Melt-Extrusion-Based Additive Manufacturing of Transparent Fused Silica Glass

In recent years, additive manufacturing (AM) of glass has attracted great interest in academia and industry, yet it is still mostly limited to liquid nanocomposite-based approaches for stereolithography, two-photon polymerization, or direct ink writing. Melt-extrusion-based processes, such as fused deposition modeling (FDM), which will allow facile manufacturing of large thin-walled components or simple multimaterial printing processes, are so far inaccessible for AM of transparent fused silica glass. Here, melt-extrusion-based AM of transparent fused silica is introduced by FDM and fused feedstock deposition (FFD) using thermoplastic silica nanocomposites that are converted to transparent glass using debinding and sintering. This will enable printing of previously inaccessible glass structures like high-aspect-ratio (>480) vessels with wall thicknesses down to 250 µm, delicate parts including overhanging features using polymer support structures, as well as dual extrusion for multicolored glasses

Quantum nonlinear dynamics of continuously measured systems

Classical dynamics is formulated as a Hamiltonian flow on phase space, while quantum mechanics is formulated as a unitary dynamics in Hilbert space. These different formulations have made it difficult to directly compare quantum and classical nonlinear dynamics. Previous solutions have focussed on computing quantities associated with a statistical ensemble such as variance or entropy. However a more direct comparison would compare classical predictions to the quantum for continuous simultaneous measurement of position and momentum of a single system. In this paper we give a theory of such measurement and show that chaotic behaviour in classical systems can be reproduced by continuously measured quantum systems.Comment: 11 pages, REVTEX, 3 figure

Continuous Quantum Measurement and the Emergence of Classical Chaos

We formulate the conditions under which the dynamics of a continuously measured quantum system becomes indistinguishable from that of the corresponding classical system. In particular, we demonstrate that even in a classically chaotic system the quantum state vector conditioned by the measurement remains localized and, under these conditions, follows a trajectory characterized by the classical Lyapunov exponent.Comment: 5 pages, multicol revte

Continuous Quantum Measurement and the Quantum to Classical Transition

While ultimately they are described by quantum mechanics, macroscopic mechanical systems are nevertheless observed to follow the trajectories predicted by classical mechanics. Hence, in the regime defining macroscopic physics, the trajectories of the correct classical motion must emerge from quantum mechanics, a process referred to as the quantum to classical transition. Extending previous work [Bhattacharya, Habib, and Jacobs, Phys. Rev. Lett. {\bf 85}, 4852 (2000)], here we elucidate this transition in some detail, showing that once the measurement processes which affect all macroscopic systems are taken into account, quantum mechanics indeed predicts the emergence of classical motion. We derive inequalities that describe the parameter regime in which classical motion is obtained, and provide numerical examples. We also demonstrate two further important properties of the classical limit. First, that multiple observers all agree on the motion of an object, and second, that classical statistical inference may be used to correctly track the classical motion.Comment: 12 pages, 4 figures, Revtex

Soluble mannose receptor induces proinflammatory macrophage activation and metaflammation

Proinflammatory activation of macrophages in metabolic tissues is critically important in the induction of obesity-induced metaflammation. Here, we demonstrate that the soluble mannose receptor (sMR) plays a direct functional role in both macrophage activation and metaflammation. We show that sMR binds CD45 on macrophages and inhibits its phosphatase activity, leading to an Src/Akt/ NF-kappa B-mediated cellular reprogramming toward an inflammatory phenotype both in vitro and in vivo. Remarkably, increased serum sMR levels were observed in obese mice and humans and directly correlated with body weight. Importantly, enhanced sMR levels increase serum proinflammatory cytokines, activate tissue macrophages, and promote insulin resistance. Altogether, our results reveal sMR as regulator of proinflammatory macrophage activation, which could constitute a therapeutic target for metaflammation and other hyperinflammatory diseases.Diabetes mellitus: pathophysiological changes and therap

The delta-function-kicked rotor: Momentum diffusion and the quantum-classical boundary

