Channel Models for Medical Implant Communication

Information regarding the propagation media is typically gathered by conducting physical experiments, measuring and processing the corresponding data to obtain channel characteristics. When this propagation media is human body, for example in case of medical implants, then this approach might not be practical. In this paper, an immersive visualization environment is presented, which is used as a scientific instrument that gives us the ability to observe RF propagation from medical implants inside a human body. This virtual environment allows for more natural interaction between experts with different backgrounds, such as engineering and medical sciences. Here, we show how this platform has been used to determine channel models for medical implant communication systems.     

Ultra wideband antenna

Ultra wideband antennas are specifically designed to transmit and/or receive very short time durations of electromagnetic energy. It is well known that UWB antenna design remains the major factor in the progress of UWB technology. This article describes a study of conventional antennas and why they are not suitable for a UWB system.     

Wireless Technologies in Healthcare: Selected Papers from IEEE PIMRC 2011

The use of wireless technologies for medical device communication, health monitoring (at hospitals or homes) and mobile healthcare information delivery (i.e. m-Health) is one of the most rapidly growing areas in health-IT research today. The papers which appear in this special issue have been carefully selected from the best IEEE PIMRC 2011 conference. They are highlighting various challenging issues in using wireless technology for healthcare applications such as PHY & MAC innovations for wearable and implantable medical sensors, optical communication and location systems in hospital environments and interference mitigation issues.     

Body Area Networking: Selected Papers from IEEE PIMRC 2009

Body Area Networks (BAN) which consist of RF-enabled wearable and implantable sensory nodes are poised to be a promising interdisciplinary technology with novel uses in pervasive healthcare, personal entertainment and consumer electronics. The papers which appear in this special issue have been carefully selected from the best IEEE PIMRC 2009 conference papers addressing some of the most challenging issues in BAN such as propagation modeling, physical, and medium access control layers. Papers presented here propose models, algorithms and protocols exhibiting advance research in this promising field.     

Revisiting the effects of sequence and structure on the hydrogen bonding and π-stacking interactions in nucleic acids

Calculated electron densities from PBE0/6-31+G(d,p) were analyzed with respect to the hydrogen bonding within a nucleic acid base pair and the π-stacking between sets of base pairs. From published X-ray crystallographic data, base pairs were isolated from a total of 11 DNA and RNA duplexes, and their experimental geometry was maintained throughout the analyses. Focusing solely on Watson-Crick base pairs, from the values of the electron density between interacting nuclei (at the bond critical points), we provide quantitative data on individual weak interactions. For hydrogen bonding, in addition to quantifying the scissoring effect in GC base pairs, the origin of the controversy around the relative stability of AT and AU base pairs is identified and resolved. Thus, it is illustrated how the conclusion as to their relative stability rests on the specific choice of oligonucleotides compared. For π-stacking, sequence effects for tandem AT base pairs are captured, quantified, and explained, and the greater sensitivity of GC, over AT, sequences to the rise parameter is established. The results presented here show that, from experimental geometries and their electron densities, previously determined effects of the sequence and structure of a duplex on the stabilizing interactions can be captured, quantified, and traced back to the geometry of the base pairs.