1,925 results for ResearchSpace@Auckland, 2015

  • Dermal And Cellular Delivery Of An Endogenous Anti-ageing Peptide Using Niosomes

    Badenhorst, Travis (2015)

    Doctoral thesis
    The University of Auckland Library

    Aim: The overall aim of this Thesis was to investigate the physical modification by encapsulation of GHK-Cu, a hydrophilic anti-ageing peptide, with lipid based nano-vesicles to address the barriers to cutaneous and cellular delivery. The influence of the surface charge of the vesicles was particularly studied as it was hypothesized that a cationic charge within the niosomes would increase both cellular and trans-epidermal delivery. The specific objectives were to; (1) evaluate the key physicochemical properties of GHK-Cu for the eventual development of formulations for dermal delivery of this peptide, (2) develop niosomes as a nano-carrier system for GHK-Cu for the potential delivery into the skin, (3) evaluate whether niosomes could act as a potential delivery system to increase cellular absorption as well as trans-epidermal delivery, and (4) evaluate whether the biological effect of GHK-Cu can be improved through niosomal delivery, particularly with cationic niosomes. The mechanisms by which were explored. Methods: The physicochemical properties of GHK-Cu were characterized using conventional methods. High performance liquid chromatography and mass spectrometry was utilised for quantification of the parent compound and identification of degradation products. GHK-Cu was incorporated into niosomal carriers characterised by laser diffraction, transmission electron microscopy (TEM) and zeta potential analysis. Cationic niosomes were chosen and used for the experiments in this Thesis following optimization. A non-ionic niosome of the same composition was used as a reference. Human dermal fibroblasts were used for cellular uptake and intracellular trafficking investigations, imaged with confocal scanning laser microscopy (CLSM) and TEM. All trans-epidermal investigations were undertaken using ex vivo viable human skin using calcein as a fluorescent marker enabling observation with CLSM. The biological response of both niosomal delivery systems was firstly assessed using metalloproteinases (MMP-1, collagenase and MMP-2, gelatinase) and tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2) as markers in cultured primary human dermal fibroblasts. These markers were measured through their gene expression by real time quantitative polymerase chain reaction (RT-qPCR), normalised to the control. Additionally, the collagen and elastin contents was measured in fibroblast cells following GHK-Cu incubation. The Thesis culminated in a double blind placebo split face clinical trial of 40 participants to determine the effect of the encapsulated niosomal GHK-Cu on wrinkle depth and volume reduction. Results: Preformulation studies indicated GHK-Cu was freely water soluble (325.09 ?? 4.38 mg mL-1) and hydrophilic with a logD of -2.49 through -2.38 over pH 7.4 to 4.5. Decreasing the pH caused the reversible dissociation of Cu ions from GHK. This effect proceeded rapidly from pH 4.26 downwards and was primarily caused by the protonation of the imidazole and glycyl residues. Therefore at the HPLC mobile phase with a pH of 2, it was only the GHK peptide that was measured. GHK eluted at 8.02 ?? 