89,490 results

  • Connexin hemichannel blockade improves outcomes in a model of fetal ischemia

    Davidson, Joanne; Green, Colin; Nicholson, Louise; OCarroll, Simon; Fraser, Mhoyra; Bennet, Laura; Gunn, Alistair (2012)

    Journal article
    The University of Auckland Library

    Objective: Connexin hemichannels can open during ischemia, resulting in loss of membrane potential, calcium influx, and release of glutamate. In this study, we tested the hypothesis that opening of hemichannels after cerebral ischemia may contribute to delayed evolution of injury. Methods: We infused a mimetic peptide that blocks connexin 43 hemichannels into the lateral ventricle of chronically instrumented fetal sheep in utero at 128 ?? 1 days gestation (term is 147 days), starting 90 minutes after 30 minutes of severe ischemia induced by reversible bilateral carotid artery occlusion, for either 1 or 25 hours. Sheep were killed 7 days later. Results: Peptide infusion was associated with a graded improvement in recovery of electroencephalographic power after 7 days recovery, from ???13 ?? 1.9dB (n = 7) after ischemia???vehicle to ???9 ?? 1.6dB (n = 7) after ischemia???short infusion and ???5 ?? 1.6dB after ischemia???long infusion (n = 6, p < 0.05). Peptide infusion was associated with reduced seizure activity after ischemia, less frequent status epilepticus (p < 0.05), and earlier return of sleep state cycling (p < 0.05). Ischemia???long infusion (but not ischemia???short infusion) was associated with improved survival of oligodendrocytes in intragyral and periventricular white matter (p < 0.05) and increased brain weight (p < 0.05). Ischemia???long infusion was associated with an intermediate estimate of surviving neurons in the parasagittal cortex of 2.9 ?? 0.8 ?? 106, in comparison to sham control (4.3 ?? 0.9 ?? 106) or ischemia???vehicle (1.5 ?? 0.4 ?? 106; p < 0.05 vs sham control). Interpretation: These data support the hypothesis that opening of connexin hemichannels is a significant mediator of postischemic white and gray matter dysfunction and injury.

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  • Propensities to Engage in and Punish Corrupt Behavior: Experimental Evidence from Australia, India, Indonesia and Singapore.

    Cameron, LA; Chaudhuri, Ananish; Erkal, N; Gangadharan, L (2009)

    Journal article
    The University of Auckland Library

    This paper examines cultural differences in individual decision-making in a corruption game. We define culture as an individual's accumulated experience, shaped by the social, institutional, and economic aspects of the environment in which the individual lives. Based on experiments run in Australia (Melbourne), India (Delhi), Indonesia (Jakarta) and Singapore, we find that there is a greater variation in the propensities to punish corrupt behavior than in the propensities to engage in corrupt behavior across cultures. Consistent with the existing corruption indices, the subjects in India exhibit a higher tolerance of corruption than the subjects in Australia. However, the subjects in Singapore have a higher tolerance and the subjects in Indonesia have much lower tolerance of corruption than expected. We conjecture that this is due to the nature of the recent institutional changes in these two countries. We also vary our experimental design to examine the impact of the perceived cost of bribery and find that the results are culture-specific.

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  • Understanding Willingness-to-Pay Formation of Repeat Bidders in Sequential Online Auctions

    Goes, P; Karuga, G; Tripathi, Arvind (2010)

    Journal article
    The University of Auckland Library

    A growing number of vendors are using a sequence of online auctions to sell large inventories of identical items. Although bidding strategies and bidder behavior in single auctions have been extensively studied, limited research exists on bidding in sequential auctions. We seek to explain how bidders in such an environment learn from the information, and form and update their willingness to pay (WTP). Using a large data set from an online auction retailer, we analyze the evolution of the bidders' WTP as well as the effect of auction design on bidders' WTP in sequential auctions. We see our study in the context of a longitudinal field experiment, in which we were able to track actions of repeat bidders over an extended period of time. Our results show that bidders' WTP in sequential auctions can be explained from their demand characteristics, their participation experience in previous auctions, outcomes in previous auctions, and auction design parameters. We also observe, characterize, and measure what we call a modified demand reduction effect exhibited across different auctions, over time, by multiunit demand bidders. Our findings are important to enable better auction mechanism design, and more sophisticated bidding tools that explore the rich information environment of sequential auctions.

