91,047 results

  • Hypoxia-Activated Prodrugs: Substituent Effects on the Properties of Nitro seco-1,2,9,9a-Tetrahydrocyclopropa[c]benz[e]indol-4-one (nitroCBI) Prodrugs of DNA Minor Groove Alkylating Agents

    Tercel, Moana; Atwell, Graham; Yang, S; Stevenson, Ralph; Botting, KJ; Boyd, Maruta; Smith, E; Anderson, Robert; Denny, William; Wilson, William; Pruijn, Frederik (2009)

    Journal article
    The University of Auckland Library

    Nitrochloromethylbenzindolines (nitroCBIs) are a new class of hypoxia-activated prodrugs for antitumor therapy. The recently reported prototypes undergo hypoxia-selective metabolism to form potent DNA minor groove alkylating agents and are selectively toxic to some but not all hypoxic tumor cell lines. Here we report a series of 31 analogues that bear an extra electron-withdrawing substituent that serves to raise the one-electron reduction potential of the nitroCBI. We identify a subset of compounds, those with a basic side chain and sulfonamide or carboxamide substituent, that have consistently high hypoxic selectivity. The best of these, with a 7-sulfonamide substituent, displays hypoxic cytotoxicity ratios of 275 and 330 in Skov3 and HT29 human tumor cell lines, respectively. This compound (28) is efficiently and selectively metabolized to the corresponding aminoCBI, is selectively cytotoxic under hypoxia in all 11 cell lines examined, and demonstrates activity against hypoxic tumor cells in a human tumor xenograft in vivo.

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  • Preparation and antitumour properties of the enantiomers of a hypoxia-selective nitro analogue of the duocarmycins.

    Tercel, Moana; Lee, Ho; Yang, S; Liyanage, HD; Mehta, Sunali; Boyd, PD; Jaiswal, Jagdish; Tan, KL; Pruijn, Frederik (2011-10-04)

    Journal article
    The University of Auckland Library

    Racemic 2-{[1-(chloromethyl)-5-nitro-3-{5-[2-(dimethylamino)ethoxy]indol-2-carbonyl}-1,2-dihydro-3H-benzo[e]indol-7-yl]sulfonyl}aminoethyl dihydrogen phosphate, a synthetic nitro derivative of the duocarmycins, is a hypoxia-selective prodrug active against radiation-resistant tumour cells at nontoxic doses in mice. An intermediate in the synthesis of this prodrug was resolved by chiral HPLC and the absolute configuration assigned by X-ray crystallography. The intermediate was used to prepare the prodrug's enantiomers, and also the enantiomers of the active nitro and amino metabolites. In vitro analysis in the human cervical carcinoma cell line SiHa showed that both nitro enantiomers are hypoxia-selective cytotoxins, but the "natural" S enantiomer is at least 20-fold more potent. Examination of extracellular amino metabolite concentrations demonstrated no enantioselectivity in the hypoxia-selective reduction of nitro to amino. Low levels of amino derivative were also found in aerobic cell suspensions, sufficient to account for the observed oxic toxicity of the nitro form. At an equimolar dose in SiHa-tumour bearing animals, the (-)-R enantiomer of the prodrug was inactive, while the (+)-S enantiomer caused significantly more hypoxic tumour cell kill than the racemate. At this dose, the combination of (+)-S-prodrug and radiation eliminated detectable colony-forming cells in four out of five treated tumour-bearing animals.

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  • Working with and for communities: A collaborative study of harmony and conflict in well-functioning, acculturating families

    Stuart, Jaime; Ward, C; Jose, PE; Narayanan, P (2010)

    Journal article
    The University of Auckland Library

    The present research was conducted by the Centre for Applied Cross-cultural Research (CACR) in collaboration with the New Zealand Federation of Ethnic Councils (NZFEC) following a needs assessment of research priorities in the ethnic communities. Thirty-nine parents and adolescents from Asian, Middle Eastern and African backgrounds were interviewed about their experiences in New Zealand. The interviews were then analysed and organised into themes in line with a grounded theory approach. Two major themes emerged: (1) Normative Issues for Parents and Children and (2) Migration and Acculturation Issues, each of these with several sub-themes. Findings revealed that parents and adolescents differed in their expectations across a number of important domains (e.g., privacy, trust, and relationships) and that intergenerational conflict, which arises from normal developmental processes, may be exacerbated by the acculturation process. The research offers important insights about families in cultural transition to immigrant communities and policy makers; it also advances acculturation theory through its focus on the family as a unit and its examination of both harmony and conflict in acculturating families.

