Academic literature on the topic 'Web sites – Barrier-free design'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Web sites – Barrier-free design.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Web sites – Barrier-free design"

1

Françoso, Maria Teresa, Diogenes Cortijo Costa, Mariana Mello Valin, and Rogério Rodrigues Amarante. "Free Software for Development of Web GIS in Tourism Accessibility." Applied Mechanics and Materials 256-259 (December 2012): 2953–56. http://dx.doi.org/10.4028/www.scientific.net/amm.256-259.2953.

Full text
Abstract:
Based on the concepts of social inclusion, universal design, and accessibility, this paper aims to describe the stages of the development and implementation of a Geographic Information System for the Internet (Web GIS) based on open source (OS) software. The Web GIS developed is called "Accessibility to Campinas Tourist Attractions", which provides information about cultural and natural attractions in Campinas/SP- Brazil, especially for people with disabilities or reduced mobility that prevents access these sites via public and private transportation. The verification of the existence or lack of accessibility equipment at bus stops and parking areas close to tourist attractions relies on current legislation (NBR 9050) that establishes the right to accessibility for disabled people to transportation, local culture, and leisure.
APA, Harvard, Vancouver, ISO, and other styles
2

Gaurav Arora and Anu Rathee. "“IVERY”- Interior Design Website." International Journal for Modern Trends in Science and Technology 6, no. 12 (January 1, 2021): 514–19. http://dx.doi.org/10.46501/ijmtst061298.

Full text
Abstract:
The complexity of Web sites are increasing and transforming into Web applications that contain business logic, interactivity, transaction handling and states. This phenomenon forces the Web developers to adapt more traditional software engineering techniques to keep the Web applications error free, maintainable, reusable, well documented etc. Many Web developers do not use any engineering techniques at all and design mainly to create as fashionable applications as possible with no regards on the application’s functionality. This results in applications that are hard to maintain and with poor functionality. The purpose with this thesis was to see if the use of a more traditional software engineering technique, namely the Unified Modeling Language with the newly added Web Application Extension, resulted in a Web application with good design regarding the maintainability of the application . To investigate the maintainability of an application, the maintainability was further divided into three sub criteria: extensibility, reusability and documentation. These three criteria were then applied on a case study were a Web application was designed. From the analysis of the final design, using the three criteria, the maintainability was derived. The result of the entire investigation showed that the UML WAE had a good support for extensibility, fair support for reusability and very good support for documentation. From these results the main conclusion was derived, that the use of UML WAE resulted in good design regarding the maintainability. However, the result is limited to our case study and the design created in that case. The result may have been different if the three criteria had been applied on a different case. Another aspect to consider is that the quality of a design is often dependent on the knowledge of the persons that carry out the design.
APA, Harvard, Vancouver, ISO, and other styles
3

Kohli, Ankita, Chunying Zhao, and Jun Kong. "Automatic Usability Evaluation of Mobile Web Pages with XML." International Journal of Handheld Computing Research 4, no. 3 (July 2013): 19–40. http://dx.doi.org/10.4018/jhcr.2013070102.

Full text
Abstract:
Recently, mobile browsing on the World Wide Web is growing rapidly. The growth has created a surge in the number of Web pages designed for mobile devices. To increase the usability of mobile browsing, the Mobile Web Best Practices have been proposed to guide the development of mobile-friendly Web pages. In this paper, the mobileOK checker, a free service provided by W3C, is used to automatically inspect the conformance of 46 popular mobile Web sites to the Mobile Web Best Practices. We analyze the evaluation results and provide suggestions for improving the design of mobile Web sites. In mobile browsing, different mobile devices have different screen sizes, layout structures, and styles to represent Web contents. Furthermore, mobile devices are developing fast. The diversity and fast development of mobile devices cause the mobile design guidelines changing over time. However, the mobileOK checker is not flexible to include new guidelines or customize a best practice rule to fit a specific mobile browsing scenario. To solve this problem, this paper presents a generic approach to represent the mobile design guidelines through an XML schema. Using the XML schema provides the flexibly to support evolving guidelines in an open format. To evaluate our approach, a prototype, WPChecker, has been developed.
APA, Harvard, Vancouver, ISO, and other styles
4

Oberhelman, David. "Lights, catalogues, archives!: a selected annotated list of web resources for film and television studies." Reference Reviews 28, no. 1 (January 14, 2014): 2–5. http://dx.doi.org/10.1108/rr-06-2013-0145.

Full text
Abstract:
Purpose – -- The purpose of this paper is to provide a selected list of free and subscription web resources for film and television (screen) studies. Design/methodology/approach -- Reference sources on film and other media studies were located, evaluated, and selected. The list is divided into four broad research categories; research databases and film catalogs (subscription products); film and television catalogs/databases (gratis); historical film streaming sites; and film studies portal sites. Findings -- There are a wide variety of resources available online that users can freely access as well as robust subscription products currently available to libraries to support research in film and television studies. Students and scholars can use both free and fee-based sites for film catalogs, film studies journal indexes, streaming video content, and other information and analysis on visual media. Originality/value -- There has not been a bibliographic list of online film studies resources undertaken since 2005, and many new web resources as well as databases have emerged in the field. The annotated list of resources in this study seeks to supplement and update what has been previously discussed in the LIS literature on web-based reference sources available for libraries supporting film and television studies.
APA, Harvard, Vancouver, ISO, and other styles
5

Kamiński, Tomasz, Paweł Kapica, and Mariusz Dzieńkowski. "Applying universal design principles to improve the websites of a selected university." Journal of Computer Sciences Institute 25 (December 30, 2022): 401–8. http://dx.doi.org/10.35784/jcsi.3059.

