Conference Posters

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Now showing 1 - 10 of 46
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    Acceptability of LGBTQ-Affirmative Cognitive Behavioral Group Therapy for Youth: Results from a Pilot Study
    (2023-04-01) Seager van Dyk I; Layland EK; Soulliard ZA; Pachankis JE
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    A genetic approach to identify amino acids in Gcn1 required for Gcn2 activation
    (2022-09-08) Schiemann A; Gottfried S; Sattlegger E
    The General Amino Acid Control stress signalling pathway allows cells to sense and overcome starvation. One of the major players in this pathway is the protein kinase Gcn2 found in all eukaryotic cells. Activation of Gcn2 leads to phosphorylation of the alpha subunit of eukaryotic translation initiation factor (eIF2α), which then leads to the re-programming of the cell’s gene transcription and translation profile, and ultimately allowing cells to cope with and overcome starvation. For sensing starvation, Gcn2 must directly bind to its effector protein Gcn1. This interaction is mediated via a region in Gcn1 called the RWD binding domain (RWDBD). Overexpression of the RWDBD alone impairs Gcn2 activation through disrupting endogenous Gcn1-Gcn2 interaction, hampering eIF2α phosphorylation, and consequently cells cannot overcome starvation and fail to grow.  This dominant negative phenotype is dependent on Arg-2259 in RWDBD.  Taking advantage of this phenotype in yeast, we here found that the dominant negative phenotype was reverted by each of four amino acid substitutions, K2270A, R2289A, R2297A, and K2301A.  This correlated with increased eIF2α phosphorylation levels, suggesting their relevance for Gcn2 activation.  All but Lys-2270 are fully surface exposed, suggesting that these amino acids may directly contact Gcn2.  We also found amino acid substitutions that enhanced the dominant negative phenotype of the overexpressed RWDBD, and correlated with further reduction in eIF2α-P levels.  Our findings suggest that two helices in Gcn1 constitute at least one Gcn2 contact point.
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    Why so unfit?: Assessing potential barriers to exercise adoption in middle-aged men
    (The Author(s), 2005-02-10) Towers AJ; Flett RA; Seebeck RF; Towers, AJ; Flett, RA; Seebeck, RF
    Compared to women, men:  have a higher mortality rate  consistently die younger  are more susceptible to sedentary-lifestyle related diseases (e.g., cardiovascular disease)  are more likely to engage in behaviours that increase risk of injury, disease, or death  are less likely to seek help with physical health. Despite these statistics, the amount of literature devoted to women’s health in the past two decades still greatly exceeds that devoted to men’s health. The result is that we actually know very little about what influences men’s health behaviours. Introduction We utilised the transtheoretical model of exercise behaviour change to determine the pattern of exercise adoption in middle-aged men. We also analysed whether this pattern was influenced by three potential barriers to exercise: poor self-rated health, low levels of internal health locus of control, and high perceived stress levels. Hypotheses Compared to participants in the last stage of change (maintenance), it was hypothesised that participants in the first stage of exercise change (precontemplation) would have:  lower self-efficacy  less concern over the pros of exercise  more concern over the cons of exercise  poorer self-rated health  higher levels of perceived stress  lower levels of internal health locus of control [From Introduction]
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    Sensitivity to Volcanic Field Boundary
    (2016-04-17) Whitehead M; Bebbington M; Cronin S; Moufti MR; Lindsay J
    Volcanic hazard analyses are desirable where there is potential for future volcanic activity to affect a proximal population. This is frequently the case for volcanic fields (regions of distributed volcanism) where low eruption rates, fertile soil, and attractive landscapes draw populations to live close by. Forecasting future activity in volcanic fields almost invariably uses spatial or spatio-temporal point processes with model selection and development based on exploratory analyses of previous eruption data. For identifiability reasons, spatio-temporal processes, and practically also spatial processes, the definition of a spatial region is required to which volcanism is confined. However, due to the complex and predominantly unknown sub-surface processes driving volcanic eruptions, definition of a region based solely on geological information is currently impossible. Thus, the current approach is to fit a shape to the known previous eruption sites. The class of boundary shape is an unavoidable subjective decision taken by the forecaster that is often overlooked during subsequent analysis of results. This study shows the substantial effect that this choice may have on even the simplest exploratory methods for hazard forecasting, illustrated using four commonly used exploratory statistical methods and two very different regions: the Auckland Volcanic Field, New Zealand, and Harrat Rahat, Kingdom of Saudi Arabia. For Harrat Rahat, sensitivity of results to boundary definition is substantial. For the Auckland Volcanic Field, the range of options resulted in similar shapes, nevertheless, some of the statistical tests still showed substantial variation in results. This work highlights the fact that when carrying out any hazard analysis on volcanic fields, it is vital to specify how the volcanic field boundary has been defined, assess the sensitivity of boundary choice, and to carry these assumptions and related uncertainties through to estimates of future activity and hazard analyses.
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    Exploring root traits associated with increased yield under water deficit in perennial ryegrass (Lolium perenne L.) germplasm of Mediterranean and European origins.
