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FEL Operation Modes of the MAX IV Short Pulse Facility

The Short Pulse Facility (SPF) of the MAX IV Laboratory in Lund, Sweden features the production of ultrashort, incoherent x-ray pulses. It is driven by a 3-GeV linac and comprises two 5-metre undulator modules. While the SPF is designed for spontaneous radiation, we explore alternative operation modes in which the SPF functions as a simple free-electron laser (FEL). In this article, we characteriz

Further Studies of Undulator Tapering in X-Ray FELs

We further the studies of the model-based optimization of tapered free-electron lasers presented in a recent publication [Phys. Rev. ST Accel. Beams 18, 040702 (2015)]. Departing from the ideal case, wherein the taper profile is a smooth and continuous function, we consider the more realistic case, with individual undulator segments separated by break sections. Using the simulation code GENESIS, w

Forward variance dynamics: Bergomi’s model revisited.

In this article, we propose an arbitrage-free modelling framework for the joint dynamics of forward variance along with the underlying index, which can be seen as a combination of the two approaches proposed by Bergomi. The difference between our modelling framework and the Bergomi (2008. Smile dynamics III. Risk, October, 90–96) models is mainly the ability to compute the prices of VIX futures an

Registry-based outcome assessment in haemophilia : a scoping study to explore the available evidence

Haemophilia is a congenital disorder with bleeding episodes as its primary symptom. These episodes can result in negative outcomes including joint damage, loss of active days due to hospitalization and reduced quality of life. Effective treatment, however, can improve the outcome. Registries have been used as a valuable source of information regarding the monitoring of treatment and outcome. The t

Option pricing for stochastic volatility models : Vol-of-Vol expansion

In this article, we propose an analytical approximation for the pricing of European options for some log-normal stochastic volatility models. This approximation is a second-order Taylor series expansion of the Fourier transform with respect to the “volatility of volatility.” We give, using these formulas, a new method of variance reduction for the Monte Carlo simulation of the trajectories of the

Monotonicity of Prices in Heston Model

In this article, we study the price monotonicity in the parameters of the Heston model for a contract with a convex pay-off function; in particular we consider European put options. We show that the price is increasing in the constant term in the drift of the variance process and decreasing in the coefficient of the linear term in the drift of variance process. We also show that the price is incre

Sensory qualities of the phantom hand map in the residual forearm of amputees

OBJECTIVE: Most amputees experience referred sensations, known as a phantom hand map, on the residual forearm, where touch on specific areas is perceived as touch on the amputated hand. The aim of this study was to evaluate the sensory qualities of the phantom hand map.METHODS: In 10 traumatic forearm-amputees touch thres-holds and discriminative touch of the phantom hand map were assessed and com

Parameter sensitivity of CIR process

We study the differentiability of the CIR process with respect to its parameters. We give a stochastic representation for these derivatives in terms of the paths of V.

Market making and portfolio liquidation under uncertainty

Market making and optimal portfolio liquidation in the context of electronic limit order books are of considerably practical importance for high frequency (HF) market makers as well as more traditional brokerage firms supplying optimal execution services for clients. In general, the two problems are based on probabilistic models defined on certain reference probability spaces. However, due to unce

Life History Traits of the Liverwort Herbivore Scatopsciara cunicularius (Diptera: Sciaridae)

We studied the behavior, life cycle, and reproductive biology of the sciarid fly Scatopsciara cunicularius (Lengersdorf, 1943) under two constant temperatures. The sciarid was reared at 12.3 ± 0.6°C and 22 ± 1.7°C on its host, the liverwort Marchantia polymorpha L. Our results show that the sciarid fly is able to complete its life cycle with liverwort tissue as its only source of food. The egg-lay

A novel sibling-based design to quantify genetic and shared environmental effects : application to drug abuse, alcohol use disorder and criminal behavior

BACKGROUND: Twin studies have been criticized for upwardly biased estimates that might contribute to the missing heritability problem.METHOD: We identified, from the general Swedish population born 1960-1990, informative sibships containing a proband, one reared-together full- or half-sibling and a full-, step- or half-sibling with varying degrees of childhood cohabitation with the proband. Estima

The effect of ambient temperature on larvae of Scatopsciara cunicularius (Diptera: Sciaridae) feeding on the thallose liverwort Marchantia polymorpha

Herbivory on liverworts is rarely reported. We studied the effects of feeding by larvae of the sciarid fly Scatopsciara cunicularius on the growth of the thalloid liverwort Marchantia polymorpha at two different constant temperatures, 12°C and 22°C. Larvae reared at the lower temperature fed slower and over a longer period of time, which resulted in more damage and a greater reduction in the growt

Metabolic and physiological changes in Prymnesium parvum when grown under, and grazing on prey of, variable nitrogen : Phosphorus stoichiometry

Mixotrophy is found in almost all classes of phytoplankton in a wide range of aquatic habitats ranging from oligotrophic to eutrophic marine and freshwater systems. Few studies have addressed how the nutritional status of the predator and/or the prey affects mixotrophic metabolism despite the realization that mixotrophy is important ecologically. Laboratory experiments were conducted to examine ch

Differences in substrate use efficiency : impacts of microbial community composition, land use management, and substrate complexity

Microbial substrate use efficiency is an important property in process-based soil organic matter models, but is often assumed to be constant in mechanistic models. However, previous studies question if a constant efficiency is appropriate, in particular when evaluating carbon (C) cycling across temperatures and various substrates. In the present study, we evaluated the relation between substrate u

Early postoperative haematomas in neurosurgery

Background: A postoperative haematoma can be a very serious complication following a neurosurgical procedure. Patients should be informed about the risks of such an event prior to surgery. From a practical point of view, it would be important to know when the patient is most likely to deteriorate and to require surgery because of a postoperative haematoma and when it might be safe to transfer the

Human echolocation : Acoustic gaze for burst trains and continuous noise

This study explored the ability of blind and sighted listeners to detect reflections, "echoes", of burst trains or continuous noise. Echo detection was compared by presenting 5 ms bursts, rates from 1 to 64 bursts, with a continuous white noise, all during 500 ms. Sounds were recorded in an ordinary room through an artificial binaural head, the loudspeaker 1 m behind it. The reflecting object was

A Swing Beyond Formalism: Judicial Dialogue and International Law-Shaping

The paper analyzes judicial dialogue (or judicial cross-reference) as a new form of international law-making and articulates itself around a new lexicon of international law grounded on concepts of authority, normativity and interaction, rather than sources, obligations and hierarchy in law. The aim is to offer a theoretical insight in the phenomenon of judicial cross-reference as a new avenue of