Full text
Abstract:
The purpose of the study was to analyze the website of a selected university in terms of usability and accessibility of user interfaces with particular attention to the guidelines of the Web Content Accessibility Guidelines (WCAG) standard. After taking into account all the guidelines, an improved version of the site was created that was free of the diagnosed errors and incompatibilities. Both sites were surveyed using the questionnaire method with the LUT checklist. A survey was also conducted using an eyetracker. Twenty participants took part in this study. The third method of evaluation was to analyze the sites using an automated tool - the WAVE plugin attached to a web browser. The data obtained from the research experiment were analyzed qualitatively and quantitatively. In case of the survey and the WAVE tool, only quantitative analysis was carried out. The results of the analyses carried out using the three methods show unequivocally that the author's website prepared by the authors is clearly better in terms of usability and accessibility than the website of the selected university.
APA, Harvard, Vancouver, ISO, and other styles
6

Clink, Kellian. "Review of websites of particular use to social work students and social workers." Reference Reviews 29, no. 4 (June 8, 2015): 2–7. http://dx.doi.org/10.1108/rr-12-2014-0341.

Full text
Abstract:
Purpose – This paper aims to provide a rationale for seeking out and making federal, state and non-governmental Web sites available to social work students and social workers and describe a number of valuable resources, primarily from the non-governmental agencies, as they can be more difficult to identify. Design/methodology/approach – Resources included here include those that illuminate policy issues in general followed by those dealing with specific populations or issues. They have been identified both by systematic study and the serendipity that results from 27 years of experience seeking resources for undergraduate and graduate students in social work. Findings – These Web sites provide timely and authoritative information of particular interest to social work students or practitioners: first, Web sites that help illuminate policy and practices related to supporting low income people; and then, Web sites focusing on specific (geographically or topically) information needs. Research limitations/implications – The author is most familiar with sources that have been useful to undergraduate social work students and graduate students in a program that focuses on rural social work. Practical implications – The information in the Web sites described is timely and authoritative and should be part of the resources that are made known to students, faculty and practitioners in this discipline to inform their work. Social implications – Not every library can afford to subscribe to the valuable research presented in social work journals. Nor can they afford to purchase every book that might be valuable to social workers. They can, however, be knowledgeable about Web sites that present good, data-rich information as well as models of successful programming and services. In addition, it seems valuable for social workers in one state to build on the ideas that other practitioners are utilizing in another state. These Web sites often provide that kind of cross-pollination. Originality/value – While the organizations that create these Web sites have been around for decades, the literature in library science focuses primarily on collection development activities around books, electronic books and journals, while the Web sites which are free, authoritative and timely get a lot less attention.
APA, Harvard, Vancouver, ISO, and other styles
7

Malysheva, Elena N. "Monitoring of the Russian Archival Institutions Web Sites in Terms of Search Engine Optimization." Herald of an archivist, no. 1 (2020): 116–30. http://dx.doi.org/10.28995/2073-0101-2020-1-116-130.

Full text
Abstract:
Sites as virtual representatives of memory institutions on the Internet perform many functions of these institutions. Currently, archival site building is developing quite actively, and the attention of researchers is focused on organization, data layout, and design. One of the most important tasks of a memory institution is to attract users. However, literature has been paying insufficient attention to optimization of the sites’ search engines. Thus, the author has turned to studying the sites of the federal archives in terms of their search engine optimization. Comparative analysis of the sites has been carried out according to such criteria as site quality index, number of external links to the resource, total social activity, as well as adaptability of the site for mobile devices. The PR-CY.ru service has been used as an analysis tool. Site Quality Index (IQS) is a new indicator introduced by Yandex instead of citation index to characterize the site’s usefulness to the user, taking into account a large number of factors and more truthfully reflecting the state of the information resource. According to the study, the State Archive of the Russian Federation (GARF) and the State Archive of Ancient Acts (RGADA) have the highest value of IQS, and are, thus, good sites from the user’s point of view. The majority of sites of federal archives have low IQS and need further improvement. An important indicator in website promotion is number of links to the website. In number of external links, the GARF and the Russian State Archive of the Navy (RGAVMF) are in the lead, while the Russian State Archive of Social and Political History (RGASPI) and the Russian State Archive of Literature and Art (RGALI) number most links from social networks. Sites of the RGAVMF and the Russian State Military Archive (RGVA) are optimized for mobile devices. Few sites have responsive design, which complicates access to their data. The author notes the need for regular site monitoring by means of web analytics. As a free site analysis tool, she recommends the PR-CY.ru service.
APA, Harvard, Vancouver, ISO, and other styles
8

Glusker, Ann. "Urban Public Libraries Do Not Yet Meet Benchmarks for Web Accessibility by Individuals with Disabilities." Evidence Based Library and Information Practice 10, no. 2 (June 14, 2015): 144. http://dx.doi.org/10.18438/b8pw32.

