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An evaluative study of participatory development: the dynamics of rural community develoment in Sarawak
Get PDFParticipation and communication are key terms in the study, and they work in tandem. They raise the need for dialogic communication and collaborative activities to foster empowerment and greater interaction for the villagers of Kampung Opar and Sebauh longhouses, the sites of my research, so that they can assert their role in community development planning and decision making. With development policy and implementation generally taking a top-down approach, politics and power relations remain a powerful factor of influence, limiting the social space for freely occurring group or community-initiated participatory activities.
Residents of a longhouse in Bintulu and villagers in Kampong Opar were studied. Online and in-person interviews were also conducted with more than 50 Dayak personalities from the Dayak Iban and Dayak Bidayuh communities. The majority of the latter are professionals or university-educated. They hail from the two villages but have set up their second home in towns where they run their businesses or are in employment. They return home to their villages at least once a month and maintain strong links with their ancestral homes.
Dialogic communication, which is a fundamental component of participatory development, underpins human development by allowing people to access, create, and share information that is critical to their empowerment and participation in development and progress. Paolo Freira's horizontal approach is used to lend credibility and support to a people-centred movement that maximises the use of local resources and talents to motivate and lead the communities of Kampung Opar and Sebauh longhouse on a shared path towards participatory development.
Although there are theories and models in the social science literature on community participation, participatory development, and participatory communication, the majority of them are based on western thinking and ideas that focus mechanistically on the process of information and resource development, information sharing, and knowledge-driven empowerment while excluding elements of culture and religion.
In my research, I extended and adapted existing models of community participation to include religion and culture as important factors in social capital formation because they can be effectively used to create collective identity and drive participatory communication. While participatory development is associated with dialogue, self-sufficiency, and empowerment, the socio-cultural context of communities is equally important and plays a role in the participatory communication and development cycle. Quality research is used primarily in carrying out the study, with emphasis on understanding and explaining the social phenomena, characteristic behaviour, experiences, values, psyche, and relationship behaviour of the people in the two communities (Kampung Opar and Sebauh longhouse). The social dimension is essential in the formulation and development of participatory development policies and frameworks. The government authorities in Sarawak do not deny the importance of people's participation in community development or the critical role that dialogic communication plays in creating a democratic corridor to facilitate the process of negotiation and meaning exchange. The issue is that they see communication primarily as the transmission of messages to the community. This must be corrected. This would entail a review of the current local government structure and accountability pattern, as well as the state ordinance governing the structure and powers of the local government.
In my study, a preferred option is a "integrated participatory innovation platform," which is a process model that integrates the efforts of stakeholders such as local government, community leaders, politicians, NGOs, and the private sector in relation to local development. It would help to break the impasse and lay the groundwork for greater and more effective participation, on which the community and local government could collaborate to improve community-local government relations and empower community members.
It is hoped that the 'integrated participatory innovation platform" will facilitate the creation of a bigger space for power and opportunities for the community and provide the way forward for participatory development for rural communities in Sarawak
Leadership roles of principals in international secondary schools: evidence from Malaysia
Get PDFThe number of international schools globally has been growing exponentially in the last few decades. Malaysia has a similar growth rate of international schools during these two decades. As more international schools are established, more principals are required to lead the schools. This study focuses on the role of principals in leading international secondary schools in Malaysia.
A two-stage mixed methods explanatory sequential design was adopted for data collection. An electronic questionnaire survey was sent to a census sample of 109 international secondary school principals in Malaysia in the first stage, with a response rate of 31.2%. Interviews were conducted with five participants in each of the three case study schools in the second stage. Methodological triangulation is used to improve reliability and validity of the study, through the quantitative survey and qualitative interviews, and respondent triangulation is addressed through asking similar questions to interview participants at different levels. Finally, comparison and triangulation take place based on the responses given by the interviewees, and also through responses from the survey questions.