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  • The predictors of ethno-cultural identity conflict among South Asian immigrant youth in New Zealand

    Stuart, Jaime; Ward, C (2011)

    Journal article
    The University of Auckland Library

    The study tested a predictive model of ethno-cultural identity conflict (EIC) in a sample of 262 first-generation South Asian youth (aged 16-26, M = 19.4) in New Zealand. Hierarchical multiple regression was used to investigate the influence of: 1) attachment styles (preoccupied, dismissive, secure, and fearful); 2) family relations (intergenerational conflict and family cohesion); 3) ethnic (belonging, centrality, and exploration) and national identities; and 4) interactions between the components of ethnic and national identity. Controlling for demographic factors, results indicated that a preoccupied attachment style and experiences of acculturative intergenerational conflict exacerbated EIC, whereas family cohesion, ethnic identity centrality, and ethnic group belonging protected against EIC. It was also found that national identity moderated the effects of ethnic identity on EIC. Overall, these findings suggest positive self-regard, family cohesion, and integrated achieved identities should be promoted for immigrant youth.

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  • A Question of Balance: Exploring the Acculturation, Integration and Adaptation of Muslim Immigrant Youth

    Stuart, Jaime; Ward, C (2011)

    Journal article
    The University of Auckland Library

    The paper addresses criticisms of contemporary acculturation research by adopting a mixed method approach (open-ended survey responses, interviews, focus groups and projective techniques) to the study of the acculturation experiences of Muslim youth in New Zealand. The research explores: 1) the meaning, definition and achievement of success; 2) the process of negotiating multiple social identities; and 3) the graphic representation of identity. Thematic analysis indicated that young Muslims aspire to achieve success in personal, social, material and religious domains and that they seek to balance potentially competing demands from family, friends, the Muslim community and the wider society. At the same time they aspire to balance multiple identities, retaining religious and cultural elements in the definition of self while endeavoring to integrate into the wider society. The process of achieving this balance is characterized by three strategies: alternating orientations, blending orientations and minimizing differences. The findings are discussed in relation to advancing our understanding of integration as an acculturation option, and the community-based policy implications for multicultural societies are considered.

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  • What indicators are measured by tools designed to address palliative care competence among 'generalist' palliative care providers? a critical literature review

    Frey, Rosemary; Gott, Caryl; Banfield, R (2011)

    Journal article
    The University of Auckland Library

    Background: There is growing evidence that generalists may lack skills and knowledge in palliative care provision. This has led to consideration of what the core competencies for palliative care provision among generalists should be. Aim: The objective of this review was to present the best available evidence related to indicators of competence in palliative care provision. Method: A systematic review of both qualitative and quantitative literature was undertaken. Medline, Medline in Progress, PubMed and CINAHL databases with additional hand searches of Journal of Palliative Care, Palliative Medicine, and the International Journal of Palliative Nursing were undertaken for the period 1990???2010. Hawker et al.???s checklist was utilized to select and assess data. Results: Nineteen of the 1361 articles met the inclusion criteria. The reviewed articles suggest a number of indicators of palliative care competence including: medical knowledge/skills, perceptions of knowledge/ skills, confidence in palliative care skills, attitudes/opinions towards palliative care, and experience in palliative care delivery. None of the reviewed research provided definitive evidence as to which indicators best reflect competency to practice. Conclusion: Multiple approaches, combined in a strategy of triangulation, must be incorporated in any appraisal in order to successfully measure palliative care competence.

