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Sea Level Rise in New Zealand:The Effect of Vertical Land Motion on Century‐Long Tide Gauge Records in a Tectonically Active Region
No full textHistorically tide gauge (TG) data have been used to estimate global sea level rise. Critical to the analysis of TG records is the assumption that the TG sites are stable and not affected by vertical land motion (VLM). We analyze century‐long TG records from New Zealand that have been affected by VLM due to both major and transient earthquake events at a regional level as well as local instabilities. Using combined GPS and precise leveling, we estimate relative VLM between the GPS and TG of up to 1 mm/year. Based on 15–20 years of GPS data, the effect of seismic activity and slow slip events has uplifted sites by up to 0.8 mm/year on average in Wellington and Dunedin. Updated estimates of long‐term relative sea level (RSL) at four New Zealand TGs, as well as an estimate of RSL at a new fifth TG (New Plymouth), are determined using data through 2013—an additional 13 years compared to the previous study. The VLM corrected RSL rates gives our best estimate absolute sea level of +1.45±0.28 mm/year (1891−2013). It is important that absolute sea level derived from RSL rates include realistic estimates of VLM, especially at TG sites that are close to plate boundaries, located in seismically active regions, affected by glacial isostatic adjustment, land ice loss, or gas/oil/water extraction.Peer Reviewe
An eye on coastal change: Characterising spatio-temporal coastal sensitivity at high-resolution - Okia Reserve, Otago Peninsula, New Zealand
No full textNatural coastal systems exhibit dynamic behaviour and are sensitive to a range of forces. This sensitivity is projected to change in the context of climate change. Advanced coastal monitoring techniques can detect and characterise modifications in the coastal environment in unprecedented spatial detail, across a relatively wide spatial area. Repeated use of high spatial resolution remote sensing technologies such as Remotely Piloted Aircraft Systems (RPAS) and Light Detection and Ranging (LiDAR) allowed a spatio-temporal signal of the evolution of both the vegetation and geomorphology at the 231 ha Okia Reserve (Otago Peninsula, Dunedin) to be measured across short (14 months) and long (12.5 years) temporal scales.
The Okia Reserve is an important ecological site with rare flora and fauna, including breeding habitats for endangered Yellow-eyed Penguins (Megadyptes antipodes) and New Zealand Sea-lions (Phocarctos hookeri). It also contains a nationally significant archaeological site along the southern edge of the site. This research mapped changes between September 2004 and March 2017, and between March 2017 and May 2018. Three-dimensional change detection techniques are used to quantify significant spatiotemporal changes over each period. These changes supported a fine-scale assessment of the sensitivity of both the vegetation and geomorphology at Okia Reserve, as well as a projection of potential effects of sea-level rise.
The short-term sensitivity assessment showed significant inlet/vegetation edge and volumetric erosion around the southern edge of the reserve at Papanui Inlet, much of it focused on a nationally significant archaeological site. Temporal comparison with the long-term results confirmed significant unabated inlet/vegetation edge and volumetric erosion at Papanui Inlet, in the order of 0.8 – 1 m/yr. Analysis of the projected impact of coastal inundation and flooding further emphasised the impending exposure of the nationally significant archaeological site, with the southern end of the reserve likely to be impacted by direct coastal inundation as early as 2050.
Results in other areas such as Papanui Inlet Spit and Victory Beach suggest a state of dynamic equilibrium with accumulation, erosion and likely redistribution of sediment. Victory Beach itself displayed a similar magnitude of nett volumetric change (approx. -10000 m3) over both the 14-month and 12.5-year time periods. Both periods also displayed a sustained growth rate in vegetated areas.
Observed wetlands and flooding indicated further dynamic behaviour in the coastal system as a response to seasonal variability and storm events. High-resolution quantification of anthropogenic interactions within the reserve accurately highlighted the magnitude and extent of localised changes to vegetation and topography as a result of some of these activities (e.g. vehicle access track maintenance and new tracks).
