Earnings Yield and Predictability in the Dry Bulk Shipping Industry

We examine the relation between vessel prices, net earningsand holding period returns in the dry bulk shipping industry. In doing so, we provide a framework for pricing shipping assets,with finite economic lives and also subject to wear and tear.Shipping earnings yields negatively forecast future net earnings growth while there is no consistent evidence of time-varying risk premia. We provide an economic interpretation for the obtained resultsand argue that the investment decisions of shipowners affect the current price of the asset through the expectedcash flow stream,thus implying cash flow predictabilit

A young woman with renal colic presenting with urogenital anomaly: a case report

A 26-year-old female presented with a two-week history of right flank pain. She underwent abdomen ultrasound which revealed moderate pelvicalyceal dilatation in the right kidney and proximal ureter with no apparent cause. Intravenous pyelography showed a fish-hook (reversed ‘J’) shape of ureter. No renal tract calcification was noticed. The findings were consistent with that of a retrocaval ureter

Generation of ultrashort electrical pulses in semiconductor waveguides

We report a novel device capable of generating ultrashort electrical pulses on a coplanar waveguide (CPW) by means of optical rectification. The device consists of a completely passive GaAs-based optical waveguide, which is velocity matched to a CPW line. Optical pulses are injected into the device and electrical pulses are collected at the output. Experimental results obtained in the laboratory show the potential of this device for high speed optical-to-electrical conversion

Asset valuation in dry bulk shipping

This thesis examines the dry bulk sector of the shipping industry. We begin by analysing the relation between second-hand vessel prices, net earnings, and holding period returns. Specifically, we provide strong statistical evidence that almost the entire volatility of shipping earnings yields can be attributed to variation in expected net earnings growth; almost none to expected returns variation and almost none to varying expectations about the terminal earnings yield. According to our results, earnings yields are negatively and significantly related to future net earnings growth. Furthermore, we find no consistent, strong statistical evidence supporting the existence of time-varying risk premia in the valuation of dry bulk vessels. Accordingly, we integrate the examination of the second-hand market by incorporating in the analysis the trading activity related to dry bulk vessels. For this purpose, we develop a heterogeneous expectations asset pricing model that can account for the actual behaviour of vessel prices and the positive correlation between net earnings, vessel prices, and second-hand vessel transactions. The proposed economy consists of two agent types who form heterogeneous expectations about future net earnings and at the same time under(over)estimate the future demand responses of their competitors. Formal estimation of the model suggests that the average investor expectations in the second-hand market for ships must be “near-rational”. In particular, the investor population must consist of a very large fraction of agents with totally – or very close to – rational beliefs while the remaining ones must hold highly extrapolative beliefs; thus, there must exist significant heterogeneity of beliefs in the market. Having concluded the analysis of the second-hand physical shipping market we turn to the derivative market for Forward Freight Agreements (FFAs) related to the dry bulk shipping sector. Accordingly, we illustrate formally that the bulk of volatility in the FFA basis can be attributed to expectations about future physical market conditions rather than expectations about future risk premia. Despite this finding, though, we document the existence of a bias in the FFA rates in the form of “contango” but also of both a strong momentum effect and significant predictability of risk premia by price-based signals and economic variables reflecting physical market conditions. The evidence of bias is further supported by the results of three econometric tests which suggest rejection of the unbiased expectations hypothesis. Finally, to justify these findings, we develop a dynamic asset pricing framework that can incorporate both the “hedging pressure” feature and a heterogeneous-beliefs explanation

