title: Characterization of the bacterioplankton communities in the melt-water ponds of Bratina Island, Victoria Land, Antarctica

authors: Archer, Stephen David James

subjects: melt-water

abstract: Antarctic ecosystems (such as the ponds by Bratina Island, Antarctica) provide an excellent opportunity to examine organisms that can live in one of the most extreme and geochemically varied environments in the world. These ponds are of interest as each one can vary greatly in size, depth, and age as well as profiles of dissolved oxygen, metal concentrations, pH and salinity. Even within ponds geochemically distinct stratified layers can form which can greatly influence their microbial communities. There are a number of studies which indicate that microbial populations found in Antarctic ponds will be highly diverse and variable due to the uniqueness of the environment. This study aims to increase our knowledge of microbial biodiversity and the environmental factors which structure them, in particular the stratification transition zones within ponds water columns. A thorough set of biological samples were taken from five selected ponds during mid-summer in the 09-10 season to complement those taken during the winter freeze-up in the 07-08 extended season by Hawes and co-workers. Oxygen concentration, pH, conductivity and temperature of each pond water sample were measured in the field and water samples were taken back to the University of Waikato for further analysis. This research primarily used the DNA fingerprinting technique ARISA, matched with geochemistry to identify and characterise the resident and functional members of the microbial community and understand how the community is structured in relation to environmental conditions. We found that the planktonic populations of the Bratina Island ponds do vary between ponds, that each pond has its own chemical signature and that populations do change with depth. One of the studied ponds, Egg, was found to have an extreme chemical stratification leading to significantly different populations at each depth. Data analysis using BEST analysis determined that the changes in the bacterial populations in Egg are primarily in relation to the pH and conductivity at each depth which changes dramatically in the lower depths.

text: Characterization of the bacterioplankton communities in the melt-water ponds of Bratina Island, Victoria Land, Antarctica Antarctic ecosystems (such as the ponds by Bratina Island, Antarctica) provide an excellent opportunity to examine organisms that can live in one of the most extreme and geochemically varied environments in the world. These ponds are of interest as each one can vary greatly in size, depth, and age as well as profiles of dissolved oxygen, metal concentrations, pH and salinity. Even within ponds geochemically distinct stratified layers can form which can greatly influence their microbial communities. There are a number of studies which indicate that microbial populations found in Antarctic ponds will be highly diverse and variable due to the uniqueness of the environment. This study aims to increase our knowledge of microbial biodiversity and the environmental factors which structure them, in particular the stratification transition zones within ponds water columns. A thorough set of biological samples were taken from five selected ponds during mid-summer in the 09-10 season to complement those taken during the winter freeze-up in the 07-08 extended season by Hawes and co-workers. Oxygen concentration, pH, conductivity and temperature of each pond water sample were measured in the field and water samples were taken back to the University of Waikato for further analysis. This research primarily used the DNA fingerprinting technique ARISA, matched with geochemistry to identify and characterise the resident and functional members of the microbial community and understand how the community is structured in relation to environmental conditions. We found that the planktonic populations of the Bratina Island ponds do vary between ponds, that each pond has its own chemical signature and that populations do change with depth. One of the studied ponds, Egg, was found to have an extreme chemical stratification leading to significantly different populations at each depth. Data analysis using BEST analysis determined that the changes in the bacterial populations in Egg are primarily in relation to the pH and conductivity at each depth which changes dramatically in the lower depths.

year: 2011

title: Visual–tactile perception of biobased composites

authors: Thundathil, Manu

subjects: material perception

abstract: Biobased composites offer unique properties in the context of sustainable material production as well as end-of-life disposal, which places them as viable alternatives to fossil-fuel-based materials. However, the large-scale application of these materials in product design is hindered by their perceptual handicaps and understanding the mechanism of biobased composite perception, and its constituents could pave the way to creating commercially successful biobased composites. This study examines the role of bimodal (visual and tactile) sensory evaluation in the formation of biobased composite perception through the Semantic Differential method. It is observed that the biobased composites could be grouped into different clusters based on the dominance and interplay of various senses in perception forming. Attributes such as Natural, Beautiful, and Valuable are seen to correlate with each other positively and are influenced by both visual and tactile characteristics of the biobased composites. Attributes such as Complex, Interesting, and Unusual are also positively correlated but dominated by visual stimuli. The perceptual relationships and components of beauty, naturality, and value and their constituent attributes are identified, along with the visual and tactile characteristics that influence these assessments. Material design leveraging these biobased composite characteristics could lead to the creation of sustainable materials that would be more attractive to designers and consumers.

text: Visual–tactile perception of biobased composites Biobased composites offer unique properties in the context of sustainable material production as well as end-of-life disposal, which places them as viable alternatives to fossil-fuel-based materials. However, the large-scale application of these materials in product design is hindered by their perceptual handicaps and understanding the mechanism of biobased composite perception, and its constituents could pave the way to creating commercially successful biobased composites. This study examines the role of bimodal (visual and tactile) sensory evaluation in the formation of biobased composite perception through the Semantic Differential method. It is observed that the biobased composites could be grouped into different clusters based on the dominance and interplay of various senses in perception forming. Attributes such as Natural, Beautiful, and Valuable are seen to correlate with each other positively and are influenced by both visual and tactile characteristics of the biobased composites. Attributes such as Complex, Interesting, and Unusual are also positively correlated but dominated by visual stimuli. The perceptual relationships and components of beauty, naturality, and value and their constituent attributes are identified, along with the visual and tactile characteristics that influence these assessments. Material design leveraging these biobased composite characteristics could lead to the creation of sustainable materials that would be more attractive to designers and consumers.

year: 2023-02-23

title: Perception and flagging of loanwords – A diachronic case-study of Māori loanwords in New Zealand English

authors: Levendis, Katharine

abstract: This paper combines a quantitative and qualitative analysis of a diachronic corpus of New Zealand newspapers built to analyse the use of Māori loanwords in New Zealand English. We report findings in relation to flagging (marking of loanwords as being foreign material in a given language) and show that it is (weakly) predicated by frequency-of-use and by semantic category of the loanword (core loans are flagged more than cultural ones), but not by listedness. Alongside this trend, we note that perceptions of writers using the words vary enormously in regard to which loans are integrated and familiar, matching neither listedness nor frequency-of-use patterns. This indicates that in NZE, loanword use remains strongly tied up with socio-political identity and language ideology, rather than rooted in linguistic factors (such as, bilingualism or filling in lexical gaps).

text: Perception and flagging of loanwords – A diachronic case-study of Māori loanwords in New Zealand English This paper combines a quantitative and qualitative analysis of a diachronic corpus of New Zealand newspapers built to analyse the use of Māori loanwords in New Zealand English. We report findings in relation to flagging (marking of loanwords as being foreign material in a given language) and show that it is (weakly) predicated by frequency-of-use and by semantic category of the loanword (core loans are flagged more than cultural ones), but not by listedness. Alongside this trend, we note that perceptions of writers using the words vary enormously in regard to which loans are integrated and familiar, matching neither listedness nor frequency-of-use patterns. This indicates that in NZE, loanword use remains strongly tied up with socio-political identity and language ideology, rather than rooted in linguistic factors (such as, bilingualism or filling in lexical gaps).

year: 2019