The combination of accurate high-resolution topography, analysis of tidal levels and the effect of four sea-level rise scenarios showed the southern end of the reserve is particularly at risk to direct coastal inundation and indirect flooding with the potential of significant modification to natural habitats and endangered wildlife breeding sites, as well as impedance to vehicle and pedestrian access
Military Medicines: ANZAC Military Pharmacy, 1914-1918
No full textMilitary pharmacy is a niche subset of the wider pharmacy profession. As a small component of the armed forces, the role encompasses unique military requirements beyond usual pharmacy practice. This thesis analyses the role and experience of New Zealand and Australian pharmacists who served as pharmacists during World War I (WWI), rather than as soldiers in combatant units. This history of the pharmacists of the Australian and New Zealand Army Corps (ANZAC) also provides a window into a little-recognised sector of the armed forces: supply and support. It argues that the role expectations of military pharmacists did not align with those of other serving health practitioners during the war, and that these disparities had their genesis in professional and social tensions within the civilian sphere.
Historically, pharmacists have served as unseen or ‘silent’ specialist health professionals within military contexts. In this thesis, I consider social and cultural factors that shaped the wartime expectations of ANZAC military pharmacists throughout WWI. In particular, I examine the ‘invisibility’ of pharmacy, alongside perceptions of professionalism, educational pathway differences between pharmacists and other health practitioners, and the impact of social class and status on military rank. This analysis is based primarily on military and pharmacy records for WWI, together with period publications. A detailed database created for this thesis of all New Zealanders who served as pharmacists during the war provides case studies and conclusions to support the thesis.
In particular, I argue that the military’s position on the role and status of pharmacists derived mainly from the perception that they were ‘in trade’. This sensibility was problematic. Perceived mainly as purveyors of medicinal commodities, the role of pharmacists in maintaining the fighting strength of ANZAC forces was rarely appreciated, either during the conflict or in subsequent accounts. The supply of medicines and therapeutics as medical commodities is, however, intrinsically tied to the economics of war, which proved to be a growing concern as the conflict wore on. While New Zealand pharmacists were proscribed in their aspirations for advancement, I demonstrate that Australian pharmacists were most valued for their business skills, especially in supply, contracting, inventory control and cost savings.
Throughout WWI, the professional skills and knowledge offered by New Zealand pharmacists was not recognised through granting of commissioned rank. In Australia, honorary commissions were only granted to pharmacists later in the war, primarily for logistical and managerial roles. By being ‘in trade’, pharmacists were considered to be of the wrong social class; military structure at the time largely reserved officer status for social or professional élites. Social assets were at least as important as merit for progression through the ranks. The drive for professional recognition through the granting of commissioned rank became the dominant political issue facing New Zealand and Australian military pharmacists, shaping their experiences throughout the war. Examining the underpinning cultural and social factors is thus key to understanding the marginalisation of pharmacists within the military framework
Nicotine with speed: The role of more rapid-delivery of nicotine combined with slow transdermal delivery of nicotine for smoking cessation
No full textBackground: Smoking is the biggest cause of preventable death in industrialised countries. Quit rates after use of current Nicotine Replacement Therapy (NRT) are low. Animal studies suggest nicotine is more rewarding when it is delivered rapidly to the brain, and human clinical trials of the current NRT that delivers nicotine to the brain most rapidly (nicotine nasal spray), demonstrate quit rates are improved if it is used in combination with nicotine transdermal patches. However, nicotine nasal spray is aversive and other rapid nicotine delivery systems are required. The lung is the most rapid delivery route to the brain; however, inhalation of nicotine is aversive, and delivery of substances to the lung is technically difficult. In 2008, when these trials were designed, apart from bench-top nebulisers, waterpipes, cigarettes, and some electronic cigarettes, no device was capable of pulmonary nicotine delivery. Nicotine mouthsprays are amongst the most rapid NRT at delivering nicotine to the brain and may be more tolerable than nasal spray.
Objectives:
1. Develop a nicotine pressurised metered-dose inhaler (pMDI).
2. Test the long-term abstinence rates of active nicotine mouthspray plus active patch, and of active nicotine inhaler plus active patch, compared to placebo plus active patch.
Methods:
1. Double-blind, Randomised Controlled Trial (RCT) of active nicotine mouthspray and active nicotine patch cf. placebo mouthspray plus active nicotine patch (ZAP).
2. A cross-over, non-randomised, open-label, pharmacokinetic, pharmacodynamic, and tolerability trial of a free-base nicotine pressurised metered-dose inhaler (pMDI).
3. A cross-over, non-randomised, open-label, pharmacodynamic, preference and tolerability trial of free-base nicotine, and nicotine lactate, and the effects of flavouring, delivered by pMDI.
4. Double-blind, RCT of active nicotine lactate pMDI and active patch cf. placebo pMDI plus active nicotine patch (INHALE).
