We report on our analysis of a large sample of energy dependent pulse profiles of the X-ray binary pulsar Hercules X-1. We find that all data are compatible with the assumption of a slightly distorted magnetic dipole field as sole cause of the asymmetry of the observed pulse profiles. Further the analysis provides evidence that the emission from both poles is equal. We determine an angle Θ m < ...

In this work, we explore the possibility of designing photonic crystals to act as magnetic metamaterials: structures that exhibit magnetic properties despite the nonmagnetic character of their constituents. The building blocks of a magnetic material are microscopic magnetic dipoles, and to create a synthetic analog we employ point-defect modes in a photonic crystal. We begin by identifying a po...

We consider a problem in nondestructive testing in which small changes in the (possibly complex valued) refractive index n(x) of an inhomogeneous medium of compact support are to be determined from changes in measured far field data due to incident plane waves. The problem is studied by considering a modified far field operator F whose kernel is the difference of the measured far field pattern ...

The mutagenic properties of ionizing radiation are well known, but the presence of specific mutations in human radiation-induced tumours is not established. We have studied a series of 36 secondary sarcomas arising in the irradiation field of a primary tumour following radiotherapy. The allelic status and the presence of mutations of the TP53 gene were investigated. The mutation pattern was com...

Antennas are vital elements in any wireless communication systems. Radiation pattern is an important characteristic of an antenna. Radiation pattern of a single antenna element is fixed. Required radiation patterns can be generated from array of antennas. Different pattern synthesis techniques are reported in the literature. Generated patterns from selected pattern synthesis techniques can furt...

introduction: the aim of this study was to eva-luate the salivation flow rate objectively using schirmer test and mouth dryness and other con sequences subjectively by distributing question naires to patients receiving head and neck radio therapy. materials and methods: in this descriptive study that was carried out at imam khomeini hospital, tehran, iran, the saliva flow rate of 33 patients re...

In this article, a novel compact reconfigurable antenna based on substrate integrated waveguide (SIW) technology is introduced. The geometry of the proposed antennas is symmetric with respect to the horizontal center line. The electrical shape of the antenna is composed of double H-plane SIW based horn antennas and radio frequency micro electro mechanical system (RF-MEMS) actuators. The RF-MEMS...