0.10 min under isocratic conditions making it ideal for routine analysis. The LOD and LOQ were determined to be 0.55 and 1.8 ??g mL-1, respectively. The validation data, including that from mass spectrometry, proved the assay to be stability-indicating. Forced degradation studies identified hydrolysis as the main pathway of degradation, leading to the identification of three new products. The final product was verified with injections of pure histidine, a component amino acid. GHK was stable in water and in phosphate bufferered saline (0.1 M) at pH 7.4. The logD and solubility results incentivized the consideration of a lipid-based carrier system, in particular niosomes, to enhance the dermal delivery of GHK-Cu. A niosomal lipid based carrier system was subsequently developed for encapsulating GHKCu. The size, surface charge and loading efficiency of the niosomes were optimized to enhance dermal delivery. A positive charge was obtained following post-insertion of didecyldimethylammonium bromide (DDAB) into the surface of Span 60/cholesterol based niosomes. The niosomes had a final size of 225.8 ?? 7.7 nm for cationic and 193.3 ?? 5.2 nm for non-ionic niosomes. A positive surface charge of 49.4 ?? 1.2 mV was observed in cationic niosomes with a maximum entrapment efficiency of 9.7 ?? 0.2% (w/w) of GHK-Cu was achieved for both systems. Calcein, having similar physicochemical properties to GHK-Cu, was chosen for CLSM studies. The mechanism of intracellular uptake, confirmed by TEM imaging, was clathrinmediated endocytosis. This evidence was primarily supported by the size, lysosome formation and clathrin pit formation in fibroblasts. ImageJ analysis of the confocal images showed a slight increase in intensity (83 vs 79) in the cationic treated samples over the nonionic treated ones. A larger number of lysosomes were imaged in cationic niosome treated cells. Endosomal escape was determined to be by destabilisation resulting from both a cationic lipid and a surfactant interaction with the endosomal membrane without affecting the viability of the cells. This was determined using a MTT test, which resulted in all concentrations tested, except that of cationic niosomes at 10-7 M, having no detrimental effect on cell viability. CLSM images revealed that free calcein could not cross the stratum corneum. Niosomes however, both cationic and non-ionic, caused adsorption onto the surface forming a critical thermodynamic activity gradient, driving permeation into the dermis. Upon incubation with niosomes for 24 hours, fibroblasts showed greater expression of MMPs (> 2-fold, p2-fold, p1 suggesting a trend towards decreases in collagen degradation. The ratios of TIMP-2/MMP-2 were <0.005) in wrinkle volume reduction compared to both the placebo and lipophilic derivative. Wrinkle depth also improved the most, however this was only moderately significant (p=0.057). The difference in wrinkle depth and volume versus the placebo indicate the effectiveness of the cationic niosomal GHK-Cu in topical delivery. The cationic encapsulated GHK-Cu was tolerated as well as the marketed Matrixyl?? 3000 product with only one participant reacting to both. Unfortunately the non-ionic niosome formulation was not tested due to financial limitations of the company. Conclusion: GHK-Cu was effectively encapsulated into cationic and non-ionic niosomes and effectively delivered into cells and passed the epidermis with significant biological effect. The in vitro and ex vivo studies essentially proved that cationic encapsulation of GHK-Cu was marginally better than the non-ionic counterpart for intracellular and trans-epidermal delivery. This research, for the first time, found that GHK-Cu could promote the cellular expression of MMP-1, MMP-2 and their inhibitors TIMP-1, TIMP-2 in human fibroblasts, and that it is their ratios that decided the changes in their substrates, collagen and elastin content on/in the cells. The in vivo clinical evidence suggests that dermal delivery of GHKCu in cationic niosomes results in significant wrinkle volume and depth reduction with accumulative improvements.