Results: Ten smokers enrolled in the pharmacokinetic trial, which showed that nicotine was delivered, at least in part, via the lung, and rapidly quenched urges to smoke.
ZAP enrolled 1,423 smokers. Nicotine mouthspray plus nicotine patch, significantly increased abstinence to six months cf. placebo and nicotine patch (15.5% vs 10.6%; p=0.006). The prolonged twelve-month abstinence was 10.1% with the active combination cf. 7.1% (p=0.045). At all follow-up time-points urges to smoke reduced significantly compared to baseline in both active and control groups, and this reduction was significantly greater in the active cf. control group. Withdrawal scores reduced at all follow-ups compared to the one-month visit in both groups, with no significant difference between groups after Bonferroni correction. The variables recorded before randomisation that were statistically significant predictors of lower rates of abstinence after Bonferroni correction were Māori ethnicity; enrolment at a Māori community trial site; previous use of NRT, and higher scores of the Social/Environmental Goads scale of the brief-WISDM psychological battery. Pre-randomisation variables significantly predictive of higher odds of abstinence were being 50 years or older; having started smoking daily aged sixteen years or older; how prepared subjects’ felt they were to handle stress without smoking; the number of subjects’ personal acquaintances who have quit.
Six variables measured after randomisation statistically decreased abstinence after Bonferroni correction: MNWS Craving score at one-, three-, and six-months post-target quit date; MNWS Negative Affect score at three-months post-target quit date; and brief-QSU total score at one- and three-months post-target quit date. Eleven variables recorded post-randomisation predicted increase abstinence: having quit on or before the target quit date; fully completed the record of CPD for the first fortnight of the trial, strongly wanting to continue trying to quit or remain abstinent and continue to participate in the trial (recorded the day after the target quit date); being highly confident that one will quit/stay abstinent (measured a day after the target quit date); how well subjects reported they were coping with their urges to smoke reported a day after the target quit date;, and how much Zonnic subjects reported using a day after the target quit date. Of the eight Likert scales conceived by the author, none predicted abstinence after Bonferroni correction for sixteen comparisons, while one was significant after correction for eight comparisons.
Twelve smokers enrolled in the preference trial; menthol nicotine lactate was tolerable.
Five-hundred-and-two smokers enrolled in INHALE. Prolonged six-months abstinence rates were 78/246 (31.71%) vs. 46/256 (17.97%), p=0.00042 in the active and control group, respectively. Subjects in the active group had a significantly greater reduction in their brief Questionnaire of Smoking Urges (QSU) scores at baseline cf. the control group, and continued to have lower scores at the one-, three- and six-month follow-ups in the active- compared to control-group. Subjects in the two groups had similar nicotine withdrawal scores (MNWS scores) at all timepoints except the active group had significantly lower scores at three- and six-months. Of the ten variables recoded at baseline that were analysed as a potential predictor of prolonged abstinence, only FTND was statistically significant, albeit, weakly significant. At every follow-up beyond a week after baseline, the number of days the inhalers were used predicted abstinence in both groups. Favourable scores on the Cigarette Evaluation Questionnaire scales used to rate the inhalers, predicted abstinence at many follow-ups for many of the scales.
Although, in the active groups, abstinence rates were significantly higher in INHALE cf. ZAP, the trials were underpowered to find a significant difference in the ORs of abstinence between the trials. In both trials, the sensory qualities of the rapid-acting NRT and its placebo equivalent, had a significant bearing on abstinence, and subject who correctly guessed their treatment assignment had higher abstinence than those who guessed incorrectly or were unsure.
Conclusions: The combination of nicotine patches and each of two rapid nicotine delivery devices assisted more smokers to quit smoking than use of nicotine patch and placebo. Further research is required to reduce the aversive sensory effects of nicotine mouthsprays and inhalers, and to find effective methods to encourage smokers to use these therapies regularly to replace the roles of smoking
The dietarian identities of adolescent females
No full textBackground: In our daily life, what we eat and why we eat certain foods have always been more than a matter of nutritional value. Instead, it had been proposed that there is an overarching concept of food-choice identity that people construct and depend on when making decisions about what to eat. Dietarian identity, defined as one’s thoughts, feelings, and behaviours with respect to one’s dietary pattern, has recently been conceptualized by Rosenfeld and Burrow (1), along with the Dietarian Identity Questionnaire as means of assessing one’s food-choice identity. No study, to date, has described dietarian identity in an adolescent population.