Full text
Abstract:
A Review of: Maatta Smith, S. L. (2014). Web Accessibility Assessment of Urban Public Library Websites. Public Library Quarterly, 33(3), 187-204. http://dx.doi.org/10.1080/01616846.2014.937207 Abstract Objective – To determine the extent to which urban public libraries in the United States of America provide web sites which are readily accessible to individuals with disabilities with reference to the Urban Library Council’s EDGE initiative (specifically Benchmark 11, “Technology Inclusiveness”). Design – Web site evaluation. Setting – Urban public libraries in the United States of America. Subjects – The 127 library systems, which were both members of the Urban Libraries Council at the time of the study and located in the United States of America. Methods – Using the “everyday life information seeking” conceptual framework, an assessment of each of the web sites of the purposive sample of public library systems was performed by an online evaluation tool as well as visually and physically to determine web accessibility and, by extension, technology inclusiveness. Main Results – The results of the online accessibility evaluation tool revealed that not one of the sites surveyed was free of errors or alerts. Contrast errors (related to color combinations), missing alternative text (providing text alternatives for visual elements), and missing form labels (thereby preventing screen readers from performing searches and navigating to results) were the most common problems. Results of visual and physical scans revealed that many sites lacked specific links and/or resources for persons with disabilities, as well as noting that the resources available used oblique language and required many clicks to access. In addition, the vast majority neglected to feature links to national resources such as the National Library Service for the Blind and Physically Handicapped. Conclusions – The web sites of urban public libraries are not yet completely accessible for persons with disabilities. At the very least they need coding fixes and ongoing maintenance to address the kinds of issues found by the online web evaluation tool used. In addition, resources for disabled persons should be prominently and clearly linked and promoted. Further research is called for, both in non-urban library systems and in testing a wider range of access technologies. Improvement efforts should acknowledge that web design that improves access for persons with disabilities serves the broader community as well.
APA, Harvard, Vancouver, ISO, and other styles
9

Król, Karol, and Dariusz Zdonek. "Initiatives to Preserve the Content of Vanishing Web Hosting." Sustainability 14, no. 9 (April 26, 2022): 5236. http://dx.doi.org/10.3390/su14095236.

Full text
Abstract:
Free hosting services have contributed to the development of the Internet or even acted as a catalyst thereof. This paper aims to answer the questions of what free hosting services represent for Internet users and why initiatives exist to archive content published on free servers. The empirical part of this study attempts to verify whether websites on free servers were designed in an archaic way, which could justify their discontinuation. Initiatives to preserve the content of vanishing web hosting sites are characterized based on a review of various source materials, including the academic literature and Internet resources. This empirical study involved 168 archaic websites, which were analyzed in three dimensions. Marketing components and design were assessed as well. Each assessment dimension was assigned diagnostic variables. The values of the diagnostic variables were standardized using zero unitarization. It was found that the owners of discontinued servers were not interested in creating and maintaining archives. Hence, numerous grassroots initiatives have emerged to salvage their content, although enthusiasm among the archive community seems to have dwindled. Many grassroots archives are available, but a considerable number are no longer supported. In this context, this paper proposes the term ‘vanishing hosting’. It provides a nostalgic and sentimental perspective on the termination of free hosting services. The authors noted that free hosting services have largely lost their past import. It is demonstrated that free servers traditionally hosted archaic websites, which justified their deletion from a business perspective. Moreover, the paper presents an outline of a method to revitalize the tourism sector based on changes brought about by global technology to the digital ecosystem. It is proposed that changes in search engine algorithms vicariously contribute to the revitalization of the tourism sector since they often drive the replacement of old websites with newer versions (latest technology and better quality). This leads to the improved online presentation of tourism service portfolios and the general quality of the content in search engine results.
APA, Harvard, Vancouver, ISO, and other styles
10

Journal, Baghdad Science. "Effective Rules for Building and Securing of Blogs." Baghdad Science Journal 6, no. 2 (June 7, 2009): 421–26. http://dx.doi.org/10.21123/bsj.6.2.421-426.

Full text
Abstract:
Blogging is about more than just putting thoughts on a web; it's about connecting with and hearing from anyone who read the work. Many web sites now days help to get a free account to quick post thoughts and photos interact with people, and more. The fastest way to understand blogging is to try it out, but in that case securing the blog is important, by including authentication schemes. In this paper we suggest implications of our research for improving the design and usefulness of blogging systems, and also we divided the blogs depending on the subject and need, which are either to be used in public or only used by small group, so we can suggest different steps for securing the blogs.
APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic "Web sites – Barrier-free design"

1

Gray, Andrea Edwards. "Virginia historic sites: are they accessible to the mobility impaired?" Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/43405.

Full text
Abstract:

The purpose of the study was to determine how historic organizations in Virginia have responded to the issue of handicapped accessibility at their properties. The study sought to determine which historic sites are accessible to the mobility impaired, what handicapped accessible features exist in the sites' buildings and what adaptations have been made to programs and activities taking place at the sites. The study also involved exploring reasons why some historic organizations have not made their buildings and programs accessible to the disabled and determining what future plans the historic organizations have for making their sites accessible to all people.

