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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
441

Political attitudes of Hong Kong adolescents towards the PRC: a study of political socialisation.

January 1990 (has links)
by Wan Wai Kwan. / Thesis (M.Phil.)--Chinesse University of Hong Kong, 1990. / Bibliography: leaves 192-196. / Acknowledgments / Chapter Chapter One --- Objective and Literature Review --- p.1 / Chapter Chapter Two --- Methodology and Hypotheses --- p.19 / Chapter A. --- Sampling --- p.19 / Chapter B. --- Hypotheses --- p.25 / Chapter C. --- Analysis --- p.30 / Tables for Chapter Two --- p.33 / Chapter Chapter Three --- A Profile of Two Generations --- p.34 / Chapter A. --- Political attitudes of the adolescents --- p.34 / Chapter B. --- Contrast between parents and adolescents --- p.40 / Chapter C. --- Sex difference and sex-lineage similarity --- p.53 / Tables for Chapter Three --- p.53 / Chapter Chapter Four --- Socialisation in the Family --- p.76 / Tables for Chapter Four --- p.95 / Chapter Chapter Five --- Socialisation in the School --- p.104 / Tables for Chapter Five --- p.120 / Chapter Chapter Six --- Interaction among Agents --- p.126 / Political Knowledge and Political Interest --- p.131 / Tables for Chapter Six --- p.132 / Chapter Chapter Seven --- Conclusion --- p.137 / Notes --- p.153 / Appendixes --- p.152 / Chapter A. --- Tables for demographic data --- p.162 / Chapter B. --- Tables for profile of two generations --- p.164 / Chapter C. --- Tables for socialisation agent - family --- p.166 / Chapter D. --- Tables for socialisation agent - school --- p.169 / Chapter E. --- Tables for conclusion --- p.171 / Chapter F. --- Abbreviation of attitude items --- p.173 / Chapter G. --- Frequency table for the overall sample --- p.174 / Bibliography --- p.192 / Chapter A. --- Books --- p.192 / Chapter B. --- Journals --- p.194 / Questionnaire
442

Abundance and distribution of Microtermes (Isoptera: Termitidae: Macrotermitinae) in cultivated and uncultivated areas at Mokwa in the Southern Guinea savanna vegetation zone of Nigeria

Black, Helaina I. J. January 1994 (has links)
Population dynamics of Microtermes (Isoptera; Macrotermitinae) are investigated in the Southern Guinea savanna vegetation zone of Nigeria. Study sites were primary woodland, long-term maize and a randomised block experiment established from secondary woodland with woodland, pasture, sweet potato, groundnuts, yam and maize. The species assemblage Comprised of Microtermes allleo, Microtermes n.sp. c., Microtermes grassei, Microtermes/epidus, Microtermes subhyalinus. 2 Microtermes abundance and distribution (n/m2) to a soil depth of 1 metre are examined in Chapter Four. Community structure differed with vegetation cover. Abundance was generally higher in the wet compared to the dry season and abundance.was greatest in long-term maize and higher in newly cleared and cultivated sites than in woodland. M subhya/inus was the most abundant species in all vegetation types except long-term cultivated maize where M /epidus was the most abundant species. Changes in crop alter species abundance and Microtermes community structure. Microtermes fungus comb abundance (n/m2), individual dry weight (g) and total dry weight (g/m2) to a soil depth of 1 metre in primary and secondary woodland and short and long-term maize are examined in Chapter Five. Vegetation cover had an influence on seasonal changes in the abundance, individual and total dry weights of fungus combs. M subhyalinus fungus combs showed the greatest seasonal changes, in secondary woodland and short-term maize. Microtermes foraging activity on softwood baits with season, species and vegetation is examined in Chapter Six. Seasonal differences in foraging activity were recorded but differences over time were more significant. Foraging activity differed with vegetation and species. Percentage of baits attacked by species as a proportion of the total number of baits attacked by all species was the best indicator of foraging activity. Non-random foraging was identified for Microtermes with positive associations among M. subhya/inus, M. aluco and M. lepidus. Microtermes foraging activity on baits is compared with soil abundance in Chapter Seven using diversity indices and simple linear regression analysis. Foraging activity can give a more accurate indication of species richness than soil sampling. Foraging activity can be correlated positively with soil abundance, most significantly with wet season assessments.
443

Voice but no exit: the role of loyalty in the political participation of young middle class in Hong Kong.

