Quantum chaos with complex, non-periodic orbits

We show that special types of orbits, which are nonperiodic and complex “saddle orbits” (SOs), describe accurately the quantal and experimental current oscillations in the resonant tunneling diode in tilted fields. The SOs solve the puzzle of broad regions of experimental oscillations where we find no real or complex periodic orbit (PO) that can explain the data. The SOs succeed in regimes involving several nonisolated POs, where PO formulas fail. We show that their contribution can, unexpectedly, decay very slowly in the classical limit

The linear dependence relations and truncation errors for interpolating even order splines

Linear dependence relations are derived for even order polynomial splines defined over the points midway between a uniformly spaced set of knots. The leading term of the truncation error is determined and is illustrated by an example

Enabling Confidentiality in Content-Based Publish/Subscribe Infrastructures

Content-Based Publish/Subscribe (CBPS) is an interaction model where the interests of subscribers are stored in a content-based forwarding infrastructure to guide routing of notifications to interested parties. In this paper, we focus on answering the following question: Can we implement content-based publish/subscribe while keeping subscriptions and notifications confidential from the forwarding brokers? Our contributions include a systematic analysis of the problem, providing a formal security model and showing that the maximum level of attainable security in this setting is restricted. We focus on enabling provable confidentiality for commonly used applications and subscription languages in CBPS and present a series of practical provably secure protocols, some of which are novel and others adapted from existing work. We have implemented these protocols in SIENA, a popular CBPS system. Evaluation results show that confidential content-based publish/subscribe is practical: A single broker serving 1000 subscribers is able to route more than 100 notifications per second with our solutions

Non-Hodgkin’s Lymphoma of the Uterine Cervix

Non Hodgkin’s Lymphoma (NHL) causes many deaths worldwide and its incidence is increasing. They occur commonly in middle aged and elderly people and are disseminated at diagnosis. We present an interesting case of NHL in a 52 years old female, who presented with past a history of postmenopausal bleeding. A 3 x 5 cms endocervical polyp was noticed in the cervix. Biopsy of the polyp revealed it to be a CD20-positive diffuse large B-cell (DLBCL)-type NHL. She was diagnosed as stage IE after staging work-up. She attained a complete response, and has been in remission for 1 year 8 months

The Clinical Significance of Subclinical Thyroid Dysfunction.

Subclinical thyroid disease (SCTD) is defined as serum free T(4) and free T(3) levels within their respective reference ranges in the presence of abnormal serum TSH levels. SCTD is being diagnosed more frequently in clinical practice in young and middle-aged people as well as in the elderly. However, the clinical significance of subclinical thyroid dysfunction is much debated. Subclinical hyper- and hypothyroidism can have repercussions on the cardiovascular system and bone, as well as on other organs and systems. However, the treatment and management of SCTD and population screening are controversial despite the potential risk of progression to overt disease, and there is no consensus on the thyroid hormone and thyrotropin cutoff values at which treatment should be contemplated. Opinions differ regarding tissue effects, symptoms, signs, and cardiovascular risk. Here, we critically review the data on the prevalence and progression of SCTD, its tissue effects, and its prognostic implications. We also examine the mechanisms underlying tissue alterations in SCTD and the effects of replacement therapy on progression and tissue parameters. Lastly, we address the issue of the need to treat slight thyroid hormone deficiency or excess in relation to the patient's ag

Virtual photons, dipole fields and energy transfer: a quantum electrodynamical approach

Dipole emission mechanisms for energy transfer operate in many important areas of photophysics. A straightforward analysis based on quantum electrodynamics not only reveals the entanglement of mechanisms usually regarded as 'radiative' and 'radiationless'; it also gives significant physical insights into a host of topics in electromagnetism. These include: the designation of real and virtual photons; propagating and non-propagating character in electromagnetic fields; near-zone and wave-zone effects; transverse and longitudinal character; the effects of retardation; the relation between couplings of static and transition dipoles, and manifestations of quantum uncertainty. A simple extension of the theory to accommodate magnetic dipole as well as electric dipole transitions furthermore reveals key differences between the range dependences of the magnetic and electric fields produced by dipolar emission. With important technological applications, this lesson in advanced physics showpieces the interplay of principles associated with quantum mechanics, electromagnetism and photophysics

Optimum projection angle for attaining maximum distance in a soccer punt kick

Copyright @ Journal of Sports Science and Medicine 2011.This article has been made available through the Brunel Open Access Publishing Fund.To produce the greatest horizontal distance in a punt kick the ball must be projected at an appropriate angle. Here, we investigated the optimum projection angle that maximises the distance attained in a punt kick by a soccer goalkeeper. Two male players performed many maximum-effort kicks using projection angles of between 10 degrees and 90 degrees. The kicks were recorded by a video camera at 100 Hz and a 2-D biomechanical analysis was conducted to obtain measures of the projection velocity, projection angle, projection height, ball spin rate, and foot velocity at impact. The player's optimum projection angle was calculated by substituting mathematical equations for the relationships between the projection variables into the equations for the aerodynamic flight of a soccer ball. The calculated optimum projection angles were in agreement with the player's preferred projection angles (40 degrees and 44 degrees). In projectile sports even a small dependence of projection velocity on projection angle is sufficient to produce a substantial shift in the optimum projection angle away from 45 degrees. In the punt kicks studied here, the optimum projection angle was close to 45 degrees because the projection velocity of the ball remained almost constant across all projection angles. This result is in contrast to throwing and jumping for maximum distance, where the projection velocity the athlete is able to achieve decreases substantially with increasing projection angle and so the optimum projection angle is well below 45 degrees.This article is made available through the Brunel University Open Access Publishing Fund

A Historical Perspective on Runtime Assertion Checking in Software Development

This report presents initial results in the area of software testing and analysis produced as part of the Software Engineering Impact Project. The report describes the historical development of runtime assertion checking, including a description of the origins of and significant features associated with assertion checking mechanisms, and initial findings about current industrial use. A future report will provide a more comprehensive assessment of development practice, for which we invite readers of this report to contribute information