Nonlinear frequency conversion in isotropic semiconductor waveguides

This thesis describes an experimental investigation of optical frequency conversion in isotropic semiconductor waveguides by use of several phase-matching approaches. Efficient, type I second harmonic generation of femtosecond pulses is reported in birefringently-phase-matched GaAs/Alox waveguides pumped at 2.01 µm. Practical second harmonic average powers of up to ~ 650 µW are obtained, for an average launched pump power of ~ 5 mW. This corresponds to a waveguide conversion efficiency of ~ 20 % and a normalized conversion efficiency of greater than 1000 % W⁻¹cm⁻². Pump depletion of more than 80 % is recorded. Second harmonic generation by type I, third order quasi-phase-matching in a GaAs- AlAs superlattice waveguide is reported for fundamental wavelengths from ~1480 to 1520 nm. Quasi-phase-matching is achieved through modulation of the nonlinear coefficient χ[sub](zxy)⁽²⁾, which is realised by periodically tuning the superlattice bandgap. An average output power of ~25 nW is obtained for a launched pump power of <2.3 mW. Type I second harmonic generation by use of first order quasi-phase-matching in a GaAs/AlAs symmetric superlattice waveguide is also reported, with femtosecond fundamental pulses at 1.55 µm. A periodic spatial modulation of the bulk-like second- order susceptibility χ[sub](zxy)⁽²⁾ is realized using quantum well intermixing by As⁺ ion implantation. A practical second harmonic average power of ~1.5 µW is detected, for a coupled pump power of ~11 mW. Second harmonic generation through modal-phase-matching in GaAs/AlGaAs semiconductor waveguides is reported. Using femtosecond pulses, both type I and type II second harmonic conversion is demonstrated for fundamental wavelengths near 1.55 µm. An average second harmonic power of ~10.3 µW is collected at the waveguide output for a coupled pump power of <20 mW. For a complete characterisation, the optical loss is measured in these nonlinear GaAs- based waveguides over the spectral range 1.3-2.1 µm in the infrared, by deploying a femtosecond scattering technique. Typical losses of ~5-10 dB/cm are measured for the best of the waveguides, while a systematic intensity and wavelength dependent study revealed the contribution of Rayleigh scattering and two photon absorption in the overall transmission loss

Die subzelluläre Lokalisation und Wirkung auf alpha-Tubulin von Spastin und den Spastin-Mutanten K388R und S44L in eukaryotischen Zellsystemen

In der Gruppe der Hereditären Spastischen Paraplegien (HSP) stellen Mutationen im SPG4-Gen mit seinem Genprodukt Spastin die häufigste Ursache der Erkrankung dar. In dieser Arbeit wird mit GFP-Fusionsproteinen und Spastin-Antikörpern in eukaryotischen Zellsystemen die sowohl peri- wie intranukleäre Lokalisation von Spastin aufgezeigt. Daneben konnte mit Hilfe von zwei Spastin-Mutanten, K388R und S44L, sowie Antikörperfärbung von α-Tubulin, ein abbauender Effekt auf das Zellskelett beobachtet werden. Möglicherweise wirkt Spastin so regulatorisch auf das Zellskelett

Sending and receiving: immunity sought by diplomats committing criminal offences

Diplomatic immunity is one of the oldest elements of foreign relations, dating back as far as Ancient Greece and Rome. Today, it is a principle that has been codified into the Vienna Convention on Diplomatic Relations regulating past customs and practices. Consuls and international organizations, although their privileges and immunities are similar to diplomatic personnel, do differ and are regulated by the Vienna Convention on Consular Relations and the United Nations International Immunities respectively. These Conventions have been influenced by past practices and by three theories during different era’s namely exterritoriality, personal representation and functional necessity. The Vienna Convention on Diplomatic Relations further provides certain immunities and privileges to different levels of diplomatic officials, their staff and families. Privileges and immunities will be considered under various main categories, namely the diplomatic mission, the diplomatic official, diplomatic staff, and families. Each category receives privileges and immunities, for example immunities enjoyed by the diplomatic mission include mission correspondence and bags. Diplomatic officials enjoy personal inviolability, immunity from jurisdiction and inviolability of diplomats’ residences and property. The staff and families of diplomatic officials too enjoy privileges and immunities. The problem of so many people receiving privileges and immunities is that there is a high likelihood of abuse. Abuses that arise are various crimes committed by diplomats, their staff and families. They are immune from local punishment and appear to be above the local law. Although the Vienna Convention on Diplomatic Relations provides remedies against diplomats, staff and families who abuse their position, it gives the impression that it is not enough. Various Acts in the United Kingdom, United States and the Republic of South Africa will be analysed in order to ascertain what governments have done to try and curb diplomatic abuses. Each will be considered and found that although they have restricted immunity from previous practices it still places the diplomats’ needs above its own citizens. Thus several suggestions have been put forward and argued whether they are successful in restricting immunity comprehensively. Such suggestions are amending the Vienna Convention on Diplomatic Relations; using the functional necessity theory to further limit immunity; forming bilateral treaties between States as a possible means to restrict or limit; and lastly establishing a Permanent International Diplomatic Criminal Court. The key question to be answered is whether diplomatic immunity is needed for the efficient functioning of foreign relations between States