Questionnaires were sent to 228 historic sites in Virginia; 147 of the returned surveys met the research criteria. Even though most sites had at least one handicapped accessible feature, only 40 sites were reported to be accessible to everyone. Video-tours, slides and large photographs are made available to visitors who cannot participate in the entire tour at some of the historic sites. The main reasons historic organizations have not made their sites more accessible are that alterations are too expensive and structurally difficult. Forty-eight historic organizations plan to make their properties more accessible in the future.

A directory, containing a table of accessible features found at the sites, general tourist information and a description of programs available at the sites for the disabled, was compiled from the findings of this study.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Web sites – Barrier-free design"

1

Build a website for free. Indianapolis, Ind: Que Pub., 2009.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Build a website for free. 2nd ed. Indianapolis, Ind: Que Pub., 2011.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Wu zhang ai wang luo huan jing gou jian de li lun yu shi jian: Wuzhang'ai wangluohuanjinggoujian de lilun yu shijian. Beijing: Ke xue chu ban she, 2011.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Poor Richard's web site: Geek-free, commonsense advice on building a low-cost web site. Lakewood, CO: Top Floor Pub., 1998.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Nobles, Robin. Streetwise maximize web site traffic: Build web site traffic fast and free by optimizing search engine placement. Holbrook, Mass: Adams Media Corp., 2000.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Badger, Michael. Zenoss core 3.x network and system monitoring: A step-by-step guide to configuring, using, and adapting this free Open Source network monitoring system. Olton, Birmingham: Packt Pub., 2011.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Frazer, J. D. Money for content and your clicks for free: Turning Web sites, blogs, and podcasts into cash. Indianapolis, Ind: Wiley, 2006.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Frazer, J. D. Money For Content and Your Clicks For Free. New York: John Wiley & Sons, Ltd., 2007.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Inc, ebrary, ed. Zenoss Core network and system monitoring: A step-by-step guide to configuring, using, and adapting the free open-source network monitoring system. Birmingham, UK: Packt Publishing, 2008.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Lewandowski, Dirk, and Friederike Kerkmann. Barrierefreie Informationssysteme: Zugänglichkeit für Menschen mit Behinderung in Theorie und Praxis. Berlin: De Gruyter Saur, 2015.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Web sites – Barrier-free design"

1

Pieper, Michael, Renate Anderweit, Beate Schulte, Ulrike Peter, Jutta Croll, and Iris Cornelssen. "Methodological Approaches to Identify Honorable Best Practice in Barrier-Free Web Design." In User-Centered Interaction Paradigms for Universal Access in the Information Society, 360–72. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-540-30111-0_31.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Viganò, Paola, Bertrand Plewinski, Guillaume Vanneste, and Nicolas Willemet. "Peterbos: Living in the Park, Inhabiting the City." In The Urban Book Series, 155–74. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-19748-2_11.

Full text
Abstract:
AbstractThis paper explores the urban issues underlying the design experience in the Peterbos neighbourhood, Anderlecht, Brussels-Capital Region. It presents four themes, based on the living experiment of this urban project, which consists of a master plan for the renovation of public spaces (Studio Paola Viganò and vvv architecture urbanisme 2020). It starts with the critical perspective of a ‘project for the ground’. As an embodiment of modernity, collective living in high-rise buildings has made it possible to free up a large area of ground for use as a shared landscape. In Peterbos, this large ground has aged, deteriorated, and become disconnected from the city. Up until now, these characteristics have made Peterbos a place where all the ‘misery in the world’ (Bourdieu, La misère du Monde. Seuil, 1993) has been concentrated. A long transformation process is now underway: the renovation of housing and public spaces proposes new living conditions and a new image for the district. However, there are still questions about the appropriateness of such an investment in the absence of a radical rediscussing of what makes Peterbos an enclave for the poorest. Our analysis starts with the ground of Peterbos and its relationship with water flows, biodiversity, and the rest of the city. The modern project focuses on the liberation of the public ground. We see the Peterbos project as an opportunity for critical reinterpretation. Second, we reconsider the district’s position in the city and the need to reverse feelings inside and outside, aiming to renew relations with the metropolis. Third, a broader understanding of the environment is necessary in order to take part in an ecological transition. The notion of diversity and mixed-use as a fertile framework for emancipation and individual initiative is then discussed. Finally, in the conclusions, having explored the progetto di suolo as a manifold agent and pushed it to its limits, we conclude by examining the ‘stone guest’. Indeed, urbanism and investment in urban renewal do not represent an autonomous and self-responsible solution to the social and urban challenges society is currently facing. The design of public space represents a wide, but also a narrow, space for manoeuvre. When structural changes are implied, they do not tackle the basis of inequality concentrated at this site, linked to decisions made in the past that do not show the expected results. Interaction with economic policies is still too weak. We choose to use clear but sometimes burdensome vocabulary to discuss these spatial and social matters, not escaping the difficulty of the topic. All the same, urban and landscape designers have a responsibility and the possibility to assert the original meaning of politics as the organization of public life in the city, more broadly addressing actions in space and measures to reduce inequality and restore the dignity of the people who live there.
APA, Harvard, Vancouver, ISO, and other styles
3

Li, Rowena. "The Representation of National Political Freedom on Web Interface Design." In Interpersonal Relations and Social Patterns in Communication Technologies, 368–404. IGI Global, 2010. http://dx.doi.org/10.4018/978-1-61520-827-2.ch020.

