembolization in sheep

Die Basis und zugleich Mittelpunkt dieser Dissertation bildete das Modell der chronischen Herzinsuffizienz (vergleichbar NYHA III), induziert durch sequentielle, repetitive koronare Mikroembolisation an der Spezies Schaf. Im Rahmen dieser Dissertation gelang erstmalig eine morphologische Systemvalidierung (HE- und PSR-Färbungen von Myokard-, Leber- und Nierengewebe) zur Prüfung eines Vorwärts- sowie Rückwärtsversagens, welches bereits durch hämodynamische Analysen verifiziert wurde. Des Weiteren wurde mit Hilfe der RT-PCR und des Western Blotting Phospho-AMPK α, VEGF-A und VEGF-R2 analysiert. Ziel war die Definition von Kompensationsmechanismen, die für eine Adaptation an die induzierte Druck- und Volumenbelastung verantwortlich sein könnten. AMPK agiert als zentrales Schlüsselenzym im kardialen Energiestoffwechsel und besitzt verschiedene kardioprotektive Eigenschaften. Mit VEGF-A und VEGF-R2 wurden obligate Parameter der Neoangiogenese (suffiziente Kollateralisierung) untersucht. Repetitive, sequentielle Mikroembolisation induziert eine ischämische Kardiomyopathie und führen konsekutiv zu pathologischen Veränderungen der Leber und Niere. Quantitative sowie qualitative Analysen zeigten einen signifikanten Anstieg der Phosphorylierung von AMPK. Die ermittelten Werte von VEGF-A und VEGF-R2 lagen stets im Bereich der Kontrollgruppe. Somit könnte lediglich Phospho-AMPK α als möglicher Kompensationsmechanismus postuliert werden. Die retrospektive Betrachtung aller Ergebnisse ergab eine führende rechtsventrikuläre Schädigung. Infolgedessen konnte eindrucksvoll herausgearbeitet werden, dass sich das etablierte Versuchstiermodell primär für Studien einer Globalinsuffizienz und nicht hingegen, wie angenommen, für Studien einer isolierten Linksherzinsuffizienz eignet

Optimization, Design, and Manufacturing of New Steel-FRP Automotive Fuel Cell Medium Pressure Plate Using Compression Molding

In this work, a new plastic-intensive medium-pressure plate (MPP), which is part of a fuel-cell system, has been developed together with a steel plate meeting all mechanical and chemical requirements. This newly developed MPP had to achieve the objective of saving weight and package space. The use of compression molding as a manufacturing technique facilitated the use of glass mat thermoplastics (GMT) which has higher E-modules and strength compared to most of the injection molded materials. A steel plate was placed as an insert to help achieve the stiffness requirements. For the development, the existing MPP was benchmarked for its structural capabilities and its underlying functional features. Four different FRP materials were investigated in terms of their chemical and mechanical properties. PP-GMT material, which has both high mechanical performance and resistance against chemicals in the fuel cell fluid, had been chosen. Using the properties of the chosen PP-GMT material, topology optimization was carried out based on the quasi-static load case and manufacturing constraints, which gave a load-conforming rib structure. The obtained rib structure was utilized to develop the final MPP with adherence to the functional requirements of MPP. The developed plastic-intensive MPP exhibits a 3-in-1 component feature with a 55% reduction in package space and an 8% weight reduction. The MPP was virtually analyzed for its mechanical strength and compared with the existing benchmark values. Finally, a press tool was conceptualized and manufactured to fabricate the new plastic-intensive MPP, which was tested in a rig and validated in the FE model