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  • Discovery and development of imaging-capable bacterial nitroreductases and their cytotoxic prodrugs for Clostridium sporogenes based gene therapy

    Mowday, Alexandra (2015)

    Doctoral thesis
    The University of Auckland Library

    Clostridia Directed Enzyme Prodrug Therapy (CDEPT) has demonstrated anti-tumour efficacy in preclinical studies but has yet to be developed for human clinical trials. Challenges associated with stable genetic modification of the bacterial genome have recently been overcome, making CDEPT clinically feasible for the first time. The main goal of this project was to accelerate the development of nitroreductase-based CDEPT, initially by further improving nitroreductase activity with respect to PR- 104, a clinical-stage 3,5-dinitro-2-mustard prodrug. Random and site-directed mutagenesis techniques were used to optimise the E. coli NfsA polypeptide (UniProt accession P17117) for PR- 104A activation. The preferred multi residue variant #22GP (S41Y, E99G, L103M, R225P, F227S) was successfully expressed in three stable cell line models (HCT116, H1299 and C33A) and demonstrated significantly improved in vitro anti-proliferative activity with PR-104A compared to native NfsA (up to 2.3-fold), whilst retaining the ability to co-metabolise 2-nitroimidazole PET imaging substrates. In parallel, a series of PR-104A analogues were evaluated to eliminate off-mechanism aerobic metabolism by aldo-keto reductase 1C3 (AKR1C3) and to improve therapeutic activity by maximising bystander potency using 2D anti-proliferative and 3D multi-cellular layer assays for E. coli NfsA and/or AKR1C3 activity. In vivo efficacy studies on promising candidates resulted in the selection of a lead compound from each of three chemical classes; SN 34507 (an alcohol bearing 5- nitro-2-mustard phenylcarboxamide), SN 36001 (a piperazine bearing 2-nitro-4-alkylsulfone-5- mustard phenylcarboxamide) and SN 35288 (an alcohol bearing 2-nitro-4-alkylsulfone-5-mustard phenylcarboxamide). Finally, an in vivo model of CDEPT was identified. 1000mm3 H1299 xenografts treated with vascular disrupting agent DMXAA (5,6-dimethylxanthenone-4-acetic acid) produced widespread tumour necrosis and promoted colonisation of nitroreductase expressing Clostridia spores. The combination of DMXAA and Clostridia spores alone produced significant anti-tumour activity compared to untreated controls (TGD = 67%, P=0.004), but the inclusion of prodrug (PR-104) provided significant additional activity (TGD = 167%, P<0.001), validating the CDEPT concept. Successful preclinical evaluation of a transferable gene that metabolises both clinical stage PET imaging agents (for whole body vector visualisation) as well as chemotherapy prodrugs (for conditional enhancement of efficacy) is a valuable early step towards the prospect of nitroreductasearmed C. sporogenes entering clinical evaluation.

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  • A system dynamics view of safety management in small construction companies

    Guo, BHW; Yiu, Tak Wing; Gonzalez, Vicente (2015-12)

    Journal article
    The University of Auckland Library

    Due to unique characteristics of small construction companies, safety management is comprised of complex problems. This paper aims to better understand the complexity and dynamics of safety management in small construction companies. A system dynamics (SD) model was built in order to capture the causal interdependencies between factors at different system levels (regulation, organization, technical and individual) and their effects on safety outcomes. Various tests were conducted to build confidence in the model???s usefulness to understand safety problems facing small companies from a system dynamics view. A number of policies were analyzed by changing the value of parameters. The value of a system dynamics approach to safety management in small construction companies is its ability to address joint effects of multiple safety risk factors on safety performance with a systems thinking perspective. By taking into account feedback loops and non-linear relationships, such a system dynamics model provides insights into the complex causes of relatively poor safety performance of small construction companies and improvement strategies.

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  • The PRC's Doctrine of Non-interventionism Assessed in Comparison with Classical Chinese Conceptions of the Jus ad Bellum

    Lee, Wan Fai (2015)

    Doctoral thesis
    The University of Auckland Library

    This thesis aims to investigate, from a theoretical perspective, whether it is possible to reconcile or to reduce the conceptual divergence between the People???s Republic of China (PRC)???s declared doctrine of non-interventionism and Western norms of liberal internationalism on humanitarian intervention and the responsibility to protect (R2P). Instead of following the nearly fully-excavated path of analysing the post-1949 roots of non-interventionism in the PRC, this thesis concentrates on a careful examination of classical Chinese conceptions that are akin to Western principles of the jus ad bellum. Based on the substantial findings of recently flourished academic debates and publications on the reassessment and adoption of classical Chinese conceptions for the innovation of Chinese foreign relations thoughts, this thesis applies a summarised, self-coined methodology of ???Knowledge Archaeology of Chinese International Relations??? (KACIR) to analyse The Chronicle of Zuo, one of China???s most significant and earliest works of narrative history, and two Confucian texts of philosophy (Mencius and Xunzi) from the pre-Qin era (771-221 B.C.)???a period which demonstrates features comparable to those of modern system of states and international legal order???to see how these texts shed light on the legitimacy and legality problematique in the use of force for humanitarian purposes. The thesis then goes on with a deeper level of analysis: Westphalian principles of sovereign equality, territorial integrity, self-determination and mutual non-interference are not the only factors that have shaped the PRC???s doctrine. Chinese non-interventionism has a deep structure in the intellectual history of China. It is part of the nexus between fundamentalist hermeneutics applied to the pre-Qin canons and the Confucian-Legalist grand narrative of orthodoxy, which has been steering the cognitive mapping of the Chinese in the three dimensions of international ethics???cosmology, worldview, and positive/negative state responsibility???presented through the classical texts. Drawing references from Hans-Georg Gadamer???s theory, this thesis proposes a redefinition of the Chinese tradition and an emancipation of hermeneutics to classical Chinese canons. By replacing fundamentalism with a reinvented cosmopolitanism rooted in universal conscience, it is possible to develop classical Chinese conceptions of the jus ad bellum into an innovative norm or principle of humanitarian intervention and R2P that appears more acceptable than what the PRC views as ???Western-imposed standards??? but is still compatible with liberal internationalism.