Full text
Abstract:
The purpose of this chapter is to explore the representation of national political freedom on Web interface design by using power distance, one of the culture dimensions identified by Geert Hofstede, as a measurement. It also aims to determine if there are any differences between government-based Web sites and business-oriented Web sites in representing national political freedom. This study applied seven indicators validated from previous study (Li, 2009) in coding 312 Web sites selected from 39 countries and analyzed national political freedom represented on these Web sites with content analysis method. The result of two-way analysis of variance (ANOVA) indicated that large differences exist in Web interface design, which in turn reflects the aforementioned national political freedom. The research showed that the mean effect of freedom level between free-country group, partly-free-country group and not-free-country group was statistically significant (p = .003). So was the mean effect of Web site type between government-based and business-oriented Web sites (p = .000). Furthermore, the interaction between the freedom level and Web site type was also significant (p = .041). Therefore, we conclude that Web interface design correlates with a country’s political freedom level and government-based Web sites embody more of a nation’s authority and supremacy than business-oriented Web sites do. It is expected that this study furthers our exploration in culture dimensions on Web interface design and advances our knowledge in sociological and cultural studies of the Web.
APA, Harvard, Vancouver, ISO, and other styles
4

Jordan, Robert, Worachat Buranapunsri, and Zane Berge. "Sustaining Internet Accessibility." In Empowering Marginal Communities with Information Networking, 300–317. IGI Global, 2006. http://dx.doi.org/10.4018/978-1-59140-699-0.ch012.

Full text
Abstract:
In this chapter, accessibility is defined as providing barrier-free Internet applications for those with physical and other disabilities. In some nations, accessibility to government Web sites and Web-based applications is the law. In the private sector, providing accessible Web sites makes good business sense. It increases productivity of employees who use it, expands the markets of businesses that provide it, and enhances the reputation of organizations that employ it. Although there are cost and time challenges for Web designers who incorporate accessibility, these may be overcome through careful planning and a through understanding of accessible design principles. Accessible design means simple design, which benefits all users.
APA, Harvard, Vancouver, ISO, and other styles
5

Carr, James, and David Chadwick. "Research design." In An Introduction to Clinical Research. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199570072.003.0008.

Full text
Abstract:
From the outset, it’s worth highlighting that since the inception of the National Institute for Health Research (NIHR), specialist units now exist to promote good quality medical research by assisting in its design. In England, NIHR Research Design Services (RDS) have been commissioned in eight strategic health authority (SHA) regions, whilst the original Research and Development Support Units (RDSUs) in the other two SHA regions (North West and East Midlands) will continue to provide a similar service. The main purpose of these units is to help researchers develop and design high-quality research proposals for competitions for applied health or social care research. They have been developed with a focus on NHS based researchers applying to the NIHR Research for Patient Benefit Programme, however they also provide advice on other funding schemes. They are also supposed to off er access to a range of expertise in research design, including advice on research synthesis, study design and methodology (quantitative and qualitative), statistics, and economics, and to refer to other sources of expert advice on the applied health and social care research system. In summary these services should be a first port of call for most NHS-based researchers looking to develop a clinical research proposal into a substantial grant application. As many of the regional RDSs have only recently become operational, it is difficult to provide much information on how each RDS works. The general principle, however, is that these services should provide telephone, email, and face-to-face advice to researchers looking to develop a proposal. Many RDSs will provide face-to-face advice in hospitals across their region, or in other sites which should not be too far from where NHS staff are working. These services, which are free of charge, are provided by a variety of individuals with experience of NHS research, statistics, or health economics, some of whom will be active researchers who have been successful with grant applications. A telephone contact number or email address for each RDS can be obtained via the web link: http://www.nihrccf.org.uk/site/programmes/rds/default. cfm . Furthermore each RDS has a website which can be accessed via this link.
APA, Harvard, Vancouver, ISO, and other styles
6

Sharma, Vishal, and Rakhi Sharma. "Web Switching." In Enterprise Networking, 86–104. IGI Global, 2002. http://dx.doi.org/10.4018/978-1-930708-17-4.ch006.

Full text
Abstract:
Web switching may be viewed as an optimized combination of networking functions, such as load balancing, bandwidth and traffic management, cache switching, and site-level security, that are implemented on a single device and are specifically designed to address the unique requirements of World Wide Web (or simply, Web) traffic; for example, efficient management of Web traffic, simplified website management, and fast, reliable, and error-free website operation. More precisely, “Web switches are network devices that can be used to construct a ‘user- and content-aware’ network infrastructure, which has the explicit objective of seamless and high-performance routing of specific user requests for specific Web content to the best server containing that content, irrespective of its physical location (Johnson, 1999a).” A web switch, therefore, is an extremely fast and “intelligent” LAN switch that switches traffic based on content, rather than just addresses (Passmore, 1999), and integrates the traffic management and control functions that have traditionally run on a number of separate devices. These include sophisticated URL load balancing capabilities via local and global server load balancing, bandwidth control, network address translation (NAT), packet filtering, cache redirection, and policies to manage and speed the flow of web traffic.
APA, Harvard, Vancouver, ISO, and other styles
7

Davidson, Tatiana, Angela Moreland, Brian E. Bunnell, Jennifer Winkelmann, Jessica L. Hamblen, and Kenneth J. Ruggiero. "Reducing Stigma in Mental Health Through Digital Storytelling." In Research Anthology on Mental Health Stigma, Education, and Treatment, 909–19. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-8544-3.ch052.