The origin of amphibole in ultramafic rocks and a new amphibole-clinopyroxene Fe-Mg exchange thermometer for mantle peridotite lithologies

Η αμφίβολος είναι μια δευτερογενής φάση που συχνά υφίσταται σε υπερμαφικές λιθολογίες (ξενολιθικοί περιδοτίτες του μανδύα, Αλπινότυποι και οφιολιθικοί περιδοτίτες) σε διάφορα περιβάλλοντα όπως μαγματικά τόξα, εσωτερικά πλακών, ρήγματα μετασχηματισμού, ζώνες διάρρηξης και σύγκρουσής. Η δημιουργία της έχει αποδοθεί είτε στην αλληλεπίδραση ρευστών/τηγμάτων με πετρώματα του μανδύα είτε στην απευθείας κρυστάλλωση από ένυδρα τήγματα. Για τον σκοπό της παρούσας εργασίας, συντέθηκε μια εκτενής βιβλιογραφική βάση δεδομένων η οποία περιλαμβάνει τις συστάσεις, σε κύρια στοιχεία, αμφιβόλων που βρίσκονται σε υπερμαφικά πετρώματα σε διαφορετικά γεωτεκτονικά περιβάλλοντα ανά τον κόσμο. Επίσης συμπεριλήφθηκαν γεωχημικά δεδομένα αμφιβόλων από ένα ευρύ φάσμα ηφαιστειακών πετρωμάτων (μαφικά έως φελσικά) τόσο σε φυσικές όσο και σε πειραματικές συνθήκες. Η μελέτη και σύγκριση των προαναφερθέντων συλλογών δεδομένων επέτρεψε την διάκριση διαφόρων τύπων αμφιβόλων καθώς και την κατανόηση της δημιουργίας των αμφιβόλων στον μανδύα. Πιο συγκεκριμένα, οι αμφίβολοι Τύπου-Ι (πλούσιες σε Na και Ti, αλλά φτωχές σε Cr) έχουνε προκύψει από την απευθείας κρυστάλλωση από βασαλτικά, βασανιτικά, ανδεσιτικά, δακιτικά τήγματα και βρίσκονται κυρίως σε ηπειρωτικά τόξα (π.χ. Καμτσάτκα, Ρωσία), περιβάλλοντα εσωτερικά των πλακών (π.χ. Δυτικό Άιφελ, Γερμανία) και ωκεάνια τόξα μετασχηματισμού (π.χ. 15°20&apos; Ζώνη Διάρρηξης, Μέσο-Ατλαντική ράχη). Οι αμφίβολοι Τύπου-ΙΙ είναι πλούσιες σε Cr και περιέχουνε διάφορα ποσοστά σε Ti και αλκάλια. Έχουνε προκύψει από την αντίδραση μεταξύ τηγμάτων και ορυκτών του μανδύα (κυρίως κλινοπυρόξενο και σπινέλιο). Βρίσκονται συνήθως σε μαγματικά κέντρα στο εσωτερικό των πλακών (π.χ. Μασίφ Σαντράλ, Γαλλία) και σε μερικά ηπειρωτικά τόξα (π.χ. Ίτσινομεγκάτα, Ιαπωνία). Οι Τύπου-ΙΙΙ αμφίβολοι αντιπροσωπεύουν την αλληλεπίδραση ένυδρων ρευστών και τηγμάτων με υπερμαφικά πετρώματα σε περιοχές ζωνών υπαγωγής και χαρακτηρίζονται από υψηλά ποσοστά σε Cr και αλκάλια, αλλά μικρό περιεχόμενο σε Ti. Οι Τύπου-ΙΙΙ αμφίβολοι εντοπίζονται σε ωκεάνια τόξα (π.χ. TUBAF, PNG), οφιολίθους (π.χ. Οφιόλιθος της Λυκίας, Τουρκία) αλλά συχνά και σε ηπειρωτικά τόξα. Επιπλέον, στην παρούσα εργασία, δημιουργήθηκε ένα θερμόμετρο ανταλλαγής Fe και Mg μεταξύ αμφιβόλου και κλινοπυροξένου το οποίο βαθμονομήθηκε σύμφωνα με προϋπάρχοντα, πειραματικά δεδομένα σε υπερμαφικές συστάσεις. Το σφάλμα του θερμομέτρου είναι ±34 °C για ένα εύρος πίεσης 0.5-3.7 GPa. Εφαρμόζοντας το θερμόμετρο σε περιδοτιτικούς ξενολίθους, που δείχνουν ενδείξεις χημικής ισορροπίας και ισορροπίας υφών μεταξύ των ορυκτών του μανδύα (π.χ. Δυτικό Άιφελ, Γερμανία; Ανατολική Τρανσυλβανική Λεκάνη, Ρουμανία), προκύπτουν θερμοκρασίες που είναι συγκρίσιμες με τη διπυροξενική θερμομετρία ανταλλαγής Fe και Mg. Το νέο θερμόμετρο μπορεί να χρησιμοποιηθεί για να περιγράψει την θερμοδυναμική ισορροπία της αμφιβόλου και του κλινοπυροξένου στον μανδύα.Amphibole is a secondary phase commonly found in ultramafic lithologies (mantle xenoliths, Alpine-type and ophiolitic peridotites) occurring in diverse environments such as magmatic arcs, plate interiors, transform faults, rifts and collision zones. Its formation has mainly been attributed to fluid-melt/rock interaction or direct