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  • Singing communities

    Rakena, Te Oti (2015-04)

    Journal article
    The University of Auckland Library

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  • Singing communities [NZCF]

    Rakena, Te Oti (2015-06)

    Unclassified
    The University of Auckland Library

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  • Extension of Cognitive Behavioral Therapy by emotion regulation training in patients with multiple somatoform symptoms: Results of a controlled pilot study [Erweiterung der kognitiven Verhaltenstherapie um Emotionsregulationstraining bei Patienten mit multiplen somatoformen Symptomen: Ergebnisse einer kontrollierten Pilotstudie]

    Gottschalk, JM; Bleichhardt, G; Kleinst??uber, Maria; Berking, M; Rief, W (2015)

    Journal article
    The University of Auckland Library

    Background: Studies demonstrate that CBT is effective in treating patients with multiple somatoform symptoms (MSS), but by now, the interventions consistently did not exceed medium effect sizes. Since many MSS patients seem to lack emotional awareness, the integration of emotion regulation training could enhance the effects of common psychological interventions. The management of feelings should be enhanced by enriching CBT with emotion regulation strategies like non-judgmental perception, acceptance, and mindfulness. The objective of this study was to validate the ENCERT (Enriching CBT with Emotion Regulation Training) manual, to demonstrate its feasibility and to compare the changes over time with CBT and ENCERT. Patients and Methods: In a non-randomized group study, 20 patients in ENCERT and 22 in CBT (???3 medically unexplained somatic symptoms, ???6 months) attended 20 weekly sessions of individual psychotherapy in an outpatient setting. Assessments took place before beginning and after completion of therapy. Primary outcomes were the Screening of Somatization Disorder (SOMS-7T), emotion regulation skills, and visual analogue scales (VAS) assessing symptom intensity and subjective impairment. Results: Both groups showed significant improvement in the somatization severity index (CBT d = 0.46; ENCERT d = 0.70), as well as in the somatization symptom count (CBT d = 0.50; ENCERT d = 0.72). There were no significant group differences after completion of therapy: Controlling for baseline variables, there was an indication for significant difference between groups in favor of ENCERT in the somatization severity index after completion of therapy (ANCOVA: F (1.37) = 4.058, p = 0.051). Additionally, patients significantly improved during ENCERT in intensity (d = 0.59) and in impairment (d = 1.25) of symptoms, and they reported to acquire greater emotion regulation competence (d = 1.14). Conclusion: Patients with MSS improved during ENCERT and CBT with tendentially larger effect sizes for ENCERT but higher baseline value in depression and anxiety. However, we were not able to find group differences. This might be due to a lack of statistical power. Therefore, our next step is the implementation of a large randomized, controlled multicenter trial.

