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Powering In-Body Nanosensors With Ultrasounds
Get PDFEmbedded nanosensors will be a key feature of emerging medical monitoring systems. Power for these sensors could be harvested from ultrasonic vibrations generated by portable miniature sources and converted to electrical energy by piezoelectric nanowires. This letter analyzes the frequency and intensity of ultrasounds required to power an embedded nanosensor subject to medical safety limits, absorption by human tissue and reflection from interfaces. We calculate input and output power at different levels of energy conversion efficiency. Our analysis suggests that ultrasounds can be a viable source for energy harvesting of in-body nanosensors
Assessing SME Service Innovation Capability Using a Maturity Matrix
Get PDFThe uncertain and challenging future facing Irish small and medium sized enterprises (SMEs) necessitates their ability to consistently and continuously adapt their services. There is growing evidence that this is determined by their service innovation capability, which describes the capacity to repeatedly develop and improve services. However, with little research activity and an absence of practical measurement or management tools, it is unlikely that its benefits can be realised. In response, this poster conceptualises firm-level service innovation capability as a second order, multi-dimensional construct composed of four interdependent process areas and tracks their development using a staged maturity matrix
Inclusion of Dipolar Interactions in the Mathematical Modelling of Magnetic Hyperthermia through the Landau-Lifshitz-Gilbert Equation
Get PDFMagnetic Hyperthermia Treatment (MHT) continues to occupy clinicians, and experimental & theo-
retical magneticians alike. The many modelling approaches for non-interacting magnetic nanoparti-
cles(MNPs) were outlined by Carrey et al. [1] at ICCSAMC 2014 in Dresden. Several authors have
outlined the important role interparticle interactions are likely to play in MHT for closely spaced
particles [1{6]. Modelling of MHT for non-interacting MNPs through the Landau-Lifshitz-Gilbert
(LLG) equation was undertaken by Ch^atel et al. [7].
Our aim is to incorporate the dipole-dipole interactions in the LLG analysis. The e�ects of interactions
on the frequency response of the heating mechanism are presented for two identical MNPs
Advances in Traffic Classification Techniques and in Network-aware Allocation of Datacenter Resources
Get PDFEmerging applications create tremendous volume of data traffic every day, increasingly
stressing the capabilities of the networks hosting these applications. Understanding the
communication patterns of these applications can significantly benefit the corresponding
network management tasks. Motivated by today’s wide use of data analysis techniques, this
thesis studies how to perform effective network management through using network data
analysis. We investigate problems in managing the QoS targets and resources in enterprize
networks and datacenter networks, presenting two applications of traffic analysis.
The first application of traffic analysis addresses the utilisation of traffic classification
techniques in enterprize networks to differentiate servicing flows of different classes or
applications. The traffic classification techniques developed based on statistical analysis
produce advantages over the existing techniques based on deep packet inspections or port
matching in the scenarios that new applications emerge and packets are encrypted. This
dissertation presents enhanced traffic classification techniques based on traffic analysis.
The second application addresses the requirement of effective resource allocation in
datacenters, where predictable performance is essential to the applications hosted in
datacenters. This thesis proposes resource allocation techniques that can allocate datacenter
resources in a way that the QoS requirements of Virtual Machines (VM) are met while
minimizing the amounts of required resources. This is achieved through the integrated use of
bin packing algorithms, effective bandwidth estimation techniques and software-defined
networking technologies, where network data are analyzed to identify the minimum amounts
of bandwidth required to meet the QoS targets for provisioning VMs on demand
An Investigation into the Bioaccumulation of Chromium by Macroalgae
Get PDFHeavy metals in industrial effluents are of particular concern because of their ability to bioaccumulate in the food chain, making it possible for toxic levels to reach higher animals and plants. Chromium is widely used in processes such as leather tanning, electroplating, pigmentation and in corrosion inhibitors. Trivalent and hexavalent are the most common species used in industry, with hexavalent being widely understood to be the most toxic. It is important, therefore, to understand the mechanisms of how chromium and other metals accumulate in the environment.
The aim of this project was to investigate metal, and in particular chromium uptake, by live seaweeds. This was done by characterising the seaweed (ICP-OES, Kjeldahl, FTIR), using the seaweed as a biomonitor, and looking at the surface morphology of the seaweed (AFM, SEM-EDX). A set of bioaccumulation experiments under many different conditions was carried out in order to determine the effect of seaweed species (Fucus vesiculosus, Palmaria palmata, Ulva lactuca), metal species (Cr(III) vs. Cr(VI)), season (May/June versus Feb/Mar), and temperature (7 ˚C vs. 16 ˚C) on metal uptake. To the author’s knowledge, this was the first study to look at bioaccumulation by live seaweed of these two chromium species.