January 2006 (has links)
Chan Chun Kit. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 248-255). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.v / Content --- p.vi / List of Charts and Tables --- p.xii / Chapter Chapter 1 --- Introduction: The Change of Attitude --- p.1 / Chapter 1.1 --- Research Background and Research Question --- p.1 / Chapter 1.2 --- Theoretical Framework --- p.3 / Chapter 1.3 --- Research Significance --- p.4 / Chapter 1.4 --- Plan of the Thesis --- p.7 / Chapter Chapter 2 --- Literature Review: Concerning Political Participation and Emigration --- p.9 / Chapter 2.1 --- Introduction --- p.9 / Chapter 2.2 --- Emigration --- p.10 / Chapter 2.2.1 --- Literature of Emigration --- p.10 / Chapter 2.2.2 --- Emigration in Hong Kong --- p.11 / Chapter 2.2.3 --- Lesson from the Emigration Literature --- p.15 / Chapter 2.3 --- Political Participation --- p.16 / Chapter 2.3.1 --- Meaning of Political Participation --- p.16 / Chapter 2.3.2 --- The Culturalist Theory --- p.19 / Chapter 2.3.3 --- Political Participation in Hong Kong --- p.22 / Chapter 2.3.4 --- Limitations of Culturalist Theory --- p.25 / Chapter 2.4 --- An Alternative Approach: Hirschman's theory --- p.27 / Chapter 2.4.1 --- Introduction to Hirschman's Theory --- p.28 / Chapter 2.4.2 --- Relationship between Exit and Voice --- p.29 / Chapter 2.4.3 --- The Idea of Loyalty --- p.30 / Chapter 2.4.4 --- Amendment and Critiques of Hirschman's Original Theory --- p.32 / Chapter 2.4.5 --- Other Literatures of Loyalty and Loyalty in Hong Kong --- p.39 / Chapter 2.4.6 --- The Different Role of Loyalty between Hirschman´ةs Literature and Cultualist Theory --- p.41 / Chapter 2.5 --- Conclusion --- p.42 / Chapter Chapter 3 --- Historical Review: Acting between Exit and Voice --- p.44 / Chapter 3.1 --- Introduction --- p.44 / Chapter 3.2 --- Push Factors --- p.45 / Chapter 3.2.1 --- Political Situation before 1997 --- p.45 / Chapter 3.2.2 --- Economic Situation before 1997 --- p.47 / Chapter 3.2.3 --- Political Situation after 1997 --- p.49 / Chapter 3.2.4 --- Economic Situation after 1997 --- p.52 / Chapter 3.2.5 --- The Overall Perception of Hong Kong Future --- p.57 / Chapter 3.3 --- Pull Factors --- p.59 / Chapter 3.3.1 --- The Difficulty for Applying a Foreign Residency --- p.60 / Chapter 3.3.2 --- Economic Situation before 1997 --- p.63 / Chapter 3.3.3 --- Economic Situation after 1997 --- p.65 / Chapter 3.4 --- Pattern of Political Participation and Emigration --- p.73 / Chapter 3.4.1 --- Pattern of Political Participation and Emigration before 1997 --- p.73 / Chapter 3.4.2 --- Pattern of Political Participation and Emigration after 1997 --- p.75 / Chapter 3.5 --- The Puzzle --- p.79 / Chapter 3.6 --- Conclusion --- p.81 / Chapter Chapter 4 --- Theory and Method: Accessing Loyalty --- p.83 / Chapter 4.1 --- Introduction --- p.83 / Chapter 4.2 --- Research Aim --- p.83 / Chapter 4.3 --- Putting Emigration into the Spectrum of Political Participation --- p.84 / Chapter 4.4 --- Subject of Study --- p.86 / Chapter 4.4.1 --- Middle Class Individuals as Quality Conscious Consumer --- p.86 / Chapter 4.4.2 --- The Definition of Middle Class --- p.88 / Chapter 4.5 --- Conceptualizing and Operationalizing Loyalty --- p.90 / Chapter 4.6 --- The Effects of Loyalty --- p.92 / Chapter 4.7 --- Research Approach --- p.95 / Chapter 4.7.1 --- Research Method - Qualitative Data Analysis --- p.95 / Chapter 4.7.2 --- Scope of Sample - Deviant Critical Case --- p.96 / Chapter 4.7.3 --- Sampling Method - Theoretical Sampling --- p.97 / Chapter 4.8 --- Conducting Interviews --- p.99 / Chapter 4.9 --- Data Analysis --- p.100 / Chapter 4.10 --- Conclusion --- p.101 / Chapter Chapter 5 --- Findings and Analysis I: Foundation of the Research: Perception after 97 --- p.103 / Chapter 5.1 --- Introduction --- p.103 / Chapter 5.2 --- Perception about the 1997-2003 Period --- p.103 / Chapter 5.3 --- Deteriorated Areas --- p.105 / Chapter 5.3.1 --- Government Performance --- p.105 / Chapter 5.3.2 --- Political Atmosphere --- p.107 / Chapter 5.3.3 --- Economic Atmosphere --- p.108 / Chapter 5.4 --- The Most Concerned Areas in Past Decades --- p.109 / Chapter 5.4.1 --- Liberty --- p.109 / Chapter 5.4.2 --- Rule of Law --- p.110 / Chapter 5.4.3 --- "The Implementation of ""One Country, Two System" --- p.113 / Chapter 5.5 --- The Perception of Democracy --- p.117 / Chapter 5.6 --- Most Recognized Issues --- p.120 / Chapter 5.6 --- Accessing the Research Question --- p.122 / Chapter 5.7 --- Conclusion --- p.122 / Chapter Chapter 6 --- Findings and Analysis II: Foundation of the Research: Loyalty: Emergence and level of Loyalty --- p.124 / Chapter 6.1 --- Introduction --- p.124 / Chapter 6.2 --- Loyalty to Hong Kong --- p.124 / Chapter 6.2.1 --- Hong Kong Loyalist --- p.125 / Chapter 6.2.2 --- Loyal Complainer of Hong Kong --- p.127 / Chapter 6.2.3 --- The Share Characteristic of “Hong Kong Loyalist´ح and “Loyal Complainer of Hong Kong´ح --- p.130 / Chapter 6.2.4 --- Hong Kong Disloyalist --- p.132 / Chapter 6.3 --- Common Belief ´ؤ The Idea of Liberty --- p.132 / Chapter 6.4 --- Loyalty to China --- p.133 / Chapter 6.4.1 --- China Loyalist --- p.134 / Chapter 6.4.2 --- Separated China Loyalist --- p.136 / Chapter 6.4.3 --- Loyal Complainer of China --- p.139 / Chapter 6.4.4 --- China Disloyalist --- p.141 / Chapter 6.5 --- Common Belief- Psychological Distance --- p.142 / Chapter 6.6 --- Sense of Influent Ability --- p.143 / Chapter 6.6.1 --- Contribution to Hong Kong --- p.144 / Chapter 6.6.2 --- Contribution to China --- p.146 / Chapter 6.6.3 --- Affecting Government's policy --- p.149 / Chapter 6.7 --- Expectation about Future --- p.151 / Chapter 6.8 --- Accessing the Research Question --- p.153 / Chapter 6.9 --- Conclusion --- p.154 / Chapter Chapter 7 --- Findings and Analysis III: Relationship between Loyalty and the July-First Demonstration --- p.157 / Chapter 7.1 --- Introduction --- p.157 / Chapter 7.2 --- Reasons for Joining The Demonstration --- p.157 / Chapter 7.2.1 --- The Dominating Reason --- p.158 / Chapter 7.2.2 --- The Sense of Hongkongese --- p.161 / Chapter 7.2.3 --- Loyalty of Other Organization --- p.163 / Chapter 7.2.3 --- Misunderstanding --- p.164 / Chapter 7.3 --- The Effect of Loyalty in the July-first Demonstration --- p.165 / Chapter 7.4 --- Other Effects of the Demonstration --- p.170 / Chapter 7.5 --- The Post July-first Era and Further Political Participations --- p.172 / Chapter 7.5.1 --- Political Situation --- p.172 / Chapter 7.5.2 --- Economic and Social Situations --- p.175 / Chapter 7.5.3 --- Satisfaction --- p.175 / Chapter 7.5.4 --- Further Political Actions --- p.177 / Chapter 7.6 --- Factor(s) for Simulating Further Demonstrations --- p.179 / Chapter 7.7 --- Discussion --- p.180 / Chapter 7.7.1 --- Loyalty and Demonstration in Hong Kong --- p.180 / Chapter 8.7.2 --- Liberty and Demonstration in Hong Kong --- p.182 / Chapter 8.7.3 --- The level of Satisfaction and the Effectiveness of Demonstration in Hong Kong --- p.184 / Chapter 7.8 --- Conclusion --- p.185 / Chapter Chapter 8 --- Findings and Analysis IV: Relationship between Loyalty and Emigration --- p.187 / Chapter 8.1 --- Introduction --- p.187 / Chapter 8.2 --- Emigration --- p.187 / Chapter 8.2.1 --- Intention of Leaving Hong Kong --- p.188 / Chapter 8.2.2 --- Reasons for Staying --- p.189 / Chapter 8.3 --- Intention of Settlement in China --- p.192 / Chapter 8.3.1 --- Reason of Having the Intention --- p.193 / Chapter 8.3.2 --- Reasons for Staying --- p.193 / Chapter 8.4 --- Cause of Reluctant Emigration --- p.196 / Chapter 8.5 --- The Effect of Loyalty in Emigration --- p.197 / Chapter 8.6 --- Discussion --- p.201 / Chapter 8.6.1 --- Loyalty and Emigration in Hong Kong --- p.201 / Chapter 8.6.2 --- The Effect of the Loyalty of China --- p.203 / Chapter 8.6.3 --- The Credibility of the Threat of Exit --- p.204 / Chapter 8.7 --- Conclusion --- p.205 / Chapter Chapter 9 --- "Conclusion: Re-visiting Exit, Voice and Loyalty" --- p.207 / Chapter 9.1 --- Introduction --- p.207 / Chapter 9.2 --- Summary of the Findings from the Study --- p.208 / Chapter 9.2.1 --- Perception about the Post-97 Situation of Hong Kong --- p.208 / Chapter 9.2.2 --- The Sense of Loyalty --- p.208 / Chapter 9.2.3 --- Relationship between Loyalty and Demonstration --- p.209 / Chapter 9.2.4 --- Relationship between Loyalty and Emigration --- p.210 / Chapter 9.3 --- Discussion of Hirschman's Theory --- p.211 / Chapter 9.3.1 --- Signal Product V.S. Multi-products --- p.211 / Chapter 9.3.2 --- Effects of Loyalty --- p.213 / Chapter 9.3.3 --- Single Loyalty V.S. Multi-loyalties --- p.214 / Chapter 9.3.4 --- "The Tension between Loyalty, Exit and Voice" --- p.216 / Chapter 9.4 --- The Trend of Future --- p.217 / Chapter 9.5 --- Political Implications --- p.219 / Chapter 9.5.1 --- Soft Authoritarianism and Administrative Absorption of Politics --- p.219 / Chapter 9.5.2 --- Liberty cannot be Infringed --- p.221 / Chapter 9.5.3 --- Lack of Strong Demand for Immediate Democratization --- p.221 / Chapter 9.5.4 --- Articulation of Public Opinion --- p.223 / Chapter 9.6 --- Research Limitations --- p.223 / Chapter 9.7 --- Suggestions for Further Researches --- p.225 / Chapter 9.8 --- Conclusion --- p.227 / Appendix --- p.229 / Appendix I Immigrate to Canada: Immigrating to Canada as a Skilled Worker --- p.229 / Appendix II Immigrate to Australia: General skilled migration program --- p.235 / Appendix III Immigrate to United States of America: Apply for Immigrant Status Based on Employment --- p.239 / Appendix IV Interview Schedule (Abridged) --- p.244 / Appendix V Demographic Information of Interviewees --- p.247 / Bibliography --- p.248
444

