Tailoring non-classical states of light for applications in quantum information processing

In dieser Arbeit wird das Design und die Präparation von nicht-klassischen Zuständen von Licht in verschiedenen Szenarien untersucht. Zunächst wird die theoretische Beschreibung eines Interferometers entwickelt, welches für die Messung der Teilchenaustauschphase von Photonen entworfen wurde. Die Analyse der experimentellen Daten offenbart den bosonischen Charakter von Photonen, sowie die geometrische Phase, welche mit dem physischen Austausch zweier Quantenzustände assoziiert ist. Nach dieser Feststellung der Austauschsymmetrie von Zweiphotonenzuständen folgt die Ausarbeitung der Theorie über die Propagation von Mehrphotonenzuständen in Multiportsystemen. Dabei offenbaren sich hoch-dimensionale, synthetische, gekoppelte Strukturen die sich aus der Mehrphotonenanregung von diskreten Systemen ergeben. Basierend auf diesen Resultaten wird eine konkrete Anwendung der Theorie im Kontext von nicht-hermitischen Systemen formuliert. Dabei ergeben sich sogenannte “exceptional points” höherer Ordnung, welche Anwendungen im Bereich der Sensorik finden und ferner nur im Raum der Photonenanzahlzustände von diskreten Systemen realisiert werden können. Neben der Sensorik ist der Transport von Lichtzuständen ein wichtiger Aspekt in der Verarbeitung von Quanteninformationen. In dieser Hinsicht werden hier Photonische Topologische Isolatoren untersucht, welche eine rückstreuungsfreie Propagation entlang ihrer Ränder erlauben. Es wird gezeigt, dass partiell kohärentes Licht, Gaussisch und Nicht-Gaussisch verschränkte Zweiphotonenzustände einen solchen topologischen Schutz genießen können. Dies gilt unter der Vorraussetzung, dass die Anfangsanregung in einem wohldefinierten Bereich des topologischen Schutzes liegt, wodurch das “klassische” Bandlücken-kriterium erweitert und gestärkt wird.In this work we study the design and preparation of non-classical states of light in several scenarios. We begin by developing the theoretical description of an interferometer, which is designed to measure the particle exchange phase of photons. The analysis of the experimental data reveals the bosonic nature of photons, as well as the geometric phase associated with the physical exchange of the quantum states of two photons. Having established the exchange symmetry of two-photon states, we proceed to develop the theory of multi-photon states propagating in multi-port systems. We unveil the high- dimensional synthetic coupled structures that arise via the multi-photon excitation of discrete systems. Using these results, we formulate an application of the theory in the context of non-hermitian systems. We find so-called high-order exceptional points, which find applications in sensing and can only be achieved in the photon-number space of discrete systems. Apart from sensing, an important ingredient for the processing of quantum information is the transport of light states. In this regard, we consider photonic topological insulators, which allow the back-scattering-free propagation along their edges. We show that partially coherent light, Gaussian- as well as non-Gaussian two-photon entangled states can enjoy such a topological protection, provided that the initial excitations fit inside a well defined topological window of protection, which strengthens the “classical” band-gap protection criterion

Connexins and Gap Junctions in Cancer of the Urinary Tract

This review focuses on connexins and nexus or gap junctions in the genesis, progression, and therapy of carcinomas of the human urinary tract. Some decades ago, the idea was born that gap junctional intercellular communication might prevent both the onset and the progression of cancer. Later evidence indicated that, on the contrary, synthesis and the presence of connexins as a prerequisite for gap junctional intercellular communication might promote the occurrence of cancer and metastases. The research history of urinary bladder cancer is a good example of the development of scientific perception. So far, the role of gap junctional intercellular communication in carcinogenesis and cancer progression, as well as in therapeutical approaches, remains unclear

What is the clinical relevance of different lung compartments?

