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Gli isolanti topologici sono materiali che recentemente stanno attirando molta attenzione da parte della comunità scientifica, sono caratterizzati da un bulk isolante e da delle superfici sulle quali invece sono presenti degli stati topologici 2D. Sono caratterizzati da una struttura a bande a cono di Dirac, garantendo quindi una elevata mobilità dei portatori e la presenza di una polarizzazione di spin in funzione del momento elettronico. Tale associazione fra spin e momento dei portatori si traduce nel fatto che dipendentemente dalla direzione della corrente imposta nel materiale si crea una polarizzazione superficiale. Essendo tale fenomeno invertibile (imponendo una polarizzazione superficiale si genera una corrente nel materiale) tali materiali possono essere usati come convertitori carica-spin e viceversa, garantendo in entrambi i casi un basso consumo di energia e una elevata velocità. Per questi motivi gli isolanti topologici risultano degli ottimi candidati per rendere più efficienti alcuni dispositivi presenti nell’elettronica tradizionale fra cui le memorie e le logiche. Al momento gli isolanti topologici sono cresciuti principalmente tramite MBE e tale tecnica di crescita non è compatibile con gli standard industriali, per via degli elevati costi che sarebbero necessari per supportare una produzione di massa. Risulta quindi importante ottimizzare dei processi di crescita meno costosi e compatibili con il mondo dell’industria per favorire il trasferimento di tale tecnologia nel campo della microelettronica tradizionale, come ad esempio i processi basati sulla metal-organic chemical vapor depositioin (MOCVD). In questa tesi vengono caratterizzati film sottili di Sb2Te3, Bi2Te3 e di un bilayer composto da Sb2Te3/Bi2Te3 cresciuti tramite MOCVD su wafer intrinseci di Si(111) larghi 4 ‘’. L'obiettivo è stato quello di convalidare il comportamento topologico di questi materiali cresciuti tramite MOCVD con particolare attenzione alla verifica delle loro proprietà funzionali elettroniche e magnetiche. L’esistenza delle superfici topologiche in questi materiali è stata studiata tramite l’analisi delle proprietà magnetoelettriche, usando il modello di HLN e tramite l’osservazione della struttura a banda fatta utilizzando angle-resolved photoemission spettroscopy (ARPES). Abbiamo verificato che in tutti gli isolanti topologici che abbiamo cresciuto, il trasporto viene parzialmente supportato da elettroni appartenenti agli stati topologici e parzialmente supportato da elettroni appartenenti a stati di bulk, quindi privi di elevata mobilità e di proprietà magnetiche. Tale contributo alla conduzione dagli stati di bulk si è particolarmente impattante nel Bi2Te3 e ciò è dovuto al fatto che il livello di Fermi si trova in corrispondenza delle bande di conduzione del bulk. Abbiamo dunque modificato la posizione del livello di Fermi nel Bi2Te3 crescendolo al di sopra di un campione di Sb2Te3, sempre tramite MOCVD. Mediante ARPES, abbiamo verificato un chiaro spostamento del livello di Fermi verso il punto di Dirac riducendo drasticamente il contributo degli stati di bulk alla conduzione. I due materiali con la struttura a bande più vicina a quella di un isolante topologico ideale, ovvero Sb2Te3 e Sb2Te3/Bi2Te3 sono stati utilizzati per stimarne l’efficienza di conversione spin-carica quando posti al di sotto di un ferromagnete (Co). Entrambi hanno dimostrato una efficienza di conversione comparabile se non maggiore rispetto a quella di materiali cresciuti con MBE, quindi validando a pieno la loro funzionalità. In ultima istanza sono stati cresciuti dei film 2D ferromagnetici basati sulla lega CrTe, su tutti gli isolanti topologici fabbricati tramite MOCVD. Il loro comportamento magnetico è stato verificato tramite microscopia MOKE costituendo un primo passo verso la realizzazione di dispositivi spintronici basati sull’integrazione di tali materiali sugli isolanti topologici cresciuti con MOCVD. Chalcogenide thin films, such as Bi2Te3 and Sb2Te3 have been under the scientific community’s attention since long, due to their application as thermoelectric material. Recently, they are gaining additional interest because of their potential use as Topological Insulators (TIs). TIs are materials that combine the existence of insulating bulk with the presence of surfaces hosting Topological Surface States (TSS). TSS are characterized by a Dirac-like band structure with intrinsic momentum-dependent spin polarization and extremely high mobility. These features translate into the possibility of controlling the magnetization of an adjacent magnetic media by applying an electric field across the TI (charge-to-spin conversion) or vice versa (spin-to-charge conversion), in both cases with very low electrical dissipation and limited operation time. Because of these astonishing electrical properties, they have been proposed as potential materials to boost the integration of spintronic devices into ordinary electronics. However, the main currently used technique to grow TIs is Molecular Beam Epitaxy, which is not suitable to guarantee the TIs’ mass production, mainly due to the high cost to be faced when targeting wafers-scaled growth. Achieving the growth of TIs through methods allowing an easier technology transfer is therefore demanding. Among them, chemical methods are thought to be a good solution to achieve conformal TIs’ growth on large-area substrates, at a limited cost. In this thesis, I used metal-organic chemical vapor deposition (MOCVD) to optimize the growth of p-type Sb2Te3, n-type Bi2Te3, and combined Sb2Te3/Bi2Te3 bilayer, on top of Si(111) intrinsic substrate. The main focus has been to validate the topological behavior of such large-area TIs by a thorough study of their (magneto) electrical and electronic properties. In all cases, the clear existence of TSS has been demonstrated by analyzing the observed weak-antilocalization (WAL) effect and by imaging the band structure with angle-resolved photoemission spectroscopy (ARPES). In all the TIs, there is the existence of a non-negligible contribution to the global transport mechanism arising from the bulk states. This is particularly true in the Bi2Te3 single layers, due to the Fermi level crossing the bulk states. A core activity of the thesis’s work was therefore dedicated to attempt the Bi2Te3’s band structure engineering by coupling it with Sb2Te3 in a full in-situ MOCVD process. In particular, with Sb2Te3 and Bi2Te3 sharing the same crystalline structure, the growth of Bi2Te3 on top of Sb2Te3 was optimized. By ARPES, we observed a clear shift of the Fermi level towards the Dirac point. As a direct consequence, the bulk contribution to the global transport mechanism is largely suppressed, and this is reflected in MC shape which is very close to the cusp-like one expected for ideal TIs where the bulk is insulating. The MOCVD-developed TIs has been finally integrated in simple heterostructures with simple (Co-based) ferromagnetic layers, in order to test their potentiality as spin-charge converters. In particular, by means of spin-pumping ferromagnetic resonance (SP-FMR), the spin-charge conversion occurring in Sb2Te3 and the bilayer of Sb2Te3/Bi2Te3 has been measured by taking advantage of the clear favorable position of the Fermi level close to the Dirac point. For both systems, SP-FMR demonstrated quite a large spin-charge conversion, thus confirming that the MOCVD-grown Si/Sb2Te3 and Si/Sb2Te3/Bi2Te3 are promising candidates to be integrated into future spintronic devices based on TIs. The successful growth of the 2D ferromagnet CrTe-based alloy on top of our MOCVD-grown TIs has also been achieved, and the magnetic properties of the 2D ferromagnets were verified by MOKE microscopy, constituting a first step towards the development of a full chalcogenide-based spin-charge converter.

