The limitations of speech control: perceptions of provision of speech-driven environmental controls

This study set out to collect data from assistive technology professionals about their provision of speech-driven environmental control systems. This study is part of a larger study looking at developing a new speech-driven environmental control system

Extinction in the Anthropocene: A Critical Analysis

Anthropogenic species extinction is considered one of the planet's most pressing environmental issues, receiving widespread attention across academic and public realms. Accelerating species loss, including the idea that humans are causing the sixth mass extinction, is deemed emblematic of human impacts upon the natural world and a key signature of the Anthropocene epoch. Although thousands of articles and books exist about extinction, it is rare to encounter a deep, reflexive account of what it is, what it is not, what it means to go extinct, and the ontological, societal, and existential implications of the current episode for humans. To flesh out these lesser explored aspects, this thesis places various facets of extinction in dialogue with each other, including scientific, anthropological, philosophical, and historical elements. I examine the scientific claim that humans have initiated another mass extinction event; the cultural history of its emergence, and how it has become a crystallising concept bringing together broader fears about the state of the planet; anthropological aspects, including the extent to which anxieties about the environmental crisis manifest as ontological concerns about the end of the world; and I explore the potential for re-imagining the extinction crisis in a way that does not simply reduce the future to loss. My primary aim is to foster a more effective cross-fertilisation and exchange of ideas between the social and natural sciences, developing better thinking, questions, and approaches toward this vexing issue. The research is undertaken via a comprehensive literature review across numerous disciplines. My findings confirm that the sixth extinction is a speculative label unsupported by empirical science and also an inappropriate model to discuss anthropogenic species loss because of the macro-evolutionary benefits of prior mass extinctions. I also reveal that ideas about extinction have dramatically transformed over the past two centuries, driven by science but influenced by broader cultural issues. I determine that the sixth extinction and the Anthropocene constitute a crisis of modernity, the threat to which is equated with the end of the world and the biological disappearance of humans. And irrespective of whether humans are causing the sixth extinction, we are perhaps setting the stage for the 'sixth genesis' of diversity millions of years hence, when our activities could lead to unprecedented species richness. In conclusion, I argue that extinction is a profoundly temporal and ethical phenomenon. Depending upon the prism one views the current extinction episode, it can be seen and interpreted differently. A near-time perspective confirms we are causing a 'biological annihilation' of many lifeforms, but the long-term view is that the planet is experiencing just another crisis in the history of life, and whatever humans do in the short-term will be subsumed into the deeper patterns of natural history. This suggests that concerning ourselves with the well-being of other species, beyond their value as material and cultural resources, is an issue of intraspecies ethics, involving humans 'holding open space' in the world for our non-human companions so they may diversify and resonate into the future

A comparison of hardness and abrasion resistance of two sealant materials after polymerization from different distances by different light sources

Indiana University-Purdue University Indianapolis (IUPUI)BACKGROUND The efficacy of sealants to aid in the prevention of pit and fissure caries is well documented. In order for the sealants to be effective, they must be placed properly and retained for as long as possible. Clinicians must be aware that the proper placement of sealants is technique-sensitive and must be well controlled in order to achieve the best results. This study aims to determine if certain variables have an effect on curing of the sealant material to a degree that would compromise its integrity, strength, and longevity. METHODS AND MATERIALS Two commonly used sealant materials Ultraseal XT (Ultradent Products Inc., South Jordan, UT) and Delton (Dentsply International, Woodbridge, Ontario, Canada) were chosen and tested for microhardness and abrasion resistance after they were polymerized. This study did not focus on the materials themselves, but rather the technique by which they were polymerized and what effect this had on the materials. Three separate light sources, a traditional halogen light (QHL 75, Dentsply International, Woodbridge, Ontario, Canada), and two newer LED lights (Ultralume LED, Ultradent Products Inc., South Jordan, UT; and 3M Freelight LED, 3M Corp, St Paul, MN) were used in this study. The materials were then cured with each light at each of three different distances: contact (0.5 mm), 2 mm, and 10 mm. The effects of light source variation and distance from the material at the time of polymerization was then evaluated for any significance to sealant placement technique. Specimens were tested for each variable combination of sealant material, light source, and distance between the two while curing. Six samples were tested for each variable grouping for abrasion resistance, and four separate san1ples were tested fron1 the san1e grouping for Knoop hardness. The results were analyzed for significance to determine if certain techniques are or could be beneficial or damaging to the quality of care provided by today's practitioners. RESULTS It was found that materials and light sources varied in combination and with different techniques (e.g., distance). In general, the top surface polymerized best when cured at a distance of 2 mm to 10 mm, while the bottom surface polymerized best at a distance of 0.5 mm. The halogen light consistently outperformed the two LED lights, with the 3M LED consistently producing the worst results. CONCLUSIONS The halogen curing light used in this study outperformed the LED lights in almost every category, despite the LED light manufacturer's claims of equality. For more reliable polymerization, the halogen light should be used. SIGNIFICANCE The practitioner must be aware of the material that he/she is using and how the chosen light source polymerizes that material. Manufacturers' claims and recommendations cannot be trusted to accurately produce the best results with every product on the market today, sometimes not even with the manufacturers' own products. It is crucial for practitioners to be well versed and knowledgeable about the products that they use, based on current research and not manufacturers' claims