Objective: To assess the following aspects of the dietarian identity of New Zealand adolescent females in following their dietary pattern: centrality, prosocial motivation (the desire to benefit others), moral motivation (the beliefs of rightness and wrongness), and strictness. Secondly, to test the hypothesis that adolescent girls with strong prosocial motivation also reflect this motivation in their dietary habits by consuming less meat but more fruits and vegetables. Thirdly, to examine the relationships between the motivation subscales of dietarian identity and other variables hypothesized to be related to these motivation aspects (i.e. the ethical food choice motives).
Design: A cross-sectional, multi-centered nationwide study of New Zealand adolescent females, aged 15 to 18 years was conducted. All data were collected using self-reported online questionnaires except for anthropometry measurements. Included in the online questionnaires were four dietarian identity subscales (centrality, prosocial motivation, moral motivation, and strictness) derived from the Dietarian Identity Questionnaire by Rosenfeld and Burrow (2). Frequency of fruit, vegetables, and meat consumption to determine participants’ usual consumption; and two subscales of the ethical food choice motives questionnaire (ecological welfare and religion) by Lindeman and Väänänen (1) were also self-administered. Correlations were investigated among the dietarian identity subscales and the other variables with which they were hypothesized to be related.
Results: In general, the adolescent girls tended to view their dietary pattern as not particularly central to their identity, showed flexibility in adhering to their dietary pattern, and were motivated in their food choices towards a similar lesser extent by prosocial and moral reasons. Prosocial motivation level was also inversely associated with the girls’ usual consumption of red meat, pork, and poultry. When relationships with food choice ethical issues were examined, both prosocial motivation and moral motivation levels were shown to be positively associated with levels of concern regarding animal welfare and environmental protection.
Conclusion: The present sample of adolescent females were predominantly meat-eaters with only 6% vegetarians. Overall, these girls showed low level disagreement to “neither agree nor disagree” that the centrality, prosocial motivation, moral motivation and strictness factors were important to them in their dietary pattern. Future studies should consider exploring these concepts in a larger sample, comparing with boys, or with more aspects of the Dietarian Identity Questionnaire to better understand the self-perceptions of the adolescent population regarding their eating pattern
Insecticide contamination of streams in a warming climate
No full textFeeding a growing global population in the context of a changing climate will bring challenges for food producers and environmental managers seeking to mitigate the impact of intensifying agricultural practices. The control of insect pest populations through insecticide application is an important practice for improving crop yields, yet contamination of the environment with insecticides combined with impacts from climate change are together subjecting ecosystems to novel stressors and stressor combinations. Contamination of surface waters with neonicotinoids, the most widely used insecticides in the world, has become a chronic global problem. Despite a growing body of research investigating the impacts of neonicotinoids in aquatic ecosystems, prior to my research there were no published toxicity data for their effects on aquatic insects in New Zealand. Moreover, international data on chronic, neonicotinoid-mixture, interactive multiple-stressor and community-level effects in stream ecosystems were also lacking. My overall PhD research objective was to investigate the ecological impacts of neonicotinoid insecticides on New Zealand’s freshwater macroinvertebrate communities in a multiple-stressor and climate-change context.
I developed and optimized laboratory procedures for testing chronic toxicities of neonicotinoids and observing their lethal and sublethal effects on stream insect larvae in controlled laboratory experiments. Through a series of 4-week experiments, the chronic toxicities of three commonly used neonicotinoids (imidacloprid, clothianidin and thiamethoxam) to nymphs of the ubiquitous New Zealand mayfly Deleatidium spp. were determined (Chapter 2) and possible interactions between the three insecticides were investigated (Chapter 3). In a subsequent 6-week multiple-stressor laboratory experiment, also with Deleatidium nymphs, I focused on possible interactions of low-level imidacloprid exposure with simulated heatwaves and a period of food limitation (Chapter 4). I then conducted a stream-side mesocosm experiment in 128 flow-through stream channels to investigate the individual and combined effects of realistic, pulsed exposures of imidacloprid and raised water temperature on stream macroinvertebrate communities characteristic of fast-flowing and slow-flowing microhabitats (Chapter 5). This experiment is the first empirical evaluation of stream macroinvertebrate community dynamics in response to the world’s most widely used agricultural insecticide, increased water temperature and reduced flow velocity (simulating streams subject to reduced flows due to water abstraction and climate change). Six hundred and forty invertebrate drift and insect emergence samples each were collected throughout the experiment (on five occasions during and after the insecticide pulses), and 128 benthic invertebrate samples were collected after 24 days of heating and insecticide manipulations. In combination, the long-term laboratory experiments using larvae of a sensitive aquatic insect taxon and the field experiment in stream mesocosms allowed assessing neonicotinoid effects on stream macroinvertebrates at the individual, population and community level in a multiple-stressor and climate-change context.