crystallisation from melts/fluids. For the purpose of the present thesis, an extensive bibliographical database has been compiled. It involves major-element compositional data of amphibole in ultramafic rocks from various geotectonic settings around the globe. Additionally, amphiboles related to a wide spectrum of melts spanning from felsic to mafic in composition, both natural (rock samples) and synthetic (laboratory experiments) have also been considered. Type-I amphiboles (enriched in Na and Ti but depleted in Cr) are the products of direct crystallisation from basaltic, basanitic, andesitic and dacitic melts and are mostly found in continental arcs (e.g. Kamchatka, Russia), within-plate settings (e.g. West Eifel, Germany) and oceanic transform faults (e.g. 15°20´N Fracture Zone, Mid-Atlantic Ridge). Type-II amphiboles are Cr-rich, contain variable amounts of Ti and alkalis, and form via reaction between the aforementioned melts and primary mantle phases (mostly clinopyroxene and spinel). They are usually found in within-plate magmatic centers (e.g. Massif Central, France) and several localities in continental arcs (e.g. Ichino-megata, Japan). Amphiboles belonging to type-III reflect hydrous fluid/melt-rock interactions above subduction zones. Type-III amphiboles are predominantly encountered in oceanic arcs (e.g. TUBAF seamount, PNG) and ophiolites (Lycian ophiolite, Turkey) but occasionally they also occur in continental-arc settings. We have furthermore calibrated a new Fe Mg exchange thermometer between amphibole and clinopyroxene based on existing experimental data on ultramafic compositions with an error of ±46°C in the pressure range 0.5–3.7 GPa. Peridotite xenoliths that display good evidence of textural and chemical equilibration among their constituent minerals (e.g. West Eifel, Germany; Eastern Transylvanian Basin, Romania) yield amphibole temperatures comparable to those predicted from two-pyroxene Fe Mg exchange thermometry

The Formation of FFA Rates in Dry Bulk Shipping: Spot Rates, Risk Premia and Heterogeneous Expectations

This article examines the formation of forward rates in the dry bulk shipping industry. We illustrate that the bulk of basis volatility can be attributed to expectations about future physical market conditions rather than expectations about future risk premia. However, there exists significant predictability of risk premia by both price-based signals and economic variables. To explain this finding, we develop a dynamic asset pricing framework where, apart from having different objective functions, agents might also differ in the way they form expectations about future market conditions Accordingly, we argue that the average investor should hold “near-rational” but slightly contrarian beliefs

Asset Pricing with Mean reversion: The Case of Ships

We develop a heterogeneous-beliefsasset pricing model with microeconomic foundations that reproducesasset prices, cash flowsand tradingactivity ina real asset economy. In contrast to the majority of financial markets’ behavioural models,and in line with the nature of the shipping industry, in this model agents extrapolate fundamentals. Formal estimation of the model indicates that an economy where a small fraction of agents significantly extrapolates fundamentals can explain the positive relation between earnings, vessel prices,and trading activity