Programs to promote physical activity among children and adolescents : a case study of the Team Bath Tribe Project

Koorts, Harriet January 2012 (has links)
Background: Physical inactivity has been identified as the fourth leading risk factor for global mortality. Despite public health guidelines advising children and adolescents to spend a minimum of 60 minutes per day of at least moderate intensity physical activity, a large proportion of children and adolescents fail to meet these guidelines. Interventions promoting physical activity show varying degrees of success, and more detailed evaluations of such interventions are essential. The aim of this research was to conduct an in-depth evaluation of a community-based physical activity program aimed at children and adolescents, specifically the Tribe Project. Methods: The RE-AIM framework (Reach, Effectiveness, Adoption, Implementation and Maintenance) was used to evaluate the individual and organisational-level impact of the Tribe Project. A single mixed method case study was used based on five sources of evidence: interviews, questionnaires, documentation, archival records and direct observations. Participants included the Tribe managers and coaches implementing the program and the Tribe parents and children/adolescents who attended. Results: The Tribe Project reached approximately 2.5% of the eligible population living within Bath and North East Somerset. The program successfully met some of its objectives although feedback procedures were poor and the program aims were unclear. The community-level adoption of the program was high, however, the implementation and adherence to the program principles at the setting-level varied. The program was successfully institutionalised within the University of Bath yet pathways after the program into the community varied, and were mostly competitive only. Nonetheless, a combination of social, psychological and physical benefits was reported following participation. Conclusion: To assess accurately the potential impact of physical activity interventions a combined assessment of individual and organisational-level factors is necessary. This will help inform policy on effective strategies to promote physical activity in the community, and develop interventions that are more effective as a result.
445