The findings from the survey implies that the origins of the principals may have played an important part in their recruitment to an international school in Malaysia. This expectation is supported by the superordinates of the three case study schools. The main selection processes in the recruitment of principals were through face-to-face and Skype interviews. In terms of role relationships with different stakeholders, more principals rate the relationships as excellent or good, as compared to poor or very poor. This finding is similar to the ratings at the three case study schools, supported by the superordinates and SLT members. This study is a substantial addition to the existing knowledge on the roles of international secondary school principals in Malaysia as there is direct evidence from such principals through both survey and interview data. The multidirectional trust between principals, and their superordinates and subordinates, affects mutual relationship building, and may also impact on the tenure of a principal
Ex vivo Spider silk, an exploration of the novel method for the dissection and culturing of spider silk glands.
Get PDFThis thesis will detail the novel system that has been developed to dissect out and maintain in culture the glands that produce a spider’s silk. As well as the findings surrounding the internal structures of the gland’s cells, this study system will allow exploration of how the glands function under stress and provide potential avenues for future applications and study. This will be done in three parts. Firstly, describing the methodologies for the removal and culture of the silk glands as well as the confirmatory work to show the glands are not just surviving, but actively producing silk. Secondly the exploration of the observational data made possible through viewing the glands in culture. Finally, showing the materials research that is possible through having access to previously inaccessible liquid silk dope for testing, the work surrounding the new methodology for the dissolution and reprinting of native spun spider silk, and the insights this gives us into the way silk proteins fold and organise in the gland that produces one of the most studied biomaterials in the natural world
Deep learning for cardiac MRI segmentation and event prediction with extracted features
No full textBackground: Ventricular Tachycardia (VT) is associated with significant mortality and morbidity. Ischaemic Heart Disease (IHD) can predispose individuals to VT through the presence of anatomical substrate (i.e. scar). Management of VT remains challenging with progression to ablation not uncommon and high risk of recurrence. Cardiac magnetic resonance imaging(CMR), particularly late-gadolinium enhanced (LGE) MRI, is beneficial for procedures through the identification of scar, thereby facilitating scar localisation, navigation of ablation as well as, through quantification, VT risk prediction. Unfortunately, the task of segmentation for either purpose is resource-intensive with suboptimal reproducibility and scar quantification does not appreciate scar complexity or identify high risk scar. Artificial intelligence (AI) can be used to rapidly and reproducibly undertake routine tasks utilising unseen features and associations in data. Its application to LGE CMR for reproducible, rapid scar segmentation has significant potential. Furthermore, subsequent extraction of data from that scar for risk prediction may be beneficial.
Aims: This thesis aims to explore applications of AI to LGE CMR for patients at risk of VT with IHD. A particular focus is placed on cardiac structure & scar delineation and prediction of clinical events.
Methods: (1) A systematic review of current scar segmentation was undertaken to identify key limitations in current models. (2) A deep learning, multilabel model was developed utilising a new, large, disease specific CMR dataset – collected and labelled with clinical data. Inter- and intra-rater assessments were undertaken to reinforce confidence in underlying labels. Testing utilised multi-model evaluation. (3) Validation of the model was undertaken utilising an external cohort. (4) Features were extracted from original labels using a bespoke developed program and assessed for reproducibility. Exploratory univariate analysis with arrhythmia and all-cause mortality were undertaken after correction for co-linearity and dimension reduction.
Results & Conclusions: (1) Feasibility of LGE CMR segmentation is shown with significant limitations in sample size, disease aetiology and application to VT. (2) Performance of the multilabel segmentation model was in keeping with previously published models with the advantage of additional structure labelling for VT ablation and building on previous limitations. (3) External validation was suboptimal, potentially due to distribution shift. The need for large, varied databases for model development including multiple scanners and sequences was highlighted. (4) Several features were associated with clinical endpoints resulting in hypothesis generation and requiring future confirmatory studies. Based on findings and limitations of data availability throughout the study, a prospective, multicentre paired imaging and clinical database has been designed and recruitment started to expand available datasets for further segmentation and prediction model refinement and testing. In addition, a retrospective study between LGE CMR findings and invasive electrophysiological testing has started recruitment for early assessments of clinical correlation
Valorisation of hop co-products for their phenolic content and antioxidant properties.
