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Daniels, Melissa Lynn. "Minimizing Visitor Impacts to Protected Lands: An Examination of Site Management and Visitor Education Methods". Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/42509.
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This thesis contains two studies that explore different methods of visitor management in recreation. The management strategies studied here are both relatively indirect approaches intended to minimize the environmental and social impacts that visitors cause in protected areas. The Annapolis Rocks study focuses on visitors' evaluations of a site management strategy that shifted camping from a flat, open area to constructed side-hill campsites. A visitor questionnaire was administered before and after the treatment to determine visitors' ratings of importance and satisfaction for various campsite attributes. We found some evidence of visitor displacement but concluded that the site management strategy supported the intentions of the managers. The Leave No Trace study evaluates the effectiveness of the Trainer courses in improving the knowledge, ethics, and behavior of the participants and encouraging them to teach others in the community. This study employed pre-course, post-course, and follow-up questionnaires to evaluate the participants' short-term and long-term gains from the course. Trainer course participants showed significant short-term and long-term gains from the course, with a slight decline in the total gain four months after the course. The participants showed improvements in low-impact behaviors, suggesting that education is an effective visitor management strategy. These studies demonstrate that managers can be successful at controlling visitor impacts without relying on stringent regulations and enforcement.Master of Science
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Reid, Scott Edmonds. "An Adaptive Assessment of Visitor Impacts to Protected Areas". Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/32365.
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As an applied approach to recreation management, adaptive management allows researchers and protected area managers to cooperatively improve management policies, and achieve the dual mandate to protect natural resources and provide high-quality recreational experiences. Through an evaluation of the efficacy of campsite and campfire management policies, this research provides land managers with an empirical assessment to aid in the adaptation and improvement of their visitor management strategies. Results from the Shenandoah National Park camping management study suggest that an established camping visitor containment strategy succeeded in reducing the areal extent of camping impacts while minimizing restrictions on visitor campsite selection options. Findings from the campfire research in seven protected areas indicate that current campfire policies have been largely ineffectual at reducing resource damage, and may exact a heavy toll in visitor experiences via campfire restrictions. The incorporation of resource and social research in this research offers a holistic approach to the evaluation of management objectives and affords protected area managers a more balanced perspective on the assessment of their policies. The conclusions reached by this integrated research will provide land managers with germane and timely information that will allow them to adapt their policies to better achieve their recreation management objectives.Master of Science
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Turner, Rex. "Visitor Behaviors and Resource Impacts at Cadillac Mountain, Acadia National Park". Fogler Library, University of Maine, 2001. http://www.library.umaine.edu/theses/pdf/TurnerR2001.pdf.
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Littlefair, Carolyn Joy, i n/a. "The Effectiveness of Interpretation in Reducing the Impacts of Visitors in National Parks". Griffith University. School of Environmental and Applied Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050324.085357.
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With visitation to natural areas increasing, the appropriate management of these areas is important. There are a number of management tools available which endeavour to minimise environmental impacts of visitors. One such management tool is interpretation. Interpretation is widely used as a management tool because: it is perceived to be the most cost effective method; it is a light-handed approach and allows visitors the freedom of choice; and it enhances visitor experiences and satisfaction. However, the ability of interpretation to bring about a reduction in the impacts of visitors to natural areas, has rarely been quantified. This study was designed to determine the extent to which an interpretive program reduced the environmental impacts of visitors to national parks. Fieldwork was undertaken in Lamington National Park, where 41 guided walks were examined. To measure the actual behaviour or resulting impacts of visitors in a national park, three appropriate environmental indicators were chosen: shortcutting of corners, picking up litter already on the track, and noise levels. Five interpretive programs were created, each with a different combination of environmental interpretation, role modelling and verbal appeals. For the shortcutting results, the interpretive program with the combination of environmental interpretation, role modelling by the guide and verbal appeals from the guide, was always the most effective in reducing shortcutting. Visitors in this interpretive program were always, statistically, less likely to shortcut than visitors on all the other interpretive programs. The programs with only environmental interpretation or no environmental interpretation, were always least effective in reducing shortcutting. The interpretive programs with environment interpretation plus role modelling, or verbal appeals, were always in the middle of these extremes. They were more effective than having neither role modelling or verbal appeals, but less effective than having both. Results for the amount of litter picked up found that the inclusion of verbal appeals in an interpretive program was the only factor that influenced whether visitors picked up litter. In addition, there was no difference in the amount of litter picked up, by the interpretive program with environmental interpretation only, and the program with no environmental interpretation. Results for the noise levels of visitors, found that no interpretive program reduced the amount of shouting and talking loudly of visitors. Although not statistically significant, it did appear that there were lower proportions of shouting and talking loudly, following a verbal appeal and/or role modelling. Additionally, there was no influence of the interpretive program on the proportion of time visitors were talking, or quiet, during their walk. Overall, this research found that interpretation can be an effective management tool in reducing visitor impacts. Interpretation is most effective in reducing impacts when those impacts are specifically addressed through verbal appeals, combined with positive role modelling of appropriate behaviours. However, interpretation did not reduce all the impacts studied and therefore is not the solution to all problems. Implications of this study are that those using interpretation as a means of reducing visitor impacts, must ensure that they have a high standard of interpretation, which specifically addresses the impacts that need to be reduced. It also highlights the importance of the role of the guide, and that those employed should be well trained and competent in their position.
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Wood, Kerry Todd. "Assessing Recreation Impacts to Cliffs in Shenandoah National Park: Integrating Visitor Observation with Trail and Recreation Site Measurements". Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/33032.
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The rock outcrops and cliffs of Shenandoah National Park provide habitat for several rare and endangered plant and animal species. The location of the world-famous ridgeline parkway, Skyline Drive, makes many outcrops and cliffs within the park readily accessible to the parkâ s 1.2 million annual visitors. Consequently, visitor use of cliff areas has led to natural resource impacts, including marked decreases in size and vigor of known rare plant populations.
Despite the clear ecological value and potential threats to the natural resources at cliff areas in the park, managers possess little information on visitor use of cliff sites and presently have no formal planning document to guide management. Thus, a park wide study of cliff sites was initiated during the 2005 visitor use season. As part of this research effort, the study presented in this thesis integrated data from resource impact measurements and visitor use observation to help assess the effects of recreational use on the natural resources of one heavily used cliff site in the park, Little Stony Man Cliffs.
Results of resource impact measurements indicate that several nodal areas of high disturbance (bare soil) are present on the cliff-top and cliff-bottom. Additionally, visitor observation data point to several possible visitor use factors that may contribute to cliff-top impacts, including concentrated levels of use during certain times of day and days of the week, and frequent trampling of soil and vegetation by visitors. The information from the study presented in this thesis will help assist Shenandoah National Park staff in developing a cliff resource management plan that will protect park resources while providing opportunities for visitor enjoyment.Master of Science
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Farrell, Tracy Ann. "Visitor Impact Assessment and Management for Protected Areas in Central and South America". Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/40425.
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Ecotourism and protected area visitation have been steadily increasing in recent years in Central and South America, inevitably resulting in natural resource impacts. The consequences of such impacts may include natural resource degradation, diminished aesthetic qualities, or decreased functionality of certain facilities like recreation sites and trails. Recreation ecology and visitor impact management expertise and tools are available to help balance the potentially conflicting management goals of protecting natural resources and permitting visitation but such knowledge has not been widely used in Central and South America.
The goals of this research were to characterize certain visitor-related natural resource impacts and to determine how these impacts could be assessed and managed in Central and South America. The research included case studies of eight protected areas in Costa Rica and Belize, trail impact assessment research at Torres del Paine National Park in Chile, and development of a new visitor impact assessment and management framework, presented as three papers intended for journal submission.
The first paper had two objectives: 1) to identify visitor-related natural resource impacts at selected protected areas in Costa Rica and Belize to increase awareness about visitor impact problems, and 2) to apply and compare rapid trail and recreation site impact assessment procedures to provide study site managers with impact data and impact assessment procedures. A variety of natural resource impacts were reported by interview subjects and recorded by rapid assessment procedures. The management utility of the rapid trail and recreation site impact assessment procedures were compared and discussed and the need for developing additional rapid assessment procedures to evaluate other resource impacts reported by protected area managers was also identified.
The intent of the second paper was to investigate trail impacts at Torres del Paine National Park. Study objectives included measuring the frequency and magnitude of selected trail impacts, and comparing the relative impact contribution of the amount of use, vegetation type, trail position and trail grade on common condition indicators such as width and incision. Findings somewhat contradicted those of other studies, revealing that amount of use significantly contributed to trail width and incision. However, findings also indicated that vegetation type and trail grade contributed to number of informal trails and trail incision, respectively. A variety of management strategies were recommended and suggestions were provided for future monitoring studies.
The purpose of the third paper was to propose a new visitor impact assessment and management framework that would provide managers with a feasible means of addressing visitor impact management concerns for selected protected areas in Central and South America. The Protected Areas Impact Assessment and Management (PAIAM) framework was adapted from existing frameworks like carrying capacity and the Limits of Acceptable Change to provide a simple, cost-effective and relatively quick decision making process. PAIAM analyzes visitor impacts using an expert panel and incorporates stakeholders and local residents into decision making. This study experimentally applied the new framework in Mexico and compared PAIAM to existing frameworks.
The focus of this dissertation is on Central and South America since they are heavily visited ecotourist regions that could potentially benefit from applying recreation ecology and visitor impact expertise and tools to protected area management. This research demonstrated that a variety of visitor impacts are affecting natural resources and visitor facilities like trails and recreation sites at selected protected areas in Central and South America. This research also developed and applied rapid impact assessment procedures and visitor impact frameworks for use in Central and South American protected areas.Ph. D.
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RAMTAHAL, JOEL FABIAN. "CAMPSITE IMPACTS IN WILDERNESS VS. VISITOR WILLINGNESS TO PAY FOR ITS PRESERVATION". OpenSIUC, 2012. https://opensiuc.lib.siu.edu/theses/817.
