635 resultados para Vanishing Theorems


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Die vorliegende Arbeit behandelt Vorwärts- sowie Rückwärtstheorie transienter Wirbelstromprobleme. Transiente Anregungsströme induzieren elektromagnetische Felder, welche sogenannte Wirbelströme in leitfähigen Objekten erzeugen. Im Falle von sich langsam ändernden Feldern kann diese Wechselwirkung durch die Wirbelstromgleichung, einer Approximation an die Maxwell-Gleichungen, beschrieben werden. Diese ist eine lineare partielle Differentialgleichung mit nicht-glatten Koeffizientenfunktionen von gemischt parabolisch-elliptischem Typ. Das Vorwärtsproblem besteht darin, zu gegebener Anregung sowie den umgebungsbeschreibenden Koeffizientenfunktionen das elektrische Feld als distributionelle Lösung der Gleichung zu bestimmen. Umgekehrt können die Felder mit Messspulen gemessen werden. Das Ziel des Rückwärtsproblems ist es, aus diesen Messungen Informationen über leitfähige Objekte, also über die Koeffizientenfunktion, die diese beschreibt, zu gewinnen. In dieser Arbeit wird eine variationelle Lösungstheorie vorgestellt und die Wohlgestelltheit der Gleichung diskutiert. Darauf aufbauend wird das Verhalten der Lösung für verschwindende Leitfähigkeit studiert und die Linearisierbarkeit der Gleichung ohne leitfähiges Objekt in Richtung des Auftauchens eines leitfähigen Objektes gezeigt. Zur Regularisierung der Gleichung werden Modifikationen vorgeschlagen, welche ein voll parabolisches bzw. elliptisches Problem liefern. Diese werden verifiziert, indem die Konvergenz der Lösungen gezeigt wird. Zuletzt wird gezeigt, dass unter der Annahme von sonst homogenen Umgebungsparametern leitfähige Objekte eindeutig durch die Messungen lokalisiert werden können. Hierzu werden die Linear Sampling Methode sowie die Faktorisierungsmethode angewendet.

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Die Kontroverse über den Glasübergang im Nanometerbereich, z. B. die Glas¬über¬gangs-temperatur Tg von dünnen Polymerfilmen, ist nicht vollständig abgeschlossen. Das dynamische Verhalten auf der Nanoskala ist stark von den einschränkenden Bedingungen abhängig, die auf die Probe wirken. Dünne Polymerfilme sind ideale Systeme um die Dynamik von Polymerketten unter der Einwirkung von Randbedingungen zu untersuchen, wie ich sie in dieser Arbeit variiert habe, um Einblick in dieses Problem zu erhalten.rnrnResonanzverstärkte dynamische Lichtstreuung ist eine Methode, frei von z.B. Fluoreszenzmarkern, die genutzt werden kann um in dünnen Polymerfilmen dynamische Phänomene

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The aim of this article is to disclose the characteristics of postmortem forensic imaging; give an overview of the several possible findings in postmortem imaging, which are uncommon or new to clinical radiologists; and discuss the possible pitfalls. Unspecific postmortem signs are enlisted and specific signs shall be presented, which are typical for one cause of death. Unspecific signs. Livor mortis may not only be seen from the outside, but also inside the body in the lungs: in chest CT internal livor mortis appear as ground glass opacity in the dependent lower lobes. The aortic wall is often hyperdense in postmortem CT due to wall contraction and loss of luminal pressure. Gas bubbles are very common postmortem due to systemic gas embolism after major open trauma, artificial respiration or initial decomposition; in particular putrefaction produces gas bubbles globally. Specific signs. Intracranial bleeding is hyperattenuating both in radiology and in postmortem imaging. Signs of strangulation are hemorrhage in the soft tissue of the neck like skin, subcutaneous tissue, platysma muscle and lymph nodes. The "vanishing" aorta is indicative for exsanguination. Fluid in the airways with mosaic lung densities and emphysema (aquosum) is typical for fresh-water drowning.

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Justification logics are refinements of modal logics where modalities are replaced by justification terms. They are connected to modal logics via so-called realization theorems. We present a syntactic proof of a single realization theorem that uniformly connects all the normal modal logics formed from the axioms \$mathsfd\$, \$mathsft\$, \$mathsfb\$, \$mathsf4\$, and \$mathsf5\$ with their justification counterparts. The proof employs cut-free nested sequent systems together with Fitting's realization merging technique. We further strengthen the realization theorem for \$mathsfKB5\$ and \$mathsfS5\$ by showing that the positive introspection operator is superfluous.