Get PDFThere is growing interest in the valorisation of agricultural and food processing residues for their functional bioactive compounds, due to high availability, low cost and alignment with a circular economy model. The harvesting and processing of hop cones for the brewing industry generates co-products which contain phenolic compounds of potential value to the cosmetic, food and beverage sectors due to their antioxidant properties. This study aimed to evaluate these co-products as a source of natural phenolics by producing extracts with high antioxidant activity using scalable, green extraction and purification techniques. Purified hop phenolic fractions were benchmarked against commercially available phenolic antioxidants produced from non-hop sources.
In experiments reported in Chapter 3 the focus was on optimising the extraction of phenolics from hop processing residue (cv. Herkules) using aqueous ethanolic solutions. A response surface methodology was adopted to evaluate the effects of; ethanol % of extraction solvent (30-90%), and solid: liquid ratio (100-150 mg/ml). Ethanol % was highly significant (P0.05) impact on any of those response variables. A range of commercial enzymes (cellulases, pectinases and proteases) and incubation conditions were evaluated to see if they could increase the release of bound phenolics, however no treatments resulted in significantly greater extraction (p>0.05). It was concluded that optimal extraction conditions for the simultaneous extraction of TPC, PAC and xanthohumol were 50% ethanol (v/v) at 100mg/ml with no hydrolytic enzymes.
These extraction conditions were then applied to a range of hop co-products and non-hop materials (Chapter 4) to characterise their phenolic composition and antioxidant activity. Hop co-product extracts generally had higher phenolics content and antioxidant activities compared to non-hop materials. Phenolic structural elucidation and quantitation using LC-ESI-qTOF-MS/MS showed that prevalent hop co-product phenolic fractions include flavanols, B-type procyanidins, flavonol glycosides, prenylflavonols and chlorogenic acids. The phenolic profile of co-products depended on the co-product stream and hop variety, with prenylflavonols being abundant in CO2 extract residues, catechins and procyanidins in T45 pelleting residues, and flavonol glycosides and chlorogenic acids in hop leaves. Notably, Herkules CO2 extract residue was found to be a rich source of prenylflavonoids, in particular xanthohumol (9.1 mg/g DM), a prenylflavonoid with potent hydroxyl and peroxyl scavenging activities and anti-cancer properties. Herkules CO2 extract residue is also the most available material to industry and was therefore selected for subsequent attempts to generate purified, more concentrated hop phenolic extracts.
In Chapter 5 the use of different adsorption resins (PVPP and PAD950) and ultrafiltration membranes (UFX10, FS40, GR51) were investigated for the purification of phenolics from Herkules CO2 extract residue. The phenolic purity and antioxidant activity of purified extracts from CO2R-HERK strongly depended on the purification technique used. The highest purity extract was produced via adsorption with PAD950 resin, and was mainly composed of catechins, B-type procyanidins and flavonol 3-O-glycosides. Ultrafiltration was much less effective across a range of membrane cut-off sizes evaluated (10-100 kDa) indicating that PAD950 SPE offers greater phenolic specificity as compared to molecular weight size exclusion techniques. Langmuir isotherm modelling demonstrated high adsorption capacities of PVPP for hop phenolics (in particular xanthohumol), for both E0 and E50 feed solutions. However, recovery rates using ethanol, ethyl acetate and ammoniacal ethanol of varying strengths were generally ineffective for phenolic recovery using a fixed bed column setup.
Later work (Chapter 6, 7) comprehensively evaluated hop leaves as a source of phenolic antioxidants by sourcing three commercially significant varieties grown in Yakima, sampled at different developmental stages and crop years. The phenolic profile of hop leaves exhibited considerable structural diversity and differed significantly from that of respective cones. Kaempferol and quercetin 3-O-glycosides as well as chlorogenic acids were the most abundant sub-groups, with phenolic acids, procyanidins, prenylflavonoids and bitter resins also present. Multi-variate analysis indicated that the phenolic profile of hop leaves was primarily variety-dependent and driven largely by the composition of flavonol glycosides, with crop year and developmental stage showing smaller and less consistent effects. Compared to South African hop leaf extracts, Yakima hop leaf extracts exhibited significantly lower total phenolic contents but higher flavonol glycoside levels, highlighting the variability in phenolic content among hop leaf sources.
