Lepton Flavor Violation: Constraints from exotic muon to electron conversion

The exotic neutrinoless $\mu^- - e^-$ nuclear conversion is studied within the conventional extensions of the standard model as well as in the minimal supersymmetric (SUSY) models with and without R-parity conservation. The dependence of the $\mu^- - e^-$ conversion rates on the nucleon and nuclear structure is consistently taken into account. Using our calculated transition matrix elements and the available experimental data on the branching ratio $R_{\mu e^-}$ for $^{48}$Ti and $^{208}$Pb as well as the expected experimental sensitivity for $^{27}$Al employed as a target in the planned at Brookhaven $\mu^--e^-$ conversion (MECO) experiment, we extract very severe constraints for the flavor violation parameters. We especially emphasize on the constraints resulting for SUSY R-parity violating parameters.Comment: 14 pages, 2 figures. Based on the Invited talk given by T.S. Kosmas at the International Conference on Non-Accelerator New Physics(NANP'99), Dubna, Russia, 199

The role of the continuum and the spurious 1- transitions in incoherent mu - e conversion rate calculations

By using the Continuum RPA (CRPA) method, the incoherent transition strength of the exotic mu - e conversion in the 208Pb and 40Ca nuclei is investigated. The question whether excited nuclear states lying high in the continuum give an important contribution to the incoherent rate is addressed. The admixture of spurious components in the rate coming from 1- excitations is investigated in detail by using the self-consistent CRPA with Skyrme interactions as well as a less consistent version and by employing two ways to remove the spurious strength: the use of effective operators or simply the exclusion of the spurious state appearing close to zero energy. In all cases, the correction achieved is quite large

Nanomaterials responding to microwaves: an emerging field for imaging and therapy

In recent years, new microwave-based imaging, sensing and hyperthermia applications have emerged in the field of diagnostics and therapy. For diagnosis, this technology involves the application of low power microwaves, utilising contrast between the relative permittivity of tissues to identify pathologies. This contrast can be further enhanced through the implementation of nanomaterials. For therapy, this technology can be applied in tissues either through hyperthermia, which can help anti-cancer drug tumour penetration or as ablation to destroy malignant tissues. Nanomaterials can absorb electromagnetic radiation and can enhance the microwave hyperthermic effect. In this review we aim to introduce this area of renewed interest and provide insights into current developments in its technologies and companion nanoparticles, as well as presenting an overview of applications for diagnosis and therapy

Mechanisms to explain the poor results of carotid artery stenting (CAS) in symptomatic patients to date and options to improve CAS outcomes

BackgroundCarotid artery stenting (CAS) is considered by many as an alternative to carotid endarterectomy (CEA) for the management of carotid artery stenosis. However, recent trials demonstrated inferior results for CAS in symptomatic patients compared with CEA. We reviewed the literature to evaluate the appropriateness of CAS for symptomatic carotid artery stenosis and to determine the pathogenetic mechanism(s) associated with stroke following the treatment of such lesions. Based on this, we propose steps to improve the results of CAS for the treatment of symptomatic carotid stenosis.MethodsPubMed/Medline was searched up to March 25, 2010 for studies investigating the efficacy of CAS for the management of symptomatic carotid stenosis. Search terms used were “carotid artery stenting,” “symptomatic carotid artery stenosis,” “carotid endarterectomy,” “stroke,” “recurrent carotid stenosis,” and “long-term results” in various combinations.ResultsCurrent data suggest that CAS is not equivalent to CEA for the treatment of symptomatic carotid stenosis. Differences in carotid plaque morphology and a higher incidence of microemboli and cerebrovascular events during and after CAS compared with CEA may account for these inferior results.ConclusionsCurrently, most symptomatic patients are inappropriate candidates for CAS. Improved CAS technology referable to stent design and embolic protection strategies may alter this conclusion in the future

Highly Directional Scattering of Terahertz Radiation by Cylinders using Complex-Frequency Waves

In this study we investigate the directional scattering of terahertz radiation by dielectric cylinders, focusing on the enhancement of directionality using incident radiation of complex-frequency. We explore the optimization of the second Kerker condition, which corresponds to backward scattering. At first, by carefully tailoring the electric and magnetic polarizabilities of the cylinders, we successfully achieve significant backward scattering, and then manage to even further improve it by deploying a decaying incoming wave (\textit{complex}-frequency). Additionally, we present preliminary results on the directional scattering of THz radiation by a magneto-optical cylinder, demonstrating the potential of this approach for advanced control over the propagation of THz waves. Our findings contribute to a deeper understanding of THz directional scattering and pave the way for the development of novel THz devices and applications, such as high-resolution imaging, sensing, and communication systems