The lung consists of at least seven compartments with relevance to immune reactions. Compartment 1 - the bronchoalveolar lavage (BAL), which represents the cells of the bronchoalveolar space: From a diagnostic point of view the bronchoalveolar space is the most important because it is easily accessible in laboratory animals, as well as in patients, using BAL. Although this technique has been used for several decades it is still unclear to what extent the BAL represents changes in other lung compartments. Compartment 2 - bronchus-associated lymphoid tissue (BALT): In the healthy, BALT can be found only in childhood. The role of BALT in the development of the mucosal immunity of the pulmonary surfaces has not yet been resolved. However, it might be an important tool for inhalative vaccination strategies. Compartment 3 - conducting airway mucosa: A third compartment is the bronchial epithelium and the submucosa, which both contain a distinct pool of leukocytes (e.g. intraepithelial lymphocytes, IEL). This again is also accessible via bronchoscopy. Compartment 4 - draining lymph nodes/Compartment 5 - lung parenchyma: Transbronchial biopsies are more difficult to perform but provide access to two additional compartments - lymph nodes with the draining lymphatics and lung parenchyma, which roughly means "interstitial" lung tissue. Compartment 6 - the intravascular leukocyte pool: The intravascular compartment lies between the systemic circulation and inflamed lung compartments. Compartment 7 - periarterial space: Finally, there is a unique, lung-specific space around the pulmonary arteries which contains blood and lymph capillaries. There are indications that this "periarterial space" may be involved in the pulmonary host defense

Minireview and case report: Duplication of the portal vein and combinations

This is a minireview and case report on a concurrent duplication of the portal vein and a duplication of the left renal vein. The portal vein system supplies about seventy five percent of the blood for the liver and is involved in the manifestation of several liver diseases such as portal hypertension and portosystemic shunts. The vitelline veins and their anastomoses are involved in this anatomical variation during development. Similar to that also variations or malformations of the renal veins resulted from early primitive structures and their obliteration or non obliteration, respectively. Two rather rare anomalies of two venous systems might have been a coincidence or a common cause

UV-C Irradiation Reduces the Experimentally Induced Bacterial Load on the Surface of a Human Cadaver: An Additional Option for the Preservation of Cadavers in Anatomy

Safety is a major issue in the embalming procedures of human cadavers. Reduced application of formaldehyde is often recommended. The aim of this study was to investigate the potency of ultraviolet light (UV-C irradiation) on the bacterial load on the surface of a conserved human cadaver. To test UV-C irradiation, the cadaver was laid out in the dissection hall and, after preparation of the muscles, was covered with linen sheets moistened with water. Swabs of the surface and microbiological analysis revealed sporadic bacterial colonies. The surface area was then spiked with bacteria and irradiated by a UV lamp for 15 or 60 min. Half of the area was covered by aluminum foil to serve as a control. After exposition, swabs were taken and analyzed. The exposition had reduced the number of colonies to one third (15 min exposition) and to one tenth (60 min exposition) of the control area. Thus, UV-C irradiation could be used in the preservation of cadavers without chemical pollution of the environment and without any risk for the employees. Clin. Anat. 32:113–116, 2019. © 2019 The Authors. Clinical Anatomy published by Wiley Periodicals LLC on behalf of American Association of Clinical Anatomists

TRPC Channels in the Physiology and Pathophysiology of the Renal Tubular System: What Do We Know?

The study of transient receptor potential (TRP) channels has dramatically increased during the past few years. TRP channels function as sensors and effectors in the cellular adaptation to environmental changes. Here, we review literature investigating the physiological and pathophysiological roles of TRPC channels in the renal tubular system with a focus on TRPC3 and TRPC6. TRPC3 plays a key role in Ca2+ homeostasis and is involved in transcellular Ca2+ reabsorption in the proximal tubule and the collecting duct. TRPC3 also conveys the osmosensitivity of principal cells of the collecting duct and is implicated in vasopressin-induced membrane translocation of AQP-2. Autosomal dominant polycystic kidney disease (ADPKD) can often be attributed to mutations of the PKD2 gene. TRPC3 is supposed to have a detrimental role in ADPKD-like conditions. The tubule-specific physiological functions of TRPC6 have not yet been entirely elucidated. Its pathophysiological role in ischemia-reperfusion injuries is a subject of debate. However, TRPC6 seems to be involved in tumorigenesis of renal cell carcinoma. In summary, TRPC channels are relevant in multiples conditions of the renal tubular system. There is a need to further elucidate their pathophysiology to better understand certain renal disorders and ultimately create new therapeutic targets to improve patient care