In Chapter 8 the antioxidant activities of hop leaf extracts were evaluated and correlated with phenolic compound concentrations in the samples. Pearson’s correlation analysis revealed significant positive correlations for B-type procyanidins and catechins (P99%) and significant increases in antioxidant activity depending on glycoside composition and antioxidant mechanism assayed. Cascade leaf extract exhibited the greatest increases in antioxidant activity (FRAP 4.5*) likely due to the high kaempferol 3-O-rutinoside content (400.56 mg/g). These findings highlight the potential for hydrolytic treatment of hop leaf extracts to generate natural antioxidants
Investigating sensorimotor representations, processing and inhibition in Tourette Syndrome: Insights from fMRI, MRS and TMS
Get PDFTourette Syndrome (TS) is a hyperkinetic neurodevelopmental movement disorder, characterised by motor and phonic tics, and has been associated with disruptions to cortical inhibition. y-aminobutyric acid (GABA) is the most abundant inhibitory neurotransmitter in the cortex. GABA has been linked to both the integrity of cortical representations and performance in the discrimination of tactile stimuli. In populations with disruptions to cortical inhibitory functioning, such as Focal Hand Dystonia (FHD) which involves involuntary repetitive movements of the hand, abnormalities are evidenced in cortical sensorimotor representations of the fingers and hand muscles. Additionally, individuals with FHD display abnormalities in the processing of sensory stimuli. Many individuals with TS also report experiences of abnormalities in sensory processing, such as premonitory urges (PU) prior to tics and hypersensitivity to external stimuli such as light, sound and touch. However, sensitivity to external stimuli has not been widely investigated in TS, despite being a source of discomfort. Moreover, there is mixed evidence regarding inhibitory abnormalities within the sensorimotor cortices, and a lack of insight into cortical representations of movements relating to tics.
This thesis first aimed to examine quantitative tactile sensory thresholds and magnetic resonance spectroscopy (MRS) measures of GABA and glutamate in individuals with TS. Chapter 3 demonstrated that quantitative sensory thresholds show abnormalities in adults with TS in comparison to typically developing (TD) controls. Moreover, a trend for reduced sensorimotor MRS-GABA was evident in the TS group. However, MRS-GABA and quantitative sensory thresholds were not correlated in both TS and TD groups.
In addition to quantitative sensory detection performance and MRS-GABA in TS, cortical representations were investigated. In Chapter 4 and 5, functional magnetic resonance imaging (fMRI) was utilised to determine if there are differences between adults with TS and TD controls in sensorimotor representations of the digits (unrelated to tics) and facial movements of common tics (blinking, grimacing and jaw clenching). Moreover, fMRI responses of vibrotactile stimulation to the three sites of the face were compared across groups. While digit and vibrotactile facial maps showed some differences between groups, no differences were apparent between sensorimotor representations of facial movements. However, a conjunction analysis revealed the SMA activation was not consistently active across all facial movements in the TS group, whereas the SMA was consistently activated in the TD control group. This is in line with previous evidence of individuals with TS showing abnormalities in SMA activation when performing volitional movements.
Finally, Chapter 6 aimed to assess if manipulating GABAergic inhibition with intermittent theta-burst stimulation (iTBS) would result in changes to cortical motor representations of the digits measured with transcranial magnetic stimulation (TMS) and fMRI. While TMS measures revealed reductions in inhibition in individuals receiving active iTBS, inconsistent differences were evident in digit maps in both active and control groups. Coupled with a low number of participants, it was unclear if any differences in digit maps between groups were a direct result of the stimulation, or instead due to variability in iTBS after-effects and variability within the data
Magnetic Resonance Imaging and Spectroscopy Methods for Studying Obesity: Applications for Bariatric Surgery
Get PDFThe prevalence of obesity in the population is increasing globally, leading to a rise in metabolic disorders such as Type-II Diabetes (T2D). Magnetic Resonance Imaging (MRI) and Spectroscopy (MRS) provide safe non-invasive techniques for investigating the physiology and metabolism of the human body. Whilst multinuclear MRS allows metabolic pathways that cannot be measured using 1H methods to be probed, in this thesis 13C and 31P MRS are used to study liver metabolism.