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  • Norske Skog Improves Global Profitability Using Operations Research

    Everett, G; Philpott, Andrew; Vatn, K; Gjessing, R (2010)

    Journal article
    The University of Auckland Library

    Many businesses are currently uncertain of how the economic recession will affect demand for their services and products. For global papermaker Norske Skog, this is a familiar situation. Over the past decade, the company has experienced declining demand for its products as electronic media have replaced newsprint publications. As it struggles to survive, the company has been forced to make some difficult decisions, including closing paper production lines and entire mills. Operations research (OR) models have become a vital part of Norske Skog???s decision-making process, helping the company to significantly reduce costs and enabling senior managers to make difficult choices with confidence that their solutions are the best possible. The tactical use of OR models has provided solutions that enable Norske Skog to save US$8 million and US$10 million annually in Australasia and Europe, respectively. In 2008, the Norske Skog Board used a model to make a strategic decision to close two paper mills and a paper machine, saving the company US$100 million annually, compared with the status quo. These savings are equivalent to 3 percent of the company???s revenue.

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  • Of Spies, a Ship and a Videotape - Stop, Pause, Play, Rewind, Play: Inspection and use of the Videotape of the Rainbow Warrior Court Proceedings

    Tobin, Audrey (2008)

    Journal article
    The University of Auckland Library

    In New Zealand access to court files in criminal proceedings is at the discretion of a judge or registrar. This article traces the way the rationale for the discretion changed over the last twenty years as the two French agents involved in the Rainbow Warrior bombing sought to prevent access to the court file containing the videotape showing their guilty pleas to a charge of manslaughter. Open justice and freedom of expression do not directly govern the exercise of the discretion but they are an essential part of the balancing process now undertaken by the Courts when requests are made to access Court files.

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  • Unstable Building: Virtual Environments and Real Relevance

    Mc Meel, Dermott; Cockeram, J (2010)

    Journal article
    The University of Auckland Library

    Design is often romanticised as a solitary pursuit and the pedagogical framework within educational environments often cements this perception with the demand for individual student assessment. In popular journals the architect as artist is celebrated for singular vision and the tenacity to realise that vision. However, in practice as designs evolve into construction the process becomes decidedly collaborative, with engineers, interior designers and contractors contributing unique parts as the design evolves to accommodate revision and change. This paper will bring evidence to bear that suggests the value in using Virtual Environments (VE???s) is in their potential to facilitate collaboration, and not just in the popularised phenomenon of 3D or 4D model creation. We use design theorist Brian Lawson???s design problem/solution mapping of analysis, appraisal and synthesis as a framework to scrutinize design and construction in the VE Second Life. Within this framework we draw on philosophical reflects by Ludwig Wittgenstein and appropriate cultural theory from Richard Sennett, Mary Douglas and Lewis Hyde. Which provides a theoretical underpinning to our observational evidence that suggests VE???s contribute to Lawson???s constituents of analysis and appraisal as well as 3D synthesis. Striations, breakdown and friction are brought to centre stage during collaboration in this virtual environment; we argue these facets to collaboration have value for emergent designers as important source of opportunity and innovation. Observations challenge attempts by popular collaborative software to expunge these clashes and conflicts from the design and construction process. VE???s bring breakdown and conflict into focus, sensitising emergent practitioners to it???s inherent potential for both problematic conflict and creative opportunity. Findings suggest that VE???s have considerable influence not only for verisimilitude but for simulating the fluid or ???unstable??? design and construction process and promoting the development of skills that Lawson contents are fundamental to the designer and which cultural theorist Richard Sennett posits are critical to the notion of craft.

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  • Towards a pre-service technology teacher education resource for New Zealand

    Forret, M; Fox-Turnbull, W; Granshaw, B; Harwood, C; Miller, A; O'Sullivan, G; Patterson, Moira (2011-12-04)

    Journal article
    The University of Auckland Library

    The Pre-service Technology Teacher Education Resource (PTTER) was developed as a cross-institutional resource to support the development of initial technology teacher education programmes in New Zealand. The PTTER was developed through collabortion involving representatives from each of the six New Zealand university teacher education providers, Massey University, University of Auckland, University of Canterbury, University of Otago, Victoria University and University of Waikato, working with the National Technology Professional Development Manager. The framework for PTTER is built on four key elements considered to be essential to the education of technology teachers. The four elements are: philosophy of technology, rationale for technology education, technology in the New Zealand curriculum, and teaching technology. The PTTER is a web-based resource aimed at assisting technology teacher educators in the development of their teacher education programmes. The framework is a statement of shared philosophy, purpose and intent and is located on the Techlink website (www.techlink.org.nz). PTTER contains a range of teaching resources and strategies located within an overall framework for initial technology teacher education programmes. This paper describes the rationale for the PTTER framework, the process through which it was developed, explanation of each of the framework???s elements, and concludes with discussion of the framework???s implementation and future development.

