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A quantitative survey of consumer perceptions of smart food packaging in China
Get PDFThis study quantified the acceptability of smart food packaging technologies and determined their associations with sociodemographic, attitudinal, and behavioral characteristics of consumers in China. Two quantitative surveys were conducted using an intercept method in Beijing with one for intelligent food packaging and the other for active food packaging. Chi-square tests of independence and contingency tables were used to determine the acceptability of smart food packaging and significant associations with multiple variables. Smart packaging was accepted by 56% of participants in both surveys. Marital status and employment status were associated with the acceptance of active packaging, while consumer interactions with current food packaging were associated with the acceptance of intelligent packaging. Acceptance of both active and intelligent packaging was associated with trust in multiple institutions. This study is the first to provide broad information about Chinese consumers' acceptance of smart packaging technologies for food products. Findings from this research can contribute to further detailed consumer studies in product-specific packaging designs
Subsistence in the Lapita Homeland
No full textThis thesis presents an analysis of vertebrate fauna remains from two Lapita sites in the Arawe Islands of the Bismarck Archipelago, Papua New Guinea. Studies of subsistence in Pacific contexts have focussed on how Lapita peoples and their descendants were able to successfully settle the islands of Remote Oceania. Exploitation of existing resources and elements of transported landscapes are prominent themes in such research. However, subsistence in Lapita contexts from Near Oceania has not received the same level of attention. This thesis addresses this imbalance in the current view of Oceanic subsistence by investigating an assemblage from the Bismarck Archipelago, where Lapita is argued to have emerged. The fauna from the sites Adwe and Apalo represent subsistence activities from the Early and Middle Lapita periods. Through zooarchaeological analysis, and interpretation drawing from various areas of research, the Arawe Islands assemblage provides an opportunity to address questions regarding the nature of subsistence during a foundational phase in Oceanic prehistory, as well as to address debates regarding the nature of introduced elements of Lapita subsistence
Chinese Consumers’ Perceptions of Functional Foods: A Netnography Study of Foods that Help the Immune System Recover from Air Pollution
Get PDFIn China, persistent and severe episodes of poor air quality have raised the population’s awareness of the deleterious impact that air pollution can have on their health and lead many people to explore physical means to limit their exposure to air pollution and therapies to help their immune system cope with this stress. Using a netnographic approach we explored Chinese consumers’ understandings of the impacts on their health caused by air pollution, and the key attributes (expected benefits, forms, and patterns of consumption) they expect of functional foods designed to help them recover from the pollution-driven impact. Relevant Chinese consumers’ discussions were selected from two Community Question Answering websites, “Zhihu” and “Baidu Knows”. The impact of pollution on the respiratory system was considered to be of the most concern and homemade TCM therapies and diet adjustment were the main forms of remedies discussed online. Results from this study will support the commercial success of functional food products designed to help Chinese consumers recover from the impact of air pollution on their health
Biogeochemical cycling of trace metals in shelf regions: The importance of cross-shelf exchange
No full textMarine phytoplankton form the base of the marine food web and are fundamental to the efficiency of the ocean’s ‘biological pump’. The biological pump is especially important in the homeostasis of atmospheric CO2 levels through the sequestration of carbon into the deep ocean via organic matter production in the surface ocean that utilizes metalloprotein enzymes or intermediates. Some of these metals are present at very low concentrations in the oceans, potentially limiting phytoplankton productivity, which has a significant effect on global carbon and climate cycles.