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  • Hydrodynamic theory of rising foam

    Stevenson, P (2007)

    Journal article
    The University of Auckland Library

    There is a large body of literature that tries to model flotation based on froth properties with little or no experimental verification of the underlying features. These models adopt the so called channel-dominated theory of foam drainage. There is no experimental evidence to support this foam drainage theory. Instead the new, simple and experimentally validated foam drainage equation of Stevenson (2006a) [Stevenson, P. 2006a. Dimensional analysis of foam drainage. Chem. Eng. Sci. 61, 4503???4510] has been extended to describe the liquid flux and liquid profile in columns of pneumatic froth. The condition for the maximum value of gas rate for froth stability has been described and this shows that there is a maximum volumetric liquid fraction that a foam can exhibit. It is shown that the numerical calculations of liquid profile of Neethling et al. (2003a,b) [Neethling, S.J., Lee, H.T., Cilliers, J.J. 2003a. The recovery of liquid from flowing foams. J. Phys.: Cond. Matter 15, 1563???1576; Neethling, S.J., Lee, H.T., Cilliers, J.J. 2003b. Simple relationships for predicting the recovery of liquid from flowing foams and froths. Miner. Eng. 16, 1123???1130] are incorrect, and this may mean that all of their later simulations of the flotation process are similarly deficient. Instead a simple and accessible method of calculated liquid fraction profiles, both with and without added washwater is shown. In addition, a model for the effect of surface and internal bubble coalescence on the hydrodynamic condition of the froth is presented. It is recognised that the gas???liquid systems considered in the current work are dissimilar to practical mineralised flotation froths and these differences are discussed.

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  • Synthesis and structure-activity relationships for 2,4-dinitrobenzamide-5-mustards as prodrugs for the E. coli nitroreductase (NTR) in gene therapy

    Atwell, Graham; Yang, SJ; Hogg, Alison; Pruijn, Frederik; Patterson, Adam; Wilson, William; Denny, William (2007)

    Journal article
    The University of Auckland Library

    A series of 2,4-dinitrobenzamide mustards were prepared from 5-chloro-2,4-dinitrobenzoic acid or the corresponding 5-dimesylate mustard as potential prodrugs for gene-directed enzyme prodrug therapy (GDEPT) with the E. coli nfsB nitroreductase (NTR). The compounds, including 32 new examples, were evaluated in four pairs of NTR+ve/-ve cell lines for selective cytotoxicity (IC50 and IC50 ratios), in multicellular layer (MCL) cultures for bystander effects, and for in vivo activity against tumors grown from stably NTR transfected EMT6 and WiDr cells in nude mice. Multivariate regression analysis of the IC50 results was undertaken using a partial least-squares projection to latent structures model. In NTR-ve lines, cytotoxicity correlated positively with logP, negatively with hydrogen bond acceptors (HA) and donors (HD) in the amide side chain, and positively with the reactivity of the less-reactive leaving group of the mustard function, likely reflecting toxicity due to DNA monoadducts. Potency and selectivity for NTR+ve lines was increased by logP and HD, decreased by HA, and was positively correlated with the leaving group efficiency of the more-reactive group, likely reflecting DNA crosslinking. NTR selectivity was greatest for asymmetric chloro/mesylate and bromo/mesylate mustards. Bystander effects in the MCL assay also correlated positively with logP and negatively with leaving group reactivity, presumably reflecting the transcellular diffusion/reaction properties of the activated metabolites. A total of 18 of 22 mustards showed equal or greater bystander efficiencies in MCLs than the aziridinylbenzamide CB 1954, which is currently in clinical trial for NTR-GDEPT. The dibromo and bromomesylate mustards were surprisingly well tolerated in mice. High MTD/IC50 (NTR+ve) ratios translated into curative activity of several compounds against NTR+ve tumors. A bromomesylate mustard showed superior activity against WiDr tumors grown from 1:9 mixtures of NTR+ve and NTR-ve cells, indicating a strong bystander effect in vivo.

