title: Antibacterial Ti-Mn-Cu alloys for biomedical applications

authors: Alqattan, Mohammad

subjects: titanium alloys

abstract: Titanium alloys are common biomedical materials due to their biocompatibility and mechanical performance. However, titanium alloys are expensive and, unless surface treated, generally cannot prevent surgical infections related to bacteria which can damage the integrity of the implant. In this study, new titanium alloys were developed via powder metallurgy and the addition of manganese and copper, respectively, aiming to limit the manufacturing costs and induce new functionality on the materials including antibacterial response. The addition of manganese and copper to titanium significantly changes the behaviour of the Ti-Mn-Cu alloys leading to the successful stabilization of the beta titanium phase, great refinement of the typical lamellar structure, and achievement of materials with low level of porosity. Consequently, it is found that the mechanical performance and the antibacterial efficacy are enhanced by the addition of a higher amount of alloying elements. The manufactured Ti-Mn-Cu alloys fulfil the requirements for structural biomedical implants and have antibacterial response making them potential candidates for permanent medical implants.

text: Antibacterial Ti-Mn-Cu alloys for biomedical applications Titanium alloys are common biomedical materials due to their biocompatibility and mechanical performance. However, titanium alloys are expensive and, unless surface treated, generally cannot prevent surgical infections related to bacteria which can damage the integrity of the implant. In this study, new titanium alloys were developed via powder metallurgy and the addition of manganese and copper, respectively, aiming to limit the manufacturing costs and induce new functionality on the materials including antibacterial response. The addition of manganese and copper to titanium significantly changes the behaviour of the Ti-Mn-Cu alloys leading to the successful stabilization of the beta titanium phase, great refinement of the typical lamellar structure, and achievement of materials with low level of porosity. Consequently, it is found that the mechanical performance and the antibacterial efficacy are enhanced by the addition of a higher amount of alloying elements. The manufactured Ti-Mn-Cu alloys fulfil the requirements for structural biomedical implants and have antibacterial response making them potential candidates for permanent medical implants.

year: 2020

title: Clustering for classification

authors: Evans, Reuben James Emmanuel

subjects: computer science

abstract: Advances in technology have provided industry with an array of devices for collecting data. The frequency and scale of data collection means that there are now many large datasets being generated. To find patterns in these datasets it would be useful to be able to apply modern methods of classification such as support vector machines. Unfortunately these methods are computationally expensive, quadratic in the number of data points in fact, so cannot be applied directly. This paper proposes a framework whereby a variety of clustering methods can be used to summarise datasets, that is, reduce them to a smaller but still representative dataset so that advanced methods can be applied. It compares the results of using this framework against using random selection on a large number of classification problems. Results show that clustering prior to classification is beneficial when employing a sophisticated classifier however when the classifier is simple the benefits over random selection are not justified given the added cost of clustering. The results also show that for each dataset it is important to choose a clustering method carefully.

text: Clustering for classification Advances in technology have provided industry with an array of devices for collecting data. The frequency and scale of data collection means that there are now many large datasets being generated. To find patterns in these datasets it would be useful to be able to apply modern methods of classification such as support vector machines. Unfortunately these methods are computationally expensive, quadratic in the number of data points in fact, so cannot be applied directly. This paper proposes a framework whereby a variety of clustering methods can be used to summarise datasets, that is, reduce them to a smaller but still representative dataset so that advanced methods can be applied. It compares the results of using this framework against using random selection on a large number of classification problems. Results show that clustering prior to classification is beneficial when employing a sophisticated classifier however when the classifier is simple the benefits over random selection are not justified given the added cost of clustering. The results also show that for each dataset it is important to choose a clustering method carefully.

year: 2011

title: Worlded object and its presentation: A Māori philosophy of language

authors: Mika, Carl Te Hira

abstract: In an era concerned with the survival of Indigenous languages, language as a general phenomenon needs to be thought of as thoroughly connected to one’s worldview. In this article, I propose a different conception of language that sides more with what I call ‘the worlding of things’ than linguistics. To foreshadow my speculations on language, I consider the possibility that, within the representation of one entity in perception, there exist all other entities. An entity is hence ‘worlded’—a key aspect of the term ‘whakapapa’. I then turn to think about language as a general phenomenon for Mäori, and its complex ability to world an entity even as it adumbrates that thing’s backdrop. I consider the verb ‘to be’ in that light, arguing that Mäori identify language as a sort of gathering of entities rather than an instrument for singling out one thing as thoroughly and separably evident. This article is therefore as much about the full participation of the world as it is about language; it also aims to counter the belief that language is merely a conveyor of ideas.

text: Worlded object and its presentation: A Māori philosophy of language In an era concerned with the survival of Indigenous languages, language as a general phenomenon needs to be thought of as thoroughly connected to one’s worldview. In this article, I propose a different conception of language that sides more with what I call ‘the worlding of things’ than linguistics. To foreshadow my speculations on language, I consider the possibility that, within the representation of one entity in perception, there exist all other entities. An entity is hence ‘worlded’—a key aspect of the term ‘whakapapa’. I then turn to think about language as a general phenomenon for Mäori, and its complex ability to world an entity even as it adumbrates that thing’s backdrop. I consider the verb ‘to be’ in that light, arguing that Mäori identify language as a sort of gathering of entities rather than an instrument for singling out one thing as thoroughly and separably evident. This article is therefore as much about the full participation of the world as it is about language; it also aims to counter the belief that language is merely a conveyor of ideas.

year: 2016