The primary processes controlling trace metal concentrations and distributions in the ocean are a combination of external inputs and removal processes, as well as internal recycling processes. The extent of these processes varies in different oceanic regions but generally they are all prominent in shelf locations. In particular, the recent increase in meltwater input from declining sea-ice and glaciers supplies the Southern Ocean with freshwaters containing additional sources of some trace metals. During the austral spring in the Western Antarctic Peninsula region, a substantial input of Fe into shelf surface waters occurred by meltwater input and sea-ice formation, and into shelf bottom waters by non-reductive sedimentary processes. However, the characterization of distinct meltwater sources is not well constrained to differentiate the sources of Fe-enriched meltwater. High precision isotopic analysis of the conservative element uranium (U) resolved subtle variations in the 234U/238U isotope ratio (reformulated into delta-notation as δ234U) and a linear correlation between δ234U and salinity in the Dotson-Getz Trough region, West Antarctica. A three-component mixing model using δ234U and salinity of possible endmembers predicts that glacial meltwater and Antarctic stream waters are the most likely freshwater sources that, in combination with sea-ice meltwater, control the observed δ234U – salinity variations in the Dotson-Getz Trough region, potentially in other shelf regions of Antarctica as well.
The importance of intruding open ocean waters and interaction with ice shelves as a source of trace metals to high-latitude shelf regions is apparent, but the influence of shelf processes on trace metal distributions in other oceanic regions remains limited, especially in low-nutrient, stratified waters, such as those across the northeastern continental shelf of New Zealand. This continental shelf, overlain by waters of the Hauraki Gulf, is relatively narrow and temporal variation in these processes, such as localized upwelling and the extent of subsurface water intrusion, results in the observed inter-annual variability in the concentrations and distributions of trace metals across the northeast continental margin of New Zealand.
These studies demonstrate the importance of cross-shelf exchange in connecting shelf and open ocean waters, and the profound influence this has on the regional and global concentrations and distributions of trace metal micronutrients. If the current trend of climate warming continues, it will result in increased rates of ice melt and elevated water temperatures. This will likely lead to stronger stratification, weakening vertical diffusivity between the surface water layer and the water beneath the pycnocline, which could drive surface water microorganisms into (micro-) nutrient limitation, resulting in a decreased efficiency of the global biological pump
Expanding the utility of the zinc and cadmium stable isotope micronutrient proxies, and reconstructing palaeo-productivity through the last deglaciation
No full textThe oceanic biogeochemical cycling of trace metal micronutrients is being progressively developed to assess the efficiency of the ocean’s ‘biological pump’, atmospheric carbon dioxide (CO2) sequestration, and ocean-atmosphere climate cycling due to their biological importance to phytoplankton growth and marine primary production. Technological advancements have facilitated investigations into the micronutrient biogeochemical cycling in the modern ocean using seawater samples, and in the past oceans using mineral archives that retain a seawater component at the time of formation. These developments have recently enabled the use of micronutrient stable isotope systems to reconstruct variations in the coupling between the ocean’s ‘biological pump’ and carbon-climate cycling throughout Earth’s history, with enhanced resolving power compared with concentration analyses alone.
In this thesis, the utility and accuracy of the zinc (Zn) and cadmium (Cd) isotope micronutrient systems is vastly expanded for accurate reconstructions of past seawater and marine primary productivity. To achieve this, four primary objectives were targeted. First, a scarcely utilised ‘double-spike’ design was used to obtain enhanced analytical resolution, required to accurately document subtle but distinct isotope fractionation that is typical of the Zn isotope system in seawater. To this end, up to a factor of four improvement in measurement precision is routinely attained by implementing a 70Zn-67Zn double spike design, compared with traditionally used double spikes, while accuracy is maintained across a range of Zn load sizes and matrix types. New and refined Zn isotope values for a suite of certified reference materials and standards are provided for use across multiple emerging disciplines, and the analytical improvements could be essential for documenting previously unresolvable biogeochemical processes.