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  • I Yau Vakaviti: Fijian Treasures in International Museums ??? A Study of Repatriation, Ownership and Cultural Rights

    Vunidilo, Tarisi (2015)

    Doctoral thesis
    The University of Auckland Library

    Pacific islands artifacts and imageries have had a strong appeal to the popular imagination of the West over the years. However, in recent years the question of ownership of intellectual property rights has emerged as many indigenous groups around the world call for the repatriation of their cultural objects taken away, with or without their ancestors??? consent, as a way of reasserting their cultural rights and in rediscovery of their roots and identity. The question of repatriation of cultural objects is now a contentious issue, as indigenous peoples demand the return of their cultural goods from metropolitan museums while museum owners claim ownership of the objects. The creation of indigenous museums adds to this contention as these museums are still deeply entrenched in colonial legacies. It has however shifted indigenous peoples??? views o museum collections and artifacts. The development of cultural centers and the increasing number of indigenous people trained in museology and archaeology goes hand in hand with the political shift in indigenous leadership and self-determination. The anthropological purists tend to view cultural objects fundamentally on the basis of their uses rather than their aesthetic qualities. The interface between functionality and aesthetics makes museum cultural objects a very intricate area of study. Cultural objects are associated with a whole range of cultural and historical contexts including social rank, social change, environmental adaptation, spirituality and daily survival. This research is not meant to examine these in detail but focuses primarily on the appropriation and repatriation of Fijian cultural artifacts. The thesis will attempt to critique the imperial discourse, which conceives of the museum as a space for high culture to sustain European civilisation and the neoliberal approach, which sees cultural objects as commodities and museums as money-making enterprises. It will do so using the postcolonial approach and the application of the Fijian Vanua Research Framework (FVRF). Applying this research framework and enhancing it by using Talanoa as a methodology added value to this research. The combination of interviews and archival research highlighted that the main reason of collecting in the late 1800s and early 1900s was to collect the remaining tangible culture of indigenous societies, in this case Fiji, that were quickly changing under a lot of economical, social and political pressures from outside powers. The research findings highlighted the need to continue discussing repatriation, ownership and cultural rights on all levels of society-from local, national, regional and international platforms. Fiji and its Pacific island neighbors must work together to develop new theories, research frameworks and methodologies that work for and by Pacific peoples. It is widely known that Pacific heritage art is an area that is in dire need of research. Indigenous writers and researchers need to support one another to conduct more evidence based writing on the arts from a Pacific Islander standpoint. The hope is that this research will contribute to the ongoing debate and policy formulation on cultural consolidation and reform in the Pacific face of globalisation as Pacific people attempt to relive history, reconnect with the ancestral past and reconstruct their identities.

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  • A confirmatory factor analytic validation of the Tinnitus Handicap Inventory

    Kleinst??uber, Maria; Frank, I; Weise, C (2015)

    Journal article
    The University of Auckland Library

    Objective Because the postulated three-factor structure of the internationally widely used Tinnitus Handicap Inventory (THI) has not been confirmed yet by a confirmatory factor analytic approach this was the central aim of the current study. Methods From a clinical setting, N = 373 patients with chronic tinnitus completed the THI and further questionnaires assessing tinnitus-related and psychological variables. In order to analyze the psychometric properties of the THI, confirmatory factor analysis (CFA) and correlational analyses were conducted. Results CFA provided a statistically significant support for a better fit of the data to the hypothesized three-factor structure (RMSEA = .049, WRMR = 1.062, CFI = .965, TLI = .961) than to a general factor model (RMSEA = .062, WRMR = 1.258, CFI = .942, TLI = .937). The calculation of Cronbach's alpha as indicator of internal consistency revealed satisfactory values (.80???.91) with the exception of the catastrophic subscale (.65). High positive correlations of the THI and its subscales with other measures of tinnitus distress, anxiety, and depression, high negative correlations with tinnitus acceptance, moderate positive correlations with anxiety sensitivity, sleeping difficulties, tinnitus loudness, and small correlations with the Big Five personality dimensions confirmed construct validity. Conclusion Results show that the THI is a highly reliable and valid measure of tinnitus-related handicap. In contrast to results of previous exploratory analyses the current findings speak for a three-factor in contrast to a unifactorial structure. Future research is needed to replicate this result in different tinnitus populations.

