title: Development of Cu-bearing powder metallurgy Ti alloys for biomedical applications

authors: Bolzoni, Leandro

abstract: Cu-bearing Ti alloys could be used as structural biomedical materials where the releasing of Cu ions is beneficial to lower infection incidences associated with surgical implants. The manufacturing of these alloys via powder metallurgy techniques can lower the production costs. In this study three ternary Cu-bearing Ti-xAl-yCu alloys were produced using conventional powder metallurgy. The mechanical properties increase with the amount of alloying elements. Samples of each composition were also forged to clarify the effect of subjecting them to hot deformation. Forging the samples improved the strength of the alloys due to the reduction of porosity and the refinement of the microstructural features. It is found that Ti–2Al–1Cu is the most ductile, Ti–6Al–4Cu is the strongest and Ti–10Al–5Cu has a purely elastic behaviour. Some of these powder metallurgy Ti-xAl-yCu alloys have better overall mechanical behaviour than their cast counterparts and therefore are valuable alternative to produce medical and dental implants with improved properties and reduced cost.

text: Development of Cu-bearing powder metallurgy Ti alloys for biomedical applications Cu-bearing Ti alloys could be used as structural biomedical materials where the releasing of Cu ions is beneficial to lower infection incidences associated with surgical implants. The manufacturing of these alloys via powder metallurgy techniques can lower the production costs. In this study three ternary Cu-bearing Ti-xAl-yCu alloys were produced using conventional powder metallurgy. The mechanical properties increase with the amount of alloying elements. Samples of each composition were also forged to clarify the effect of subjecting them to hot deformation. Forging the samples improved the strength of the alloys due to the reduction of porosity and the refinement of the microstructural features. It is found that Ti–2Al–1Cu is the most ductile, Ti–6Al–4Cu is the strongest and Ti–10Al–5Cu has a purely elastic behaviour. Some of these powder metallurgy Ti-xAl-yCu alloys have better overall mechanical behaviour than their cast counterparts and therefore are valuable alternative to produce medical and dental implants with improved properties and reduced cost.

year: 2019

title: Extracting game-play metric data from audio/video processing: A practical solution for game studies research

authors: Marczak, Raphaël

subjects: videogame classification

abstract: Today videogame classification works to a set of guidelines initially designed for, and more conducive to linear mediums (film, television and literature). As a result, digital games receive an age restriction rating based on both their depiction of harmful content and its prospective impact on players. Not accounting for the medium’s interactive qualities means that envisaging the player’s experience and the nature and impact of interactions between players and game texts remains a largely inferential practice and an exercise in caution. Given the medium’s interactive nature, we argue that classification processes would be supported by research that provides empirical accounts of the interactive experience of games. In order to take into account the unique experiential properties of games, a mixed methodological approach located at an intersection between humanities, social sciences and computer science is being employed in a large-scale study of player experiences. This paper presents one of the earliest challenges for this study: the capacity to gather game-play metric data from game texts that are selected by participants as an ongoing process throughout the course of the study. With no real advance knowledge of game choices, access to source code or game developers, a pragmatic solution was required to capture player interactions with game texts. This paper presents the beginnings of a method of gathering game-play metrics through utilizing audio and video processing and its required synchronization with other forms of data output.

text: Extracting game-play metric data from audio/video processing: A practical solution for game studies research Today videogame classification works to a set of guidelines initially designed for, and more conducive to linear mediums (film, television and literature). As a result, digital games receive an age restriction rating based on both their depiction of harmful content and its prospective impact on players. Not accounting for the medium’s interactive qualities means that envisaging the player’s experience and the nature and impact of interactions between players and game texts remains a largely inferential practice and an exercise in caution. Given the medium’s interactive nature, we argue that classification processes would be supported by research that provides empirical accounts of the interactive experience of games. In order to take into account the unique experiential properties of games, a mixed methodological approach located at an intersection between humanities, social sciences and computer science is being employed in a large-scale study of player experiences. This paper presents one of the earliest challenges for this study: the capacity to gather game-play metric data from game texts that are selected by participants as an ongoing process throughout the course of the study. With no real advance knowledge of game choices, access to source code or game developers, a pragmatic solution was required to capture player interactions with game texts. This paper presents the beginnings of a method of gathering game-play metrics through utilizing audio and video processing and its required synchronization with other forms of data output.