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Wilderness areas provide a wide array of quality nature experiences including primitive recreational opportunities in a primeval condition. However, a lot of these ecological and pristine sites suffer from disturbance and environmental degradation by the exhaustive human recreational use on campsites. Most of the impacts associated with camping gradually become a critical concern since they can be devastating to a wilderness environment and the affiliated experience. This study employed the contingent valuation method to determine peoples' willingness to pay for the preservation of the Panther Den Wilderness if campsites were restricted /limited, and to estimate an economic value of non-market goods and services affiliated to the preservation and use values of the Panther Den Wilderness. A Contingent valuation questionnaire was administered to gather information on the respondent's intentions and to determine what they would be willing to pay under a hypothetical scenario. Moon's WTP model estimated the willingness to pay relationship with a set of explanatory and socio-demographic variables including bid sizes, miles traveled, recreation times, campsite impacts observed, age, gender, and education. Results revealed that there was a clear relationship between the respondents' willingness to pay, the pre-determined bid-size/fee level, and the distance traveled to the Panther Den Wilderness, hence; the correlation between the variables was highly significant. The estimated mean willingness to pay value for the preservation of the Panther Den Wilderness was $9.56 per visitor. Overall, the estimated results and mean willingness to pay value served as the interpretation of an assessment which clearly revealed that outdoor recreation users were willing to pay a user fee for the preservation of the Panther Den Wilderness regardless of campsite limitations or restrictions.
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Leujak, Wera. "Monitoring of coral communities in South Sinai, Egypt, with reference to visitor impacts". Thesis, University of London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430866.
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Lee, Nathaniel H. "Environmental Impacts of Camping in Low Regulatory Wilderness: Geographic Patterns in the Allegheny National Forest and their Implications for Management". Kent State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=kent1523442960070504.
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Squires, Carolyn. "An Assessment of Trampling Impact on Alpine Vegetation, Fiordland and Mount Aspiring National Parks, New Zealand". Thesis, University of Canterbury. Environmental Science, 2007. http://hdl.handle.net/10092/1494.
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The objectives of this study were two fold. The first was to quantify the nature and extent of current levels of human impact in alpine areas at four sites within Fiordland and Mount Aspiring National Parks along walking tracks at Key Summit, Gertrude Saddle, Borland Saddle and Sugarloaf Pass. In order to do so, a survey was carried out with transects placed perpendicular to the track, and distributed among different vegetation types. In each transect, plant structural and compositional aspects, and soil and environmental parameters were measured. Transects were divided into track, transition, undisturbed and control zones, and changes to dependent variables were compared with distance from the track centre. Damage from visitor impact was largely restricted to within 1m from the track centre. The most significant impacts were to structural aspects of plant and soil properties with significant reductions in plant height, total vegetation cover and bryophyte cover, and increases in bareground and erosion on tracks. Erosion was more prevalent on slopes greater than 25°, while tracks on peat soils contained greater bareground exposure, particularly of organic soil. The second study objective was to investigate the relationship between specific levels of impact and the resulting damage to two key alpine vegetation types, tussock herb field and cushion bog. This was undertaken by carrying out controlled trampling experiments, measuring changes to plant structural and compositional aspects four weeks and one year after treatment. Both vegetation types saw dramatic reductions in total vegetation cover and height immediately after trampling, however overall composition and species richness varied little. These two alpine vegetation types showed moderate-low resistance to initial impact and low resilience, with very little recovery evident one year later. Research intothese two areas is important for managing visitor use within alpine areas in order to meet conservation and recreation goals. The survey indicates that alpine community types are very sensitive to visitor use, showing significant structural damage, however the spatial extent of impact is limited within the broader landscape. Instead, visitor impacts associated with tracks are likely to be more visually and aesthetically significant, influencing the visitor experience. The trampling experiments indicate that use levels over 25-75 passes per year within tussock herbfield and cushion bog vegetation on peat soils will result in ongoing damage to previously undisturbed sites. Methods for minimising impacts include limiting visitor numbers, public education in low impact practices, redirection of tracks and use to areas that are less sensitive, the dispersal of visitor activity at very low use intensities (less than 75 direct passes per year) and the concentration of activity on tracks above this level.
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Dawson, Jordan O. "The impacts of mega events : a case study of visitor profiles, practices and perceptions in the Queen Elizabeth Olympic Park, East London". Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/33762.
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In 2012, London successfully hosted the Games of the XXX Olympiad. The main legacy of hosting the event is the 560 acre, mixed use Queen Elizabeth Olympic Park located in Stratford in the heart of London s former industrial East End. The Park is located across the four Park Boroughs of Hackney, Newham, Tower Hamlets and Waltham Forest, each distinct in character but shaped by similar trends of urban regeneration and gentrification. This research examines the profiles, practices and perceptions of visitors to the Queen Elizabeth Olympic Park as an impact study of mega events conducted within five years after the London Olympics. It draws on research about mega events and urban regeneration with a focus on sports science and geography that has largely neglected visitor experiences as an outcome of mega events. Based on a mixed methods approach combining a longitudinal face-to-face visitor survey conducted over two years, a postal survey among local schools, and interviews with stakeholders, this thesis makes an original contribution to knowledge by proposing a new conceptual framework on mega event legacy and empirical findings on the use and perceptions of The Park by local, regional, national and international visitors. The conceptual approach (Chapter 3) bridges the two distinct literatures of mega-event legacy theory (and more broadly the sports literature) and actor-network theory. The framework allows for the study to approach the research questions from a tridic actor-network perspective, examining how material, immaterial and mainly human dynamic hybrids co-exist in complex webs of relations. It also allows for the unravelling of how these relations have given rise to impacts tied to the developments in the Queen Elizabeth Olympic Park. This unravelling is explored through the remainder of this thesis. Following the description and analysis of methods used in the thesis (Chapter 4), Chapter 5 provides a historic overview of the four Park Boroughs that define the study area of the thesis. The shifting nature of this multicultural area is contextualised in light of several catalytic events (industrialisation, de-industrialisation and finally the Olympic Games). At the heart of this examination is the intention to show that despite the narratives pedalled by policy makers, planners and politicians, areas of East London were inhabited by groups who for several centuries symbiotically produced and reproduced their own diverse identities and ultimately that of East London. Chapter 6 analyses and critiques 35 policy documents released during the Olympic cycle (broadly defined here as the period between 2003 and 2012) and follows both the visible and invisible actants. The key findings are that: poorly executed event planning is inextricably linked to a poor implementation of local community interests; there were unheard and excluded voices, particularly the disadvantaged and displaced, in these policy and planning documents and; that there was little opportunity for the youth voice to be heard. Finally, the analysis of policy documents has underlined the value of reflecting on legacy promises from a longer-term perspective, suggesting that the legally binding bid books should be compared with the actual outcomes from a long-term perspective. The typical visitor to the Queen Elizabeth Olympic Park (Chapter 7) is a white middle-aged male or female (71% over age 25, ~50/50 male and female). They will be visiting the sports facilities and their frequency of use suggests that they have monthly membership to one of the leisure centres. This indicates that they have a relatively high level of both social capital and disposable income. They will reside within the Park Boroughs, often within walking distance of the Park or close to a transport link with a direct transport connection, probably by the Underground system. They will not often visit the Park with under 18s and if they do visit with anyone, it will be their partner or friend, and thus they resemble very closely the typical affluent gentrifier couples. The term experience athlete was coined for these visitors with 53% being from the Park Boroughs. In addition, there were those who came to sight-see, designated as Games tourists of whom 56% of these were international visitors. While ~20% of the visitors to the Park were under age 18 most of these were under 12s attending with their parents. Young people and particularly young people from the Park Boroughs were largely absent from the Park, which was contributed to by discriminatory practices (often under the guise of security issues) which focused on groups of ethnic minority youth. The possible reasons for the absence of young people from the Park are explored and unravelled in Chapter 8 by discussing the results of the semi-structured interviews with local stakeholders and the postal survey with school staff. The key issues raised in this chapter were that: the lack of a representative youth voice with a hidden and perceived to be cosmetic contribution to legacy planning and; the lack of social and financial capital in school staff and young people in combination with the gentrifying process and; spatial factors such as distance from the Park and poor acces routes, all contributed to the absence of young people from the Park. Overall, this thesis stresses the importance of unravelling networks to their fullest extent to truly understand the impact such spaces have on diverse communities.
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Lewis, Anna Rose. "Remote camping along the Ningaloo Coast, Western Australia: relationship between management and the variables of visitor preferences, resource use and environmental impacts". Thesis, Curtin University, 2013. http://hdl.handle.net/20.500.11937/2176.
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The aim of this multidisciplinary study was to identify relationships between level of management oversight and the variables of visitor preferences, resource use and environmental impacts at remote coastal campsites along the Ningaloo coast, Western Australia. Significant differences existed for all three variables, determined from four statistically-derived campsite clusters. This thesis demonstrates the importance of management practices to specific types of environmental impact and expands methodological and theoretical knowledge for semi-arid, vehicle accessible environments.
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D'Antonio, Ashley L. "Recreation Resource Impacts in the Bear Lake Road Corridor of Rocky Mountain National Park, Colorado, USA: An Assessment of Resource Conditions and Visitor Perceptions". DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/817.
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Visitor use in parks and protected areas inevitably leads to resource impacts. In order to effectively manage for resource impacts, it is important for managers to not only understand ecological aspects of their system but sociological aspects as well. The two papers presented in this thesis used integrated approaches to better understand the current level of resource impacts within the Bear Lake Road Corridor of Rocky Mountain National Park and to explore visitor perceptions of these impacts. The first paper used traditional monitoring and assessment techniques, as well as recently developed methodologies, to determine the current level of resource impacts and examine areas for potential future resource change. Findings showed that there is significant impact in the trail system, particularly at popular hiking destinations. At two of these popular hiking destinations, with current use levels, there is potential for future resource change. Integration with measures of social norms showed that visitors are frequently experiencing resource conditions within the Bear Lake Road Corridor that are considered unacceptable.
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Britto, Pedro Dultra. "Capacidade de visitação : ensaio metodologico para trilhas em unidade de conservação". [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258660.