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Macrophage activating syndrome (MAS) is a rare hematological disorder associated with uncontrolled systemic T-cell activation. Persistent fever, fatigue and hepatosplenomegaly are frequent clinical manifestations, whereas hyperferritinemia, elevated serum lactate dehydrogenase levels and cytopenia are key criteria for the diagnosis of MAS. The nature of liver pathology in MAS has been partially elucidated but destructive biliary lesions have been rarely described. This report illustrates four cases of MAS developing marked cholestasis, leading to one case of biliary cirrhosis necessitating liver transplantation. Histologically, liver involvement was characterized in all cases by acute lobular hepatitis, marked hepatocyte apoptosis and small bile duct injury similar to the vanishing bile duct syndrome. Immuno-histological studies showed that the inflammatory changes and bile duct lesions were dominated by the presence of activated macrophages and T-cells, in particular CD8+ lymphocytes, and in part NK-cells. These findings suggest that in MAS, various T-cell triggers such as infection, autoimmune disease and malignancy might result in the release of cytokines, which in turn activate macrophages to trigger a systemic acute phase response and local tissue damage. This communication suggests that a macrophage, T- and NK-cell network is operational in the pathogenesis of the cholangiocyte, hepatocyte and sinus endothelial cell damage in MAS.

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The Great Lakes watershed is home to over 40 million people, and the health of the Great Lakes ecosystem is vital to the overall economic, societal, and environmental health of the U.S. and Canada. However, environmental issues related to them are sometimes overlooked. Policymakers and the public face the challenges of balancing economic benefits with the need to conserve and/or replenish regional natural resources to ensure long term prosperity. From the literature review, nine critical stressors of ecological services were delineated, which include pollution and contamination, agricultural erosion, non-native species, degraded recreational resources, loss of wetlands habitat, climate change, risk of clean water shortage, vanishing sand dunes, and population overcrowding; this list was validated through a series of stakeholder discussions and focus groups in Grand Rapids. Focus groups were conducted in Grand Rapids to examine the awareness of, concern with, and willingness to expend resources on these stressors. Stressors that the respondents have direct contact with tend to be the most important. The focus group results show that concern related to pollution and contamination is much higher than for any of the other stressors. Low responses to climate change result in recommendations for outreach programs.

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Chapter 1 is used to introduce the basic tools and mechanics used within this thesis. Some historical uses and background are touched upon as well. The majority of the definitions are contained within this chapter as well. In Chapter 2 we consider the question whether one can decompose λ copies of monochromatic Kv into copies of Kk such that each copy of the Kk contains at most one edge from each Kv. This is called a proper edge coloring (Hurd, Sarvate, [29]). The majority of the content in this section is a wide variety of examples to explain the constructions used in Chapters 3 and 4. In Chapters 3 and 4 we investigate how to properly color BIBD(v, k, λ) for k = 4, and 5. Not only will there be direct constructions of relatively small BIBDs, we also prove some generalized constructions used within. In Chapter 5 we talk about an alternate solution to Chapters 3 and 4. A purely graph theoretical solution using matchings, augmenting paths, and theorems about the edgechromatic number is used to develop a theorem that than covers all possible cases. We also discuss how this method performed compared to the methods in Chapters 3 and 4. In Chapter 6, we switch topics to Latin rectangles that have the same number of symbols and an equivalent sized matrix to Latin squares. Suppose ab = n2. We define an equitable Latin rectangle as an a × b matrix on a set of n symbols where each symbol appears either [b/n] or [b/n] times in each row of the matrix and either [a/n] or [a/n] times in each column of the matrix. Two equitable Latin rectangles are orthogonal in the usual way. Denote a set of ka × b mutually orthogonal equitable Latin rectangles as a k–MOELR(a, b; n). We show that there exists a k–MOELR(a, b; n) for all a, b, n where k is at least 3 with some exceptions.

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We prove analogs of classical almost sure dimension theorems for Euclidean projection mappings in the first Heisenberg group, equipped with a sub-Riemannian metric.