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  • Sustaining cooperation in laboratory public goods experiments: A selective survey of the literature

    Chaudhuri, Ananish (2011)

    Journal article
    The University of Auckland Library

    I survey the literature post Ledyard (Handbook of Experimental Economics, ed. by J. Kagel, A. Roth, Chap. 2, Princeton, Princeton University Press, 1995) on three related issues in linear public goods experiments: (1) conditional cooperation; (2) the role of costly monetary punishments in sustaining cooperation and (3) the sustenance of cooperation via means other than such punishments. Many participants in laboratory public goods experiments are ???conditional cooperators??? whose contributions to the public good are positively correlated with their beliefs about the average group contribution. Conditional cooperators are often able to sustain high contributions to the public good through costly monetary punishment of free-riders but also by other mechanisms such as expressions of disapproval, advice giving and assortative matching.

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  • Detailed analysis of inflammatory and neuromodulatory cytokine secretion from human NT2 astrocytes using multiplex bead array

    Burkert, K; Moodley, K; Angel, Catherine; Brooks, Anna; Graham, Euan (2012)

    Journal article
    The University of Auckland Library

    Astrocytes are a very important cell type in the brain fulfilling roles in both neuroimmunology and neurotransmission. We have conducted the most comprehensive analysis of secreted cytokines conducted to date (astrocytes of any source) to determine whether astrocytes derived from the human Ntera2 (NT2) cell-line are a good model of human primary astrocytes. We have compared the secretion of cytokines from NT2 astrocytes with those produced in astrocyte enriched human brain cultures and additional cytokines implicated in brain injury or known to be expressed in the human brain. The concentration of cytokines was measured in astrocyte conditioned media using multiplex bead array (MBA), where 18 cytokines were measured simultaneously. Resting NT2 astrocytes produced low levels (???1-30pg/ml) of MIP1??, IL-6 and GM-CSF and higher levels of MCP-1, IP-10 and IL-8 (1-11ng/ml) under non-inflammatory conditions. All of these in addition to IL-1??, TNF??, and IL-13, were increased by pro-inflammatory activation (TNF?? or IL-1?? stimulation). In contrast, IL-2, IL-4, IL-5, IL-7, IL-10, IL-12, LT??, and IFN?? were not detected in astrocyte conditioned media under any of the culture conditions tested. NT2 astrocytes were unresponsive to IL-2 and the adenyl cyclase agonist, forskolin. Interestingly, IFN?? stimulation selectively increased IP-10 secretion only. As astrocytes stimulated with IL-1?? or TNF?? produced several chemokines in the ng/ml range, we next assessed the chemoattractant properties of these cells. Conditioned media from TNF??-stimulated astrocytes significantly chemoattracted leucocytes from human blood. This study provides the most comprehensive analysis of cytokine production by human astrocytes thus far, and shows that NT2 astrocytes are highly responsive to pro-inflammatory mediators including TNF?? and IL-1??, producing cytokines and chemokines capable of attracting leucocytes from human blood. We conclude that in the absence of adult human primary astrocytes that NT2-astrocytes may provide a valuable alternative to study the immunological behaviour of human astrocytes.

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  • Compulsory community mental health treatment: Literature review

    O'Brien, Anthony; McKenna, Brian; Kydd, Robert (2009-09)

    Journal article
    The University of Auckland Library

    Following their introduction in the United States in the 1970s various forms of compulsory treatment in the community have been introduced internationally. Compulsory treatment in the community involves a statutory framework that mandates enforceable treatment in a community setting. Such frameworks can be categorized as preventative, least restrictive, or as having both preventative and least restrictive features. Research falls into two categories; descriptive, naturalistic studies and controlled and uncontrolled comparative studies. The research has produced equivocal results, and presents numerous methodological challenges. Where programmes have demonstrated improved outcomes debate continues as to whether these Outcomes are associated with legal compulsion or enhanced service provision. Service user, family and clinician perspectives demonstrate a divergence of views within and across groups, with clinicians more strongly in support than service users. The issue of compulsory community treatment is an important one for nurses, who are often at the forefront of clinical service provision, in some cases in statutory roles. Critical reflection on the issue of compulsory community, treatment requires understanding of the limitations of empirical investigations and of the various ethical and social policy issues involved. There is a need for further research into compulsory community treatment and possible alternatives. (C) 2009 Elsevier Ltd. All rights reserved.

