A qualititative approach to HCI research

Whilst science has a strong reliance on quantitative and experimental methods, there are many complex, socially based phenomena in HCI that cannot be easily quantified or experimentally manipulated or, for that matter, ethically researched with experiments. For example, the role of privacy in HCI is not obviously reduced to numbers and it would not be appropriate to limit a person's privacy in the name of research. In addition, technology is rapidly changing – just think of developments in mobile devices, tangible interfaces and so on – making it harder to abstract technology from the context of use if we are to study it effectively. Developments such as mediated social networking and the dispersal of technologies in ubiquitous computing also loosen the connection between technologies and work tasks that were the traditional cornerstone of HCI. Instead, complex interactions between technologies and ways of life are coming to the fore. Consequently, we frequently find that we do not know what the real HCI issues are before we start our research. This makes it hard, if not actually impossible, to define the variables necessary to do quantitative research, (see Chapter 2). Within HCI, there is also the recognition that the focus on tasks is not enough to design and implement an effective system. There is also a growing need to understand how usability issues are subjectively and collectively experienced and perceived by different user groups (Pace, 2004; Razavim and Iverson, 2006). This means identifying the users' emotional and social drives and perspectives; their motivations, expectations, trust, identity, social norms and so on. It also means relating these concepts to work practices, communities and organisational social structures as well as organisational, economic and political drivers. These issues are increasingly needed in the design, development and implementation of systems to be understood both in isolation and as a part of the whole. HCI researchers are therefore turning to more qualitative methods in order to deliver the research results that HCI needs.With qualitative research, the emphasis is not on measuring and producing numbers but instead on understanding the qualities of a particular technology and how people use it in their lives, how they think about it and how they feel about it. There are many varied approaches to qualitative research within the social sciences depending on what is being studied, how it can be studied and what the goals of the research are.Within HCI, though, grounded theory has been found to provide good insights that address well the issues raised above (Pace, 2004; Adams, Blandford and Lunt, 2005; Razavim and Iverson, 2006). The purpose of this chapter is to give an overview of how grounded theory works as a method. Quantitative research methods adopt measuring instruments and experimental manipulations that can be repeated by any researcher (at least in principle) and every effort is made to reduce the influence of the researcher on the researched, which is regarded as a source of bias or error. In contrast, in qualitative research, where the goal is understanding rather than measuring and manipulating, the subjectivity of the researcher is an essential part of the production of an interpretation. The chapter therefore discusses how the influence of the researcher can be ameliorated through the grounded theory methodology whilst also acknowledging the subjective input of the researcher through reflexivity. The chapter also presents a case study of how grounded theory was used in practice to study people's use and understanding of computer passwords and related security

Targeting chromatin aging - the epigenetic impact of longevity-associated interventions

A rapidly growing body of evidence has shown that chromatin undergoes radical alterations as an organism ages, but how these changes relate to aging itself is an open question. It is likely that these processes contribute to genomic instability and loss of transcriptional fidelity, which in turn drives deleterious age-related phenotypes. Interventions associated with increased healthspan and longevity such as reduced insulin/IGF signalling (IIS), inhibition of mTOR and energy depletion resulting in SIRT1/AMPK activation, all have beneficial effects which ameliorate multiple facets of age-associated decline. The impact of these interventions on the epigenome is less certain. In this review we highlight the potential of these interventions to act directly upon the epigenome and promote a youthful chromatin landscape, maintaining genetic and transcriptional memory throughout the lifecourse. We propose that this is a fundamental mechanism through which these interventions are able to curtail the incidence of age-related disease. By revisiting these well characterised interventions, we may be able to identify targetable effectors of chromatin function and use this knowledge to enhance healthspan and longevity in human populations through the measured application of dietary and small molecule interventions

Extracting More Data from LiDAR in Forested Areas by Analyzing Waveform Shape

Light Detection And Ranging (LiDAR) in forested areas is used for constructing Digital Terrain Models (DTMs), estimating biomass carbon and timber volume and estimating foliage distribution as an indicator of tree growth and health. All of these purposes are hindered by the inability to distinguish the source of returns as foliage, stems, understorey and the ground except by their relative positions. The ability to separate these returns would improve all analyses significantly. Furthermore, waveform metrics providing information on foliage density could improve forest health and growth estimates. In this study, the potential to use waveform LiDAR was investigated. Aerial waveform LiDAR data were acquired for a New Zealand radiata pine plantation forest, and Leaf Area Density (LAD) was measured in the field. Waveform peaks with a good signal-to-noise ratio were analyzed and each described with a Gaussian peak height, half-height width, and an exponential decay constant. All parameters varied substantially across all surface types, ruling out the potential to determine source characteristics for individual returns, particularly those with a lower signal-to-noise ratio. However, pulses on the ground on average had a greater intensity, decay constant and a narrower peak than returns from coniferous foliage. When spatially averaged, canopy foliage density (measured as LAD) varied significantly, and was found to be most highly correlated with the volume-average exponential decay rate. A simple model based on the Beer-Lambert law is proposed to explain this relationship, and proposes waveform decay rates as a new metric that is less affected by shadowing than intensity-based metrics. This correlation began to fail when peaks with poorer curve fits were included