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  • The changeability and predictive value of dysfunctional cognitions in cognitive behavior therapy for chronic tinnitus

    Conrad, I; Kleinst??uber, Maria; Jasper, K; Hiller, W; Andersson, G; Weise, C (2015)

    Journal article
    The University of Auckland Library

    Background Multidimensional tinnitus models describe dysfunctional cognitions as a complicating factor in the process of tinnitus habituation. However, this concept has rarely been investigated in previous research. Purpose The present study investigated the effects of two cognitive-behavioral treatments on dysfunctional tinnitus-related cognitions in patients with chronic tinnitus. Furthermore, dysfunctional cognitions were examined as possible predictors of the therapeutic effect on tinnitus distress. Method A total of 128 patients with chronic tinnitus were randomly assigned to either an Internet-delivered guided self-help treatment (Internet-based cognitive-behavioral therapy, ICBT), a conventional face-to-face group therapy (cognitive???behavioral group therapy, GCBT), or an active control group in the form of a web-based discussion forum (DF). To assess tinnitus-related dysfunctional thoughts, the Tinnitus Cognitions Scale (T-Cog) was used at pre- and post-assessment, as well as at the 6- and 12-month follow-up. Results Multivariate ANOVAs with post hoc tests revealed significant and comparable reductions of dysfunctional tinnitus-related cognitions for both treatments (GCBT and ICBT), which remained stable over a 6- and 12-month period. Negative correlations were found between the catastrophic subscale of the T-Cog and therapy outcome for ICBT, but not for GCBT. This means a higher degree of catastrophic thinking at baseline was associated with lower benefit from ICBT directly after the treatment. Hierarchical regression analysis confirmed catastrophizing as a predictor of poorer therapy outcome regarding emotional tinnitus distress in ICBT. No associations were detected in the follow-up assessments. Conclusion Both forms of CBT are successful in reducing dysfunctional tinnitus-related cognitions. Catastrophizing significantly predicted a less favorable outcome regarding emotional tinnitus distress in ICBT. Clinical implications of these results are described. Dysfunctional cognitions could be targeted more intensively in therapy and in future research on tinnitus.

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  • Effect of liquid fraction and bubble size distribution on the polarised light scattering characteristics of Casein foam

    Qian, S; Chen, John (2015-01-27)

    Journal article
    The University of Auckland Library

    A polarised light scattering experimental set-up was designed to conduct experiments using Casein foams with monodispersed and bidispersed bubble size distributions. Foams were initially generated under forced drainage conditions to maintain a uniform axial liquid fraction profile. Subsequently, the foams entered a free drainage period. During this period, the liquid fraction, the bubble size distribution and the polarisation parameters of scattered light due to the foam were measured individually. It was found that both the liquid fraction and the bubble size distribution of Casein foams varied simultaneously with drainage time. Therefore, multiple regression analysis was performed to investigate the individual effect of these two foam factors on the polarisation state. Four of the polarisation parameters (degree of polarisation, degree of linear polarisation, degree of circular polarisation, ellipticity angle) were shown to be associated with the liquid fraction and/or the bubble size distribution to different extents. However, the remaining parameter, orientation angle, was completely independent of the liquid fraction and the bubble size distribution. These results can be used for the development of the polarised light scattering method in the study of protein foams.

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  • Peak load shifting with energy storage and price-based control system

    Barzin, R; Chen, John; Young, Brent; Farid, Mohammed (2015-12-01)

    Journal article
    The University of Auckland Library

    This paper presents an analysis of a price-based control system in conjunction with energy storage using phase change materials for two applications: space heating in buildings and domestic freezers. The freezer used for this experimental study was provided with energy storage trays containing a eutectic solution of ammonium chloride (melting point of -15??C). In the building application, DuPont wallboards were used to provide thermal storage. Experimental results showed that using thermal storage material in conjunction with the proposed price-based control method can improve performance of these systems and lead to a successful peak load shifting. Depending on electricity price trends, cost savings using the proposed strategy can vary. Savings of up to 16.5% and 62.64% per day were achieved for the freezer and building applications respectively, based on New Zealand electricity rates.