Characterisation confirmed the presence of sulphate, carboxylate, amide, and phosphorus containing groups. Seasonal and inter-species differences in seaweed composition were also identified.
A biomonitoring study, carried out on F. vesiculosus and A. nodosum sampled in Ireland and Newfoundland, showed that both seaweeds are suitable biomonitors. Metal contents reflected the levels of pollution which were likely to be present in the sampling areas.
Surface microscopy showed that a biofilm was present on the surface of U. lactuca. A time course study on Cr(III) binding showed that the biofilm was disrupted and reduced as metal exposure continued. Further experiments using AFM, SEM-EDX and total viable surface counts did not show differences between blank and metal loaded seaweeds. This was likely to be because the experimental conditions were slightly different, with a lower final metal concentration. To the author’s knowledge, this was the first time the removal and disruption of a seaweed biofilm was shown by AFM, and the first time metal uptake in these three species was studied using AFM.
The following general trends were observed for Cr accumulation: U. lactuca>P. palmata>F. vesiculosus; Cr(III) > Cr(VI); 16 ˚C > 7 ˚C; Feb/Mar > May/Jun; intracellular uptake ~ 100%. Seasonal and inter-species differences were found to be attributable to difference in composition e.g. greater levels of P or N for a particular species, or a particular season. Greater binding at higher temperatures, could be because of greater cell membrane fluidity, increased metabolism and increased protein synthesis
Promoting Cancer and Screening Awareness in Women with Intellectual Disabilities: A Mixed Methods Study [Volume 1]
Get PDFPromoting Cancer and Screening Awareness in Women with Intellectual Disabilities: A Mixed Methods Study.
BY
Mary Reidy
Background: People with intellectual disabilities are living longer which has led to increasing cancer rates among this demographic. Women with intellectual disabilities are more likely to have poorer cancer awareness and lower screening participation than women in the general population. They also present at later stages of cancer despite similar cancer rates in both populations.
Aim: This two phase mixed methods study tested the feasibility and acceptability of a targeted educational intervention for women with ID and their carers. EMBRACES-ID (Early Monitoring of Breast and Cervical Cancer Signs & Screening in Intellectual Disabilities) aimed to raise the awareness of warning signs, risk factors, screening programmes, and promote early help-seeking on symptom discovery.
Methods: In line with the MRC’s Guidance for Complex Interventions this work was based on empirical evidence and was theoretically underpinned by Bandura’s Social Cognitive Theory. Phase I involved a survey of carers (n= 125) and women with mild to moderate ID (n = 45), as well as semi- structured interviews with 25 carers. Phase II involved the feasibility and acceptability testing of EMBRACES- ID among 25 women with mild to moderate ID and 9 carers. A pre-test/post-test design incorporating a 12 week evaluation survey and interview was utilised. Ethical approval for the study was received from the relevant Research Ethics Committees.
Findings: In Phase I, gaps in cancer and screening awareness were found. These results formed the basis for the development of the EMBRACES-ID intervention. In Phase II, testing of EMBRACES-ID identified changes in cancer and screening awareness for women with ID and their carers, the majority of changes were retained over the 12 week post intervention time frame.
Conclusions: EMBRACES-ID raised cancer and screening awareness for women with ID and their carers. This may lead to earlier diagnosis and treatment of cancers with better survival outcomes
Complex Information Systems Development and Deployment Processes: A GT Study of TCK [Appendices D-J]
No full textAccess Control System Specification and its Implications for Performance
Get PDFAccess control evaluation performance is a challenge in modern enterprises. Such enterprises are characterized by workflows involving extensive communication events, as information is shared within and between groups in that enterprise. Security administrators are tasked with enabling communication events that help the business achieve its objectives, and of preventing the rest. They develop policies and deploy them in ever more complex access control infrastructures, and it is not always clear how to ensure the deployments have adequate performance. In response, we propose a performance testbed (STACS), a means of generating policies and requests in bulk (DomainManager) for that testbed and a system for analyzing the performance measurements obtained from the testbed (PARPACS). STACS provides a means of performing reproducible, controlled experiments, so researchers can compare different performance improvement proposals on standard test infrastructure. DomainManager is built upon a flexible domain model that can be used as a foundation for a) generating large numbers of consistent, scenario-specific policies and requests and b) generating variants of those artifacts for performance comparison in STACS. PARPACS enables robust statistical models of performance to be built, so that researchers can predict performance and not just perform limited comparisons. Indeed, the three components are part of a larger ATLAS framework for diagnosing performance problems in an existing deployment and/or dimensioning a new deployment. Using these research contributions, we conducted extensive experiments to evaluate ATLAS and generated more research contributions in the form of findings. These findings relate to the effects on performance of domain size, policy authoring patterns, policy optimisations, request complexity, system resource (e.g., memory) availability etc. While many of the main effects might be expected, there are significant (and often surprising) interaction effects that need to be considered in any access control deployment. Although the motivating application concerned access control, ATLAS was designed so that it could be extended to other client-server performance studies, such as those concerning database query performance