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  • 'One assessment doesn't serve all the purposes' or does it? New Zealand teachers describe assessment and feedback

    Irving, Stephen; Harris, LR; Peterson, Elizabeth (2011)

    Journal article
    The University of Auckland Library

    Within the Asia-Pacific community, the New Zealand Ministry of Education has been one of few educational authorities to adopt an Assessment for Learning (AfL) framework and actively promote formative uses of assessment. This paper reports the results of a qualitative study in which eleven New Zealand secondary teachers in two focus groups discussed their conceptions of assessment and feedback. These data were examined to see how teachers defined and understood assessment and feedback processes to identify how these conceptions related to AfL perspectives on assessment. Categorical analysis of these data found teachers identified three types of assessment (formative, classroom teacher???controlled summative and external summative) with three distinct purposes (improvement, reporting and compliance, irrelevance). Feedback was seen as being about learning, grades and marks, or behaviour and effort; these types served the same purposes as assessment with the addition of an encouragement purpose. This study showed that although these New Zealand teachers appeared committed to AfL, there was still disagreement amongst teachers as to what practices could be deemed formative and how to best implement these types of assessment. Additionally, even in this relatively low-stakes environment, they noted tension between improvement and accountability purposes for assessment.

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  • Visualizing ocular lens fluid dynamics using MRI: manipulation of steady state water content and water fluxes

    Vaghefi Rezaei, Seyed; Pontre, Beau; Jacobs, Marc; Donaldson, Paul (2011)

    Journal article
    The University of Auckland Library

    Studies using various MRI techniques have shown that a water-protein concentration gradient exists in the ocular lens. Because this concentration is higher in the core relative to the lens periphery, a gradient in refractive index is established in the lens. To investigate how the water-protein concentration profile is maintained, bovine lenses were incubated in different solutions, and changes in water-protein concentration ratio monitored using proton density weighted (PD-weighted) imaging in the absence and presence of heavy water (D(2)O). Lenses incubated in artificial aqueous humor (AAH) maintained the steady state water-protein concentration gradient, but incubating lenses in high extracellular potassium (KCl-AAH) or low temperature (Low T-AAH) caused a collapse of the gradient due to a rise in water content in the core of the lens. To visualize water fluxes, lenses were incubated in D(2)O, which acts as a contrast agent. Incubation in KCl-AAH and low T-AAH dramatically slowed the movement of D(2)O into the core but did not affect the movement of D(2)O into the outer cortex. D(2)O seemed to preferentially enter the lens cortex at the anterior and posterior poles before moving circumferentially toward the equatorial regions. This directionality of D(2)O influx into the lens cortex was abolished by incubating lenses in high KCl-AAH or low T-AAH, and resulted in homogenous influx of D(2)O into the outer cortex. Taken together, our results show that the water-protein concentration ratio is actively maintained in the core of the lens and that water fluxes preferentially enter the lens at the poles.

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  • Prediction of Tumour Tissue Diffusion Coefficients of Hypoxia-Activated Prodrugs from Physicochemical Parameters

    Pruijn, Frederik; Patel, Kashyap; Hay, Michael; Wilson, William; Hicks, Kevin (2008)

    Journal article
    The University of Auckland Library

    The therapeutic activity of anticancer agents depends critically on their ability to penetrate through tumour tissue to reach their target cells, a requirement that is especially important for hypoxia-activated prodrugs. Here we use multicellular layers (MCL) grown in vitro from HT29 colon carcinoma cells to measure tissue diffusion coefficients (Dmcl) of 67 structurally diverse benzotriazine di-N-oxides (analogues of the hypoxia-activated prodrug tirapazamine) plus four miscellaneous compounds.An algorithm was developed to predict Dmcl from physicochemical parameters (molecular weight, octanol/water partition coefficient at pH 7.4, number of hydrogen bond donors and acceptors); the fitted multivariate relationship had an explained variance (R2) of 0.907 and predictive power (Q2) of 0.879. Using a subset of nine compounds tested as a single cassette, the algorithm was shown to apply, with some adjustment of coefficients, to MCLs from three other tumour cell lines with differing cell packing densities (SiHa, HCT8-Ea, and HCT8-Ra). The demonstrated relationships provide tools for optimizing extravascular transport of anticancer agents during lead optimization.