year: 2012-07-21

title: A core phyllosphere microbiome exists across distant populations of a tree species indigenous to New Zealand

authors: Noble, Anya S.

subjects: Science & Technology

abstract: The phyllosphere microbiome is increasingly recognised as an influential component of plant physiology, yet it remains unclear whether stable host-microbe associations generally exist in the phyllosphere. Leptospermum scoparium (mānuka) is a tea tree indigenous to New Zealand, and honey derived from mānuka is widely known to possess unique antimicrobial properties. However, the host physiological traits associated with these antimicrobial properties vary widely, and the specific cause of such variation has eluded scientists despite decades of research. Notably, the mānuka phyllosphere microbiome remains uncharacterised, and its potential role in mediating host physiology has not been considered. Working within the prevailing core microbiome conceptual framework, we hypothesise that the phyllosphere microbiome of mānuka exhibits specific host association patterns congruent with those of a microbial community under host selective pressure (null hypothesis: the mānuka phyllosphere microbiome is recruited stochastically from the surrounding environment). To examine our hypothesis, we characterised the phyllosphere and associated soil microbiomes of five distinct and geographically distant mānuka populations across the North Island of New Zealand. We identified a habitat-specific and relatively abundant core microbiome in the mānuka phyllosphere, which was persistent across all samples. In contrast, non-core phyllosphere microorganisms exhibited significant variation across individual host trees and populations that was strongly driven by environmental and spatial factors. Our results demonstrate the existence of a dominant and ubiquitous core microbiome in the phyllosphere of mānuka, supporting our hypothesis that phyllosphere microorganisms of mānuka exhibit specific host association and potentially mediate physiological traits of this nationally and culturally treasured indigenous plant. In addition, our results illustrate biogeographical patterns in mānuka phyllosphere microbiomes and offer insight into factors contributing to phyllosphere microbiome assembly.

text: A core phyllosphere microbiome exists across distant populations of a tree species indigenous to New Zealand The phyllosphere microbiome is increasingly recognised as an influential component of plant physiology, yet it remains unclear whether stable host-microbe associations generally exist in the phyllosphere. Leptospermum scoparium (mānuka) is a tea tree indigenous to New Zealand, and honey derived from mānuka is widely known to possess unique antimicrobial properties. However, the host physiological traits associated with these antimicrobial properties vary widely, and the specific cause of such variation has eluded scientists despite decades of research. Notably, the mānuka phyllosphere microbiome remains uncharacterised, and its potential role in mediating host physiology has not been considered. Working within the prevailing core microbiome conceptual framework, we hypothesise that the phyllosphere microbiome of mānuka exhibits specific host association patterns congruent with those of a microbial community under host selective pressure (null hypothesis: the mānuka phyllosphere microbiome is recruited stochastically from the surrounding environment). To examine our hypothesis, we characterised the phyllosphere and associated soil microbiomes of five distinct and geographically distant mānuka populations across the North Island of New Zealand. We identified a habitat-specific and relatively abundant core microbiome in the mānuka phyllosphere, which was persistent across all samples. In contrast, non-core phyllosphere microorganisms exhibited significant variation across individual host trees and populations that was strongly driven by environmental and spatial factors. Our results demonstrate the existence of a dominant and ubiquitous core microbiome in the phyllosphere of mānuka, supporting our hypothesis that phyllosphere microorganisms of mānuka exhibit specific host association and potentially mediate physiological traits of this nationally and culturally treasured indigenous plant. In addition, our results illustrate biogeographical patterns in mānuka phyllosphere microbiomes and offer insight into factors contributing to phyllosphere microbiome assembly.

year: 2020