This thesis first provides an outline of the necessary biology and NMR theory to introduce the four experimental chapters. The first experimental chapter, Chapter 3 describes a clinical study using multiparametric 1H MRI and MRS to investigate the changes that occur in T2D and pre-diabetic patients across the bariatric surgery journey. Participants are scanned at 4 timepoints: baseline, following a Very-Low Calorie Diet (VLCD) that precedes surgery, and 6 weeks and 24 weeks post-surgery. MRI findings of the changes in the volume of Subcutaneous Adipose Tissue (SAT) together with volume, fat fraction and MR relaxometry of the liver, spleen, and pancreas measures, are discussed.
The field of multinuclear MRS is ever-growing. However, there are many challenges to applying this research technique to clinical groups with further challenges in obese individuals. Chapter 4 describes the optimisation of RF excitation pulses for abdominal multinuclear MRS using a single-loop surface coil. Block and Half-Passage Hyperbolic Secant pulses for non-localised 13C and 1D ISIS 31P MRS acquisitions are explored including B1 field simulations. Simulations using 13C were compared to experimental data taken in a phantom. 31P MRS measures are then tested in vivo to study the change in Signal-to-Noise Ratio (SNR) with distance from the surface coil. Methods are then used to inform 31P MRS saturation transfer experiments investigating changes to ATP flux in the liver in two intervention studies, the first on the effect of consuming Inulin Propionate Ester (IPE), a dietary fibre, and the second studying changes following bariatric surgery.
A high Number of Signal Averages are needed for natural abundance multinuclear MRS due to low SNR, resulting in spectra typically acquired whilst free breathing. Chapter 5 explores the effects of respiration on liver 1H spectra as an analogue for understanding the effect of respiration on multinuclear MRS. The shifts in the 1H MRS liver water peak central frequency, Full-Width Half Maximum and amplitude are evaluated and compared to shifts seen in imaging-based dynamic and breathheld liver B0 maps. Implications of the results for multinuclear MRS are discussed.
Ensuring the reproducibility of any data is key to its scientific value. In the final experimental chapter, Chapter 6, the reproducibility of 13C liver MRS after a tailored meal and overnight fast is assessed. Measures of inter subject and intra-subject reproducibility are assessed, as well as intra-rater and inter-rater reproducibility, for two raters and an automatic analysis pipeline.
Finally, a summary of key findings and proposals for future work are provided
Functionalising and Preserving Blood Platelets for Biologically Targeted Gene Therapies
No full textBlood platelets possess the unique ability to target wounds or inflammatory sites and to initiate clotting to prevent bleeding in severe trauma. Platelets also play important roles in several disease processes such as cancer cell invasion and metastasis. In recent years gene therapy has become an accepted branch of advanced therapy, and the use of primary cells such as platelets, as gene or drug delivery systems offers many potential applications. Platelets and/or platelet mediated gene therapy could therefore have applications in cancer therapy, as well as after surgery due to their anti-inflammatory/regenerative abilities and could deliver novel genes and gene products if they are transfected with foreign DNA. However, to date, there is an imbalance between the requirement for platelets and their availability, due to their short shelf life and the absence of appropriate storage. Better methods for platelet preservation and non-viral methods for platelet transfection could therefore facilitate wider deployment of platelet-based therapeutics. This study aimed to examine the applicability of platelets as a delivery route for genetic cargo into cells, allowing for targeted cancer therapy. To accomplish this a cell-penetrating, peptide based non-viral vector that utilises glycosaminoglycan binding enhanced transduction (GET) was used to deliver plasmid DNA into human platelets. To evaluate whether plasmid DNA carrying the Gaussia luciferase gene was delivered into platelets using the GET-peptide system. Luciferase assays were performed and results demonstrated platelets and GET/DNA complexed together was able to transfect target cells. Adding thrombin to this formulation resulted in an increase in transfection efficiency and this enhancement was combined with an increase in platelet