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  • Effect of Bronchoalveolar Lavage-Directed Therapy on Pseudomonas aeruginosa Infection and Structural Lung Injury in Children With Cystic Fibrosis A Randomized Trial

    Wainwright, CE; Vidmar, S; Armstrong, DS; Byrnes, Catherine; Carlin, JB; Cheney, J; Cooper, PJ; Grimwood, K; Moodie, M; Robertson, CF; Tiddens, HA (2011-07-13)

    Journal article
    The University of Auckland Library

    Context Early pulmonary infection in children with cystic fibrosis leads to increased morbidity and mortality. Despite wide use of oropharyngeal cultures to identify pulmonary infection, concerns remain over their diagnostic accuracy. While bronchoalveolar lavage (BAL) is an alternative diagnostic tool, evidence for its clinical benefit is lacking.Objective To determine if BAL-directed therapy for pulmonary exacerbations during the first 5 years of life provides better outcomes than current standard practice relying on clinical features and oropharyngeal cultures.Design, Setting, and Participants The Australasian Cystic Fibrosis Bronchoalveolar Lavage (ACFBAL) randomized controlled trial, recruiting infants diagnosed with cystic fibrosis through newborn screening programs in 8 Australasian cystic fibrosis centers. Recruitment occurred between June 1, 1999, and April 30, 2005, with the study ending on December 31, 2009.Interventions BAL-directed (n=84) or standard (n=86) therapy until age 5 years. The BAL-directed therapy group underwent BAL before age 6 months when well, when hospitalized for pulmonary exacerbations, if Pseudomonas aeruginosa was detected in oropharyngeal specimens, and after P aeruginosa eradication therapy. Treatment was prescribed according to BAL or oropharyngeal culture results.Main Outcome Measures Primary outcomes at age 5 years were prevalence of P aeruginosa on BAL cultures and total cystic fibrosis computed tomography (CF-CT) score (as a percentage of the maximum score) on high-resolution chest CT scan.Results Of 267 infants diagnosed with cystic fibrosis following newborn screening, 170 were enrolled and randomized, and 157 completed the study. At age 5 years, 8 of 79 children (10%) in the BAL-directed therapy group and 9 of 76 (12%) in the standard therapy group had P aeruginosa in final BAL cultures (risk difference, -1.7% [95% confidence interval, -11.6% to 8.1%]; P=.73). Mean total CF-CT scores for the BAL-directed therapy and standard therapy groups were 3.0% and 2.8%, respectively (mean difference, 0.19% [95% confidence interval, -0.94% to 1.33%]; P=.74).Conclusion Among infants diagnosed with cystic fibrosis, BAL-directed therapy did not result in a lower prevalence of P aeruginosa infection or lower total CF-CT score when compared with standard therapy at age 5 years.

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  • Global map of the prevalence of symptoms of rhinoconjunctivitis in children: The International Study of Asthma and Allergies in Childhood Phase Three

    A??t-Khaled, N; Pearce, N; Anderson, HR; Ellwood, Philippa; Montefort, S; and the ISAAC Phase Three Study Group; Shah, J; Clayton, Tadd; Mitchell, Edwin; Stewart, AW; Asher, Monica Innes (2009)

    Journal article
    The University of Auckland Library

    Background: Phase One of the International Study of Asthma and Allergies in Childhood (ISAAC) measured the global patterns of prevalence and severity of symptoms of rhinoconjunctivitis in children in 1993???1997. Methods: International Study of Asthma and Allergies in Childhood Phase Three was a cross-sectional survey performed 5???10 years after Phase One using the same methodology. Phase Three covered all of the major regions of the world and involved 1 059 053 children of 2 age groups from 236 centres in 98 countries. Results: The average overall prevalence of current rhinoconjunctivitis symptoms was 14.6% for the 13- to 14-year old children (range 1.0???45%). Variation in the prevalence of severe rhinoconjunctivitis symptoms was observed between centres (range 0.0???5.1%) and regions (range 0.4% in western Europe to 2.3% in Africa), with the highest prevalence being observed mainly in the centres from middle and low income countries, particularly in Africa and Latin America. Co-morbidity with asthma and eczema varied from 1.6% in the Indian sub-continent to 4.7% in North America. For 6- to 7-year old children, the average prevalence of rhinoconjunctivitis symptoms was 8.5%, and large variations in symptom prevalence were also observed between regions, countries and centres. Conclusions: Wide global variations exist in the prevalence of current rhinoconjunctivitis symptoms, being higher in high vs low income countries, but the prevalence of severe symptoms was greater in less affluent countries. Co-morbidity with asthma is high particularly in Africa, North America and Oceania. This global map of symptom prevalence is of clinical importance for health professionals.

