Optimal Investment Strategies and Performance Sharing Rules for Pension Schemes with Minimum Guarantee

There is a potential conflict of interest between a pension fund sponsor and future pensioners when they share unequally in the pension fund performance. Thus, when a scheme offers a yearly guaranteed minimum return to pensioners, as is presently the case with German Pensionskassen, the sponsors cannot afford to invest in risky assets and consequently, pensioners end up with safe but very low expected returns. We examine optimal investment strategies for sponsors under alternative performance sharing rules and seek the rules that are most beneficial to pensioners. We find that the current yearly performance sharing rule imposed on Pensionskassen could be tilted in favor of sponsors without impairing the welfare of pensioners. We also find that the welfare of pensioners would be greatly enhanced if the guaranteed minimum return were applied to the cumulative return since inception of the scheme rather than to yearly returns. The ensuing credit risk taken by pensioners on sponsors could be kept to a minimum by proper regulation; this would induce sponsors to adopt safe constant proportionality portfolio insurance (CPPI) style investment strategies.Private pension schemes, benefit-sharing rules, capital guaranteed products, constant mix strategies, constant proportionality portfolio insurance strategies, utility theory

Addition to the scorpion fauna of the Manaus region (Brazil), with a description of two new species of Tityus from the canopy

Two new species belonging to the genus Tityus C.L. KOCH are described from the region of Manaus, Amazonas State, Brazil. Until now a total of 9 scorpion species have been listed from this region, which is the best known region of Brazilian Amazonia. Both new species were collected from the forest canopy by means of insecticial fogging. Even though other scorpion species have previously been collected in the canopy, we suggest that the new species represent the first known examples of species living exclusively in this environment

Shaking B mediates synaptic coupling between auditory sensory neurons and the giant fiber of drosophila melanogaster

The Johnston’s Organ neurons (JONs) form chemical and electrical synapses onto the giant fiber neuron (GF), as part of the neuronal circuit that mediates the GF escape response in Drosophila melanogaster. The purpose of this study was to identify which of the 8 Drosophila innexins (invertebrate gap junction proteins) mediates the electrical connection at this synapse. The GF is known to express Shaking B (ShakB), specifically the ShakB(N+16) isoform only, at its output synapses in the thorax. The shakB2 mutation disrupts these GF outputs and also abolishes JON-GF synaptic transmission. However, the identity of the innexin that forms the presynaptic hemichannels in the JONs remains unknown. We used electrophysiology, immunocytochemistry and dye injection, along with presynaptically-driven RNA interference, to investigate this question. The amplitude of the compound action potential recorded in response to sound from the base of the antenna (sound-evoked potential, or SEP) was reduced by RNAi of the innexins Ogre, Inx3, Inx6 and, to a lesser extent Inx2, suggesting that they could be required in JONs for proper development, excitability, or synchronization of action potentials. The strength of the JON-GF connection itself was reduced to background levels only by RNAi of shakB, not of the other seven innexins. ShakB knockdown prevented Neurobiotin coupling between GF and JONs and removed the plaques of ShakB protein immunoreactivity that are present at the region of contact. Specific shakB RNAi lines that are predicted to target the ShakB(L) or ShakB(N) isoforms alone did not reduce the synaptic strength, implying that it is ShakB(N+16) that is required in the presynaptic neurons. Overexpression of ShakB(N+16) in JONs caused the formation of ectopic dye coupling, whereas ShakB(N) prevented it altogether, supporting this conclusion and also suggesting that gap junction proteins may have an instructive role in synaptic target choice

Pneumo-thorax/mediastinum/(retro)peritoneum/ scrotum a full house of complications following JET ventilation

Presentiamo il caso di un paziente che è giunto alla nostra clinica per unostruzione respiratoria secondaria a un carcinoma orofaringeo. Il paziente è stato sottoposto a una tracheotomia in emergenza e a una ventilazione JET, che ha dato come conseguenza un insieme di complicanze barotraumatiche, fra le quali un pneumotorace, penumomediastino, pneumoperitoneo, pneumoretroperitoneo, e pneumoscroto. Tale tipologia di ventilazione, benché talvolta dalle conseguenze drammatiche, come nel nostro caso, non è per questo necessariamente da temere e può essere ben gestita. Il nostro paziente è stato trattato con un drenaggio toracico ed è andato incontro a un recupero completo