The Influence of Perceived Support From Parental and Peer Relationships on Students' Health-related Beliefs and Behaviors

Barton, Mitch 05 1900 (has links)
College is an important time for young adults, but most college students fail to meet the daily recommendations for physical activity. Social support is associated with positive health practices, but limited research is available on the role of perceived support from specific relationships, (e.g., peers and parents). The purpose of this study was to evaluate the effect of perceived support from parental and peer relationships on health-related beliefs and behaviors. Participants (N = 333) completed the Quality of Relationships Inventory, Multidimensional Scale of Perceived Social Support, Satisfaction With Life scale, and a short version of the Physical Self-Description Questionnaire. While highly active students did not necessarily have more socially support relationships, females self-reported more conflict with both parents and more depth and support with a special person in their life than males, and parental and peer relationships appeared to be a greater influence on females' perceptions of satisfaction and self-worth.
446

Reliability and Validity of the FITNESSGRAM® Physical Activity Items

San Miguel, Kaleigh 08 1900 (has links)
Large-scale assessments of children and youth physical activity (PA) behaviors are regularly conducted in school settings. In addition to assessing actual fitness, the FITNESSGRAM® assesses self-reported PA behaviors for aerobic, strengthening, and flexibility activity within the past 7 days. The purpose of this study was to examine the reliability and validity of the three PA items. Participants included 1010 students in grades three through twelve and were either tested under a teacher – teacher condition, an expert - expert condition, a teacher – expert condition, or a trained teacher – expert condition. Comparisons of the responses to the PA items indicated adequate reliability for teachers, but the reliability improved with training. Likewise, the validities for teachers are moderate to fair; however, they improved when teachers received additional training.
447