Ca2+-signalling-based Molecular Communication Systems Towards Nanomedicine Development
Get PDFNanomedicine is an attempt to revolutionize current methods for diagnosing, treating and preventing diseases that integrates fields such as molecular biology, biotechnology as well as nanotechnology. One envisioned application is sensing and actuation capabilities at the molecular scale using nano scale devices, namely nanomachines. While numerous examples of these applications have been tested in vivo, the real deployments are far from reality. This is mainly due to limitations in controlling as well as monitoring their performance. At the same time, the miniature scale of nanomachines means their computational capabilities are also limited. However, integrating communication and networking functionalities can provide new opportunities for sensing and actuation applications of nanomachines. One form of communication that has been recently appointed to realise this vision is Molecular Communication. Many natural molecular communication systems are found inside the human body. The current challenge is to utilise these natural systems to create artificial biocompatible communication networks that can interconnect multiple nanomachines. Such nanonetworks can represent a new type of communication network that can also be connected to the Internet, enabling fine granular sensing deep inside the organs and tissues inside the human body. This new vision is defined as the Internet of Bio-Nano Things (IoBNT). The focus of this thesis is on developing artificial molecular communication systems for cellular tissues inside the human body. A model and analysis of a Ca2+-signalling-based molecular communication system for embedded nanomachines is proposed. A mathematical framework was developed for 3D tissues of different types of cells that communicate using Ca2+-signalling, where this framework integrates the gap junction behaviour as well as the physiological properties that can affect the communication behaviour. The framework analyses the end-to-end capacity, molecular delay, as well as molecular gain for the different types of tissues. Since cellular tissues are flexible body, the communication process is also modelled considering deformation and structural changes. The thesis also presents communication protocols from wireless communication networks applied to the Ca2+- signalling-based molecular communication system. This includes development of protocols, where channel impairments such as noise and poor information capacity were overcome using communication-by-silence theory in order to improve the end-to-end data rate for "On-Off Keying" modulation. The thesis also focuses on applications of the Ca2+-signalling-based molecular communication system. Firstly, a channel state detection/inference technique that provides information about the current cellular tissue conditions was designed, termed Molecular Nanonetwork Inference Process. The inference process utilizes a simple machine learning algorithm to learn and infer various metrics including the types of deformation, estimated locations of the nanomachines, as well as the concentration of Ca2+ ions used by the transmitters. The second application is based on modelling the tripartite synapse, and focuses particularly on astrocyte cells using Ca2+-signalling to communicate and provide upkeep to the neuronal networks. A feed-forward feedback control technique has been proposed to control synaptic quality in the tripartite synapses molecular communication channel, and this includes regulating the quantity of Ca2+ concentration within the cytosol in order to prevent any dangerous levels that can lead to diseases. At the same time, the feed-forward feedback control model is also used for molecular communication systems in order to prevent excessive noise within the channel, while maintaining decent data rate performance. Creating artificial communication systems that are embedded into the tissue, can lead to new forms of smart tissues that play a major role for future IoBNT vision
An Exploration of Evolving Learning Communities in the Micro Firm Rural Tourism Context: A Multi-Country Study
Get PDFRural stakeholder collaborations are considered pivotal to successful rural development. In this context a growing body of micro firm related tourism research acknowledges the value of collaborative learning networks and the learning relationships that develop within. However little research reveals how micro firms learn independently in the practice of tourism development in an ‘evolving learning community’ context. Drawing from Lave and Wenger’s (1991) community of practice perspective, this research seeks to explore the elements and relationships that influence learning in an evolving learning community (LC) in the micro firm rural tourism context. An evolving LC is defined as a group of businesses (micro firms) who collaborate with one another and other stakeholders in their community for the purpose of tourism development; in doing so they build shared meaning and learn in practice, as the community evolves from one stage to another. A comprehensive literature review reveals key criteria which influence evolving LC structures and interrelationships. These criteria are explored through two longitudinal interpretive case studies in tourism practitioner communities in Canada and Wales. Employed research techniques comprised interviews, observation, LC communication review and reflective diary maintenance. The findings offer insights into how the catalyst, structure and leadership, learning strategies, LC resources, communication, participation and identity and boundary criteria support or impede micro firm learner autonomy and influence the evolving LC’s learning dynamic. Recommendations are offered into optimised evolving LC support mechanisms at local, regional and national level; ultimately contributing to rural regional policy development in each domain