Cervical emphysema: an unusual presentation of laryngeal cancer

Abstract Background: Acute respiratory decompensation can occur on a background of slowly progressive airway compromise, for example in laryngeal squamous cell cancer. Surgeons in ENT, together with anaesthetists, are often asked to evaluate airway risk and as yet there is no widely adopted standardised approach. Case report: This paper reports the case of an 82-year-old male, who presented with acute airway compromise due to both endolaryngeal obstruction from a squamous cell cancer and extralaryngeal compression from massive subcutaneous emphysema. Results: Primary total laryngectomy was performed, but the patient declined adjuvant radiotherapy. He died a year later from a heart attack without evidence of recurrence. Conclusion: To the best of our knowledge, this is the first case report of acute airway compromise from extralaryngeal subcutaneous emphysema secondary to laryngeal cancer. Options for acute airway management are discusse

Delayed granulomatous reaction to hyaluronic acid gel injection

Injectable hyaluronic acid (HA) derivatives are the most used resorbable dermal fillers used for soft tissue augmentation. While their use is considered safe, there have been reports of cutaneous granulomatous reactions. We describe the clinical, radiological, and cytological findings in a patient who presented a full year after cosmetic treatment with HA injections and discuss the various treatment options. Level of Evidence: Level V, therapeutic study

: Bilan de la campagne 2005.

Rapport de mission illustré (cartes, plans, photographies).This report describes the excavations at Termez, in the fortification of Tchingiz Tepe ; in the temple and the citadel.Ce rapport décrit les fouilles de Termez, sur les fortifications du Tchingiz Tepe 5 ; du complexe cultuel et de la citadelle

Diversification with volatility products

Recent changes to clearing-house regulations have promoted exchange-traded products offering risk premia previously accessible only over-the-counter. Thus, as correlations increase between equity, bonds and commodities, a new strand of research questions the benefits of home-grown diversification using volatility products. First we ask: “What expected returns will induce equity and bond investors to perceive ex-ante diversification benefits from adding volatility?” We call this the optimal diversification threshold. We derive the theoretical thresholds for minimum-variance, mean-variance and Black–Litterman optimization. Empirical analysis of US and European markets shows that volatility diversification is frequently perceived to be optimal, ex-ante, but these apparent benefits are almost never realized, being eroded by high roll and transaction costs. Exchange-traded volatility only proved an effective diversifier during the banking crisis. At other times long equity and bond portfolios diversified with volatility futures have not performed as well as those without diversification, or even those diversified with commodities

A novel lineage of candidate pheromone receptors for sex communication in moths

Sex pheromone receptors (PRs) are key players in chemical communication between mating partners in insects. In the highly diversified insect order Lepidoptera, male PRs tuned to female-emitted type I pheromones (which make up the vast majority of pheromones identified) form a dedicated subfamily of odorant receptors (ORs). Here, using a combination of heterologous expression and in vivo genome editing methods, we bring functional evidence that at least one moth PR does not belong to this subfamily but to a distantly related OR lineage. This PR, identified in the cotton leafworm Spodoptera littoralis, is highly expressed in male antennae and is specifically tuned to the major sex pheromone component emitted by females. Together with a comprehensive phylogenetic analysis of moth ORs, our functional data suggest two independent apparitions of PRs tuned to type I pheromones in Lepidoptera, opening up a new path for studying the evolution of moth pheromone communication

Computational Model of the Insect Pheromone Transduction Cascade

A biophysical model of receptor potential generation in the male moth olfactory receptor neuron is presented. It takes into account all pre-effector processes—the translocation of pheromone molecules from air to sensillum lymph, their deactivation and interaction with the receptors, and the G-protein and effector enzyme activation—and focuses on the main post-effector processes. These processes involve the production and degradation of second messengers (IP3 and DAG), the opening and closing of a series of ionic channels (IP3-gated Ca2+ channel, DAG-gated cationic channel, Ca2+-gated Cl− channel, and Ca2+- and voltage-gated K+ channel), and Ca2+ extrusion mechanisms. The whole network is regulated by modulators (protein kinase C and Ca2+-calmodulin) that exert feedback inhibition on the effector and channels. The evolution in time of these linked chemical species and currents and the resulting membrane potentials in response to single pulse stimulation of various intensities were simulated. The unknown parameter values were fitted by comparison to the amplitude and temporal characteristics (rising and falling times) of the experimentally measured receptor potential at various pheromone doses. The model obtained captures the main features of the dose–response curves: the wide dynamic range of six decades with the same amplitudes as the experimental data, the short rising time, and the long falling time. It also reproduces the second messenger kinetics. It suggests that the two main types of depolarizing ionic channels play different roles at low and high pheromone concentrations; the DAG-gated cationic channel plays the major role for depolarization at low concentrations, and the Ca2+-gated Cl− channel plays the major role for depolarization at middle and high concentrations. Several testable predictions are proposed, and future developments are discussed