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Orientador: Rosely Ferreira dos SantosDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
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Resumo: Estudos sobre capacidade de visitação são necessários para o planejamento e gestão da visitação pública em Unidades de Conservação. O uso destas áreas naturais para visitação pode acarretar impactos indesejados, e o equipamento mais comum utilizado nesta atividade é também o que mais fragiliza o meio conservado: a trilha. As metodologias disponíveis atualmente, e utilizadas para este tipo de avaliação em trilhas de UCs brasileiras, são, normalmente, estrangeiras e extemporâneas. Considerando que isto pode ser uma inadequação para as características bastante diversificadas das UCs brasileiras, quais critérios são válidos para a escolha de uma, ou várias, metodologias de avaliação desta capacidade ou dos impactos advindos da visitação pública? Este estudo aborda várias metodologias, notadamente as três mais utilizadas, sob a perspectiva de uma trilha brasileira que possui intensa visitação pública: A Trilha do Castelinho, localizada no Jardim Botânico de São Paulo, dentro do Parque Estadual Fontes do Ipiranga. Ele também pretende estruturar, a partir da abrangência destas três metodologias, a formulação de uma nova, híbrida, que responda satisfatoriamente a uma realidade brasileira
Abstract: Studies about carrying capacity are necessary for the planning and management for visitor in environment Conservation Areas. Visitor in these areas can cause undesirable impact, and the main apparatus in this activity is the most fragile in the Conservation Area: tracks. The methods available to evaluate this impact in Brazilian Conservation Areas are normally foreign considering that this might be inadequate for the diversity of the Brazilian Conservation Areas, which criterions are valid in the choice of one or more evaluate methods in carrying capacity or visitor? This study analyzes three different methods that are the most used in one tracks that has visitor: The "Trilha do Castelinho" in the São Paulo Botanic Garden , in Fontes do Ipiranga State Park . This study also intend to develop a new method, from these three that correspond to the Brazilian reality
Mestrado
Saneamento e Ambiente
Mestre em Engenharia Civil
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Araujo, Carolina Dutra de. "Perfil do Visitante e Capacidade de Carga Tur?stica em ?reas Protegidas: o caso do Parque Estadual da Ilha Grande, RJ". Universidade Federal Rural do Rio de Janeiro, 2006. https://tede.ufrrj.br/jspui/handle/tede/480.
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Previous issue date: 2006-10-26The objective of this work was to contribute to the study of tourism environmental planning, specifically Tourism Carrying Capacity methodologies. To do this, two methods were compared, Limits of Acceptable Changes (LAC) e Visitor Activities Management Process (VAMP), in relation to the adequacy to the area, identifying the environmental risks and anthrop pressures; and related to the focus on local issues and the visitors profile, in Praia Preta, located in the Parque Estadual da Ilha Grande, Angra dos Reis, RJ. Few differences were observed between the methods, with little advantage to LAC. We suggest that two fundamental components should take part of a Tourism Carrying Capacity framework: the visitors profile and activities and the residents perception related to local tourism. Such information should compose the management strategies in Protected Areas.
O objetivo da pesquisa foi contribuir para o estudo do planejamento ambiental tur?stico, especificamente sobre as metodologias de Capacidade de Carga Tur?stica. Para tanto, foram comparados dois m?todos, Limits of Acceptable Changes (LAC) e Visitor Activities Management Process (VAMP), quanto ? adequa??o ao local, identificando os riscos ambientais e press?es antr?picas; e quanto ? aten??o ?s quest?es locais e perfil do visitante, na Praia Preta, localizada no Parque Estadual da Ilha Grande, Angra dos Reis/RJ. Observaram-se poucas diferen?as entre os m?todos, com algumas vantagens para o LAC. Sugeriram-se que dois componentes fundamentais devem fazer parte de uma metodologia de Capacidade de Carga Tur?stica: a caracteriza??o do perfil e atividades praticadas pelo visitante e a percep??o dos residentes acerca do turismo no local, informa??es que deveriam compor as estrat?gias de manejo em ?reas protegidas.
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Hardiman, Nigel John, University of Western Sydney i of Science Technology and Environment College. "Visitor impact management in canyons of the Blue Mountains, New South Wales". THESIS_CSTE_xxx_Hardiman_N.xml, 2003. http://handle.uws.edu.au:8081/1959.7/9.
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There is concern that canyoning, which has grown in popularity in recent years, may not be environmentally sustainable within the Blue Mountains National Park. Sociomanagerial research was undertaken, using an initial focus group discussion and subsequent surveys. Canyoners were found to participate in their sport predominantly in small groups in relatively few canyons, were generally experienced, did not feel crowded by other people encountered, and displayed little evidence of displacement behaviour from popular locations. No specific biophysical impacts were perceived as serious. Canyoners generally supported management action to control visitation to canyons if overuse could be demonstrated, with education and/or restrictive actions as preferred management strategies. Biophysical research was undertaken to test a potential rapid assessment bioindicator for measuring and monitoring potential visitor impacts. Macroinvertebrate data were analysed and no significant difference in macroinvertebrate assemblage composition or water quality was found between high and low visitation streams. Macroinvertebrate fauna were found to be highly resilient to trampling. Current visitation levels within the canyons appeared to be within ecologiocally sustainable levels. The implications of the findings are discussed for visitor impact management policymaking.Doctor of Philosophy (PhD)
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Chariandy, Celeste Marie-Ange. "The Impact of the NIHERST/NGC National Science Centre, Trinidad and Tobago on Visiting Student Groups". Thesis, Högskolan Dalarna, Vetenskapskommunikation, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:du-1161.
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The aim of this study was to asses the impact of a visit to the NIHERST/NGC National Science Centre in Trinidad on four different school-age visitor groups. The research was conducted through the administering of a post-visit questionnaire immediately upon completion of each visit by each group, and via visitor feedback obtained in post-visit or pre-visit activities conducted within two weeks of the visit for three groups. Teachers/instructors who accompanied the groups on their visit also completed post-visit questionnaires and provided additional information on follow-up activities via an interview. The results of this investigation suggest that the visit to this science centre provided entertainment/enjoyment value and potential educational value to most individuals. The nature of this enjoyment was noted for various age groups and genders in this study. Quantification of the educational impact was not possible within the constraints of this study, which was unable to capture long-term effects of the supply of ‘new knowledge’ to visitors which the visit to the science centre had provided.
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Guthrie, Catherine M. "Sense making and sense giving : using visitor narratives to understand the impact of visitor interactions on destination image". Thesis, Robert Gordon University, 2007. http://hdl.handle.net/10059/179.
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Destination image is acknowledged as a key factor in destination choice and visitor satisfaction. However, despite thirty years’ research from a variety of perspectives into destination image and image formation, the impact of actual visitation has been largely neglected and understanding of the processes involved in that change is therefore limited. Visitor experience is increasingly recognised as being unique to the individual, leading to calls for research strategies taking into account the visitor’s perspective. This study uses a phenomenological approach to investigate visitor-destination interactions, capturing visitors’ lived experience as expressed in their holiday narratives. Applying a double hermeneutic approach to analysing interview data, this study outlines the elements of destination experience and shows how the meaning encapsulated in the individual’s destination image is mediated by his/her stock of knowledge, the particular combination of predispositions, motivations and characteristics, as well as by their in-destination interactions and encounters with people and place. It develops the ideal typifications of Gourmet, Grazer and Gourmand to help explain the complex and dynamic interaction between visitor characteristics and behaviour and extends our understanding of the role of other tourists in destination experience by illuminating tourist-tourist interactions and revealing the compromises necessitated by the presence of other tourists. By generating insight into the complex and dynamic interaction between anticipations, motivations and predispositions, and the way in which this interaction affects the visitor’s experience of people and place in a destination, the study has demonstrated the utility of the phenomenological approach in understanding visitor interactions. It has also resulted in a model which explains the processes whereby the visitor makes sense of his/her experience and transmits that experience to others. This can be used by academics and practitioners to further understand the benefits and attractions of existing destinations and to predict the attraction of potential destinations, as well as to promote greater understanding of tourist-host interactions among destination industry providers.
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Toews, Valerie. "A backcountry visitor impact management strategy for Riding Mountain National Park". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0007/MQ45128.pdf.
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Fletcher, Helen. "The impact and management of visitor pressure on Rocky Shore communities". Thesis, University of Newcastle Upon Tyne, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363528.
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Hardiman, Nigel John. "Visitor impact management in canyons of the Blue Mountains, New South Wales /". View thesis, 2003. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030708.115013/index.html.
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Thesis (Ph.D.) -- University of Western Sydney, 2003."Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy, Centre for Integrated Catchment Management, University of Western Sydney, April 2003" Bibliography : leaves 338-356.
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Seakins, Amy Jane. "Meeting scientists : impacts on visitors to the Natural History Museum, London". Thesis, King's College London (University of London), 2015. http://kclpure.kcl.ac.uk/portal/en/theses/meeting-scientists(7365644c-734b-4970-a61e-4d3597dd803e).html.
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This thesis focuses on how face-to-face interactions with scientists, during a visit to a natural history museum, can have an impact on how visitors conceptualise and identify with researchers. The study draws together the literature on attitudes to science and perceptions of scientists, whilst also focusing on identity development in individuals, using the concept of interest to study impacts on engagement. The study adopted a qualitative approach primarily involving interviews with 81 adult visitors and 38 A-level students (aged 16-18) meeting scientists in museum-based discussion events. Participants were interviewed before, immediately after, and two months after meeting scientists to explore longer-term impacts. Meeting scientists had an impact on visitors’ and students’ identification of and with scientists. Visitors and students held conceptual ecologies around perceptions of scientists, drawing on multiple ideas about scientists concurrently. Visitors and students identified more closely with scientists following their interaction, recognising common experiences, and visitors also developed a lasting interest in scientists and their career histories. I propose the notion of scientists as ‘everyday experts’: knowledgeable individuals with clear areas of expertise who are also approachable and accessible. A ‘midway’ approach to public engagement is recommended to facilitate the presentation of scientists as ‘everyday experts’; an intermediate approach between a deficit, one-way communication and a two-way dialogue between scientists and the public. Meeting scientists is shown to bring ‘added value’ in terms of increasing scientific literacy: perceptions of scientists became more positive and less stereotypical and participants learned about particular areas of science as a result of the session. Meeting scientists was also shown to provide ‘added value’ in promoting science engagement: visitors reported continued engagement with science in the delayed post-session interviews two months after the visit. I discuss the implications of my findings for research and practice, with the aim of further understanding how to develop scientific literacy and engagement.