Using evolutionary theory to support lifestyle change and improve health in people at risk of developing chronic diseases

Grey, Elisabeth January 2018 (has links)
This research sought to develop and test a health behaviour change intervention for overweight and inactive UK adults, aged 35-74 years, using the concept of an evolutionary mismatch to frame health information. The mismatch concept posits that human culture has evolved too rapidly for biological evolution to keep up, meaning the human body is poorly adapted to cope with the modern environment, predisposing us to chronic disorders. The first study explored whether using the mismatch concept to frame health information would be acceptable and engaging to target users. Mismatch-based text and graphic resources were shown to participants in semi-structured interviews. They had good acceptability, generated interest and seemed to provide a meaningful rationale for behaviour change. Following further development, the second study tested whether the resources could improve people's understanding of the effects of physical activity and diet on health and bring about change in theory-based cognitive determinants of behaviour. This questionnaire-based study found the resources enhanced knowledge and effected positive changes in most of the targeted cognitions. The mismatch resources were then developed into an online intervention also incorporating evidence-based behaviour change techniques. The third study evaluated this intervention in a pilot randomised controlled trial. The intervention did not lead to significantly greater improvement in physical activity or diet than a minimal intervention comparison, however the behavioural and health changes achieved in the intervention group were of meaningful effect size. Process evaluation provided partial support for hypothesised mechanisms of behaviour change. The findings suggest the mismatch concept could be a useful frame to stimulate initial interest and motivation in health interventions; combined with additional behavioural techniques this can help promote healthy lifestyle change. Further work is needed to test the efficacy of a mismatch-framed intervention among populations of different ages, ethnicities and religious beliefs.
448

A study of the significance of galvanic skin resistance in relationship to performance of girls in varsity field hockey games

Moulton, Jane January 1957 (has links)
Thesis (M.A.)--Boston University
449

The electrophysiological correlates of maths anxiety : exploring the role of gamma activity

Batashvili, Michael January 2016 (has links)
This thesis set out to investigate the electrophysiological correlates of maths anxiety (MA). Research has shown that those with high MA (HMA) tend to have poorer accuracy and increased reaction time on maths based tasks and that high maths anxious individuals avoid situations where they might have to use maths. This can impact on their future by restricting their degree or job prospects. Previous research has identified the behavioural cognitive and psychological effects of MA and recently studies have begun to examine the associated underlying mechanisms in the brain. Chapter one outlines the background MA behavioural and measurement research before evaluating the neurophysiological methods used in cognitive neuroscience and the use of electroencephalography (EEG) in chapter two. Chapter three continues by outlining previous research concerning the neurophysiological processing of maths and number before evaluating relevant neurophysiological research concerning MA. Four experimental studies are conducted, exploring the neurophysiological underpinnings of MA research using EEG. Each of these recruits 30 participants and measures of electro-cortical (Event Related Potentials (ERPs), Global Field Power, Frequency etc.) and questionnaire measures are implemented. The first study aimed to identify whether the behavioural effects of MA (poorer accuracy and increased reaction time) are consistent with ERP differences (component amplitude and latency differences) in the brain and to understand why these effects are experienced. This revealed no significant comparisons between ERP components and behavioural responses involving low and high maths anxious individuals, but this may have been due to the lack of an anxious response by using a verification task, rather than requiring calculation. Study two introduces the measurement of gamma activity as a neurophysiological measure of anxiety and threat processing and brings three core areas of anxiety research together: Previous studies outline high anxiety in connection with gamma modulation, also showing gamma band activity is associated with the amygdala and finally, that the amygdala is responsible for the processing of threat perception and anxiety. This research has not been brought together when studying MA. Results produced similar ERP findings to the previous study but the introduction of gamma activity into the research provided the first differences between high and low MA (LMA) groups, showing significantly greater gamma activity levels in HMA individuals. However, this study only used numerically-based tasks, thus the third study implemented a non-numerical condition to act as a control. Study three replicates the findings showing a reduced level of gamma activity in high MA individuals for the non-numerical based task, however, this was also reduced for the simple maths task. It was theorised that it is more likely to be the initial threat perception that represents the anxious response and gamma activity increases. To test this and remove any working memory demands, the fourth study implements the presentation of single digit observation (using single digit numbers and letters). Even though there was no demand on working memory, high maths anxious participants displayed similar levels of gamma activity as low maths anxious individuals during letter observation. However, they had significantly greater levels during the observation of number. Findings suggest that HMA individuals may not only struggle with the processing of maths stimuli, but may have a threat-related response to the simple observation of numerical stimuli. This implies that HMA individuals consistently apply an avoidance technique due to a threat response associated with increased levels of gamma activity. The findings of the each study are finally discussed in terms of their contribution to the neurophysiological underpinnings of MA, the first exploration of this using gamma activity, future research and the extent that number anxiety may act as a precursor or sine qua non to MA.
450