Another dimension from LiDAR – Obtaining foliage density from full waveform data

LiDAR tells the user where surfaces are, not what they are. In this study we investigate the potential for waveform LiDAR to provide more information on the nature of the returns over forestry. Waveform LiDAR was acquired for ten Pinus radiata plots in a New Zealand plantation, along with comprehensive leaf area sampling in 2m vertical bands. The decay rate of each waveform peak was shown to be a useful tool for estimating foliage density, and has potential for identifying regions containing ground and understorey. Leaf Area Density (LAD) is an expression of foliage density per unit height, and a relationship between waveform decay rate and LAD was developed with an R2 of 56%. Incorporating the proportion of discrete LiDAR that fell in that band (which itself has an R2 of 50%) improves this model to explain 69% of the variation in LAD. This is a good result, especially given the costs and difficulties in measuring leaf area directly. As foliage density varies dramatically on a fine scale it was not possible to differentiate the nature of every single LiDAR return – but by averaging over a small area local variation in LAD could be easily mapped. Ground returns could be distinguished as having short decays, and broad leafed understorey typically had values between those of the canopy and ground, although surface roughness and slope make it impossible to robustly identify single returns. This study produced a useful model for estimating LAD in Pinus radiata which could easily be extended to other coniferous species

Simple Closed Geodesics in Hyperbolic 3-Manifolds

This paper determines which orientable hyperbolic 3-manifolds contain simple closed geodesics. The Fuchsian group corresponding to the thrice-punctured sphere generates the only example of a complete non-elementary orientable hyperbolic 3-manifold that does not contain a simple closed geodesic. We do not assume that the manifold is geometrically finite or that it has finitely generated fundamental group.Comment: 7 pages, to appear in the Bulletin of the London Mathematical Societ

Predictions for the fracture toughness of cancellous bone of fracture neck of femur patients

Current protocol in determining if a patient is osteoporotic and their fracture risk is based on dual energy X-ray absorptiometry (DXA). DXA gives an indication of their bone mineral density (BMD) which is the product of both the porosity and density of the mineralized bone tissue; this is usually taken at the hip. The DXA results are assessed using the fracture risk assessment tool as recommended by the World Health Organization. While this provides valuable data on a person’s fracture risk advancements in medical imagining technology enables development of more robust and accurate risk assessment tools. In order to develop such tools in vitro analysis of bone is required to assess the morphological properties of bone osteoporotic bone tissue and how these pertain to the fracture toughness (Kcmax) of the tissue.Support was provided by the EPSRC (EP/K020196: Point-ofCare High Accuracy Fracture Risk Prediction), the UK Department of Transport under the BOSCOS (Bone Scanning for Occupant Safety) project, and approved by Gloucester and Cheltenham NHS Trust hospitals under ethical consent (BOSCOS – Mr. Curwen CI REC ref 01/179G)

Aging-induced stem cell mutations as drivers for disease and cancer

Aging is characterized by a decrease in genome integrity, impaired organ maintenance, and an increased risk of cancer, which coincide with clonal dominance of expanded mutant stem and progenitor cell populations in aging tissues, such as the intestinal epithelium, the hematopoietic system, and the male germline. Here we discuss possible explanations for age-associated increases in the initiation and/or progression of mutant stem/progenitor clones and highlight the roles of stem cell quiescence, replication-associated DNA damage, telomere shortening, epigenetic alterations, and metabolic challenges as determinants of stem cell mutations and clonal dominance in aging

Engineering Polymer Informatics

The poster describes a strategy of for the development of polymer informatics. In particular, the development of polymer markup language, a polymer ontology and natural language processing tools for polymer literature

CONDITIONS FOR SUCCESSFUL STRATEGIC ALLIANCES IN THE FOOD INDUSTRY

This paper focuses on strategic fuzzy alliances (SFAs) and the role of trust in business-to-business relationships. First, a theoretical model of governance choice involving strategic alliances is developed, integrating the Shapiro, Sheppard, and Cheraskin (1992) taxonomy of trust into a neoinstitutional framework. Second, this model, based on transaction theory, is then used to generate necessary and sufficient conditions for trust-based agreements. The third component of this paper is an empirical model, which tests the above theory. Finally, managerial implications from the results are discussed.Institutional and Behavioral Economics,