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Objective In order to benefit from the obvious advantages of minimally invasive liver surgery there is a need to develop high precision tools for intraoperative anatomical orientation, navigation and safety control. In a pilot study we adapted a newly developed system for computer-assisted liver surgery (CALS) in terms of accuracy and technical feasibility to the specific requirements of laparoscopy. Here, we present practical aspects related to laparoscopic computer assisted liver surgery (LCALS). Methods Our video relates to a patient presenting with 3 colorectal liver metastases in Seg. II, III and IVa who was selected in an appropriate oncological setting for LCALS using the CAScination system combined with 3D MEVIS reconstruction. After minimal laparoscopic mobilization of the liver, a 4- landmark registration method was applied to enable navigation. Placement of microwave needles was performed using the targeting module of the navigation system and correct needle positioning was confirmed by intraoperative sonography. Ablation of each lesion was carried out by application of microwave energy at 100 Watts for 1 minute. Results To acquire an accurate (less 0.5 cm) registration, 4 registration cycles were necessary. In total, seven minutes were required to accomplish precise registration. Successful ablation with complete response in all treated areas was assessed by intraoperative sonography and confirmed by postoperative CT scan. Conclusions This teaching video demonstrates the theoretical and practical key points of LCALS with a special emphasis on preoperative planning, intraoperative registration and accuracy testing by laparoscopic methodology. In contrast to mere ultrasound-guided ablation of liver lesions, LCALS offers a more dimensional targeting and higher safety control. This is currently also in routine use to treat vanishing lesions and other difficult to target focal lesions within the liver.

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Die jüdische Gemeinschaft gilt generell als Musterbeispiel einer gut integrierten, religiösen Minderheit. Tatsächlich jedoch bewirken gerade die jüngsten gesellschaftlichen Entwicklungen − verstärkte Säkularisierung und Individualisierung verbunden mit steigenden Mischehenraten und einer Neudefinitionder Geschlechterrollen − eine Infragestellung der Kontinuität europäisch-jüdischer Existenz.Seit den 70iger Jahren des 20. Jahrhunderts bewegt sich die Mischehenrate fast überall in der Diaspora bei über 50%. Da die Weitergabe des Judentums religionsgesetzlich nur über die Mutter erfolgt,stellt der Umgang mit nichtjüdischen Familienmitgliedern einen hochsensiblen Bereich für die Gemeinschaft dar. Die soziale und religiöse Integration von nichtjüdischen Ehefrauen und vaterjüdischenKindern ist auf Grund einer nicht selten willkürlich erscheinenden Aufnahmepraxis ein häufig tabuisierter Aspekt des Gemeindelebens, der zu permanenten Spannungen führt. Konflikte bezüglich der Zugehörigkeitskriterien aber auch der religiösen Rolle der Frau führen zu Polarisierungs- und Pluralisierungstendenzen. Im Rahmen eines Projektes des NFP 58 wurden aktuelle innerjüdische Grenzziehungsdebatten im Kontext des Schweizer Judentums auch mit Methoden der Oral History festgehalten und analysiert. Die Auseinandersetzungen innerhalb der schweizerisch-jüdischen Gemeinschaft wurden zudem mit Entwicklungen in anderen Ländern der Diaspora und in Israel verglichen. Es ergab sich das Bild einer dynamischen und zugleich jedoch tief gespaltenen Religionsgemeinschaft, innerhalb der sich die verschiedenen Richtungen („liberal“ bis „ultra-orthodox“) die Verantwortung für eine zunehmende Schwächung und Spaltung des jüdischen Volkes zuweisen. Bibliographie Benbassa, Esther u. Jean-Christophe Attias. 2001. Les Juifs ont-t-ils un avenir? Paris. Lattés. Gerson, Daniel.2012. Ausbreitung und Bedeutung des Judentums in der Schweiz.in : Religionen in der Schweiz. Bulletin Schweizerische Akademie der Geistes- und Sozialwissenschaften, Nr 2.Bern. Gerson, Daniel.2011. Partizipation ohne Konversion? Grenzziehungsdebatten in neuen jüdischen Gemeinschaften der Schweiz,in: Chilufim. Zeitschrift für Jüdische Kulturgeschichte, Nr.11.Wien. Phoibos. Gerson, Daniel.2010. Gemeinschaftsbildung und «demokratischer» Antisemitismus: Das Entstehen eines Schweizer Judentums im Spannungsverhältnis von Akkulturation, Einwanderung und Ausgrenzung, in: Wyrwa, Ulrich (Hrsg.): Einspruch und Abwehr. Die Reaktion des europäischen Judentums und die Entstehung des Antisemitismus in Europa. Frankfurt am Main. Campus. Lambert, Nick.2008. Jews and Europe in the Twenty-First Century. London. Vallentine Mitchell. Picard, Jacques.2007. Judentum in der Schweiz: zwischen religiöser, kultureller und politischer Identität,in: Baumann, Martin u. Jörg Stolz (Hrsg.); Eine Schweiz - viele Religionen. Bielefeld. transcript. Wasserstein, Bernard.1996. Vanishing Diaspora. The Jews in Europa since 1945. New York.Harvard University Press.