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  • Determinants of outcomes after head cooling for neonatal encephalopathy

    Wyatt, JS; Gluckman, Peter; Liu, PY; Azzopardi, Denis; Ballard, R; Edwards, AD; Ferriero, DM; Polin, RA; Robertson, CM; Thoresen, Marianne; Whitelaw, A; Gunn, Alistair (2007)

    Journal article
    The University of Auckland Library

    OBJECTIVE. The goal of this study was to evaluate the role of factors that may determine the efficacy of treatment with delayed head cooling and mild systemic hypothermia for neonatal encephalopathy. METHODS. A total of 218 term infants with moderate to severe neonatal encephalopathy plus abnormal amplitude-integrated electroencephalographic recordings, assigned randomly to head cooling for 72 hours, starting within 6 hours after birth (with the rectal temperature maintained at 34.5 ?? 0.5??C), or conventional care, were studied. Death or severe disability at 18 months of age was assessed in a multicenter, randomized, controlled study (the CoolCap trial). RESULTS. Treatment, lower encephalopathy grade, lower birth weight, greater amplitude-integrated electroencephalographic amplitude, absence of seizures, and higher Apgar score, but not gender or gestational age, were associated significantly with better outcomes. In a multivariate analysis, each of the individually predictive factors except for Apgar score remained predictive. There was a significant interaction between treatment and birth weight, categorized as ???25th or <25th percentile for term, such that larger infants showed a lower frequency of favorable outcomes in the control group but greater improvement with cooling. For larger infants, the number needed to treat was 3.8. Pyrexia (???38??C) in control infants was associated with adverse outcomes. Although there was a small correlation with birth weight, the adverse effect of greater birth weight in control infants remained significant after adjustment for pyrexia and severity of encephalopathy. CONCLUSIONS. Outcomes after hypothermic treatment were strongly influenced by the severity of neonatal encephalopathy. The protective effect of hypothermia was greater in larger infants.

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  • Therapeutic hypothermia changes the prognostic value of clinical evaluation of neonatal encephalopathy

    Gunn, Alistair; Wyatt, JS; Whitelaw, A; Barks, J; Azzopardi, D; Ballard, R; Edwards, AD; Ferriero, DM; Gluckman, Peter; Polin, RA; Robertson, CM; Thoresen, M (2008-01)

    Journal article
    The University of Auckland Library

    Objective To evaluate whether therapeutic hypothermia alters the prognostic value of clinical grading of neonatal encephalopathy.Study design This study was a secondary analysis of a multicenter study of 234 term infants with neonatal encephalopathy randomized to head cooling for 72 hours starting within 6 hours of birth, with rectal temperature maintained at 34.5 degrees C +/- 0.5 degrees C, followed by re-warming for 4 hours, or standard care at 37.0 degrees C +/- 0.5 degrees C. Severity of encephalopathy was measured pre-randomization and on day 4, after re-warming, in 177 infants; 31 infants died before day 4, and data were missing for 10 infants. The primary outcome wits death or severe disability at 18 months of age.Results Milder pre-randomization encephalopathy, greater improvement in encephalopathy from randomization to day 4, and cooling were associated with favorable outcome in multivariate binary logistic regression. Hypothermia did not affect severity of encephalopathy at day 4, however, in infants with moderate encephalopathy at day 4, those treated with hypothermia had a significantly higher rate of favorable outcome (31/45 infants, 69%, P =.006) compared with standard care (12/33, 36%).Conclusion Infants with moderate encephalopathy on day 4 may have a more favorable prognosis after hypothermia treatment than expected after standard care.

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  • Common Law Actions on the Margin

    Tobin, Audrey (2008)

    Journal article
    The University of Auckland Library

    The boundary areas between illness and disease will always be difficult to draw. This paper considers two areas that have led to difficulty in the context of the accident compensation scheme: cases involving mental injury alone and cases of unplanned pregnancy. The author argues that in a comprehensive accident compensation scheme the definition of personal injury should take cognizance of developments in medical knowledge, and include mental injury. An unplanned pregnancy as a personal injury to the mother creates special difficulties, and indeed does some violence to the definitions in the legislation. The author suggests that a legislative amendment to clarify this is desirable.