Second, the utility of commonly used carbonate chemical cleaning protocols, and the effects of partial carbonate dissolution on recent Holocene (<11,000 year old) surface carbonate sediments and an ancient Mesozoic (~94 million year old) carbonate sediment, was interrogated for Zn and Cd isotope analysis. This study demonstrates that accuracy is improved by using carbonate chemical cleaning methods that selectively remove contaminating secondary iron-manganese (Fe-Mn) (oxyhydr)oxide phases. However, the ‘reductive step’ required to achieve this could induce anomalous zinc isotope fractionation and must be carefully monitored. Natural and laboratory-controlled partial carbonate dissolution is also shown to cause Zn and Cd isotope fractionation. This study provides an evidence-based approach to selecting the methodological protocols that can be used to obtain accurate Zn and Cd isotope analysis in carbonates. Furthermore, this study highlights that partial carbonate dissolution must be accounted for, or avoided, in Zn and Cd isotope palaeo-productivity reconstructions across all time periods.
Third, a suite of seven Holocene surface carbonate sediments retrieved from the New Zealand and southeast African continental margins were used to construct, for the first time, full water column calibrations between the Zn and Cd isotope composition of carbonates, and modern seawater. In particular, an in-depth study of the Zn and Cd isotope systematics of individual species of foraminifera, and the zooplankton and phytoplankton fractions, as well as the typically used bulk sediment fraction, was conducted. These sediments were obtained from either side of the subtropical frontal zone in the Southern Ocean that provides a natural laboratory to investigate the systematics of Zn and Cd isotopes in past seawater across a wide range of physical and chemical conditions. Biogenic carbonates record a Cd isotope signature that is systematically offset from seawater towards lighter isotopic compositions and is largely insensitive to Cd concentration. Upon correction for these isotope effects, the seawater Cd isotope signature can be accurately reconstructed. The Cd isotope composition of secondary Fe-Mn (oxyhydr)oxide coatings precipitated on the primary foraminifera carbonate surface is unfractionated relative to the seawater, providing an estimate for the Cd isotope composition of the bottom water overlying each site. Carbonates record a systematically heavy Zn isotope composition relative to seawater and require correction for the concentration dependence of isotope fractionation associated with adsorption. Accurate correction for these Zn isotope effects allow the seawater signature to be reconstructed. Furthermore, particulate organic matter is shown to represent a sink for light Zn and Cd isotopes. The magnitude of this isotopically light sink is capable of balancing the Zn and Cd sources to the oceans from riverine and atmospheric inputs.
Finally, the novel Zn isotope system was applied, for the first time, as a micronutrient palaeo-productivity tool in down-core carbonate sediment samples from the southeast African continental margin, a region that is highly sensitive to changes in southern and northern hemisphere climate change. The zinc/calcium and Zn isotope compositions of carbonates are used to demonstrate that the southeast Indian Ocean was depleted in Zn during the Last Deglaciation that occurred from ~21 to ~11 thousand years ago (ka), but variations in the regional hydroclimate during the following Holocene interval increased the supply of nutrients to the mixed layer increasing primary production. The position of the subtropical front, south of Africa, is shown to have shifted southwards since the Last Glacial Maximum at ~21 ka, which could have accelerated northern hemisphere deglaciation and strengthened Atlantic Meridional Overturning Circulation. Finally, periods of micronutrient depletion and repletion at the northern margin of the Southern Ocean correspond to abrupt ocean-climate reorganisations during the Last Deglaciation.