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We analyze the pion transition form factor using dispersion theory. We calculate the singly-virtual form factor in the time-like region based on data for the e+e−→3π cross section, generalizing previous studies on ω,ϕ→3π decays and γπ→ππ scattering, and verify our result by comparing to e+e−→π0γ data. We perform the analytic continuation to the space-like region, predicting the poorly-constrained space-like transition form factor below 1GeV, and extract the slope of the form factor at vanishing momentum transfer aπ=(30.7±0.6)×10−3. We derive the dispersive formalism necessary for the extension of these results to the doubly-virtual case, as required for the pion-pole contribution to hadronic light-by-light scattering in the anomalous magnetic moment of the muon.

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We generalize uniqueness theorems for non-extremal black holes with three mutually independent Killing vector fields in five-dimensional minimal supergravity in order to account for the existence of non-trivial two-cycles in the domain of outer communication. The black hole space-times we consider may contain multiple disconnected horizons and be asymptotically flat or asymptotically Kaluza–Klein. We show that in order to uniquely specify the black hole space-time, besides providing its domain structure and a set of asymptotic and local charges, it is necessary to measure the magnetic fluxes that support the two-cycles as well as fluxes in the two semi-infinite rotation planes of the domain diagram.

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We study representations of MV-algebras -- equivalently, unital lattice-ordered abelian groups -- through the lens of Stone-Priestley duality, using canonical extensions as an essential tool. Specifically, the theory of canonical extensions implies that the (Stone-Priestley) dual spaces of MV-algebras carry the structure of topological partial commutative ordered semigroups. We use this structure to obtain two different decompositions of such spaces, one indexed over the prime MV-spectrum, the other over the maximal MV-spectrum. These decompositions yield sheaf representations of MV-algebras, using a new and purely duality-theoretic result that relates certain sheaf representations of distributive lattices to decompositions of their dual spaces. Importantly, the proofs of the MV-algebraic representation theorems that we obtain in this way are distinguished from the existing work on this topic by the following features: (1) we use only basic algebraic facts about MV-algebras; (2) we show that the two aforementioned sheaf representations are special cases of a common result, with potential for generalizations; and (3) we show that these results are strongly related to the structure of the Stone-Priestley duals of MV-algebras. In addition, using our analysis of these decompositions, we prove that MV-algebras with isomorphic underlying lattices have homeomorphic maximal MV-spectra. This result is an MV-algebraic generalization of a classical theorem by Kaplansky stating that two compact Hausdorff spaces are homeomorphic if, and only if, the lattices of continuous [0, 1]-valued functions on the spaces are isomorphic.

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For patients with extensive bilobar colorectal liver metastases (CRLM), initial surgery may not be feasible and a multimodal approach including microwave ablation (MWA) provides the only chance for prolonged survival. Intraoperative navigation systems may improve the accuracy of ablation and surgical resection of so-called "vanishing lesions", ultimately improving patient outcome. Clinical application of intraoperative navigated liver surgery is illustrated in a patient undergoing combined resection/MWA for multiple, synchronous, bilobar CRLM. Regular follow-up with computed tomography (CT) allowed for temporal development of the ablation zones. Of the ten lesions detected in a preoperative CT scan, the largest lesion was resected and the others were ablated using an intraoperative navigation system. Twelve months post-surgery a new lesion (Seg IVa) was detected and treated by trans-arterial embolization. Nineteen months post-surgery new liver and lung metastases were detected and a palliative chemotherapy started. The patient passed away four years after initial diagnosis. For patients with extensive CRLM not treatable by standard surgery, navigated MWA/resection may provide excellent tumor control, improving longer-term survival. Intraoperative navigation systems provide precise, real-time information to the surgeon, aiding the decision-making process and substantially improving the accuracy of both ablation and resection. Regular follow-ups including 3D modeling allow for early discrimination between ablation zones and recurrent tumor lesions.

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Simulations of supersymmetric field theories on the lattice with (spontaneously) broken supersymmetry suffer from a fermion sign problem related to the vanishing of the Witten index. We propose a novel approach which solves this problem in low dimensions by formulating the path integral on the lattice in terms of fermion loops. For N=2 supersymmetric quantum mechanics the loop formulation becomes particularly simple and in this paper – the first in a series of three – we discuss in detail the reformulation of this model in terms of fermionic and bosonic bonds for various lattice discretisations including one which is Q-exact.