    (2015-10) Huassion S; Matthew C; Naeem M; Easton HS
    Exploring root traits associated with increased yield under water deficit in perennial ryegrass (Lolium perenne L.) germplasm of Mediterranean and European origins Sajjad Hussain1, Cory Matthew2, Muhammad Naeem3, H. Sydney Easton4 1Plant Genetic Resources Institute, National Agricultural Research Center, Islamabad, Pakistan, 2Institute of Agriculture and Environment, Massey University, Palmerston North, New Zealand, 3Federal Seed Certification and Registration Department, Islamabad, Pakistan, 4AgResearch, Palmerston North, New Zealand. Contact: Introduction Perennial ryegrass (Lolium perenne L.) is now one of the most widely used forage grass species in temperate pastoral agriculture and in recent years breeding for improved performance in summer drought conditions has become a focus. Germplasm of Spanish origin has been widely used in New Zealand plant breeding (Stewart, 2006), but another possibility that has attracted comparatively little research to date is introgression of summer dormant germplasm of North African origin with material of European origin. Methods Plants of a New Zealand-bred perennial ryegrass cultivar “Grasslands Samson”, a summer dormant Australian cultivar “Medea” developed in the 1960’s from germplasm of Mediterranean origin (Silsbury, 1961), and the F1 and F2 progenies of the two parents were compared during summer 2010-11 in a glasshouse study at Palmerston North, New Zealand. The experiment compared rooting behavior and herbage yield of the two cultivars and studied the pattern of inheritance of those traits to F1 and F2 progeny. Plants grown in 100 cm lengths of soil-filled PVC pipes were initially bottom-watered in 200 liter drums and then drought was imposed by gradually lowering the water table until plants survived on water retained in the soil profile. At a concluding destructive harvest, herbage yield (DW) and tiller number (TN) were recorded, while total root mass (Rt), coarse root mass (Rc) fine root mass (Rf) and gravimetric soil moisture % (SMC) were all measured for three soil depths (0-30, 30-60 and below 60 cm). From these data root:shoot ratio (R:S), deep root (below 30 cm): shoot ratio (DR:S), an index of deep rooting (% total root below 30 cm, IDR), and DW/(0.2 – SMC) as an index of efficient water use (IEWU) were derived. Results and Discussion Medea exhibited deep rooting compared to Grasslands Samson indicated by higher R:S, DR:S and IDR, that had never been studied since its release in Australia. However, it had lower IWU, 83% lower DW and 87% lower TN than Grasslands Samson – a characteristic of Mediterranean origin pasture species. On the question of introgressing root traits of Medea to Grasslands Samson: in the F1 generation, some plants surpassed Medea for some root traits (eg DR:S and IDR), while F2 plants were similar to Grasslands Samson parents, However, within Grasslands Samson itself some plants showed high IEWU. Conclusion Introgression of Medea genes into Grasslands Samson will not be straight forward. However, direct selection for maintenance of growth under moderate water deficit with reduced soil moisture extraction per unit DW is an immediate option for improving drought tolerance in perennial ryegrass, providing the trait proves sufficiently heritable. Stewart AV (2006) Genetic origins of perennial ryegrass (Lolium perenne) for New Zealand Pastures. Pp11-20 In: Breeding for success: diversity in action, (ed, CF. Mercer) Proceedings of the 13th Australasian Plant Breeding Conference, Christchurch, NZ. Silsbury JH (1961) A study of dormancy, survival and other characteristics in Lolium perenne L. at Adelaide, SA. Aust. J. Ag. Res.12:1-9.
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    (2016-09-04) Chen GX; McLean D; van den Berg L; 't Mannetje A; Pearce N; Kromhout H; D'Souza W; McConnell M; Douwes J
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    Green kiwifruit: effects on plasma lipids and APOE interactions
    (2012-05-28) Gammon CS; Kruger R; Minihane AM; Conlon CA; von Hurst PR; Stonehouse W
    Background Diet is a crucial element in the reduction of risk of cardiovascular disease (CVD). Furthermore, response to dietary change may be influenced by genotype. Kiwifruit are a good source of several dietary components shown to improve dyslipidaemia and lower CVD incidence such as soluble fibre and some vitamins and phytochemicals. Objective To investigate the effect of consuming two green kiwifruit daily in conjunction with a healthy diet on plasma lipids and examine response according to apolipoprotein E (APOE) genotype in hypercholesterolaemic men. Design Eighty-five hypercholesterolaemic men (low-density lipoprotein cholesterol (LDL-C) >3.0 mmol/L and triglycerides (TG) <3 mmol/L) completed an eight week randomised controlled cross-over study, after undergoing a four week healthy diet phase. The study consisted of two 4-week treatment sequences of 2 green kiwifruit/day plus healthy diet (intervention) or healthy diet alone (control). Fasting blood samples were taken at baseline, 4 and 8 weeks for the measurement of plasma lipids (total cholesterol (TC), LDL-C, TG, high-density lipoprotein cholesterol (HDL-C)), serum apolipoproteins A1 and B (apoA1 and apoB). Outcomes After the kiwifruit intervention plasma HDL-C concentrations were significantly higher (mean difference 0.04 [95% CI: 0.01, 0.07] mmol/L [P=0.004]) and the TC/HDL ratio was significantly lower (0.15 [-0.24, -0.05] mmol/L [P=0.002]), compared to control. In carriers of APOE4 allele TG concentrations were significantly lower (0.18 [-0.34, -0.02] mmol/L [P=0.03]) after the kiwifruit intervention compared to control. There were no significant differences between the two treatments for plasma TC, TG, LDL-C and serum apoA1 or apoB. Conclusion The small but significant increase in HDL-C and decrease in TC/HDL ratio and TG (in APOE4 carriers) suggests that the regular inclusion of green kiwifruit as part of a healthy diet may be beneficial in improving the lipid profiles of men with high cholesterol. Source of Funding: ZESPRI® International Trial No: ACTRN12610000213044