title: Marine tephrochronology: A personal perspective

authors: Lowe, David J.

abstract: This special volume on marine tephrochronology is remarkable, and timely, because it marks a concerted step towards what might be informally termed ‘phase 3’ of a revolution in Quaternary geosciences that began around 40 years ago. The 10 articles collectively represent a re-focussed examination of tephras and cryptotephras preserved in ocean sediments at various locations and the authors describe their significance for a range of subdisciplines. Eight articles provide a new understanding of the origin, distribution and ages of various tephra and cryptotephra deposits and their stratigraphic inter-relationships; how the terrestrial ages of the tephra/crypotephra deposits relate to those of enclosing sediments and inform the ongoing development of the marine radiocarbon time-scale; mechanisms for the emplacement, remobilization or bioturbation of the tephras or cryptotephras; and volcanic eruption history. Two further articles document the characterization of tephra-derived glass shards using microbeam techniques to analyse 30–40 elements from individual shards as small as 10 µm in diameter. The collection thus provides snapshots of many aspects of the latest developments and directions in tephra studies – volcanology, primary and secondary dispersal, stratigraphy, single-grain characterization, chronology – through the medium of marine sediments. My personal perspective reflects briefly on how this point was reached and identifies a few of the important milestones on the way from ‘phase 1’ to ‘phase 3’. I am privileged to write it. Marine science revolution As an undergraduate in the early-mid 1970s, I recall my first real ‘awakening’ regarding the dynamic nature of science, and of Quaternary geoscience in particular, when told about deep-sea core V28-238 from the equatorial Pacific Ocean (Shackleton & Opdyke 1973; >2650 citations, Google Scholar). Analogous to the opening notes of Beethoven's 5th Symphony, perhaps the most famous quartet of notes in history, the alpha-numerical assemblage ‘V28-2

text: Marine tephrochronology: A personal perspective This special volume on marine tephrochronology is remarkable, and timely, because it marks a concerted step towards what might be informally termed ‘phase 3’ of a revolution in Quaternary geosciences that began around 40 years ago. The 10 articles collectively represent a re-focussed examination of tephras and cryptotephras preserved in ocean sediments at various locations and the authors describe their significance for a range of subdisciplines. Eight articles provide a new understanding of the origin, distribution and ages of various tephra and cryptotephra deposits and their stratigraphic inter-relationships; how the terrestrial ages of the tephra/crypotephra deposits relate to those of enclosing sediments and inform the ongoing development of the marine radiocarbon time-scale; mechanisms for the emplacement, remobilization or bioturbation of the tephras or cryptotephras; and volcanic eruption history. Two further articles document the characterization of tephra-derived glass shards using microbeam techniques to analyse 30–40 elements from individual shards as small as 10 µm in diameter. The collection thus provides snapshots of many aspects of the latest developments and directions in tephra studies – volcanology, primary and secondary dispersal, stratigraphy, single-grain characterization, chronology – through the medium of marine sediments. My personal perspective reflects briefly on how this point was reached and identifies a few of the important milestones on the way from ‘phase 1’ to ‘phase 3’. I am privileged to write it. Marine science revolution As an undergraduate in the early-mid 1970s, I recall my first real ‘awakening’ regarding the dynamic nature of science, and of Quaternary geoscience in particular, when told about deep-sea core V28-238 from the equatorial Pacific Ocean (Shackleton & Opdyke 1973; >2650 citations, Google Scholar). Analogous to the opening notes of Beethoven's 5th Symphony, perhaps the most famous quartet of notes in history, the alpha-numerical assemblage ‘V28-2

year: 2014

title: Identifying causes of high pH in lamb meat

authors: Hontiveros, Garrianne Fatima

subjects: meat

abstract: Lamb meat export is a multi-billion-dollar New Zealand industry. Therefore, strategies to maintain and improve quality have immediate commercial benefit. Consumers judge quality by colour, tenderness, and flavour, all of which are affected by ultimate pH (pHu). Ideal meat pHu is 5.5 and is influenced by muscle glycogen concentration. Insufficient muscle glycogen at slaughter results in high pHu (>5.8) which results in tough meat, dark colour, and shorter storage life. The decrease in meat pH post-slaughter is caused by the build-up of H+ ions as a consequence of anaerobic glycolysis of glycogen for ATP formation. Physical stress depletes muscle glycogen, prompting consumers to conclude animal mistreatment. However, stress, does not necessarily equate to abuse as all animals experience some level of pre-slaughter stress and any negative effects depend on duration, type, intensity, and susceptibility. Studies have focused on post-farm-gate stressors (e.g. transport and lairage) but less clear is the role of on-farm stressors on the incidence of high pHu. The aim of this study was to investigate the variation of muscle glycogen of lambs on-farm, examine the use of heat shock protein 20 (HSP20) as a marker for physiological stress, and determine any relationship between residual glycogen level and meat quality attributes such as water binding capacity (WBC), drip loss, microbial abundance, fat, protein, and water content.  