The enhanced resolving power and high sensitivity of the Zn and Cd isotope micronutrient systems, compared with elemental concentrations alone, will make these palaeo-productivity proxies indispensable for constraining carbon and climate cycling mechanisms in Earth’s past that can be used to better predict possible future climate scenarios
Young Chinese and Functional Foods for Mobility Health: Perceptions of Importance, Trust, and Willingness to Purchase and Pay a Premium
Get PDFConsumers’ desire to enhance diet and health has become a driver for the development of functional food products. China, with one of the largest markets in the world, offers huge potential for these foods. In the context of functional foods, specifically related to mobility health, this study aimed to understand Chinese consumers’ perceptions of the importance of these foods, trust, and willingness to purchase and pay a premium for such foods. A mixed-methodological approach using both focus groups and a survey was used to collect data from Chinese living in New Zealand. Findings show Chinese consumers place a high level of importance on their mobility health. Level of importance increased when asked about the believed importance of this area later in life. Key factors influencing Chinese consumers’ willingness to purchase functional foods were also identified: the carrier/nutrient combination; trust in the product’s country of origin and in the various institutions that may be involved in the production of functional food products; trust in both the product brand and how it is advertised; health motivation; and price. The study offers the food industry insights into the development and marketing of mobility-related functional foods targeted to this market
Environmental geochemistry of mine waste and waters at Macraes gold mine, Otago
Get PDFThe mineralogy and geochemistry of mine waste can determine the mobility of elements into the wider environment. This research covers four phases of mine waste at Macraes, an active orogenic gold mine in Otago, New Zealand. It encompasses the generation of mine waste in pressure-oxidation autoclave processing, the evolution of tailings in storage, how water-rock interactions in waste-rock influence water chemistry, and treatment methods for high sulphate water affected by tailings and waste rock.
Arsenopyrite (FeAsS), pyrite (FeS2), and for a time stibnite (Sb2S3), were processed by a pressure oxidation autoclave at Macraes, which changes the nature of the waste to oxidised material. Handheld XRF and SEM-EDS analyses were used to characterise the scales formed in the autoclave, focusing on the mineralogy of arsenic (As) and antimony (Sb). Results show that Sb may form the insoluble oxide tripuhyite (FeSbO4) with co-precipitated As in the autoclave. This may explain why Sb concentrations did not increase in waters at Macraes when the mine was processing externally mined Sb rich ore.
The geochemistry and mineralogy of the tailings is studied to assess how the autoclave influences tailings mineralogy, attenuation and leaching processes over 10-20 years of burial. Most sulphides (arsenopyrite and pyrite) in 77 m deep tailings appear unaltered since deposition. More recent tailings (44 m depth and surface) have had most sulphides oxidised by the autoclave during processing. At these shallower depths arsenic was primarily associated with ferric oxides and some ferric arsenate but some arsenopyrite and pyrite was present, unoxidized by the autoclave.
Extensive water quality data from 20 years of water analysis has been used to assess the water-rock interactions occurring in the waste rock stacks and tailings. In waste rock stacks pyrite weathering produces sulphuric acid, which is neutralised by chlorite and calcite in the waste rock stacks, leaving high concentrations of sulphate (~2800 g/m3), magnesium (~800 g/m3) and bicarbonate (~700 g/m3) in solution.
Calcium:bicarbonate and magnesium:sulphate ratios have been identified as markers for identifying tailings influenced water from waste-rock influenced water at Macraes.
A proposal to manage high sulphate waters at the site through irrigation to force precipitation of sulphate minerals such as gypsum is investigated. The composition of the precipitates formed in a waste-rock stack affected waterway were found to be primarily aragonite, but geochemical models showed that with enough evaporation, gypsum would precipitate. A laboratory irrigation trial found that gypsum did precipitate in soil, but sulphate concentrations regained near-original levels in drainage after 8 weeks of irrigation.
The arsenic and antimony in the tailings appear geochemically stable, with any aqueous components being adsorbed to the abundant ferric oxyhydroxides produced in the autoclave, but high sulphate water from waste rock and tailings is a remaining issue at the site
Maternal High Fat Diet and Myelination within the Basolateral Amygdala and Hippocampus
Get PDFMaternal obesity has significant effects on the neurodevelopmental outcomes of the offspring, increasing their propensity to neurodevelopmental disorders (NDDs) such as Autism Spectrum Disorders (ASDs). ASDs emerge from disturbances in the developing ‘social brain’. This includes the amygdala (BLA) and hippocampus (HP) which contribute to the regulation of emotions, social behaviours, and memories.