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Barros, Maria Isabel Amando de. "Caracterização da visitação, dos visitantes e avaliação dos impactos ecológicos e recreativos do planalto do Parque Nacional do Itatiaia". Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-23092003-140646/.
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O presente trabalho teve como objetivos descrever e avaliar as condições atuais dos impactos ecológicos e recreativos em trilhas e áreas de acampamento, além de obter conhecimentos sobre a visita e os visitantes do Planalto do Parque Nacional do Itatiaia (PNI). Com base nas informações obtidas, procurou-se compreender as relações uso-impacto e explorar as diretrizes para um programa de educação do visitante voltado para a prática de técnicas de mínimo impacto que contribuísse para atenuar os danos identificados. As informações sobre a visita e os visitantes foram obtidas através da aplicação de um questionário a 605 pessoas entre os meses de Fevereiro a Agosto de 2002. A avaliação das condições das trilhas e áreas de acampamento foi feita através do levantamento detalhado de indicadores de impactos ecológicos e recreativos. A partir de 1996 o número de visitantes no Planalto teve um aumento relativo maior do que na parte baixa do Parque, demonstrando que a demanda por atividades ligadas a caminhadas, ascensão de picos, escalada e acampamento aumentou. Entretanto os dados obtidos mostram que cerca de 84% das pessoas que visitam o Planalto do PNI concentram suas atividades em três lugares: o Pico das Agulhas Negras, o Pico das Prateleiras e o Abrigo Rebouças. A concentração do uso nas trilhas citadas possivelmente contribuiu para a ocorrência de valores significativamente diferentes encontrados para os indicadores de impactos relacionados à largura total, à profundidade do canal e à área transversal das trilhas estudadas. O nível educacional dos visitantes do Planalto é alto, com 72% das pessoas cursando ou com nível universitário completo. Esse dado, aliado ao fato de que 90% dos visitantes mencionaram que as ações de manejo do uso público presentes atualmente no Planalto não alteraram ou melhoraram a qualidade da sua visita é um indicativo de que os visitantes são receptivos a uma maior presença de ações de manejo da visitação e da aceitação de um programa de educação do visitante. A avaliação dos indicadores de impacto das áreas de acampamento mostrou que todos os indicadores sofreram uma diminuição nos valores entre os anos de 1998 e 2002, com exceção da área de solo nu, como resultado do fechamento das áreas após um incêndio no maciço das Prateleiras em Julho de 2001. O levantamento detalhado dos impactos nas áreas de acampamento mostrou que os problemas mais graves estão relacionados ao uso público e são resultado da falta de informação e conhecimento técnico dos visitantes sobre a magnitude dos impactos causados pela atividade de camping e as formas de minimizá-los. Com base nos resultados encontrados foram elaboradas diretrizes que poderão compor um programa de educação sobre técnicas de mínimo impacto para o Planalto do PNI. Elas devem incluir técnicas relacionadas aos seguintes temas: deteriorização das trilhas estabelecidas, abertura de trilhas secundárias, deteriorização de áreas de acampamento estabelecidas, proliferação de áreas de acampamento, lixo, dejetos humanos e aglomerações.The goals of this research were to describe and evaluate the current ecological and social impact on trails and campsites, as well as to characterize the visit and visitors of upper Itatiaia National Park (INP). Based on this information, it was intended to understand impact-use relationships and to explore the guidelines of a visitor education program designed to encompass minimum impact techniques that would contribute to minimize the problems found. A questionnaire was applied to 605 people from February to August 2002 in order to get information about visit and visitors. Trails and campsites conditions were assessed through ecological and social indicators. After 1996 the number of visitors at the Parks upper lands was comparatively higher than the number of visitors at the lower Park. This demonstrates that there was an increase of interest about activities related to climbing, camping and hiking. Meanwhile around 84% of people that visit PNI highlands are concentrated at the two main peaks of the area, Agulhas Negras and Prateleiras, besides Rebouças Hut. The fact that the use is concentrated on the two mentioned trails possibly contributes to the values significantly different found in the impacts related to total trail width, trail depth and trail transversal area. The educational level of visitors is high, since 72% are in college or have a college degree. This and the fact that 90% of visitors mentioned that the presence of management actions did not disturb or contributed to their experience, is an indicator that PNI visitors are receptive to a higher presence of recreation management and would accept a visitor education program. The campsite impact assessment revealed that from 1998 to 2002 all indicators were reduced, with the exception of total bare area. That is the result of the campsites closure after a fire at Prateleiras Area in July 2001. The detailed assessment of campsite areas shows that the most important problems are related to use and result from lack of information and technical knowledge about impacts caused by camping activities and about ways to minimize them. Based on the results found guidelines of a visitor education program about minimum impact techniques were designed. They should include techniques related to the following issues: deterioration of constructed trails, development of undesired user-created trails, proliferation of campsites, deterioration of established campsites, litter, human waste and crowding.
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McLean, Kevin Daniel. "Interpreter Attributes and Their Impact on Visitor Outcomes in National Park Service Interpretive Programs". Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/19288.
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By revealing deeper meanings and connecting the visitor to the resource, interpretation strives to accomplish a number of goals. Interpretation can increase knowledge of a program\'s topic, change the visitor's attitude toward something, change future behaviors, and increase appreciation for a place and its resources. While literature exists professing best practices for interpretation, little empirical support is present in the research literature to validate these practices' individual links to desired outcomes. This study empirically identifies attributes of the interpreter that statistically linked to visitor outcomes. We tracked 31 interpreter attributes and 10 intended outcomes of interpreters in 376 live interpretive programs in 24 units of the U.S. National Park Service (NPS) and conducted visitor surveys immediately following the programs. This research addresses the following question: Which interpreter attributes most consistently lead to desired outcomes? Our research shows that the interpreter attributes most consistently associated with positive visitor outcomes were the interpreter's apparent degree of confidence and expression authentic emotion. The results can be used to inform interpretive training throughout the National Park Service.Master of Science
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Whalley, Peter A. "Resident perceptions of the sociocultural impacts of tourism in Llangollen, north-east Wales". Thesis, Sheffield Hallam University, 2000. http://shura.shu.ac.uk/20521/.
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Taking as its starting point the need to better understand the relationship between tourism and culture in a western European context, this research develops and applies a conceptual framework and methodology to evaluate the attitudes among residents of a tourist receiving community to the sociocultural impacts of tourism. To this end, a case study approach is used to evaluate the attitudes of the residents of Llangollen, a small market town in North-east Wales, to the sociocultural impacts of tourism on their town and way of life. As host to the annual Llangollen International Musical Eisteddfod, and as a popular destination for day visitors and longer stay tourists alike, the community of Llangollen is a mature tourist destination possessing a wide range of tourist and cultural facilities. The study examines a range of appropriate literature and develops a conceptual framework around three key theories: the notion of resident 'coping strategies' to deal with the impacts of tourism, the sociological principle of social exchange theory and the social-psychological theory of social representations, with the latter being central to the study's methodology. There were three elements to the field work. Firstly, preliminary sensitising interviews were carried out in order to highlight key areas of local concern, and to inform the design of the survey work. Secondly, a questionnaire survey was undertaken of the residents of Llangollen, which was then interpreted using two different methods of respondent segmentation and using an assessment of the difference between groups. Finally, focus group discussions were carried out in the town in order to assist in the interpretation of the questionnaire findings and also to provide a systematically-derived set of qualitative data in order to assess the relative merits of taking different methodological approaches to the research. The findings of the research show that the community of Llangollen is generally positive about the impacts of tourism, with the role of the International Eisteddfod being pivotal in cultural terms. The three different approaches to the analysis of the impacts of tourism in Llangollen provided different perspectives and insights. The multivariate technique of cluster analysis gave the clearest picture from the questionnaire of resident perceptions of the cultural impacts of tourism, whereas an equity-based approach gave more indication of exchange processes at work in the community. The use of focus group discussions proved to be by far the most valuable in terms of drawing out not only what were the attitudes of residents, but also how and why such attitudes had come about in the first place. Most importantly, this research has made much clearer the political, economic and cultural contexts within which the residents of Llangollen perceive the impacts of tourism, and how it is these contexts which are influential in the attitudes taken to the impacts of tourism on the community, on groups in the community, and on the individual members of the community. The research also suggests there is a need for tourism research to move away from its traditional reliance on the questionnaire survey, and the search for statistically significant but perhaps socially irrelevant groups. It is suggested that further use of focus group discussions may help to more fully understand the relationships between tourism and culture within local communities.
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Milanowski, Shannon M. "Visitor Awareness of Low-impact Camping Techniques in the Wilderness Area Isle Royale National Park, Michigan: An Investigation of Possible Affecting Factors". Ohio : Ohio University, 2002. http://www.ohiolink.edu/etd/view.cgi?ohiou1037696738.
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East, Duncan. "Environmental performance of a conservation attraction : the potential impact of visitor learning and behaviour change". Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/420754/.
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Nature based visitor attractions desire to be a positive influence on the people who visit, whether they are day visitors, members or organised school groups. Much work has been done to evaluate learning in visitors with mixed results, and demonstrating actual change in behaviour as a result of any learning has only been possible in a few, narrowly focussed studies. Using a combination of GPS visitor tracking and surveys, never before tried on this scale in this type of attraction, variations in spatial behaviour were found with group type, with learning and with intention to change behaviour. Further public surveys, analysis of schoolchildren's drawings of animals, focus groups discussions and responses on Facebook were combined with the tracking analysis to give a unique insight into the influence of an attraction on visitor learning and behaviour change resulting from repeated contact. Conservation organisations and attractions strive to have a positive environmental impact, but operating a visitor attraction has negative environmental and social impacts, often in direct conflict with the aims of the organisation. The negative impacts could potentially, however, be alleviated, or compensated for, if enough visitors could be inspired to modify their behaviour in their lives away from the attraction. Visitors and schoolchildren to Marwell Zoo were confirmed to be learning during their visit, and visitors were open to calls to action to prevent biodiversity loss. A small proportion reported an intention to change behaviour following their visit, and some repeat visitors gave examples of behaviours they had already changed as a result of visiting Marwell Zoo. Recommendations are made to increase the proportion of visitors changing behaviour, and a mechanism is suggested to incorporate visitor behaviour change into overall environmental reporting.