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  • Application of PCM energy storage in combination with night ventilation for space cooling

    Barzin, R; Chen, John; Young, Brent; Farid, Mohammed (2015-11-15)

    Journal article
    The University of Auckland Library

    In recent years, as a result of the continuous increase in energy demand, the use of energy storage has become increasingly important. To address this problem, the application of phase change materials (PCM) in buildings has received attention because of their high energy storage density and their ease of incorporation in building envelopes. Despite large experimental works conducted on the application phase change materials in buildings, there is very little work done on this application in combination with night ventilation. In this study, the application of night ventilation in combination with PCM-impregnated gypsum boards for cooling purposes was experimentally investigated. Two identical test huts equipped with ???smart??? control systems were used for testing the concept. One hut was constructed using impregnated gypsum boards, while the other hut was finished with ordinary gypsum board. Initially an air conditioning (AC) unit, without night ventilation, was used in both huts to charge the PCM during low peak period, showing very little savings in electricity. However, when night ventilation was used to charge the PCM instead, a weekly electricity saving of 73% was achieved.

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  • SERUM TESTOSTERONE LEVELS RELATE TO BOTH FRAILTY AND ADL IN OCTOGENARIAN MALES: LILACS STUDY, NEW ZEALAND

    Connolly, Martin; Kerse, Ngaire; Moyes, Simon; Wilkinson, T; Rolleston, R; Chong, YH; Menzies, O; Broad, Joanna; Jatrana, S; Teh, Ruth (2015-09)

    Journal article
    The University of Auckland Library

    Serum testosterone (T) levels in men decline with age. Low T levels are associated with sarcopenia and frailty in ???younger old??? men (generally <80 years). T levels have not previously been associated with disability in older men, despite associations between T and physical function and quality of life. There is no consensus on whether older men with low T levels should receive testosterone supplementation to prevent/???treat??? frailty. We explored associations between T levels and both frailty and disability in a cohort of octogenarian males.

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  • Perioperative use of chewing gum affects the inflammatory response and reduces postoperative ileus following major colorectal surgery

    Su'a, BU; Hill, Andrew (2015-10)

    Journal article
    The University of Auckland Library

    Postoperative ileus (POI) affects one in four patients undergoing major elective abdominal surgery. It is associated with prolonged hospital stay and other postoperative complications, and carries a significant financial burden on healthcare facilities.1 Some studies suggest the inhibition of the inflammatory response after surgery may reduce the development of POI. Chewing gum is hypothesised to exert an effect via reduction of postoperative inflammation through cephalic vagal activation. Although a number of systematic reviews and meta-analyses have been published, the role of chewing gum in POI still remains unclear.2 Additionally, with the advent of enhanced recovery after surgery (ERAS) protocols, which encourage early feeding, the use of chewing gum has become less clear. This trial examines the effect of gum chewing before and after colorectal surgery on POI, surgical complications, length of hospital stay (LOS) and inflammatory parameters.

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  • Likelihood of residential aged care use in later life: a simple approach to estimation with international comparison

    Broad, Joanna; Ashton, Toni; Gott, Caryl; McLeod, H; Davis, Peter; Connolly, Martin (2015-08)

    Journal article
    The University of Auckland Library

    In New Zealand (NZ), place of death among decedents aged 65+ years has been reported as residential aged care (RAC, 38%), acute hospital (34%) or elsewhere (28%). However, lifetime risk of use of RAC (or nursing homes) is unknown. A simple method of estimation is demonstrated for NZ and Australia, with comparisons to other countries.Deaths of RAC residents in acute hospitals were estimated for NZ from four separate studies and added to deaths occurring in RAC, to derive the likelihood of using RAC after age 65 years. Academic and other sources were searched for comparative reports.An estimated 18% of RAC residents died in acute hospital in NZ. When added to those who died in RAC, the proportion using RAC for late-life care was estimated at over 47% (66% if aged 85+ years). Of 12 US reports, the median report was 41%. Elsewhere, Finland was 47%, UK 28%, Australia 34% to 53%, and Germany 22% & 26%.Simple estimation using existing data demonstrates that RAC in late life is common.Late-life care services will continue to evolve. Monitoring RAC utilisation is necessary for informed debate about palliative care provision in RAC, use of hospital by RAC residents and for planning and policy setting.