Disturbances to myelination of these regions during development are thought to be central to the origins of ASDs. Oligodendrocytes (OLs) are responsible for myelination within the central nervous system, providing means to regulate the timings of signals propagating throughout the brain. This is essential during neurodevelopment, through mechanisms of spike timing dependent plasticity. If these mechanisms were undermined and the ability to regulate the temporal propagation of information lessened, such as by myelinogenic disturbances, circuits would have a greater propensity to develop improperly.
Disturbances in the timing of myelination during development may be one of the mechanisms linking maternal obesity to the offspring’s increased risk to ASDs. It was hypothesised that OL development may be disrupted in the BLA and HP, in the offspring of obese mothers. To investigate this, OLs were analysed in offspring of control and maternal high fat diet (mHFD) fed dams, as a mouse model of maternal obesity. At postnatal day 16 (P16), the BLA and HP were labelled for Olig2, a pan OL marker, and MBP, a mature OL marker. At P30, the HP was labelled for Olig2 and MBP. The number and density of Olig2-immunoreactive (IR) cells were calculated, reflecting the size of the total OL lineage. MBP-IR integrated pixel densities (IntDen) were calculated, as a proxy measure for levels of myelination. The number and density of mature OLs, identified through the colocalization of Olig2 and MBP, were also calculated at P16.
The number of OLs within the BLA was unchanged between the control and mHFD offspring at P16. Likewise, MBP-IR IntDen, a measure of myelination, was unchanged between the maternal diet groups. Thus, the OL lineage in the BLA appears unaffected by maternal nutritional adversity in utero. By contrast, MBP-IR IntDen was significantly reduced within the HP of the mHFD offspring at P16. While the total number of OLs was unchanged, there were fewer mature OLs in the HP of the mHFD offspring. Myelination however appeared to normalize with age, as no differences in the number of OLs or MBP-IR IntDen were observed in the HP between the control and mHFD offspring at P30. Thus, myelination of the HP is delayed in the mHFD offspring, likely due to maturational impediments, but normalizes to reach completion.
These data provide insight into the regional effects of maternal obesity on myelination in the offspring. Disturbances during hippocampal myelination may contribute to neural circuit dysfunctions that are seen at an increased incidence in the offspring of obese mothers. Further work is necessary to gain understanding of the mechanisms underpinning these changes in development, and the predisposition to poor health and NDDs, in the offspring of obese mothers
Taking science communication to school: Improving student engagement with science through mobile filmmaking
Get PDFOur lives are increasingly influenced by science. Global challenges like climate change, disease, and agriculture all rely on the public making informed decisions through engagement with scientific practice and information. Unfortunately, there is a growing disillusionment with science, which can be initiated early in life depending on the quality of school science experiences. Decades of international evidence has found that students become less engaged with science as they progress from primary to secondary schooling. Little has been done to examine or address these trends in the context of science education in Aotearoa New Zealand. Engagement in science has been related to positive student outcomes in learning and life, highlighting an urgent need to propose interventions to tackle the decline. Hooking students’ situational interest or switching on their established interests are credible strategies for establishing engagement. Student generated digital media offers a strategy to hook adolescent students’ existing technological and social interests in order to switch-on their engagement with science.
This doctoral research investigated the current state of student engagement with science and analyses the impact of student generated mobile filmmaking on science engagement in the middle years classrooms in New Zealand (Years 7-10, ages 11-15). A two-phase explanatory sequential mixed-methods approach was taken to address the research questions. An initial quantitative survey (Phase I) informed the development, implementation, and qualitative analysis of a mobile filmmaking science class activity aimed at improving student engagement with science (Phase II). The research is presented in the style of a thesis with publications, spread across three manuscripts.
Survey results (Phase I, n=429 students) indicated that the characteristic ‘decline’ in science engagement over the early adolescent years was only evident when asked specifically asked about school science. When asked about science outside of school or in their future study or career, older students were more engaged with science than younger students. Interventions which are contextualised and relevant to students’ everyday lives and futures will be more effective in improving engagement with science.