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  • Chronic Respiratory Symptoms and Diseases Among Indigenous Children

    Redding, GJ; Byrnes, Catherine (2009)

    Journal article
    The University of Auckland Library

    A review of the burden of respiratory disease affecting indigenous children worldwide with particular attention to Alaskan Aboriginal, American Native, Australian Aboriginal & New Zealand Maori. The article discusses the statistics, possible causes and management options for the spectrum of respiratory diseases seen in these groups.

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  • Experimental in-plane strength investigation of reinforced concrete masonry walls with openings

    Voon, Kok; Ingham, Jason (2008)

    Journal article
    The University of Auckland Library

    This paper presents test results of eight partially grout-filled perforated concrete masonry walls that were subjected to cyclic lateral loading. Test results obtained from this research indicated that the size of openings and the length of trimming reinforcement significantly affected the lateral strength of perforated masonry walls. It was shown that the current New Zealand nonspecific masonry design standard NZS 4229 unsafely overpredicts the strength capacity of concrete masonry walls with small openings, and an amendment is proposed to rectify this matter. It was also shown that NZS 4229 is increasingly conservative as the height of openings increased. Diagonal cracking patterns that formed during testing were observed to align well with the load paths by which lateral shear force was assumed to be transferred to the foundation when using strut-and-tie analysis. This observation supports the use of the strut-and-tie technique as a viable tool to evaluate the flexural strength of walls of this type.

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  • Design Expression for the In-plane Shear Strength of Reinforced Concrete Masonry

    Voon, Kok; Ingham, Jason (2007)

    Journal article
    The University of Auckland Library

    Aspects relating to codification of the in-plane shear strength of concrete masonry walls when subjected to seismic loading are presented in this paper. Particular emphasis is placed on a model that is capable of representing the interaction between flexural ductility and masonry shear strength to account for the reduction in shear strength as ductility level increases. The simple method proposed here allows the strength enhancement provided by axial compression load to be separated from the masonry component of shear strength and is considered to result from strut action. In addition, minor modifications are made to facilitate adoption of the method in the updated version of the New Zealand masonry design standard, NZS 4230:2004. Prediction of shear strength from NZS 4230:2004 and alternative methods are compared with results from a wide range of masonry walls tests failing in shear. It was established that the shear equation in the former version of the New Zealand masonry standard (NZS 4230:1990) was overly conservative in its prediction of masonry shear strength. The current National Earthquake Hazards Reduction Program (NEHRP) shear expression was found to be commendable, but it does not address masonry shear strength within plastic hinge regions, therefore limiting its use when designing masonry structures in seismic regions. Finally, the new shear equation implemented in NZS 4230:2004 was found to provide significantly improved shear strength prediction with respect to its predecessor, with accuracy close to that resulted from NEHRP.

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  • Experimental in-plane shear strength investigation of reinforced concrete masonry walls

    Voon, Kok; Ingham, Jason (2006)

    Journal article
    The University of Auckland Library

    This paper presents test results of ten single-story reinforced concrete masonry shear walls. Test results are summarized and compared with design formulae specified by the New Zealand masonry design standard NZS 4230:1990 and by the National Earthquake Hazards Reduction Program. It was determined that the test walls exhibited shear strength significantly exceeding the NZS 4230:1990 maximum permissible shear stress, confirming that NZS 4230:1990 was overly conservative in accounting for masonry shear strength. It was also confirmed from the test results that masonry shear strength increases with the magnitude of applied axial compressive stress and the amount of shear reinforcement, but that the shear strength decreases inversely in relation to an increase in wall aspect ratio. In addition, it was shown that the postcracking performance of shear dominated walls was substantially improved when uniformly distributing the shear reinforcement up the height of the walls.