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Swart, Lidia. "The impact of social media on the existence of visitor information centres in South Africa". Diss., University of Pretoria, 2016. http://hdl.handle.net/2263/60521.
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The visitor information centre (VIC) play a valuable role in the distribution of tourism-related information in most areas in South Africa that are frequented by tourists. They also provide a contact point for human interaction where trust can be built between the VIC staff and visitor, thereby making the destination a more worthwhile and valued experience. The main role of the VIC is to provide information in the form of knowledge also referred to as value-added information. Today, the VIC, as intermediary, could be left behind as the Internet (of which social media is part) has become a powerful source of information for tourists and marketing tool for hotels and tourist attractions without them having to spend millions of Rands on alternative marketing strategies. This study sought to establish whether VICs still have a role to play in the South African tourist industry with the increasing presence of social media.
A mixed method research methodology was applied, combining both qualitative and quantitative techniques. In-depth interviews were conducted with the staff and managers of selected visitor information centres in Cape Town and Johannesburg, respectively. The interviews were transcribed and the findings are presented in Chapter 5. Questionnaires was distributed, online, to a sample of 200 visitors, using Qualtrics.
Overall, the aim of the study is to furnish information about the value of VICs in the tourism industry, including the role played by demographics in respect of social media usage, in order to help improve the functioning of VICs as a knowledge base that adds value to the process of making South Africa one of the top 20 tourism destinations, globally, by 2020.Dissertation (MCom)--University of Pretoria, 2016.
Tourism Management
MCom
Unrestricted
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Giles, Andrew. "Exploring the Social, Environmental and Economic Aspects of Trail Surfacing Decisions". Thesis, University of Waterloo, 2002. http://hdl.handle.net/10012/964.
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Visitor activities in parks often have a heavy impact on the soil, vegetation, water and wildlife. In front country areas, the most extreme damage is concentrated on and adjacent to recreational trails. Aside from controlling the numbers, activities and behaviours of trail users, managers may choose to make trails more resistant to impact through surfacing. Unfortunately, surfacing may have negative influences on park visitors' enjoyment of trails by limiting access or detracting from the primitive setting. In addition, some surfaces may be ineffective in certain environmental conditions such as wet ground or steep slopes. Finally, the wide variety in construction and maintenance costs may make some surface types economically unfeasible.
The goals of this research are to investigate the role of trail surfacing in the management of impacts from outdoor recreation; to develop better understanding of the social, economic and environmental aspects of trail surfacing decisions; and to explore a comprehensive framework for incorporating these three factors in trail management. It is hoped that this research can assist park managers in selecting surfacing options to reduce visitor impact without excessively compromising recreational experience or organizational limitations, such as financial resources.
In addition to a comprehensive review of literature on visitor impact management on trails and surfacing techniques, this research employs three methods to further investigate the social, environmental and economic aspects of trail surfacing: a trail user survey, manager survey and trail condition assessment. The trail user survey was conducted at two well-used natural areas in southwestern Ontario, Canada: Presqu'ile Provincial Park and Belfountain Conservation Area. Surveys at each area explored trail users' perceptions and preferences of trail surfacing techniques in late summer 1999. The managers' survey provided insight into organizational approaches to surfacing, including construction cost and observations on recreational or environmental effectiveness. Finally, the trail condition assessment explored an approach to determining environmental effectiveness of trail surfacing techniques, but was limited by the physical and recreational variation between trails.
Seven recommendations for trail managers are presented, tying in several conceptual frameworks of visitor impact management and trail surfacing decisions developed in the thesis. First, trail managers are recommended to develop a full understanding of trail design principles and alternative visitor impact management techniques. If surfacing is selected as the best impact management technique, trail managers should obtain as much information on user characteristics, environmental conditions and organizational limitations as possible. Despite the benefits and drawbacks for all surfaces, road base gravel (or angular screenings with fines) merits special attention as an excellent surface, while asphalt and concrete are not recommended for front country, semi-primitive recreation. Finally, trail managers are encouraged to share information on surfacing more freely and open surfacing decision processes to affected trail users.
Overall, trail managers are provided with an approach to surfacing decisions that considers the social, environmental and economic aspects of trail surfacing, with the goal of working toward more enjoyable, environmentally responsible and cost-effective trail solutions.
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Cirino, Sílvia Fernandes Ribau. "Turismo e migrações : impacto das visitas a Portugal dos emigrantes". Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/1567.
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Mestrado em Gestão e Desenvolvimento em TurismoA mobilidade humana constitui uma característica do Homem, presente ao longo dos séculos, sob diferentes formas ditadas pela evolução dos povos e da vida em sociedade. Embora os fluxos migratórios façam parte da história da humanidade há muitos séculos atrás, os movimentos turísticos se democratizam e tomam proporções significativas apenas a partir do século XX. Neste contexto, o presente trabalho tem como objectivo principal contribuir para o conhecimento na área da mobilidade humana e mais precisamente, nas áreas do turismo e das migrações, e das interligações existentes entre estes dois conceitos. As visitas ao país de origem dos emigrantes fazem parte, de forma cada vez mais significativa, do projecto migratório e contribuem para um aumento considerável do mercado turístico nomeado Visita a Familiares e Amigos (VFA). A importância das ligações mantidas entre os emigrantes e a terra de origem, assim como as suas contribuições directas para o crescimento do turismo, estão claramente demonstradas neste trabalho de investigação. Os laços emocionais, sociais, políticos, económicos e comerciais que unem uma determinada região à sua comunidade residente no estrangeiro, contribuem para o aumento das remessas dos emigrantes e provocam um crescimento da frequência das visitas ao país de origem. Consequentemente, o volume dos fluxos turísticos assim como as receitas provenientes dos fluxos humanos originários da emigração, geram desenvolvimento do turismo internacional. Portugal, país de grande tradição emigratória, beneficiando directamente deste fenómeno, é objecto de estudo do presente trabalho. O estudo está centrado mais precisamente sobre o comportamento dos emigrantes do concelho de Ílhavo. São determinadas as principais características das viagens de regresso destes emigrantes, assim como a importância da intensidade das ligações mantidas com a sua terra de origem, para o crescimento do turismo receptor ao nível regional e nacional. ABSTRACT: Human mobility has been considered an important characteristic of the human being during centuries, dictated by people evolution and by the life in society. Although migratory flows form part of the human history since many centuries, tourist flows have been democratized in the twentieth century taking enormous proportions. In this context, the broad intent of this study is to contribute to the existing literature that addresses to develop forms of mobility such as tourism and migration, as well as the existing relationships between those two concepts. Return visits of migrants are increasingly part of the migratory project and contribute for a significant rise in the Visit Friends and Relatives (VFR) tourist market. This research work demonstrates the importance of the linkages maintained between the migrant community and their home country, as their direct contributions to the growth of tourism. Emotional, social, political, economic and commercial linkages between a region and its resident abroad community, contribute to increase fund transfers from migrants, coming from host country, and to increase the frequency of return visits. Consequently, the volume of tourist flows, as well as the receipts coming from these human flows originated by migration, contributes to the development of international tourism. Portugal, a country with a large emigration tradition, profiting directly from this phenomenon, is studied in this work. The research is focused, more precisely, on the behavior of the Council of Ílhavo’s emigrants. Principals’ characteristics of migrants’ return visits were found out, as well as the importance of the intensity of existing ties between those migrants and the home region, for the growth of inbound tourism at the regional and national level.
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Ng, Ho-yee Janet, i 伍可怡. "Impact of vision and hearing impairments on social participation". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B45010377.
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Brown, Amanda. "The Impact of Vision on Movement of Older Adults". Cleveland State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=csu1465758466.
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Coppo, Joseph Lewis 1963. "Impacts of near park development on visitor's perception of Tuzigoot National Monument, Arizona". Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277970.
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As the population of the United States increases, pressures on Park boundaries are also increasing. The buffer zones around park units are disappearing due to external encroachment, causing adverse effects to park resources. It has always been assumed that there will be a negative effect on Park resources resulting from near park development, but the effects have not been documented. This research examines the effect that near park development has on the overall quality of visitors experience at Tuzigoot National Monument. Subjects showed a preference for natural settings by consistently rating non-built development alternatives higher than residential and commercial alternatives.
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Alhumaid, Jameel. "The educational impacts of class visits to the Kennedy Museum of Art /". View abstract, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3205447.
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Wolf, Isabelle Diana Felicitas Gudula Biological Earth & Environmental Sciences Faculty of Science UNSW. "Towards sustainable tourism in outback Australia: the behaviour and impact of nature-based tourists on vegetation and selected wildlife species". Awarded by:University of New South Wales. Biological, Earth & Environmental Sciences, 2009. http://handle.unsw.edu.au/1959.4/44572.
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Nature-based tourism offers significant socio-economic incentives to successfully replace more intrusive land uses but also causes negative environmental impacts. Currently, knowledge is needed about the effectiveness of specific management actions such as the provision of different access modes and tour experiences at minimizing these impacts while maximizing visitor satisfaction. Nature-based tourism activities were studied in the species-rich gorges of the Flinders Ranges in Outback Australia. This study developed a conceptual framework of visitor-environment relationships, constructed a regional visitor profile, assessed visitor monitoring methods to quantify usage intensity in relation to the access mode (roads vs. hiking trails), examined changes in vegetation and bird communities in relation to usage intensity and access mode, tested effects of approach behaviour among driving vs. hiking tourists on kangaroo behaviour, and designed a framework for a night-time wildlife tour. The usage intensity of gorge sections was best determined from visitor numbers stratified by their behaviour, as the access mode fundamentally changed visitor behaviour in gorges. High compared to low usage recreational tracks altered species community composition, decreased total plant cover, increased non-native species cover, increased or decreased plant diversity depending on the track distance, increased soil compaction, and decreased bird numbers and species richness. Vegetation changes had secondary aversive effects on the bird community. The magnitude and spatial extent of these community impacts were greater along roads than trails. Visitor approach towards kangaroos varied with the access mode and necessitated individual recommendations for low-impact behaviour. The optimal night-time observation tour employed night-vision devices and bat detectors and coupled visitor satisfaction with low impact on wildlife. A range of factors (e.g., weather conditions) moderated the susceptibility of the wildlife to tourism disturbance. To protect wildlife and habitat along recreational tracks in arid-lands gorges, it is recommended to (1) monitor usage intensity and the identified impact indicators within their effect zone, (2) curtail gorge usage by restricting vehicle access to sections and regulating high impact activities (e.g., wild camping), (3) base environmental education upon scientifically tested low-impact visitor behaviour, and (4) engage with tourism operators in the design of low-impact, yet satisfying tours based on scientific principles.