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  • Food pyramids, keeping clean and sex talks: Pre-service teachers, experiences and perceptions of school health education.

    Sinkinson, Margaret; Hughes, Dianne (2008)

    Journal article
    The University of Auckland Library

    This paper reports findings from the first stage of an anticipated four-stage research project investigating the effectiveness of teacher education in health education. Prior to receiving any teacher education in health education, pre-service teachers (student teachers) were surveyed for their experiences of secondary school health education, and their beliefs about and attitudes toward the subject. Data were collected from questionnaire surveys (n=295) and focus group interviews (n=61). Results showed that student teachers had more exposure to school health education than had been assumed, and had more positive attitudes toward the subject area than indicated by other studies into school health education. Many reported having had sexuality education and drug and alcohol programmes, but these were commonly described in contexts of safety rules and risk avoidance behaviours. Participants had greater understanding of and more exposure to mental health education than had been predicted. Those aged 20 years and younger reported significantly greater exposure to a range of school health education topics than did those aged 21 - 30 years, or 30+ years. This difference is attributed to the younger participants receiving health education based on the Health and Physical Education in the New Zealand Curriculum, introduced into schools in 1999.

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  • Back to the future: Reoccurring issues and discourses in health education in New Zealand schools

    Sinkinson, Margaret (2011)

    Journal article
    The University of Auckland Library

    A key function of health education in New Zealand schools has always been to educate individuals to be responsible and accountable for their own health status. Educational, economic and political stances on what best constitutes effective health education however, shift over time. The outcome of these shifts is that a multiplicity of disciplines and theoretical frameworks has informed pedagogical practices in this subject area, and continue to do so. Psychology, sociology, philosophy and biological sciences are all visible in school health education syllabi. Currently a range of concepts and theories underpin the subject, ranging from critical theory and post structuralism to cognitive behavioural theory and behaviour change models. Although various disciplines, concepts and theories have fashioned the delivery and content of past and present school health education, none have proved particularly effective in moving it away from pervasive and enduring discourses of individualism. Examined in this article are socio-political influences on curriculum directions and discourses over the last century, including the part played by external bodies in determining health education subject matter and health behaviour emphases.

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  • Social deprivation and use of mental health legislation in New Zealand

    O'Brien, Anthony; Kydd, Robert; Frampton, C (2011-08-22)

    Journal article
    The University of Auckland Library

    BACKGROUND: Low socioeconomic status has consistently been associated with poorer health outcomes. Few studies have used ecological analysis to explore relationships between area measures of deprivation and use of mental health legislation. METHODS: We used an ecological design to explore associations between two area measures of relative deprivation and the two most commonly used sections of New Zealand mental health legislation. RESULTS: High levels of relative deprivation were positively correlated with use of both acute and long-term community care provisions of mental health legislation with the correlation with long-term care achieving significance (r = .518, p = .016). Low levels of relative deprivation showed negative correlations with use of both provisions. The correlation of -.493 between low levels of relative deprivation and acute care provisions was significant at p = .023. In stepwise regression, the proportion of the population aged 15-64 contributed to the model for section 11, but ethnicity contributed to neither model. CONCLUSION: Mental health legislation is used disproportionately in areas with high levels of relative deprivation. The results have implications for regional allocation of funding for mental health and social services to support community-based care. Further research is needed to explore other factors that may account for the regional variation.

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  • Use of Tasers on people with mental illness. A New Zealand database study

    O'Brien, Anthony; McKenna, Brian; Thom, KA; Diesfeld, K; Simpson, AIF (2010)

    Journal article
    The University of Auckland Library

    Abstract Background In 2006 -2007 New Zealand police deployed the Taser X26 electro-muscular incapacitation device for a twelve month trial across four police districts. Criteria for use of the Taser included "individuals in various states of mental health crisis". Aims To provide a descriptive analysis of the use of Tasers by the New Zealand police; to identify those incidents that involved people in mental health emergencies; and to compare this use with that which occurred in incidents of criminal arrest. Method Descriptive analysis of the police Tactical Operations Database Results Tasers were deployed on a total of 141 people in 124 events, and discharged 19 times. Of the 141 subjects, 30 (21%) involved people in mental health emergencies. Tasers were more than twice as likely to be discharged at mental health emergencies (8 of 30; 27%) than at criminal arrests (11 of 111; 10%) (X2 = 5.69; df =1; p = .017). There were two incidents of involvement of a Taser as part of police response to inpatient mental health services and two incidents involving mental health community residential accommodation. Conclusions Introduction of Tasers into policing in New Zealand will disproportionately impact on people with mental illness. Guidelines are needed to manage the future use of Tasers in mental health emergencies.