The 28-day concentration-response experiments (Chapter 2) and the neonicotinoid mixture experiment (Chapter 3) revealed imidacloprid as the most toxic of the three neonicotinoids to Deleatidium nymphs and also showed its potential for synergistic interactions with the other, comparably less toxic neonicotinoids clothianidin and thiamethoxam. Imidacloprid was therefore chosen for the subsequent multiple-stressor experiments (Chapters 4 and 5). Both of these demonstrated the strong effects of raised water temperatures on stream invertebrates and especially on Deleatidium larvae. In the 42-day laboratory experiment, sublethal and lethal effects of exposure to 0.4 µg/L imidacloprid took 2436 days to manifest and were clearest in the absence of heatwaves and starvation because these stressors alone already strongly reduced Deleatidium survival. In the mesocosm experiment, all three manipulated factors strongly affected invertebrate drift community composition, with the first pulse of imidacloprid and increased temperature having a greater impact on communities in fast-flowing channels. Heating and imidacloprid exposure both generally resulted in increased emigration by drift. Increased temperature was the most pervasive stressor for the benthic invertebrate community, negatively affecting 80% of response variables. This was in part due to a natural 10-day heatwave which occurred during the manipulative period, raising temperatures in ambient mesocosms to 29.8°C and in heated channels to 32.9°C. Water temperature in the river reached 31.2°C during a second heatwave seven weeks after the end of the experiment. The snail Potamopyrgus antipodarum showed the only positive response to raised water temperatures, also responded positively to slow flow and was unaffected by imidacloprid highlighting the general tolerance of this invasive species to stressors. Monitoring drift and emergence patterns periodically throughout the experiment also provided insights into how invertebrate community composition changed in response to the natural heatwave. Taken together, the findings of my thesis demonstrate the importance of efforts to mitigate climate change and reduce contamination of surface waters with imidacloprid in order to protect our vulnerable freshwater ecosystems
The effects of ultrasound on the spread of intramuscularly injected formulations
No full textContext: The intramuscular (IM) injection is an important route of drug administration. Some researchers have suggested that the erratic rate of drug absorption from oil-based IM injections is due to variability in the spread of the formulations from the injection site. Recently, the application of ultrasound (US) has been investigated as a possible strategy to enhance the spread of IM injected formulations and thereby reduce variability in drug absorption.
Objective: The aim of the research reported in this thesis was to investigate the effects of US on the spread of IM injected formulations.
Methods: For in vitro experiments, transparent agarose gel was used as the matrix. Both Nile blue(aqueous) solution (0.001% w/w) and Nile red(oily) solutions (0.01% w/w) were prepared and injected into gels. The area of spread of injected formulations was photographically recorded and measured immediately after injection. US (1.1 MHz, 3 W/cm2) was then applied to the injection site using a 6 min on-off working cycle for 60 min after which the area of spread was measured again. Areas of spread determined as mean ± standard deviation before and after US treatment were compared. For in vivo experiments, three Wether lambs (6 to 8 months old, 32 kgs approx.) were subjected to IM injections post-mortem. Three different types of formulation (Lipiodol: ethyl esters of iodized fatty acid of poppy seed oil, 48% w/v iodine; oily suspension: barium sulfate in Miglyol 812, 30% w/w; and a self-emulsifying drug delivery system (SEDDS): mixture of Lipiodol, Maisine and Miglyol, 40:20:40%, w/w)) were prepared and two different injection volumes (1.5 and 4.5 mL) injected into muscle. US (1.1 MHz, 3 W/cm2, 100% working cycle) was applied for 0, 5 and 10 min at the injection site and the spread of formulations visualized by CT scan and measured before and after US application. The collected data was analysed using two-way ANOVA and Tukey test for post -hoc statistical analysis. Muscle tissue containing injected formulations was frozen in liquid nitrogen and subsequently examined by dissection.