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Chang-Hui, George Yang. "A study of foreign visitors, their motivations and impact on tourism development in Taiwan". FIU Digital Commons, 1988. http://digitalcommons.fiu.edu/etd/2110.
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The purpose of this research project was to analyze the reasons why foreign tourists visit Taiwan and their impact on the tourism industry in Taiwan.
The descriptive survey method was mainly derived from primary data sources. However, secondary data was used to supplement the primary data sources.
The study was concluded by supporting the hypothesis. The hypothesis stated that the attitude and the motivation of foreign tourists is identifiable.
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Kurdi, Heba. "The impact of visitors satisfaction in explaining expenditure behaviour : A structural equation modelling approach". Thesis, Högskolan Dalarna, Nationalekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:du-30030.
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Visitor expenditure can be affected by different economic, socio-demographic and psychological variables. Previous literature have focused on the use of observed tourists and destination characteristics as explanatory variables to explain visitor expenditure, whereas the use of psychological factors has been underresearched. The present study aims to fill in the gap in the existing literature through the exploration of more extensive use of psychological variables. This is accomplished by the use of structural equation modelling (SEM), a methodological approach which seems not to have been applied before in tourism expenditure econometric models. In econometrics expenditure research, Mortazavi (2018) found satisfaction to be an endogenous regressor of expenditure. Hence, the contribution of our model is that it allows for the relationship between visitor satisfaction and visitor expenditure, and vice versa, to be tested simultaneously. Consequently, under this context we may identify the magnitude of one variable impact on another while at the same time accounting for simultaneous relationship between the two paths. The findings of this study go in hand with previous literature and economic theory which have found a positive relationship between visitor satisfaction and visitor expenditure.
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Rigoulot, Simon. "Impact comportemental et électrophysiologique de l'information émotionnelle en vision périphérique". Phd thesis, Université du Droit et de la Santé - Lille II, 2008. http://tel.archives-ouvertes.fr/tel-00370746.
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Vision et Emotion sont deux fonctions adaptatives majeures dont les interactions ont été largement évaluées. Il est aussi reconnu que les performances visuelles déclinent fortement au fur et à mesure que les stimulations s'éloignent du centre du champ visuel. De ce fait, les études s'intéressant au traitement des informations visuelles émotionnelles ont systématiquement présenté ces stimulations en vision centrale (VC) mais jamais de manière excentrée, en vision périphérique (VP). Ce travail a pour objectif général d'explorer les réponses induites par des stimulations émotionnelles présentées en VP, aux niveaux comportemental et cérébral, grâce à la technique des potentiels évoqués (PE). Le caractère saillant de l'information émotionnelle, par sa capacité à capter préférentiellement les ressources attentionnelles, devrait : d'une part, optimiser la réactivité de la VP ; d'autre part, faciliter la rééducation de pathologies de la VC (scotomes centraux), dans la mesure où, lors de ces pathologies, seules les ressources de la VP demeurent disponibles.En premier lieu, nous avons voulu explorer la capacité de la VP à traiter des images de scènes naturelles dont certaines contiennent des informations émotionnelles. Nous avons notamment observé pour la première fois l'existence de composantes électrophysiologiques évoquées par la VP. De plus, nous avons pu constater que le contenu émotionnel des images module les performances comportementales des participants ainsi que leur activité cérébrale, comme classiquement décrit en VC. Ces résultats plaident en faveur d'une différentiation précoce des informations visuelles présentées en VP selon leur nature affective et permet d'envisager leur utilisation dans le cadre de la rééducation neurovisuelle.
En deuxième lieu, et ayant à l'esprit les possibilités de rééducation neurovisuelle, nous avons cherché les stimulations susceptibles de mobiliser au mieux les ressources visuelles, pour ensuite les associer, en VP, à des informations émotionnelles. En conséquence, nous nous sommes intéressés au traitement de visages émotionnels (peur, neutre, joie) en VP car ils constituent, du fait de leur rôle dans les interactions sociales, des stimulations visuelles particulièrement saillantes. Cette étude a permis de montrer que les visages sont traités en VP et que leur expression émotionnelle a un impact au niveau comportemental et électrophysiologique. En particulier, les réponses des participants sont plus rapides et les composantes évoquées sont plus amples lorsque des visages de peur et de joie sont présentés en VP par rapport à des visages neutres.
Enfin, certaines études suggèrent une amélioration des performances de la VP lorsque des stimuli sont présentés en mouvement. De ce fait, la saillance des visages en VP pourrait être renforcée par le caractère dynamique de leur expression émotionnelle. Dans une troisième expérience, nous avons donc présenté des visages statiques et des visages animés, neutres et émotionnels, en VC et en VP. Les résultats obtenus confirment les données de la seconde expérience mais ne permettent pas d'attribuer un avantage spécifique à la composante dynamique des visages présentés, qu'ils soient émotionnels ou neutres.
A titre prospectif, nous avons présenté, à des patients atteints de scotomes centraux, des visages émotionnels et neutres. Les résultats comportementaux permettent de mettre en évidence que, chez ces patients, les visages émotionnels sont mieux traités que les neutres en VP. Les expressions faciales émotionnelles pourraient donc s'avérer des stimuli particulièrement adaptés dans le cadre de l'amélioration des ressources de la VP.
En conclusion, ce travail apporte des données comportementales et électrophysiologiques inédites sur le codage de l'information émotionnelle en VP et ouvre des perspectives encourageantes sur l'utilisation de la saillance émotionnelle dans la rééducation des déficits de la vision centrale.
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Whittam, Daniel J. "The impact of cataract surgery on driving and vision performance". Thesis, Queensland University of Technology, 2002. https://eprints.qut.edu.au/36774/1/36774_Digitised%20Thesis.pdf.
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Background:
Previous research has shown that cataracts and cataract surgery impact upon driving and vision performance. The research on driving has primarily relied upon self-reported performance measures or simulation techniques to determine the results. Many studies have also shown visual function, including visual acuity, contrast sensitivity and disability glare, to improve following cataract surgery.
Limitations of these studies are that (a) patients self-perception may not reflect actual driving performance, (b) simulation studies make inferences about real world driving performance and ( c) studies in clinical settings lack real world applications.
Aims:
To investigate the effect of cataract surgery on actual driving and vision performance.
Subjects:
Sixteen subjects (mean age 71.31±8.53 yrs) who underwent bilateral cataract surgery and 16 control subjects (mean age 66.31 ± 7.00 yrs) who had VA 6/7.5 or better and an absence of eye disease participated in the study. All subjects held a current drivers license.
Methods:
Vision and driving performance were measured before and after cataract surgery in the first and second eye of the cataract subjects. Driving performance was measured under day-time conditions on a closed road circuit as described by Wood and Troutbeck, (1994), measures included, road sign recognition, course time, road obstacle detection, reaction time, reversing, lane-keeping, gap perceptions and manoeuvring. Self-reported driving performance was measured using the Activities of Daily Vision Scale (ADVS) described by Mangione et al. (1992). Vision measures included, visual acuity, contrast and glare sensitivity. The control group completed the same series of trials with similar times between testing sessions.
Results:
Significant improvements (p < 0.05) in driving performance measures were shown after bilateral cataract surgery, including the number of road signs seen, driving course time and the number of low contrast road obstacles seen and avoided. Visual performance improved significantly after bilateral cataract surgery for binocular visual acuity and contrast sensitivity with and without disability glare measured by the Brightness Acuity Tester. Patient's self-perceptions of vision and quality of life as measured by the ADVS also displayed similar improvements.
Conclusions:
Bilateral cataract surgery significantly improved driving and vision performance. This was also reflected by patient's self-perceptions of their performance.
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Salewski, Katja. "Museum Personalized : The impact of floor staff on an exhibition - A holistic approach". Thesis, Högskolan Dalarna, Vetenskapskommunikation, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:du-2534.
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The current paper presents a study conducted at The National Museum of Science and Technology in Stockholm to investigate the exhibition “Antarctica – that’s cool” from its first concept to the first workshop that is held in the exhibition. The focus is on the influence of floor staff on an exhibition and workshops as learning facilities in museums. Findings, based on visitor observation and the exhibition building process, go into the characteristics of low-budget productions and discuss the importance of staff on the exhibition floor for museums as life-long learning facilities. The holistic approach of the study provides deep insights into the complex interplay of visitors, staff and exhibitions. The results can be used for future exhibition building processes and educational programs in museums and should strengthen the museum’s position as life-long learning facility in nowadays society.
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Belin, Laurine. "Impact des stimuli visuels sur la réactivité émotionnelle". Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1B058.