We investigate the quantum-classical transition in the delta-kicked rotor and the attainment of the classical limit in terms of measurement-induced state-localization. It is possible to study the transition by fixing the environmentally induced disturbance at a sufficiently small value, and examining the dynamics as the system is made more macroscopic. When the system action is relatively small, the dynamics is quantum mechanical and when the system action is sufficiently large there is a transition to classical behavior. The dynamics of the rotor in the region of transition, characterized by the late-time momentum diffusion coefficient, can be strikingly different from both the purely quantum and classical results. Remarkably, the early time diffusive behavior of the quantum system, even when different from its classical counterpart, is stabilized by the continuous measurement process. This shows that such measurements can succeed in extracting essentially quantum effects. The transition regime studied in this paper is accessible in ongoing experiments.Comment: 8 pages, 4 figures, revtex4 (revised version contains much more introductory material

Analyse von Hyaluronsäure und Mucin5B im Speichel von Probanden mit Ektodermaler Dysplasie

Hintergrund: Probanden mit ektodermaler Dysplasie (ED) leiden an einer vererbten Störung in der Entwicklung der ektodermalen Strukturen. Sie zeigen eine deutlich reduzierte Bildung von Zähnen und Haaren sowie eine verminderte Anzahl und Aktivität von Schweiß- und Speicheldrüsen. Erst in jüngster Zeit ist die Stimme von ED-Probanden stärker in den Fokus gerückt und der subjektive Eindruck einer rauen und heiseren Stimme konnte objektiv bestätigt werden (Semmler et al. 2021). Die zugrundeliegenden Faktoren in Kehlkopf und Vokaltrakt sind noch unbekannt. Der Speichel wird bislang stellvertretend für den laryngealen Mukus untersucht. Die Rolle des Speichels/Mukus und seiner spezifischen Zusammensetzung für die resultierende Stimmqualität ist für diese seltene Krankheit und für die Stimme im Allgemeinen bisher noch ungeklärt.Material und Methoden: Eine systematische Studie wurde an 52 Probanden mit ED und 102 Kontrollpersonen (keine ED, gesunde Stimme) durchgeführt. Wir folgten dem etablierten ELS Protokoll zur Bewertung der Stimmqualität mit zusätzlicher Hochgeschwindigkeits-Videoendoskopie (HSV@4kHz). Sowohl die Video- als auch Audioaufnahmen wurden durch objektive und subjektive Messungen ausgewertet. Des Weiteren wurde eine detaillierte Laboranalyse des Ruhespeichels und des stimulierten Speichels durchgeführt.Ergebnisse: Männliche ED-Probanden wiesen im Vergleich zur Kontrollgruppe eine signifikant niedrigere Speichelproduktion und einen geringeren Mucin5B-Gehalt auf, während der Hyaluronsäurespiegel unbeeinflusst war. Zusätzlich zu der statistisch signifikant reduzierten akustischen Qualität bei ED-Probanden wurden nun auch abweichende HSV-Parameter identifiziert, die auf eine reduzierte Spannung und erhöhte Mobilität der Stimmlippen bei ED-Probanden hinweisen (Pelka et al. 2023).Diskussion: Die Beziehung zwischen laryngealem Mukus/Speichel und deren Rheologie muss weiter untersucht werden. Trotz der Seltenheit der ED können wir durch eine gründliche Untersuchung der ED-Stimme grundlegende Erkenntnisse über die Stimme im Allgemeinen gewinnen

The Mannose Receptor: From Endocytic Receptor and Biomarker to Regulator of (Meta)Inflammation

The mannose receptor is a member of the C-type lectin (CLEC) family, which can bind and internalize a variety of endogenous and pathogen-associated ligands. Because of these properties, its role in endocytosis as well as antigen processing and presentation has been studied intensively. Recently, it became clear that the mannose receptor can directly influence the activation of various immune cells. Cell-bound mannose receptor expressed by antigen-presenting cells was indeed shown to drive activated T cells towards a tolerogenic phenotype. On the other hand, serum concentrations of a soluble form of the mannose receptor have been reported to be increased in patients suffering from a variety of inflammatory diseases and to correlate with severity of disease. Interestingly, we recently demonstrated that the soluble mannose receptor directly promotes macrophage proinflammatory activation and trigger metaflammation. In this review, we highlight the role of the mannose receptor and other CLECs in regulating the activation of immune cells and in shaping inflammatory responses.Host-parasite interactio