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  • Novel core promoter elements and a cognate transcription factor in the divergent unicellular eukaryote Trichomonas vaginalis.

    Smith, AJ; Chudnovsky, L; Barbosa, Augusto; Delgadillo-Correa, MG; Jonsson, ZO; Wohlschlegel, JA; Johnson, PJ (2011-04)

    Journal article
    The University of Auckland Library

    A highly conserved DNA initiator (Inr) element has been the only core promoter element described in the divergent unicellular eukaryote Trichomonas vaginalis, although genome analyses reveal that only ???75% of protein-coding genes appear to contain an Inr. In search of another core promoter element(s), a nonredundant database containing 5' untranslated regions of expressed T. vaginalis genes was searched for overrepresented DNA motifs and known eukaryotic core promoter elements. In addition to identifying the Inr, two elements that lack sequence similarity to the known protein-coding gene core promoter, motif 3 (M3) and motif 5 (M5), were identified. Mutational and functional analyses demonstrate that both are novel core promoter elements. M3 [(A/G/T)(A/G)C(G/C)G(T/C)T(T/A/G)] resembles a Myb recognition element (MRE) and is bound specifically by a unique protein with a Myb-like DNA binding domain. The M5 element (CCTTT) overlaps the transcription start site and replaces the Inr as an alternative, gene-specific initiator element. Transcription specifically initiates at the second cytosine within M5, in contrast to characteristic initiation by RNA polymerase II at an adenosine. In promoters that combine M3 with either M5 or Inr, transcription initiation is regulated by the M3 motif.

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  • "Sexuality isn't just about sex": Pre-service teachers' shifting constructs of sexuality education.

    Sinkinson, Margaret (2009)

    Journal article
    The University of Auckland Library

    This paper presents the findings of a three-year study into pre-service (student) teachers, experiences of and beliefs about sexuality education in New Zealand schools. It reports on participants, own memories of school sexuality education programmes, and examines changes in their constructs of sexuality education during their teacher education in health education. Comparisons between their original beliefs about what constitutes ,good, sexuality education and those they had developed after three years of teacher education are made. Before beginning and after completing introductory health education courses in 2004, and third year health education specialism courses in 2006, quantitative and qualitative data were collected. Analysis of early data showed that participants saw learning about physical safety and disaster prevention as constituting effective sexuality education. By the end of 2006, although physical safety and avoiding risk were still presented as important aspects of sexuality education, a theme of ,sexuality isn,t just about sex, had emerged. Positive and comprehensive approaches to teaching about sexuality now defined their constructs of sexuality education. Only few participants, however, demonstrated embedded understanding of sexuality as a social construction, or expressed critical or socio-ecological perspectives of sexuality education.

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  • How critical are the tibiofemoral joint reaction forces during squatting in Asian populations?

    Thambyah, Ashvin (2008)

    Journal article
    The University of Auckland Library

    This study examines tibiofemoral joint moments and forces when performing a squat. The relevance of studying such an activity is to understand better the mechanical factors involved in the higher incidence of tibiofemoral osteoarthritis in Asian populations where squatting is a common daily activity. In this study, motion analysis data of walking versus squatting were compared, specifically looking at net external knee flexion moments, ground reaction forces and tibiofemoral contact forces. It was found that while squatting resulted in more than 2.5 times larger peak external moments compared with walking, tibiofemoral contact forces were not significantly different. This was due to reduced ground reaction forces recorded for the squatting phase compared to the larger dynamic effects of deceleration at heel strike during walking. The most significant finding of this study was that in squatting, there was a reversal in the tibiofemoral shear reaction force from posterior-directed to anterior-directed, occurring under full compressive load and within a fraction of a second. It is believed that repeated squatting results in many such reversals in shear reactions that may ultimately have significant implications to the long term mechanical function and structural integrity of the joint cartilage.

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