Two observations were conducted. Firstly, 60 animals from 2 farms with different production systems: wethers (castrated males) were raised with ewes in Farm 1, whereas, intact rams, wethers, cryptorchids, and ewes were all together and introduced at different times to the group in Farm 2.  These animals were biopsied two months before slaughter, a month before, and post-rigor. On-farm, large inter-individual variation in muscle glycogen was observed in both farms but no significant difference in true glycogen between farms. Muscle glycogen levels seemed to fluctuate from one biopsy to another, contrary to previous belief that it remains constant throughout. There was no significant difference in HSP20 between farms and no correlation between muscle glycogen and HSP20 was observed. Post-rigor, 66% of carcasses from Farm 2 had high pHu (≥5.8), compared to none from Farm 1. This may be due to stress brought about by exaggerated behaviours of rams (e.g. aggression and chasing) during close confinement at lairage. However, more observations on-farm and at lairage are needed. Lastly, 69 loin samples of varying levels of residual glycogen were tested for drip loss, (WBC), fat, protein, and microbial content a day post-rigor (Day 1) and again after eight weeks (Week 8). Results showed no correlation between residual glycogen content and any of the parameters tested at either time points. A decrease in total glycosyl units at Week 8 was observed but no decrease in true glycogen levels. This was likely due to microbes use of free glucose as a food source. 

To conclude, the results of this study suggests that the co-habitation of intact rams and ewes on-farm causes stress, which is compounded by the close confinement at lairage, leading to high pHu of their carcasses. It is, therefore, recommended that, although intact rams have higher saleable weight, these rams be castrated before mixing with other rams and ewes to avoid high pHu and, hence, provide good quality meat and less stressed animals (better animal welfare). The fluctuation in muscle glycogen levels over time does also need closer scrutiny.

text: Identifying causes of high pH in lamb meat Lamb meat export is a multi-billion-dollar New Zealand industry. Therefore, strategies to maintain and improve quality have immediate commercial benefit. Consumers judge quality by colour, tenderness, and flavour, all of which are affected by ultimate pH (pHu). Ideal meat pHu is 5.5 and is influenced by muscle glycogen concentration. Insufficient muscle glycogen at slaughter results in high pHu (>5.8) which results in tough meat, dark colour, and shorter storage life. The decrease in meat pH post-slaughter is caused by the build-up of H+ ions as a consequence of anaerobic glycolysis of glycogen for ATP formation. Physical stress depletes muscle glycogen, prompting consumers to conclude animal mistreatment. However, stress, does not necessarily equate to abuse as all animals experience some level of pre-slaughter stress and any negative effects depend on duration, type, intensity, and susceptibility. Studies have focused on post-farm-gate stressors (e.g. transport and lairage) but less clear is the role of on-farm stressors on the incidence of high pHu. The aim of this study was to investigate the variation of muscle glycogen of lambs on-farm, examine the use of heat shock protein 20 (HSP20) as a marker for physiological stress, and determine any relationship between residual glycogen level and meat quality attributes such as water binding capacity (WBC), drip loss, microbial abundance, fat, protein, and water content.  

Two observations were conducted. Firstly, 60 animals from 2 farms with different production systems: wethers (castrated males) were raised with ewes in Farm 1, whereas, intact rams, wethers, cryptorchids, and ewes were all together and introduced at different times to the group in Farm 2.  These animals were biopsied two months before slaughter, a month before, and post-rigor. On-farm, large inter-individual variation in muscle glycogen was observed in both farms but no significant difference in true glycogen between farms. Muscle glycogen levels seemed to fluctuate from one biopsy to another, contrary to previous belief that it remains constant throughout. There was no significant difference in HSP20 between farms and no correlation between muscle glycogen and HSP20 was observed. Post-rigor, 66% of carcasses from Farm 2 had high pHu (≥5.8), compared to none from Farm 1. This may be due to stress brought about by exaggerated behaviours of rams (e.g. aggression and chasing) during close confinement at lairage. However, more observations on-farm and at lairage are needed. Lastly, 69 loin samples of varying levels of residual glycogen were tested for drip loss, (WBC), fat, protein, and microbial content a day post-rigor (Day 1) and again after eight weeks (Week 8). Results showed no correlation between residual glycogen content and any of the parameters tested at either time points. A decrease in total glycosyl units at Week 8 was observed but no decrease in true glycogen levels. This was likely due to microbes use of free glucose as a food source. 