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  • Is digital storytelling ka pai for New Zealand M??ori? Using digital storytelling as a method to explore whanau end of life caregiving experiences: A pilot study.

    Williams, L; Moeke Maxwell, T; Kothari, Shuchi; Pearson, Sarina; Gott, M; Black S; Frey, Rosemary; Wharemate, R; Hansen, W (2015-04)

    Conference item
    The University of Auckland Library

    Maori regard stories as a preferred method for imparting knowledge through waiata (song), moteatea (poetry), kauwhau (moralistic tale), pakiwaitara (story) and purakau (myths). Storytelling is also an expression of tinorangatiratanga (self-determination); Maori have the right to manage their knowledge, which includes embodiment in forms transcending typical western formulations. Digital storytelling is a process by which 'ordinary people' create short autobiographical videos. It has found application in numerous disciplines including public health and has been used to articulate the experiences of those often excluded from knowledge production. This publication is an outcome of a poster session about the this project presented at The Public Health and Palliative Care conference in Bristol (May 11-13, 2015)

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  • Method of stimulus combination impacts resistance to extinction

    Podlesnik, Christopher; Bai, John (2015-07)

    Journal article
    The University of Auckland Library

    Reinforcing an alternative response in the presence of the stimuli governing a target response increases resistance to extinction of target responding, relative to training target responding on its own. Conversely, training alternative and target responses in the presence of different stimuli and combining those stimuli only decreases resistance to extinction of target responding, relative to target responding on its own. The present study assessed how different methods of combining discriminative stimuli influence resistance to extinction of responding in pigeons. As in previous studies, combining stimuli across different keys only decreased resistance to extinction of target responding relative to target responding on its own. In comparison, combining stimuli on the same key initially increased resistance to extinction of target responding, but repeated tests resulted in similar levels of responding as target responding with stimuli combined on separate keys. Moreover, greater overall reinforcement rates produced greater resistance to extinction with both methods of combining stimuli, consistent with behavioral momentum theory. These findings reveal several behavioral processes influence the outcome of combining stimuli--including perceptual processes, discriminative control by contingencies, response competition, and behavioral momentum.

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  • Calorimetry of a harmonically trapped Bose gas

    Ruddell, SK; White, Donald; Ullah, A; Baillie, D; Hoogerland, Maarten (2015)

    Journal article
    The University of Auckland Library

    We study experimentally the energy-temperature relationship of a harmonically trapped Bose-Einstein condensate by transferring a known quantity of energy to the condensate and measuring the resulting temperature change. We consider two methods of heat transfer, the first using a free expansion under gravity and the second using an optical standing wave to diffract the atoms in the potential. We investigate the effect of interactions on the thermodynamics and compare our results to various finite-temperature theories.

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  • Exemplifying a Continuum of Collaborative Engagement: Raising Literacy Achievement of At-Risk Students in New Zealand

    Parr, Judith; Timperley, Helen (2015)

    Journal article
    The University of Auckland Library

    This article reports different ways researchers work with stakeholders in national projects targeted at raising achievement of students. Specifically, New Zealand has a persistent high performance???low equity profile in international tests, with indigenous M??ori students and immigrants from the Pacific Islands most at risk of underachievement and of leaving school without qualifications. Policy has aimed to address this issue largely through provision of high-quality professional development to enhance effectiveness of practice. The notion of a continuum of collaboration is proposed; examples are presented that are positioned at different points in terms of the ideal of coconstructed, evidence-based judgments and decisions. The examples represent models or ways of working and the analysis captures both the varied nature of the interface that researchers have with policy makers, ministry officials, deliverers of professional development, and schools, and the affordances and tensions that accompany each model. Student achievement outcomes are identified.

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