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- ItemEnvironmental drivers of antimicrobial resistance – cadmium contamination & antibiotic resistance in soil samples from a rural airstrip.(2023-12-05) Heydari A; Kim N; Biggs P; Horswell J; Gielen G; Siggins A; Bromhead C; Palmer BEnvironmental contamination with both inorganic and organic compounds is a growing problem globally. In this study we investigated links between heavy metal contamination of soil and selection for antibiotic resistance in soil bacteria. Soil samples taken at 10 m intervals along the length of a 70 m transect of a rural airstrip used for aerial topdressing located in Belmont Regional Park near Wellington were analysed for heavy metal content and resistance profiles of heterotrophic bacteria cultured were characterised. A gradient of cadmium contamination (a known contaminant of superphosphate fertiliser) ranging from 1.14 to 7.20 mg kg-1 of dry soil was detected in the samples. Total bacterial counts were significantly reduced at the most heavily contaminated subsites, with >60% of isolates resistant to 0.01 mM CdCl2. The ratio of antibiotic resistant isolates to total CFU was significantly higher at the most contaminated compared to the least contaminated subsite for five common antibiotics. Metagenomic analysis of total DNA from three subsites showed significantly different profiles at all taxonomic levels. This suggests environmental contamination with heavy metals may be a significant and under-appreciated driver of selection for antimicrobial resistance.
- ItemPrevalence of liver fluke on West Coast farms of the South Island of New Zealand sampled in the autumn and spring of consecutive lactations(2021-07-19) Dowling A; Pomroy W; Howe L; Scott I; Lawrence KThe aim of this study was to determine the occurrence of Fasciola hepatica infection in dairy cows in this West Coast of the South Island using an ELISA of bulk milk samples (n=430) collected on one of two occasions during March (autumn) 2017 and again in October (spring). All samples were analysed using the IDEXX Fasciolosis Verification kit which estimates the infection level in the herd in 4 categories; >50% infestation (strong); 20-50% infestation (medium); <20% infestation (low); no infection. A subset (n=99) were tested twice with a one week interval to determine repeatability. A short survey was also posted to each supplier with 157 completed. Of the 430 farms tested 133 (31%) were negative, 49 (11%) had a low infestation, 62 (14%) had a medium infestation and 186 (43%) had a strong infestation. GIS mapping of the farm locations indicated geographic grouping of farms with more severe fluke infestations. The 99 samples tested twice substantially agreed (Kappa = 0.7). Farms tested in both autumn and spring (n= 369) moderately agreed (Kappa 0.43) with an overall decrease in the spring. From the survey 85% of farmers were aware of liver fluke on their farm during the last 5 years and 70% treated their cows with a flukicide during the dry period (winter) including 92% of the farms that tested negative. This study indicates fasciolosis is common in this region with a disturbing number with a high prevalence in their herds. It also showed a decrease from autumn to following spring levels.
- ItemAcceptability 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
- ItemExploring consumer and wine expert views towards verjuice: a grape-based product made from a viticultural waste(2022-09-20) Dupas de Matos A; Maggs R; Hort J
- ItemEvaluating service user-led teaching in clinical psychology training(2023-01-13) Taylor J; Gordon SE
- ItemA genetic approach to identify amino acids in Gcn1 required for Gcn2 activation(2022-09-08) Schiemann A; Gottfried S; Sattlegger EThe 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.
- ItemWhy 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, RFCompared 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]
- ItemSensitivity to Volcanic Field Boundary(2016-04-17) Whitehead M; Bebbington M; Cronin S; Moufti MR; Lindsay JVolcanic 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.
- ItemTaiepa Tiketike - supporting Parihaka’s energy transition through a research partnership(2016-07-06) Curd J; Murray PE; Hohaia T
- ItemExploring 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 HSExploring 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: shmalik25@hotmail.com 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.