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Au cours de cette thèse, nous nous sommes demandé si certains stimuli visuels pouvaient avoir une valence émotionnelle universelle chez les vertébrés. Une première série d’expériences a été réalisée en laboratoire sur diverses espèces d’oiseaux. Au terme de ces expériences, un stimulus visuel en particulier a pu être identifié : lors de sa diffusion ce stimulus a induit 1) des retraits/envols rapides (i.e. environ 2 secondes après le début de la diffusion) chez une majorité d’individus ; 2) un changement de trajectoire d’un groupe d’oiseaux en vol, et 3) a gardé une valence émotionnelle négative pour les oiseaux, même après des diffusions répétées. Dans une seconde phase, ce même stimulus a été testé sur une large gamme d’espèces d’oiseaux en conditions naturelles. Nous avons alors pu 1) valider l’impact émotionnel négatif de ce stimulus ; 2) révéler une sensibilité différente aux caractéristiques chromatiques du stimulus selon l’espèce, mais également 3) son efficacité à long-terme sur des oiseaux en contexte alimentaire. Enfin, la perception de stimuli visuels dont la valence émotionnelle était connue chez les oiseaux, a été étudiée chez le cheval et l’Homme. Il a été mis en évidence que certains stimuli capturaient l’attention de ces 2 espèces De plus, la présence d’un trouble du spectre autistique semble influencer la perception de certains stimuli visuels. Ce travail de thèse a mis en évidence l’existence d’un stimulus visuel ayant une valence émotionnelle universelle chez les oiseaux. L’influence de deux facteurs principaux sur la perception de cette valence émotionnelle a été également révélée : 1) facteur spécifique et 2) facteur développementalIn this thesis, we wondered if some visual stimuli could have universal emotional valence in vertebrates. A first series of experiments was conducted in the laboratory on various species of birds (e.g. starlings, Japanese quail and raptors). Each species of bird tested, negatively perceived a visual stimulus in particular. Indeed, during its display this stimulus induced 1) rapid withdrawals/takeoffs in a majority of individuals (about 2 seconds after the start of the display); 2) a change of trajectory of a group of birds in flight, and 3) kept a negative emotional valence for birds, even after repeated displays. In a second phase, the same stimulus was tested on a wide range of bird species (eg shorebirds, gulls, ducks and pigeons) under natural conditions. We were then able to 1) validate the negative emotional impact of this stimulus; 2) reveal a different sensitivity to color characteristics of the stimulus according to species, and also 3) its long-term effectiveness on bird food context. Finally, the perception of visual stimuli whose emotional valence was known in birds has been studied in horses and humans. Visual attention was mainly noted in these two species. Moreover, the presence of an autism spectrum disorder seems to influence the perception of certain visual stimuli. This work has highlighted the existence of a visual stimulus with universal emotional valence in birds. The influence of two factors on the perception of the emotional valence was also revealed: 1) specific factor and 2) developmental factor
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Kovarski, Caroline. "Impact des troubles visuels sur la performance scolaire". Thesis, Lyon 2, 2015. http://www.theses.fr/2015LYO20004/document.
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Beaucoup d'adolescents sous-estiment leur inconfort visuel, bien qu'il puisse affecter leur scolarité. La prévalence des troubles visuels chez des participants âgés de quinze à vingt-deux ans a été étudiée et les résultats obtenus ont été comparés à leur niveau scolaireEntre septembre 2012 et avril 2013, quatre cents jeunes gens âgés de quinze à vingt-deux ans ont répondu à un questionnaire relatif à des signes d’asthénopie, suivi d’un examen visuel (réfraction, fonctionnement accommodatif et vision binoculaire), afin de détecter des gênes visuelles dont ils pourraient ne pas être spontanément conscients. Lorsque des problèmes visuels ont été détectés, il a été proposé aux participants de passer un examen ophtalmologique et un bilan orthoptique. Puis, le niveau scolaire de ces quatre cents jeunes a été expertisé. Les participants ont ensuite été revus pour déterminer si le port d'une correction optique adaptée et/ou la prise en charge orthoptique ont permis d'obtenir une amélioration de la performance scolaire.Les résultats indiquent que le score au questionnaire est significatif pour prédire la probabilité d’avoir une faible performance scolaire et d’avoir des troubles visuels, que les anomalies de la réfraction et de l’accommodation ont un réel impact sur la performance scolaire et plus encore, que ce sont les troubles de la vision binoculaire qui sont les plus pénalisants. Surtout, l’absence d’une plainte visuelle spontanément exprimée ne permet pas de conclure à l’absence de problèmes visuels.Une fois la performance scolaire contrôlée par des variables utilisées habituellement pour l’expliquer (e.g. retard scolaire, CSP du chef de famille, sexe, etc.), une partie non négligeable des difficultés scolaires des participants proviennent de problèmes liés à la vision. Par conséquent, un dépistage systématique des troubles visuels chez les adolescents semble nécessaire, d’autant plus s’ils rencontrent des difficultés scolaires. Par ailleurs, le questionnaire mis en place dans l’anamnèse semble être un outil efficace dans la détection de la présence de troubles et mériterait d’être validé sur un plus large échantillonMany students understate their visual discomfort, although it may have an educational impact. We studied the prevalence of visual disorders among students and compared these results to their academic level.Between September 2012 and April 2013, four hundred students between fifteen and twenty two years of age responded to a questionnaire followed by a visual screening (refraction and binocular vision) in order to detect any visual discomfort that they might be unaware of. When visual problems were detected, the participants were asked to have an ophthalmology and orthoptic assessment. Then the participants’ academic performance was appraised and subjects were reviewed to determine whether wearing the appropriate optical correction or taking orthoptic care have improved their grades.The results indicate that the questionnaire score is very significant to predict the probability of having academic difficulties or vision problems, that ametropia and accommodation anomalies increase academic difficulties and that binocular vision disorders are even more disadvantageous. Moreover, not spontaneously expressing visual discomfort doesn’t mean that there are no visual defects.Once controlled by variables commonly used to explain academic difficulties (e.g. academic delay, occupational category, gender, etc.) a significant proportion of participants’ academic difficulties are related to vision anomalies. Therefore, vision screening among adolescents appears to be necessary, especially if there are academic difficulties. In addition, the questionnaire used in case history seems to be an effective tool to detect vision anomalies and should be validated with a larger sample
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Kim, Min Kook. "Monitoring Vegetation Change by Using Remote Sensing: An Examination of Visitor-Induced Impact at Cadillac Mountain, Acadia National Park". Fogler Library, University of Maine, 2010. http://www.library.umaine.edu/theses/pdf/KimMK2010.pdf.
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Ngu, Wee Sing. "The impact of Endocuff Vision on adenoma detection rates in colonoscopy". Thesis, Durham University, 2018. http://etheses.dur.ac.uk/12516/.
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Background: One of the problems with colonoscopy is its imperfection due to variation in operator dependent adenoma detection rates. Low adenoma detection rates are linked to increased interval colorectal cancer rates and reduced cancer survival. Devices to enhance mucosal visualisation and improve adenoma detection rates such as Endocuff Vision have been developed. The primary aim of this study was to compare adenoma detection rates between Endocuff Vision-assisted colonoscopy and standard colonoscopy. Methods: A multicentre, randomised controlled trial in seven hospitals in the United Kingdom was undertaken. Patients aged 18 and above referred for colonoscopy due to symptoms, colonoscopy surveillance, or as part of the Bowel Cancer Screening Programme following a positive screening faecal occult blood test were invited to the study. Patients with a suspicion of bowel obstruction, known colon cancer, polyposis syndromes, known strictures, active colitis, on anticoagulant therapy during the procedure, pregnant, attending for a therapeutic procedure or assessment of a known lesion were excluded. Findings: One thousand, seven hundred and seventy-two patients (57% male, mean age 62) were recruited from November 2014 until February 2016. Patient characteristics were comparable between trial arms. Endocuff Vision increased adenoma detection rates by 4.7% (p=0.02). This was largely driven by an increase in adenoma detection rates in screening patients from 50.9% to 61.7% (p < 0.001). Endocuff Vision-assisted colonoscopy also detected more mean adenomas per procedure, left sided adenomas, sessile serrated adenomas, diminutive adenomas, small adenomas and cancers. Cuff removal rate was 4.1%. Median intubation time was one minute quicker with Endocuff Vision-assisted colonoscopy (p=0.001). Anal intubation was rated as more uncomfortable with Endocuff Vision-assisted colonoscopy. There were no significant cuff-related adverse events. Endocuff Vision-assisted colonoscopy was non-inferior to SC in other markers of comfort and procedure time. Conclusion Endocuff Vision significantly improved ADR driven by an improvement in the faecal occult blood test positive screening population. Endocuff Vision-assisted colonoscopy was non-inferior in all aspects other than discomfort on anal intubation.
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Liu, Bing. "The impact of diplomatic visits on China's international trade and FDI". Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7418/.
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If the media and politicians are to be believed diplomatic visits from government officials and their entourage to existing and potential trade partners can have a dramatic impact on future international trade and investment, China’s emergences as a global trading power has put visits from and to China in the spot light. In this thesis, we examine the impact of Chinese leaders’ visits as well as the impact of foreign dignitaries who have visited China on China’s international trade and FDI. Employing log-linear and Poisson Pseudo Maximum Likelihood (PPML) approaches, the gravity model finds little evidence that diplomatic visits are effective to promote international trade between China and the rest of world. Diplomatic visits appear to exert different impact on trade with two relatively homogeneous groups of countries, African countries and OECD countries. In addition, it is found that diplomatic visits are significantly associated with a higher amount of OECD outward FDI to China.
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Abdullah, Fadhlin. "The Malaysian construction industry : an analysis on the impact of Vision 2020". Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393454.
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Winter, Simon. "Transverse Chromatic Aberration and Vision: Quantification and Impact across the Visual Field". Doctoral thesis, KTH, Biomedicinsk fysik och röntgenfysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-186334.