Full text
Abstract:
The authors present the use of digital storytelling with two populations that have been consistently shown to be at increased risk for developing mental health disorders: veterans and firefighters. Despite efforts to increase access to evidence-based mental health programs, stigma remains a major barrier to care. AboutFace and Firefighters Helping Firefighters are two DST resources designed to help recognize the symptoms of posttraumatic stress disorder (PTSD) and related mental health symptoms, and to encourage help-seeking. These web-based video galleries introduce the viewer to 70+ peers who have experienced PTSD and have received formal treatment. These sites use the shared bonds of service to educate and help normalize common reactions that they may have due to the stressful nature of their occupations. Visitors to the site can “meet” peers and hear how mental illness has affected them through unscripted, authentic personal stories and can learn about common symptoms, struggles regarding decisions to seek care, and detailed descriptions of what treatment was like.
APA, Harvard, Vancouver, ISO, and other styles
8

Giuseppe, Sindoni, and Tininini Leonardo. "Statistical Dissemination Systems and the Web." In Handbook of Research on Public Information Technology, 578–91. IGI Global, 2008. http://dx.doi.org/10.4018/978-1-59904-857-4.ch053.

Full text
Abstract:
The Web is increasingly used as a preferred medium for A2C (administration to citizens) and A2B (administration to business) service delivery. An increasing number of government initiatives are aimed at making access to electronic records easier for the general public. For example, the Electronic Record Archives program of the U.S. National Archives and Records Administration is aimed at preserving virtually any kind of electronic record, free from dependence on any specific hardware or software, and at enabling customers to find records they want and to deliver those records in formats suited to customers’ needs (Lake, 2006). This in particular will include records coming from the 2010 U.S. census. International professional associations are increasingly paying attention to public availability of statistical data. For example, the last meeting of the International Association for Social Science Information Services & Technology (IASSIST, 2006) dedicated entire sessions to problems like knowledge and resource discovery, innovative data dissemination systems, and data-intensive Web site design.
APA, Harvard, Vancouver, ISO, and other styles
9

Baker, J. "Queendom Online Test Repository." In Handbook of Research on Electronic Surveys and Measurements, 352–54. IGI Global, 2007. http://dx.doi.org/10.4018/978-1-59140-792-8.ch049.

Full text
Abstract:
According to Barak and English (2002), the use of Internet-based psychological tests is an extension of computerized testing which emerged in the 1980s (p. 65). As with computerized testing, online psychological tests provide almost instant results since Likert-style questions can be scored by the computer without additional human intervention. Additionally, customized profiles can be presented along with the resulting scores, enabling the user to draw additional meaning from the selected instrument. An additional benefit of Internet-based measures is the potential for web sites to serve as clearinghouses containing a myriad of instruments, available to online users for free or on a subscription basis. As a result, numerous online repositories have been developed which offer a variety of psychological tests, ranging from fully validated instruments to individually-designed scales. One of the more popular test libraries is the Queendom.com site run by Plumeus, Inc. Since its founding in 1996, over 90 million people have completed over 400 million tests in nine different languages at the Queendom web site (http://www.queendom.com). According to the Queendom home page, the site contains “114 professionally developed and validated psychological tests, 111 Just-for-Fun tests, [and] 230 mind games and quizzes.” The five most popular psychological tests are the Classical Intelligence Test, the Self-Esteem Test, the Emotional Intelligence Test, the Communication Skills Test, and the Type-A Personality Test. Just-for-Fun test include such measures as the Snob Test, the Blind Date Test, and the Party Guest Test. Mind games and quizzes include puzzles, math problems, memory games, and trivia tests.
APA, Harvard, Vancouver, ISO, and other styles
10

Chen, Lei-da, and Gordon W. Skelton. "Mobile Application Development I." In Mobile Commerce Application Development, 228–69. IGI Global, 2005. http://dx.doi.org/10.4018/978-1-59140-806-2.ch009.

Full text
Abstract:
Microsoft Embedded Visual Tools were designed to develop applications that run on Windows CE devices (e.g., Pocket PC and Handheld PC 2000). It is a free software product that can be downloaded at the www.microsoft.com Web site. Two programming languages are supported by Microsoft Embedded Visual Tools: Embedded Visual Basic (eVB) and Embedded Visual C++ (eVC). These two programming languages are versions of Visual Basic and Visual C++ with limited capabilities, respectively. Therefore, developers with Visual Basic or Visual C++ experience can easily leverage their existing expertise to develop mobile or wireless applications. Since many developers are familiar with Visual Basic, we will explore the techniques of using eVB to develop applications for wireless devices in this chapter.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Web sites – Barrier-free design"

1

Wang, Shao-Feng. "Research on Web Interface barrier-free Design for Elderly People." In 2020 International Conference on Intelligent Design (ICID). IEEE, 2020. http://dx.doi.org/10.1109/icid52250.2020.00040.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Sugahara, Masashi, Keichi Noto, Atsushi Idoji, Kazukiyo Yamamoto, Kenta Hanai, and Takeo Kondo. "A User Evaluation Study on the Universal Network of the Water Transportation in the Seto Inland Sea in Japan." In ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-50084.