The Science Video Project (Phase II, n=4 classes) aimed to appeal to students’ existing interests in technology and group-related activities relevant to everyday life such as video-production for social media as a way to improve their engagement in science. Case study data from teacher interviews, student group interviews, questionnaires, and observations found that mobile filmmaking greatly improved student engagement with science compared to typical class activities, especially improving students’ emotional engagement. Mobile filmmaking also gave teachers the opportunity to achieve cross- curricular learning in literacy, digital technologies, and personal developmental skills. Furthermore, the students’ high digital literacy with filmmaking on mobile devices allowed educators to overcome concerns about using devices in the science classroom.
Taken together, this research finds that making students the science communicators through mobile filmmaking is an effective and easy way to improve science engagement in middle years classrooms. With this established, future research is encouraged to measure (i) the associated learning outcomes for mobile filmmaking, and (ii) longitudinal effects of repeated opportunities to create mobile films
Is Goal-Conflict Specific Rhythmicity a Clinically Valid Biomarker for an Anxiety Syndrome?
Get PDFAnxiety disorders are the most common group of mental disorders in Aotearoa New Zealand. Despite the high disease burden associated with anxiety disorders, there are currently no objective biomarkers that can aid their diagnosis. Goal-conflict specific rhythmicity (GCSR) is proposed to be the first electroencephalographic (EEG) biomarker for a neural process contributing to clinical anxiety. Previous studies have shown GCSR to be anxiolytic sensitive and increased in clinically diagnosed patients, but no one has compared GCSR between patients and age-matched controls. The aim of the current thesis was to investigate the clinical validity of GCSR within patients diagnosed with DSM-IV-TR anxiety disorder diagnoses. We hypothesised that clinically diagnosed patients would show stronger GCSR than controls; high anxiety, indexed by Spielberger’s State-Trait Anxiety Inventory – Trait (STAI-T) items, would be linked to increased GCSR; and no specific DSM-IV-TR anxiety disorder diagnosis would show stronger GCSR than other diagnoses. Goal-conflict specific rhythmicity of 79 participants recruited from Student Job Search (SJS), 53 untreated patients from the community, and 35 healthy controls from the community were recorded at F8. The first analysis compared GCSR between SJS participants with high, medium, and low STAI-T scores. Participants with high STAI-T scores produced moderately stronger GCSR than the other two groups; the difference was statistically significant between the high STAI-T and medium STAI-T groups. In the second analysis, GCSR was compared between patients with DSM-IV-TR anxiety disorder diagnoses and healthy controls. Patients diagnosed with DSM-IV-TR anxiety disorder diagnoses showed stronger GCSR than the control group; however, no significant differences in GCSR were found between patients with different STAI-T scores. To investigate whether the lack of difference between the two patient groups was due to STAI-T not being a pure measure of anxiety, multiple regression analyses were carried out using the Anxiety and Depressivity scores from the Personality Inventory of DSM-IV-TR (PID-5) and the Neuroticism score from the Eysenck Personality Questionnaire Revised (EPQ-R) to predict STAI-T scores. In line with my prediction, Neuroticism, PID-Anxiety, and PID-Depressivity scores were found to be significant predictors of STAI-T. In the final analysis, GCSR was compared between patients with different primary DSM-IV-TR anxiety disorder diagnosis: pure generalised anxiety disorder (GAD), social anxiety disorder (SAD), comorbid GAD and major depressive disorder (MDD), and a group of pooled other diagnoses (e.g., panic disorder, post-traumatic stress disorder). Contrary to my expectations, patients diagnosed with comorbid GAD and MDD had significantly higher GCSR, different from the other diagnosis groups. Although this thesis is not without limitations, it is among the first to directly compare GCSR between DSM-IV-TR anxiety disorder diagnosed patients and controls. These results provide evidence that GCSR is a human biomarker for a process related to clinical anxiety