Results: In the in vitro study, 60 minutes after injection, the spread of both aqueous and oily solutions remained unchanged after application of US. In the post-mortem study, the initial spread showed no significant difference between either type of formulation or injection volume. After application of US for 5 min, a significant increase in spread was observed for the oily suspension and SEDDS using an injection volume of 4.5 mL; after exposure to US for 10 min, significant increases in spread were found for the oily suspension and SEDDS at both 1.5 and 4.5 mL injection volumes. The subsequent dissection revealed a large amount of injected formulation outside the injected muscle bundle resulting from spread along the fat layer and into the inter-muscle space.
Conclusion: There is no effect of US on the spread of formulations injected into agarose gel. In the post-mortem study, the CT scan proved to be suitable to visualize the spread of IM injected formulations. The initial spread of the IM injected oil formulations showed high variation. US-induced spread was observed for the oil suspension and SEDDS. The mechanism behind the enhanced spread needs further investigation but could be related to the ability of applied US to reduce the viscosity of the injected formulations or to the transfer of the mechanical energy of US to surface energy
Intakes and main food sources of calcium for vegetarian and omnivorous New Zealand adolescent females
No full textBackground: Calcium is an essential mineral required to assist peak bone mass formation during adolescence. Calcium can only be obtained through the diet and is not widely spread throughout dietary sources with dairy products being the richest source. The last nationwide investigation of calcium intake data suggested that adolescent females were not meeting their calcium requirements, placing them at a high risk of developing osteoporosis in later life. Furthermore, vegetarian diets are becoming increasingly popular in this demographic group and, in some instances, can involve the limiting or avoidance of dairy products. The aim of the current study is to investigate the impact these food choices may have on dietary calcium adequacy and to provide updated data on the calcium intakes of adolescent females living in New Zealand.
Objective: To investigate the current calcium intake and food sources of vegetarian and omnivorous New Zealand adolescent females aged 15 – 18 years.
Design: A cross-sectional observational survey of female adolescents aged 15 to 18 years from eight different locations throughout New Zealand. Data was collected in two waves (February to April and July to September 2019). Questionnaires examining participant demographics, dietary intakes and habits (including vegetarianism) and dietary supplement use were self-administered via an online platform. Standing height and weight was measured by trained investigators to allow calculation of BMI z-scores. Dietary intake data was collected using 24-hr dietary recalls, completed on two separate occasions and entered into the dietary assessment software programme FoodWorks to calculate nutrient intakes. Usual calcium intakes were estimated using the multiple source method and the prevalence of inadequate calcium intakes calculated by the Estimated Average Requirement (EAR)-cut-point method.
Results: The study recruited 279 participants, 79.1% were of NZEO ethnicity, 15.5% Maori, 9% Asian and 6% Pacific. Most participants self-reported as following an omnivorous food pattern (87.1%) while 12.9% self-reported as being vegetarian. The median (interquartile range) usual intake of dietary calcium for adolescent females was 711 (544, 925) mg/day. The prevalence of inadequate calcium intakes was high, with 84% of the study population not achieving the EAR for calcium. No difference in calcium intakes were identified between vegetarian and omnivorous diets. Almost all (97%) of vegetarian participants had inadequate calcium intakes, however, inadequate intakes were also prevalent among omnivore participants (83%). Milk was the greatest contributor to calcium intakes (17.4%) and participants who reported drinking milk more regularly, had higher mean usual calcium intakes. The type of milk consumed varied between omnivore and vegetarian participants with cow’s milk more commonly consumed by omnivore participants and plant-based milks by vegetarian participants (81% vs 67.7%) with both groups more likely to consume whole/full fat options (76.3%).
Conclusion: These results suggest that calcium intakes of New Zealand adolescent females remain below recommended intakes, thereby increasing the risk of developing osteoporosis in later life. Milk remains the largest contributor of calcium to dietary calcium intake for both vegetarian and non-vegetarian adolescents. Following a vegetarian diet does not markedly increase the risk of inadequate calcium intakes in this sample population as the median usual calcium intakes were similar for both omnivore and vegetarian participants. The small number of vegetarian participants (12.9%) prevented examination of the calcium intakes of vegetarian participants who choose to exclude all milk and dairy products (vegans). Given the major contribution dairy makes to the calcium intakes of adolescent females, further investigation regarding the dietary sources of calcium for vegans is warranted
Magnesium Intake and Its Main Food Sources in 15-18-Year-Old New Zealand Schoolgirls
No full textBackground: Magnesium is an essential mineral. Low intakes have been widely found among dietary surveys in many industrialised countries. Magnesium intakes were not reported in the most recent New Zealand Adult Nutrition Survey (ANS 2008/09), and in the 1997 National Nutrition Survey (NNS) low intakes were consistent with that of other countries. Thus, magnesium intakes and food sources in New Zealand are not well characterized.