This is the first study to look at the characteristics of funds accepting the $2.7 trillion taxpayer guarantee of money market mutual funds during the 2008 financial crisis. Fund shares that benefited from Federal Reserve’s asset-backed commercial paper program were significantly more likely to get bailed out by taxpayers and sponsors. The paper tests if funds adhering to the SEC’s 2010 liquidity reforms prior to their enactment were less likely to be bailed out in 2008. Finally, it examines if funds subject to the 2014 floating NAV regulations were more likely to be bailed out in 2008.

Pb-isotopes have been proposed as pathfinders for sandstone-hosted unconformity-related U deposits, with isotope ratios providing information on mineralization timing and element remobilization and migration. Pb-isotopes proximal to mineralization display radiogenic signatures, often with &lsquo, excess Pb&rsquo, suggestive of derivation from greater U concentrations than are currently present. The U deposits in the Kiggavik project area (west of Baker Lake, NU, Canada) are basement-hosted, contain several generations of pitchblende mineralization, display a strong structural control, and are located in fault-related fracture systems and foliation-parallel veinlets. Drill core samples were analysed by Inductively-Coupled Plasma-Mass Spectrometer (ICP-MS) for Pb isotopes following multi-acid total-digestion, reverse Aqua Regia partial-digestion, and weak-acid-leach attacks, to evaluate the utility of the respective dissolution methods in Pb-isotope pathfinder geochemistry. Partial-digestion results are similar to weak-acid-leach results, indicating that interpretation of Pb-isotope signatures can be carried out from partial-digestion data if weak-acid-leach data are unavailable. Application of this pathfinder method at Kiggavik shows that Pb-isotope ratios display systematic trends useful for exploration vectoring. Uranium-content-adjusted 206Pb/204Pb ratios and 206Pb/204Pb &lsquo, excess-lead&rsquo, data highlight anomalous isotopic values. 207Pb/206Pb ratios display downhole trends complementary to location of mineralization. Three-dimensional (3D) distributions of Pb-isotope data at the Contact U prospect show systematic trends and form halos around the mineralization. Isotopic footprints are limited to &lt, 50 m from the mineralization outline, reflecting host-rock and structural control, but indicate areas with elevated potential for U mineralization and provide vectoring information within basement lithologies.