The role of integrins in the activation of fibroblasts from skin, lung and breast tissue

Khan, Zareen A. January 2017 (has links)
Fibroblasts are abundant mesenchymal cells present in all tissues in a quiescent state, which contribute to wound healing when activated. Cytokine transforming growth factor-β1 (TGF-β1) stimulates fibroblast-myofibroblast differentiation, which induces extracellular matrix secretion, tissue contraction and promotes cancer cell migration. Hence, chronic activity of stromal myofibroblasts correlates with a poor prognosis for cancer and organ fibrosis patients. Therefore, modulating myofibroblast activity may reduce the severity of these diseases. Previous research suggests blockade of transmembrane integrin receptors expressed by fibroblasts prevents TGF-β1- induced differentiation, indicating integrins are attractive therapeutic targets. However, fibroblasts derived from different organs exhibit heterogeneity, although their integrin expression and integrin-regulated differentiation has not been directly compared. The aim of my research was 1) to understand and compare how integrins regulate TGF-β1-induced activation of fibroblasts derived from normal skin, lung and breast tissue; 2) to examine the global gene expression of TGF-β1-treated lung fibroblasts; 3) to identify novel therapeutic targets that modulate TGF-β1-induced activation of lung fibroblasts using a drug library. qPCR showed skin, lung and breast fibroblasts differentially expressed TGF-β1- induced activation markers, including ACTA2, FN1, TIMP3, CTGF and SERPINE1, in addition to integrin genes for α1, α4, α11 and β3. Small-molecule inhibitors of αv integrins only reduced the invasion of TGF-β1-exposed skin fibroblasts, but not lung or breast fibroblasts. siRNA against α11, β3 and β5 decreased TGF-β1-induced collagen contraction and activation marker expression in skin and lung fibroblasts, while α1 siRNA prevented collagen contraction by breast fibroblasts only. RNA sequencing of TGF-β1-treated lung fibroblasts revealed pro-inflammatory and profibrotic pathways were significantly enriched, while screening TGF-β1-treated lung fibroblasts with a FDA-approved drug library identified 46 hits that significantly reduced α-smooth muscle actin and fibronectin expression. Overall, genes are differentially expressed in TGF-β1-treated skin, lung and breast fibroblasts, while different integrins in each fibroblast appear to regulate invasion, TGF-β1-induced collagen contraction and gene expression. RNA sequencing revealed TGF-β1 promotes the expression of a pro-tumour signature in lung fibroblasts and several novel therapeutic targets that modulate the activation of lung fibroblasts have been identified. Understanding these integrin-dependent and independent mechanisms will facilitate the generation of myofibroblast-targeted treatments for cancer and organ fibrosis.

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