Full text
Abstract:
As Japan has increasingly becoming a so-called “super-aging society,” and the number of people with mobility impairment has increased, the barrier-free improvements have been implemented to public facilities so far. After the New Barrier-free Law has been enforced, however, the conceptual basis of such improvements has been shifting toward the universal design, based on the idea that everybody should be able to use facilities impartially. This study clarifies the present situation and problems of the barrier-free improvements from a passenger ship terminal to the inside of a ship, and elucidates improvement issues of nodal points of future marine and land transport. We carried out a questionnaire and site survey for the Hiroshima Port Ujina Passenger Boat Terminal, as well as the ships used, where the improvements are made based on the New Barrier-free Law.
APA, Harvard, Vancouver, ISO, and other styles
3

Kanai, Satoshi, Hidetomo Takahashi, and Takeshi Kishinami. "Networked Haptic Interfaces for Distant Redesign and Review of Free-Form Surfaces." In ASME 1997 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/detc97/dfm-4366.

Full text
Abstract:
Abstract The review and redesign of a freeform surface model, a process known as approval, is the final and indispensable stage in advancing a model from style designer to die manufacturer. This paper proposes a collaborative system for the review, redesign, and exchange of data on freeform surface models over a network, with the goal of improving the efficiency of the approval process among distant sites. First we analyze the work-flow of the long-distance approval. Then, in order to eliminate the physical model, we present a 3DOF haptic interface (force display) that accurately renders the feel of the freeform surface in great detail. Finally, we describe the architecture of the intra-network software that manages each step of the approval while maintaining consistency between the numerous versions of the surface models. The experimental results of a 3DOF communication between Tokyo and Sapporo and the subsequent review and redesign of the system are also shown.
APA, Harvard, Vancouver, ISO, and other styles
4

Campbell, Etse-Oghena Y., Fang-Chi Hsu, and Christopher G. Rylander. "Evaluating The Dispersal Volume of a Six-Port Arborizing Catheter in Agarose as a Function of Infusion Flow Rate and Catheter Retraction Speed." In 2022 Design of Medical Devices Conference. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/dmd2022-1057.

Full text
Abstract:
Abstract Convection-enhanced delivery (CED) is an emerging method for treating highly aggressive and infiltrative forms of brain cancer, like glioblastomas. However, drawbacks of utilizing CED include limited availability of tools capable of bypassing the blood-brain barrier and blood-brain tumor barrier to deliver therapeutics to saturate the tumor and adjacent tumor periphery where highly infiltrative glioma cells may be located. The consequence is that tumor recurrence at or near the original tumor site is inevitable. The Convection-Enhanced Thermo-Therapy Catheter System (CETCS) is a remote-operable device comprising of an arborizing catheter and therapeutic delivery control system designed to maximize the distribution of therapeutics in target tissue volumes. In this study, we evaluate the performance of the CETCS in agarose gel brain tissue phantoms while monitoring the volume of infusate delivered, the dispersal volume of the infusate, and the mean distribution ratio of infusate. We report high infusion flow rates increase infusate dispersal volume but can result in backflow up the microneedles tracts; constant microneedle retraction maximizes infusate dispersal volume; and finally, low infusion flow rates resulted in better control of infusion cloud shape and minimized occurrence of backflow along microneedles.
APA, Harvard, Vancouver, ISO, and other styles
5

Deng, Yih-Charng, Julie Peng, and Prabhu Setru. "Side Airbag Design Using an Enhanced MADYMO SID Model." In ASME 1998 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/imece1998-0976.

Full text
Abstract:
Abstract In this study, we evaluated and enhanced a SID model in the MADYMO database. It was found that the original MADYMO model exhibited discrepancies with the SID responses measured from the barrier impact test. After a number of improvements were made to the thorax region the revised model showed better correlation with the test results. Design exercises were performed using the SID model to study the design of a side airbag for a large car, including the effects of different sizes for the vent, inflator and bag. Occupant responses indicated that a large vent is beneficial whereas low sensitivities were found for the inflator and bag size variations.
APA, Harvard, Vancouver, ISO, and other styles
6

Azrar, L., R. Benamar, and M. Potier-Ferry. "Coupling Finite Element Method and Perturbation Techniques for Non Linear Vibrations of Plates." In ASME 1999 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/detc99/vib-8003.