To conclude, the results of this study suggests that the co-habitation of intact rams and ewes on-farm causes stress, which is compounded by the close confinement at lairage, leading to high pHu of their carcasses. It is, therefore, recommended that, although intact rams have higher saleable weight, these rams be castrated before mixing with other rams and ewes to avoid high pHu and, hence, provide good quality meat and less stressed animals (better animal welfare). The fluctuation in muscle glycogen levels over time does also need closer scrutiny.

year: 2018

title: Ngā Wai E Rere Nei: The Physical and Symbolic Representations of Embodied Waters of Birth and Mourning

authors: Dixon, Ngahuia Mereana

subjects: Women water procreation tears

abstract: Recently, there has been considerable public debate and much consternation, especially amongst Māori, about the future New Zealand’s waterways. Māori have strongly held views, tikanga and cultural knowledge, about waterways and their deep connection to iwi (tribal/community) identity, history and sense of well-being. The waterways in public discussion are lakes, rivers, harbours and the ocean.  
This thesis examines deeper aspects of tikanga that relate to Māori concepts of waterways and oceans, but more specifically to the waterways of the human body which I refer to as embodied waters.  Māori cultural concepts of water and tikanga that is applied to water, is interconnected to the wider body of knowledge or mātauranga, in which water, is fundamental to concepts of human and environmental life and death. The thesis examines the tikanga, meaning knowledge, values and practices, regarding the embodied waters, related to human procreation and death. 
The research examines the rich Māori knowledge base, relating to concepts such as te whare tangata, waiū, te ūkaipō, roimata and hupe which still have symbolic and material significance in Māori beliefs, values and practices. The research drew upon kaupapa Māori research approaches, as a way to examine tikanga, from a contemporary Māori perspective. My research examined recorded oral traditions and literatures, including whakatauākī, whakapapa, waiata mōteatea, haka and pūrākau, alongside other research literature in the field. The research approach also included an auto-ethnographic component that has enabled me to connect my own observations and practices, with this literature, to demonstrate how tikanga in relation to this knowledge is applied. The research focuses on two main iwi contexts, Tauranga where I was born and raised, and Waikato, where I have lived since I married into the iwi.   
The thesis reveals the interconnected philosophies, cultural concepts, values and practices that are embedded in language, rituals, traditions, stories and symbols. I argue that these tikanga, give coherence and guidance, to contemporary practise especially in the context of cultural revitalization, where communities are seeking to restore certain tikanga. The thesis also finds that the tikanga relating to embodied waters, for human life and death, still give meaning to the people and communities, who continue to adhere to tikanga, those traditions providing a cultural framework for understanding their identity.

text: Ngā Wai E Rere Nei: The Physical and Symbolic Representations of Embodied Waters of Birth and Mourning Recently, there has been considerable public debate and much consternation, especially amongst Māori, about the future New Zealand’s waterways. Māori have strongly held views, tikanga and cultural knowledge, about waterways and their deep connection to iwi (tribal/community) identity, history and sense of well-being. The waterways in public discussion are lakes, rivers, harbours and the ocean.  
This thesis examines deeper aspects of tikanga that relate to Māori concepts of waterways and oceans, but more specifically to the waterways of the human body which I refer to as embodied waters.  Māori cultural concepts of water and tikanga that is applied to water, is interconnected to the wider body of knowledge or mātauranga, in which water, is fundamental to concepts of human and environmental life and death. The thesis examines the tikanga, meaning knowledge, values and practices, regarding the embodied waters, related to human procreation and death. 
The research examines the rich Māori knowledge base, relating to concepts such as te whare tangata, waiū, te ūkaipō, roimata and hupe which still have symbolic and material significance in Māori beliefs, values and practices. The research drew upon kaupapa Māori research approaches, as a way to examine tikanga, from a contemporary Māori perspective. My research examined recorded oral traditions and literatures, including whakatauākī, whakapapa, waiata mōteatea, haka and pūrākau, alongside other research literature in the field. The research approach also included an auto-ethnographic component that has enabled me to connect my own observations and practices, with this literature, to demonstrate how tikanga in relation to this knowledge is applied. The research focuses on two main iwi contexts, Tauranga where I was born and raised, and Waikato, where I have lived since I married into the iwi.   
The thesis reveals the interconnected philosophies, cultural concepts, values and practices that are embedded in language, rituals, traditions, stories and symbols. I argue that these tikanga, give coherence and guidance, to contemporary practise especially in the context of cultural revitalization, where communities are seeking to restore certain tikanga. The thesis also finds that the tikanga relating to embodied waters, for human life and death, still give meaning to the people and communities, who continue to adhere to tikanga, those traditions providing a cultural framework for understanding their identity.

year: 2013