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The eye is our window to the world. Human vision has therefore been extensively studied over the years. However, in-depth studies are often either limited to our central visual field, or, when extended to the periphery, only correct optical errors related to a narrow spectrum of light. This thesis extends the current knowledge by considering the full visible spectrum over a wide visual field. A broad spectrum means that the wavelength dependence of light propagation inside the eye has to be considered; the optics of the eye will therefore not form a retinal image in the same location for all wavelengths, a phenomenon called chromatic aberration. We present here a new methodology to objectively measure the magnitude of transverse chromatic aberration (TCA) across the visual field of the human eye, and show that the ocular TCA increases linearly with off-axis angle (about 0.21 arcmin per degree for the spectral range from 543 nm to 842 nm). Moreover, we have implemented adaptive psychophysical methods to quantify the impact of TCA on central and peripheral vision. We have found that inducing additional TCA degrades peripheral grating detection acuity more than foveal resolution acuity (more than 0.05 logMAR per arcmin of induced TCA peripherally compared to 0.03 logMAR/arcmin foveally). As stimuli to evaluate peripheral vision, we recommend gratings that are obliquely-oriented relative to the visual field meridian. The results of this thesis have clinical relevance for improving peripheral vision and are equally important for retinal imaging techniques. To limit the negative impacts of TCA on vision, inducing additional TCA should be avoided when the peripheral refractive errors are to be corrected, such as for people suffering from macular degeneration and central visual field loss. In retinal imaging applications, TCA leads to lateral offsets when imaging is performed in more than one wavelength. Consequently, the measurement of TCA together with careful pupil alignment and subsequent compensation can improve the functionality of these instruments.Ögat är vårt fönster mot världen, och syn har mätts och studerats i stor utsträckning över åren. Trots detta är forskningen om mänsklig syn oftast begränsad till det centrala synfältet, och i studier av det perifera synfältet korrigeras optiska fel endast över ett smalt våglängdsområde. Denna avhandling vidgar forskningen om vår syn till att inkludera hela det synliga spektrumet över ett stort synfält. Ett brett spektrum innebär att vi måste ta hänsyn till våglängdsberoendet i ljusets brytning i ögat; ögats optik kan därför inte avbilda ett objekt till samma bildläge på näthinnan för alla våglängder, ett fenomen som kallas kromatisk aberration. Vi presenterar här en ny metod för att mäta mängden transversell kromatisk aberration (TCA) över ögats synfält och visar att ögats TCA ökar linjärt med vinkeln ut i synfältet (ungefär 0,21 bågminuter per grad från 543 nm till 842 nm). Dessutom har vi implementerat adaptiva psykofysiska mätmetoder för att kvantifiera effekten av TCA på central och perifer syn. Våra resultat visar att extra inducerad TCA påverkar den perifera förmågan att upptäcka sinusformade randmönster mer än den centrala förmågan att upplösa motsvarande ränder (mer än 0,05 logMAR per bågminut inducerad TCA i periferin jämfört med 0,03 logMAR/bågminut centralt). Vid utvärdering av perifer syn rekommenderar vi att använda sinusformade randmönster med en sned riktning jämfört med synfältsmeridianen. Resultaten som presenteras i avhandlingen har klinisk betydelse för att förbättra den perifera synen och är även viktiga för tekniker som avbildar ögats näthinna. För att begränsa den negativa effekt TCA har på synen ska man undvika att inducera extra TCA, t.e.x. när ögats perifera refraktiva fel korrigeras med glasögon för människor med makula degeneration och centralt synfältsbortfall. Vid avbildning av näthinnan ger ögats TCA förskjutningar mellan bilder i olika våglängder. Därför kan mätningar av TCA, tillsammans med välkontrollerad linjering av pupillens position och efterföljande kompensation, förbättra funktionen hos dessa instrument.
QC 20160511
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Nieman, Chelsey L. "Visual Ecology of Lake Erie Fishes: An Investigation of the Impacts of ElevatedTurbidity on Vision". The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1555421470203573.
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Ballantyne, Gavin. "Ants as flower visitors : floral ant-repellence and the impact of ant scent-marks on pollinator behaviour". Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2535.
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As flower visitors, ants rarely benefit a plant, commonly disrupting pollination by deterring other flower visitors, or stealing nectar. This thesis examines three aspects of ant-flower interactions, focusing on the occurrence of floral traits that prevent disruption of pollination and a novel means by which ants may influence pollinator behaviour. To assess which types of plant species possess ant-repelling floral traits I carried out a survey of 49 Neotropical plant species. Around a third of these species were repellent to the common generalist ant Camponotus novograndensis (Formicinae). This repellence was positively correlated with large nectar volumes within individual flowers. It appears that there has been selection for floral ant-repellence as a defence against ant thieves in plant species that invest in large volumes of nectar. In some cases these repellent traits were effective against a wide range of ant species. However, in no plant species were predacious ants particularly repelled, indicating that there may be little selective pressure on non-ant-plants to defend potential pollinators from aggressive ants. To investigate the importance of coevolution in determining the effectiveness of ant-repellents, a small but diverse range of Mediterranean plant species were tested with the invasive nectar thieving ant Linepithema humile (Dolichoderinae) and the native but non-nectar thieving ant Messor bouvieri (Myrmecinae). Responses of both ant species to floral traits were very similar. The ability of some plants to restrict access to ant species with which they have no evolutionary history may help to reduce the impact invasive species, as nectar thieves, have on plant-pollinator interactions. It is reported that flowers recently visited by bees and hoverflies may be rejected for a period of time by subsequent bee visitors through the detection of scent-marks. Nectar-thieving ants could potentially influence the foraging decisions of bees in a similar way if they come to associate ant trail pheromones or footprint hydrocarbons with poor reward levels. However, my empirical work found no differences were found in bee visitation behaviour between flowers of Digitalis pupurea (Plantaginaceae), Bupleurum fruticosum (Apiaceae) or Brassica juncea (Brassicaceae) that had been in contact with ants and control flowers. Ant-attendance at flowers of these species may not reduce reward levels sufficiently to make it worthwhile for bees to incorporate ant scent-marks into foraging decisions. Investigations like these into the interactions between ants, flowers and other flower visitors are essential if we hope to understand the part ants play in pollination ecology, and determine how ants have helped shape floral evolution.
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Fort, Patrice. "Rôle de la dystrophine Dp71 dans l'oeil : Impacts phénotypiques". Université Louis Pasteur (Strasbourg) (1971-2008), 2005. https://publication-theses.unistra.fr/public/theses_doctorat/2005/FORT_Patrice_2005.pdf.
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Le premier phénotype à avoir été décrit chez les patients souffrant de la dystrophie musculaire de Duchenne (DMD) est la dégénérescence musculaire progressive liée à l’absence du produit long issu du gène DMD : la dystrophine. Les différents travaux menés par la suite ont conduit à la mise en évidence d’autres troubles chez ces patients, affectant notamment leurs performances cognitives de façon non progressive. Ces travaux ont également permis de montrer que ces affections étaient liées aux produits courts du gène DMD et tout particulièrement à la Dp71. La Dp71 est le produit du gène majoritairement exprimé dans de nombreux tissus parmi lesquels le système nerveux central y compris la rétine. La découverte au milieu des années 1990, que 80% des patients DMD présentent une perturbation de la neurotransmission rétinienne, nous a conduit à étudier le rôle des dystrophines, et en particulier la Dp71 dans la rétine, à l’aide d’une souris transgénique pour laquelle l’expression de cette protéine a été invalidée. Cette étude nous a permis de montrer que la Dp71 est uniquement exprimé par les principales cellules gliales de la rétine, les cellules gliales de Müller, où elle est seulement accompagnée par l’utrophine, le produit d’un gène homologue du gène DMD. Nous avons ensuite montré que la Dp71 est responsable de la localisation de deux protéines, le canal potassique Kir4. 1 et le canal aqueux AQP4 qui sont essentielles à la régulation de l’homéostasie dans la rétine. De plus, l’absence de Dp71 entraîne une augmentation importante de la mort neuronale suite à un épisode ischémique, mettant en exergue l’intervention de la Dp71 dans la régulation de l’homéostasie rétinienne. Lors de l’étude clinique de la souris déficiente pour la Dp71, nous avons découvert un autre phénomène pathologique lié à l’absence de cette protéine : une cataracte congénitale progressive. Les dystrophines n’ayant jamais été étudiées dans le cristallin, nous avons caractérisé leur expression dans cette structure et montré que la Dp71 est également le produit du gène DMD majoritaire présent. Elle est principalement exprimée à la membrane des fibres secondaires du cristallin où elle colocalise avec le β-dystroglycane et le canal aqueux AQP0. Bien que des études complémentaires soient nécessaires, ces résultats indiquent qu’elle participe à un complexe macromoléculaire responsable de la conservation de l’intégrité de la membrane des fibres secondaires du cristallin. L’ensemble de ces travaux met en évidence le rôle de la Dp71 dans la vision, aussi bien dans un tissu nerveux, la rétine, que dans un tissu épithélial très spécifique : le cristallinThe first phenotype to be described among patients suffering from the Duchenne muscular dystrophy (DMD) is the progressive muscular degeneration related to the absence of the hole DMD gene product: the dystrophin. Various work undertaken thereafter led to the description of others troubles among these patients, affecting in particular their cognitive performances in a nonprogressive way. These works also made it possible to show that these affections were particularly related to the DMD gene short products and particularly Dp71. Dp71 is the mainly expressed product of this gene in many tissus among which the central nervous system including the retina. The discovery, in the middle of the 1990’s, that 80% of the DMD patients present a disturbance of the retinal neurotransmission led us to study the role of the dystrophins and in particular Dp71 in the retina using a transgenic mouse in which the expression of this protein was inactivated. This study enabled us to show that this DMD gene product is only expressed by the main glial cells of the retina, the Müller glial cells, where it is only accompanied by the utrophin, the product of an homologous gene of the dystrophin. We have also shown that Dp71 was responsible for the localization of two proteins essential for the homeostasis regulation of the retina: the potassic channel Kir4. 1 and the aqueous channel AQP4. Moreover the absence of Dp71 induce a significant increase in neuronal death following an ischaemic event putting forward the intervention of Dp71 in the regulation of retinal homeostasis. At the time of the clinical study of the defective mouse for the Dp71, we discovered another pathological phenomenon dependent on the absence of this protein: the development of a progressive congenital cataract. Since dystrophins had never been studied in the crystalline lens, we first characterized their expression in this structure and showed that Dp71 is also there the main DMD gene product and that it is mainly expressed in the membrane of the crystalline lens secondary fibers where it colocalize with the β-dystroglycane and the aquaporin channel AQP0. Although complementary studies are necessary, this seems to indicate that it takes part in a macromolecular complex responsible for the conservation of the integrity of the membrane of secondary fibres of the crystalline lens. The whole of this work puts forward the role of Dp71 in the vision, as well in one part of the central nervous system, the retina, as in a very specific epithelial tissue, the crystalline lens