Edinburgh Napier University

About: Edinburgh Napier University is a education organization based out in Edinburgh, United Kingdom. It is known for research contribution in the topics: Population & Health care. The organization has 2665 authors who have published 6859 publications receiving 175272 citations.

Metamaterial-Inspired Antenna Array for Application in Microwave Breast Imaging Systems for Tumor Detection

Abstract: This paper presents a study of a planar antenna-array inspired by the metamaterial concept where the resonant elements have sub-wavelength dimensions for application in microwave medical imaging systems for detecting tumors in biological tissues. The proposed antenna consists of square-shaped concentric-rings which are connected to a central patch through a common feedline. The array structure comprises several antennas that are arranged to surround the sample breast model. One antenna at a time in the array is used in transmission-mode while others are in receive-mode. The antenna array operates over 2–12 GHz amply covering the frequency range of existing microwave imaging systems. Measured results show that compared to a standard patch antenna array the proposed array with identical dimensions exhibits an average radiation gain and efficiency improvement of 4.8 dBi and 18%, respectively. The average reflection-coefficient of the array over its operating range is better than S11 ≤ −20 dB making it highly receptive to weak signals and minimizing the distortion encountered with the transmission of short duration pulse-trains. Moreover, the proposed antenna-array exhibits high-isolation on average of 30dB between radiators. This means that antennas in the array (i) can be closely spaced to accommodate more radiators to achieve higher-resolution imaging scans, and (ii) the imagining scans can be done over a wider frequency range to ascertain better contrast in electrical parameters between malignant tumor-tissue and the surrounding normal breast-tissue to facilitate the detection of breast-tumor. It is found that short wavelength gives better resolution. In this experimental study a standard biomedical breast model that mimics a real-human breast in terms of dielectric and optical properties was used to demonstrate the viability of the proposed antenna over a standard patch antenna in the detection and the localization of tumor. These results are encouraging for clinical trials and further refinement of the antenna-array.

Use of a Phytoplankton Community Index to assess the health of coastal waters

Abstract: Tett, P., Carreira, C., Mills, D. K., van Leeuwen, S., Foden, J., Bresnan, E., and Gowen, R. J. 2008. Use of a Phytoplankton Community Index to assess the health of coastal waters. - ICES Journal of Marine Science, 65: 1475-1482.Monitoring of marine-ecosystem status and health requires indicators of community structure and function. As a structural indicator, we propose a Phytoplankton Community Index (PCI) based on the abundance of “life-forms” such as “pelagic diatoms” or “medium-sized autotrophic dinoflagellates”. To calculate the PCI, data showing seasonal variation in these abundances are plotted in “life-form space” of two or more dimensions. Data from a “type-specific reference condition” are then enclosed within a reference envelope. Comparison data are plotted into the same coordinate system, and the PCI is the proportion (between 0 and 1) of these new data that fall within the reference envelope. Results from initial applications of this method are shown for UK coastal waters in the northern North Sea (near Stonehaven), a Scottish fjord (Loch Creran), and the eastern Irish Sea (including Liverpool Bay). The Stonehaven data (1997-2005) were used to compare values obtained from weekly sampling with those from monthly sampling. A spatial comparison between more- and less-nutrient-enriched waters in the eastern Irish Sea (1991-2003) showed little difference in phytoplankton community structure. Loch Creran has experienced a large change in the “balance of organisms”, and hence a reduction in the PCI, between 1979-1981 and 2006/2007, associated with a decrease in chlorophyll but no apparent change in nutrients. These results are discussed in relation to the intended uses of the PCI as an index of biological quality for the Water Framework Directive (WFD) and an index of ecosystem health in the context of eutrophication. Although the method only measures change, it can also be used as an indicator of biological quality if the reference conditions are those defined for a WFD waterbody, and as an indicator of health if appropriately calibrated. Suggestions are made for further development.

Antiviral potential of cathelicidins.

Abstract: The global burden of morbidity and mortality arising from viral infections is high; however, the development of effective therapeutics has been slow. As our understanding of innate immunity has expanded over recent years, knowledge of natural host defenses against viral infections has started to offer potential for novel therapeutic strategies. An area of current research interest is in understanding the roles played by naturally occurring cationic host defense peptides, such as the cathelicidins, in these innate antiviral host defenses across different species. This research also has the potential to inform the design of novel synthetic antiviral peptide analogs and/or provide rationale for therapies aimed at boosting the natural production of these peptides. In this review, we will discuss our knowledge of the antiviral activities of cathelicidins, an important family of cationic host defense peptides, and consider the implications for novel antiviral therapeutic approaches.

Presence and digital tourism

Abstract: This paper provides an introduction to digital tourism as mediated by presence research as a means to create substantive user experiences (UX) for visitors. Tourism is a rich and varied socio-economic activity that permeates our global society. Digital tourism is the digital support of the tourist experience. In this paper we introduce and survey both fields and introduce a number of examples of tourist experiences based on our blended spaces approach. Cutting across this is the sense of presence that visitors can experience in real or digital tourist experiences. We conclude the paper with a discussion of designing the user experience in blended tourist spaces.