Objective: The overall aim is to investigate dietary magnesium intake and its main food sources within the female adolescent (15-18-year-old) population of New Zealand (NZ).
Methods: The Survey of Nutrition Dietary Assessment and Lifestyle (SuNDiAL) project is a nation-wide study investigating the intakes of vegetarian compared to non-vegetarian girls aged 15-18 years. The data presented in this thesis are from the preliminary round of collection. A convenience sample of 15-18-year- old girls was recruited from 8 different high schools within NZ. A team of 17 Master of Dietetics (MDiet) candidates recruited participants from each school with 2-3 MDiet candidates within each location. Anthropometric data (height, weight and ulna length) as well as two non-consecutive 24-hour recalls using a multiple pass system were collected, with BMI Z scores then calculated. Participants were required to complete a series of online questionnaires to collect demographic, health, dietary intake and supplement use information. 24- hour recall data were entered into the nutrient analysis programme FoodWorks 9 and the Multiple Score Method was used to generate estimated usual intakes. Food group analysis was used to describe the main food sources of magnesium.
Results: There were 145 participants who signed up from the 8 schools with an average age of 16.7 years. Of these 145 participants, 130 had both weight and height taken with 34.6% of these participants categorised as being overweight or obese. Dietary intake data were available for 132 participants with a mean energy intake of 8066kJ/day (95% CI 7754, 8379kJ/day). Magnesium intake data were slightly positively skewed and thus median intake of 280mg/day (10th percentile of 175mg/day and 90th percentile of 428mg/day) was used for this analysis. An inadequate intake level (percent below EAR) of 58.3% of participants was found. The main food sources of magnesium were bread, grains and pasta, vegetables and fruit with a mean percent contribution of 9.5, 9.4, 7.5 and 7.5% respectively. Of the girls who completed the supplement questionnaire, 4% reported taking a magnesium containing supplement daily, with an average dose of 177mg/day.
Conclusion: Data from this thesis appear to be congruent with other national surveys and convenience samples from around the world showing a mean dietary intake of magnesium below the EAR of 300mg/day, with most countries between 200-300mg/day. Most of the dietary magnesium in these other countries also came from plant-based products with some from milk, poultry and other animal-based products. Possible options to rectify a suboptimal intake include promotion of: magnesium containing supplements; magnesium rich foods; and fibre rich foods to indirectly promote magnesium intake. This research indicates further investigation is warranted to assess the magnesium intakes of this population due to these preliminary data showing a low intake of magnesium in 15-18-year-old girls in NZ
Professional learning and development in home-based early childhood education and care : exploring the benefits for educator-child shared talk and children's social emotional and self-regulatory development
No full textResearch shows that parent-child reminiscing conversations (shared talk about past events) impart benefits for children’s development across a range of domains. To date, there is limited research investigating whether reminiscing outside of parent-child context exerts similar benefits for children’s development. The current thesis sought to explore how participation in professional learning and development in home-based early childhood education and care (ECEC) impacted educators’ and children’s internal state (cognitive and emotion) language use during an educator-child reminiscing task and children’s social-emotional and self-regulatory development. In this study 17 educators and 21 children participated in at least one and up to three modules designed to support educators’ delivery of ECEC and promote children’s development. Results were analysed using a combination of visual observation methods, and statistical analyses were conducted to strengthen the conclusions drawn from findings. Overall results for educators’ and children’s language during reminiscing were inconsistent, although there was some evidence to suggest that participation in two or more modules may have promoted educators’ and children’s use of internal state language. Moreover, children who participated in the Rich Reading and Reminiscing (RRR) module demonstrated differential improvement on some measures of social-emotional and self-regulatory competence, which was evident up to two years following participation. Findings suggest that participation in RRR, which includes a reminiscing component, in home-based ECEC contexts may exert specific benefits for children’s social-emotional and self-regulatory development. Results are discussed in reference to past research on reminiscing and implications for children’s early learning and development in ECEC settings