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  • The impact of the method of consent on response rates in the ISAAC time trends study

    Ellwood, Philippa; Asher, Monica Innes; Stewart, Alistair; the ISAAC Phase Three Study Group (2010-08)

    Journal article
    The University of Auckland Library

    BACKGROUND: Centres in Phases One and Three of the International Study of Asthma and Allergies in Childhood (ISAAC) programme used the method of consent (passive or active) required by local ethics committees.METHODS: Retrospectively, relationships between achieved response rates and method of consent for 13 14 and 6-7-year-olds (adolescents and children, respectively), were examined between phases and between English and non-English language centres.RESULTS: Information was obtained for 113 of 115 centres for adolescents and 72/72 centres for children. Both age groups: most centres using passive consent achieved high response rates (>80% adolescents and >70% children). English language centres using active consent showed a larger decrease in response rate. Ado-lescents: seven centres changed from passive consent in Phase I to active consent in Phase III (median decrease of 13%), with five centres showing lower response rates (as low as 34%). Children: no centre changed consent method between phases. Centres using active consent had lower median response rates (lowest response rate 45%).CONCLUSION: The requirement for active consent for population school-based questionnaire studies can impact negatively on response rates, particularly English language centres, thus adversely affecting the validity of the data. Ethics committees need to consider this issue carefully.

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  • Translation of questions: the International Study of Asthma and Allergies in Childhood (ISAAC) experience.

    Ellwood, Philippa; Williams, H; A??t-Khaled, N; Bj??rkst??n, B; Robertson, CF; and the ISAAC Phase Three Study Group; Asher, MI; Stewart, AW; Clayton, Tadd (2009-09)

    Journal article
    The University of Auckland Library

    OBJECTIVE: To explore the consequences of translating the International Study of Asthma and Allergies in Childhood (ISAAC) English core questionnaires on asthma, rhinitis and eczema symptoms into other languages. DESIGN: ISAAC Phase III developed 49 language translations for adolescents and 42 for children following standardised guidelines, which included back-translating the questionnaires into English to check their accuracy and meaning. Language deviations were categorised and analysed with regard to influences on the reported symptom prevalence. RESULTS: Category 1 deviations for one or more questions were found in seven translations (14%) for adolescents and in three translations (7%) for children. Data for these questions were excluded from the worldwide analyses. Category 2 deviations were identified in the publications, and Category 3 deviations were ignored. CONCLUSIONS: Translations of questionnaires should follow a consistent protocol in global epidemiological research. Cultural norms need to be considered when evaluating back-translations into English, as disease labels are not available in every language, nor are they understood in the same way. Deviations from literal translations of English should be permitted if the intent of the original meaning is retained. A web-based tool of medical terminology would be useful for international research requiring the use of translations.

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  • Effect of the substrate hardness on particle morphology in high velocity thermal spray coatings

    Trompetter, William; Hyland, Margaret; McGrouther, D; Munroe, P; Markwitz, A (2006)

    Journal article
    The University of Auckland Library

    In this study, Ni-chrome alloy particles were thermally sprayed onto a variety of substrate materials using the high-velocity air fuel (HVAF) technique. Although the various substrate materials were sprayed using identical powder material and thermal spray conditions, the type and variation of splat morphologies were strongly dependent on the substrate material. Predominantly solid splats are observed penetrating deeply into softer substrates, such as aluminum, whereas molten splats were observed on harder substrates, which resisted particle penetration. The observed correlation between molten splats and substrate hardness could be due a dependency of deposition efficiencies of solid and molten splats on the substrate material. However, it was found that conversion of particle kinetic energy into plastic deformation and heat, dependent on substrate hardness, can make a significant contribution towards explaining the observed behavior.

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