Endogenous sharing rules were introduced by Simon and Zame (Econometrica 58(4):861–872, 1990) to model payoff indeterminacy in discontinuous games. They prove the existence in every compact strategic game of a mixed Nash equilibrium and an associated sharing rule. We extend their result to economies with externalities (Arrow and Debreu in Econometrica 22(3):265–290, 1954) where, by definition, players are restricted to pure strategies. We also provide a new interpretation of payoff indeterminacy in Simon and Zame’s model in terms of preference incompleteness.

The range of substrates that the bone-eating marine worm Osedax is able to consume has important implications for its evolutionary history, especially its potential link to the rise of whales. Once considered a whale specialist, recent work indicates that Osedax consumes a wide range of vertebrate remains, including whale soft tissue and the bones of mammals, birds and fishes. Traces resembling those produced by living Osedax have now been recognized for the first time in Oligocene whale teeth and fish bones from deep-water strata of the Makah, Pysht and Lincoln Creek formations in western Washington State, USA. The specimens were acid etched from concretions, and details of the borehole morphology were investigated using micro-computed tomography. Together with previously published Osedax traces from this area, our results show that by Oligocene time Osedax was able to colonize the same range of vertebrate remains that it consumes today and had a similar diversity of root morphologies. This supports the view that a generalist ability to exploit vertebrate bones may be an ancestral trait of Osedax. peerReviewed

Einleitung: Seit der Erstbeschreibung durch Thorek 1930 haben sich sowohl die Operationstechniken der Oberarm-, aber auch die der Oberschenkelstraffung ständig weiterentwickelt und verfeinert, um zum einen die Komplikationsrate zu senken, aber auch um die Ergebnisse zu optimieren. Wir berichten[zum vollständigen Text gelangen Sie über die oben angegebene URL], 46. Jahrestagung der Deutschen Gesellschaft der Plastischen, Rekonstruktiven und Ästhetischen Chirurgen (DGPRÄC), 20. Jahrestagung der Vereinigung der Deutschen Ästhetisch-Plastischen Chirurgen (VDÄPC)

Hintergrund: Der Gesäßbereich hat hervorragende Voraussetzungen für den Eigenfetttransfer- Der hohe Anteil an Muskelgewebe stellt ein sehr gut perfundiertes Empfängerbett da und erklärt die hervorragenden Erfolgsraten des Fetttransfers in der Gesässregion. Ziel[zum vollständigen Text gelangen Sie über die oben angegebene URL], 46. Jahrestagung der Deutschen Gesellschaft der Plastischen, Rekonstruktiven und Ästhetischen Chirurgen (DGPRÄC), 20. Jahrestagung der Vereinigung der Deutschen Ästhetisch-Plastischen Chirurgen (VDÄPC)

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Eine grundlegend neue Methode d. Fettabsaugung wird vorgestellt, bei der eine Doppellumenkanüle eíngesetzt wird. Das Gewebe wird mit Kochsalzlösung unter hohem Druck angespült, wodurch die Fettzellen aus ihrem Verband gelöst werden. Simultanes Absaugen von Spüllösung u. Fett. Vorteile:*Operations-u. Narkosedauer verringern sich erheblich ; zeitraubende Instillation von Tumeszenzlösung entfällt *Methode macht direkte Begutachtung des Operationserfolges möglich *Die Besonderheit der Methode erlaubt ein Lösen von Zellverbänden u.deren Umverteilung i.S. einer Modellierung der Körperoberfläche *Die losgelösten Zellverbände bleiben vital u. eignen sich aufgrund ihrer Grösse zu Fettgewebs-Transplantationen "Lipofillings". Die Doppellumen-Kanüle wurde als Gebrauchsmuster Nr.200 09 785.5 beim Dtsch.Patentamt eingetragen. Die vorliegende Arbeit beschreibt die Entwicklung der Methode u. ihre Anwendung an über 200 Patienten.