activation as measured using an antibody that recognises CD-62 labelled with FITC as an activation marker. Using a platelet adhesion assay, the binding of platelets to different types of cancer cells was investigated. Calcien-labelled platelets adhered to breast, bile duct, and colorectal cancer cell lines. Furthermore, exposure to platelets resulted in increased cancer cell migration in all of the tested cell lines. Analysis of bile duct cancer cells lines showed that platelet treatment also increased cell number over time and impacted cell cycle progression. These data highlight a concern with using platelets for cancer gene therapy, since platelets might increase cancer cell migration and proliferation as well as delivering potentially therapeutic molecules. To address this, exhausted platelets were prepared by treating the platelets with thrombin to induce their activation and then using centrifugation to collect the exhausted platelets. The adherence of exhausted platelets to cancer cells was shown to decrease by around 30%, and decreased effects on cancer cell migration. However, exhausted platelets had very little stimulatory effect on cancer cell metabolic activity when compared to resting platelets. Finally, the potential of trehalose as a platelet cryoprotectant was investigated. Measurement of metabolic activity using a presto-Blue assay showed that trehalose improves cryopreservation compared to a control lacking trehalose. To determine whether cargo loaded platelets can function in cargo delivery after cryopreservation, cargo delivery was measured before and after cryopreservation. Platelets cryopreserved before loading with cargo demonstrated lower efficacy compared to platelets loaded and then cryopreserved. This highlights the significant challenge in maintaining platelet functionality through the loading and cryopreservation process. In summary this work provides new insights into the possibility of using platelets as a delivery system as well as highlighting the need for designing and implementing effective techniques for preserving platelets and extending their shelf life
Investigating the Aroma Chemistry of Dendrobium Stems (Chinese Name: Shihu)
No full textPeople have consumed dried Dendrobium stems, known in China as Shihu, for thousands of years as food and traditional medicine. Shihu is valued for its potential health benefits and flavour attributes, and for this reason, it is well integrated into traditional Chinese cooking, and more recently, become a modern ingredient in nutraceutical drinks. Shihu contains a diverse range of volatile compounds and glucomannan polysaccharides. However, there are gaps in the knowledge of the compounds responsible for its aroma and their formation, and this thesis aims to investigate these important compounds through: 1) comprehensively investigating the aroma compounds of Dendrobium stems, focusing on 2) key aroma-active compounds, 3) assessing drying's impact on aroma formation and 4) evaluating flavour stability. Instrumental analysis was used to characterise and semi-quantify volatile aroma compounds, identify those responsible for the aroma, quantify flavour precursors, and evaluate aroma stability. Gas Chromatography-Mass Spectrometry (GC-MS) identified 21 aroma compounds in commercially available dried Shihu. Varying oven drying temperatures and durations impacted both the aroma compounds and moisture content (Chapter 3). Although the drying process resulted in a 28.45 % reduction in glucomannans, the research primarily focused on flavour. GC-O (Olfactometry) analysis with 13 panellists indicated nine aroma compounds were aroma-active in dried stems (including 1-octen-3-one and 4-oxoisophorone)(Chapter 4). Carotenoids, amino acids, and monosaccharides were quantified using three Liquid Chromatography techniques, linking precursor loss during drying to aroma-active compound formation (Chapter 5). Shelf life testing indicated no significant changes in aroma-active compounds during storage (20-30 °C for 12 weeks), but higher storage temperatures caused further precursor degradation (Chapter 6). Multivariate analysis indicated aroma compounds as markers of storage and temperature mismanagement. This research provides a mechanistic understanding of flavour generation during Shihu drying, applicable to other plants with similar chemistry. Awareness of important aroma compounds and their changes during storage has the potential to improve product quality and enhance the global popularity of Shihu
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