Spontaneous resolution of atrial and ventricular septal defects in Malta

Congenital heart disease (CHD) is the commonest congenital malformation, and ventricular septal defect (VSD) and atrial septal defect (ASD) are the commonest forms of CHD. This study was undertaken to determine rates or spontaneous closure or lesions diagnosed at echocardiography after detection or a murmur in Maltese patients born in 1990-94. A significant excess or ASD and VSD was found in Malta, and this was attributed to early echocardiographic diagnosis or small defects, prior to spontaneous closure. A high spontaneous closure rate was round for both ASD and VSD. Rate of closure for both defects was initially high, and tapered off at about 5 to 7 years or age for both lesions. ASDs in excess of 8 mm in diameter at presentation also underwent spontaneous resolution, which is contrary to the known natural history or these defects. Larger VSDs were shown to have a smaller likelihood or closing (p=0.04). Parents and patients can be reassured that spontaneous closure is very likely to occur in the vast majority of these conditions.peer-reviewe

Video codecs and decompressors

Digital video and audio produce very large and unwieldy files. Codecs are used to shrink files and them play back in reduced file size format. This article disusses the advantages, disadvantages and tradeoffs in using codes, and briefly reviews the most commonly used codecspeer-reviewe

MMR vaccination complications : is it time to lay the myth to rest?

Recent, media-hyped controversy has centred on whether there is any link between the combined measles-mumps-rubella (MMR) vaccine and autism or inflammatory bowel disease. The exhaustive available evidence fails to support any such association, yet the known high morbidity and mortality from these conditions has not prevented a small group of concerned parents from failing to vaccinate their children. This paper will outline the reasons and misconceptions behind the current MMR scare. Further efforts are necessary to completely allay the public's unfounded fears.peer-reviewe

Anderson-Witting transport coefficients for flows in general relativity

The transport coefficients induced by the Anderson-Witting approximation of the collision term in the relativistic Boltzmann equation are derived for close to equilibrium flows in general relativity. Using the tetrad formalism, it is shown that the expression for these coefficients is the same as that obtained on flat space-time, in agreement with the generalized equivalence principle.Comment: 6 pages, 1 figure, proceedings of TIM 15-16 conference (26-28 May 2016, Timisoara, Romania

Changing trends in surgery for ventricular septal defect in Malta

Congenital heart defects (CHD) comprise the commonest group of malformations and ventricular septal defect (VSD) is the most prevalent type of CHD most frequently requiring corrective surgery. There has been an increase in the number of Maltese patients operated for this condition over 1930-1994 which has now stabilised. Peri-operative mortality has declined, paralleled by a significant decline in age at surgery. The birth prevalence of VSD requiring surgery is 0.83/1000 live births with a surgical rate of 0.88 operations/1000 live births including primary operations and reoperations. Approximately 122,000 children are born with this condition annually world-wide at an estimated potential surgical cost of £2,280,000,000.peer-reviewe

Quantum non-equilibrium effects in rigidly-rotating thermal states

Based on known analytic results, the thermal expectation value of the stress-energy tensor (SET) operator for the massless Dirac field is analyzed from a hydrodynamic perspective. Key to this analysis is the Landau decomposition of the SET, with the aid of which we find terms which are not present in the ideal SET predicted by kinetic theory. Moreover, the quantum corrections become dominant in the vicinity of the speed of light surface (SOL). While rigidly-rotating thermal states cannot be constructed for the Klein-Gordon field, we perform a similar analysis at the level of quantum corrections previously reported in the literature and we show that the Landau frame is well-defined only when the system is enclosed inside a boundary located inside or on the SOL. We discuss the relevance of these results for accretion disks around rapidly-rotating pulsars.Comment: 6 pages, 2 figures, accepted for publication in Physics Letters

Transverse beam shape measurements of intense proton beams using optical transition radiation

A number of particle physics experiments are being proposed as part of the Department of Energy HEP Intensity Frontier. Many of these experiments will utilize megawatt level proton beams onto targets to form secondary beams of muons, kaons and neutrinos. These experiments require transverse size measurements of the incident proton beam onto target for each beam spill. Because of the high power levels, most beam intercepting profiling techniques will not work at full beam intensity. The possibility of utilizing optical transition radiation (OTR) for high intensity proton beam profiling is discussed. In addition, previous measurements of OTR beam profiles from the NuMI beamline are presented.Comment: 6 pp. 2nd International Conference on Technology and Instrumentation in Particle Physics 2011: TIPP2011. 9-14 Jun 2011. Chicago, Illinoi

Simple graphic manipulation

Modern graphic manipulation software is quick and simple to use, and allows medical quality graphics to be produced for online publication. This article demonstrates, step by step, how submitted images are processed by the journal in preparation for publication.peer-reviewe