Full text
Abstract:
Abstract The effectiveness of the coupling of the perturbation techniques and the finite element method has been demonstrated using a method called Asymptotic-Numerical Method (ANM). This concept eliminates the major difficulties of the classical perturbation methods namely the complexity of the right hand sides and the limitation of the validity of the solution obtained. In this paper we present the development of this method and its applicability for large amplitudes free vibrations of plates. The displacement and the frequency are expanded into power series with respect to a control parameter. The nonlinear governing equation is transformed into a sequence of linear problems having the same stiffness matrix. Needing one matrix inversion, a large number of terms can be computed with a small computation time. Taking the starting point in the zone of validity, the method is reapplied in order to determine a further part of the nonlinear solution. In order to increase the zone of validity, the Pade approximants are incorporated. Iterations of this method lead to a powerful incremental method. Numerical tests for large amplitudes free vibrations of plates with various shapes and boundary conditions are reported. Recent improvements in the basic ANM algorithm as well as applications to various structural problems are added in order to exhibit the effectiveness and the applicability of this method.
APA, Harvard, Vancouver, ISO, and other styles
7

Garcia Vargas, Joel A., and Antonio Ruvalcaba Gonza´lez. "Probabilistic Estimation in Soil Dynamic Properties to Obtain Response Spectra at Campeche Bay." In ASME 2003 22nd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2003. http://dx.doi.org/10.1115/omae2003-37259.

Full text
Abstract:
In the present study, response spectra for seismic design in the Bay of Campeche for offshore platforms, using probabilistic models in soil dynamic properties (shear modulus “G”, normalized shear modulus “G/Gmax” and damping ratio “D”), to evaluate their influence in the response of the site of interest, are presented. In this study the probabilistic model of the soil, take into account the uncertainty in soil dynamic properties, due to the fact that the soil dynamic properties play an important role on the interpretation of free-field motion. In this work an explicit form of the seismic wave characteristics were supposed and their likely source-site propagation characteristics were performed with two computer programs. In order to obtain seismic design parameters, three types of seismic event records were associated to the soil properties at the site of interest, taking into account local effect conditions. Geothechnical, seimologycal, tectonical and geological information, similar to the area of interest, were used. The maximum acceleration on the surface, the soil dominant period of vibration, the duration and the frequency content due to a dynamic excitation applied in the rigid base of the soil column were considered. We assumed that each one of the three types of earthquakes are representative of strong motions that might be potentially affecting the Bay of Campeche. In the study thirty-one sampling in several sites located at the Bay of Campeche were used as well as field and laboratory tests. The dynamic properties were determined in each test type by different ranges according to their shearing strain. From these results test, we know the G and D variation law in the range of interest. In the same way, the uncertainty level influence of the soil dynamic properties was modeled with the expected value of the soil dynamic properties. Six different sets including the soil modulus plus/minus a standard deviation, coefficient from the dynamic properties-time variant evaluations, for each one of the shearing strain, which are contained between 10−4 a 10, were considered. Expected site response spectra for different recurrence periods, may be used to complement available information in order to update the present seismic design spectra for offshore facilities located in this area.
APA, Harvard, Vancouver, ISO, and other styles
8

Imanishi, Ken, Hajime Nomura, Mitsuo Ebisawa, Katsuyuki Tsuji, and Shinichi Enoki. "Melting/Solidification Analysis of the Pb Free-Solder in Sleeve Soldering." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-51253.

Full text
Abstract:
Automatic soldering technic called Sleeve soldering has been developed recently. In the technic, a ceramic tube has been used instead of a soldering iron. It is called Sleeve. Fixed amount of solder is loaded into this Sleeve. The melted solder is poured from tip of the Sleeve to glue electronic parts into electronic boards. At present Sleeve soldering has been produced and introduced. However condition of soldering failure and concept of process design are not clear due to a few data of melting behavior and solidification. In this research we intended to express these standards by comparing numerical analysis and experiment. Moreover we explain about the establishment of numerical analysis method in this paper. Result in the behavior using the solder model has been similar to actual phenomenon in this simulation. Besides, we have confirmed that the fillet and back fillet was arisen on both sides of the electronic board.
APA, Harvard, Vancouver, ISO, and other styles
9

Wang, Jungao, Rajeev Kumar Jaiman, Peter Francis Bernad Adaikalaraj, Linwei Shen, Sue Ben Tan, and Wenping Wang. "Vortex-Induced Vibration of a Free-Hanging Riser Under Irregular Vessel Motion." In ASME 2016 35th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/omae2016-54701.

Full text
Abstract:
In this paper, we focus on vortex-induced vibration (VIV) of a free-hanging riser attached to a vessel under irregular wave conditions. The global in-plane responses of the hanging riser are firstly studied numerically in order to generate the equivalent current profile under vessel motion, and a simplified irregular vessel motion-induced VIV prediction methodology is then proposed based on the understanding from previous experimental observations and literature review. Further comparison on irregular vessel motion-induced VIV and ocean current-induced VIV at the same operation site with the same return period is performed to emphasize the importance of vessel motion-induced VIV. Numerical results highlight that vessel motion-induced VIV can cause similar stresses, fatigue damage and drag amplification similar to the steady ocean current cases, especially to the operation site like Norwegian Sea where strong wave field exists with mild current condition. It should be mentioned that although the simplified methodology proposed in this paper requires further experimental validation, it is believed that the presented numerical pre-study would help the industry and the researchers to have initial understanding on the possible occurrence of vessel motion-induced VIV. We further show the similarities and differences of vessel motion-induced VIV with respect to the ocean current-induced VIV and its implications on riser design and operation.
APA, Harvard, Vancouver, ISO, and other styles
10

Aghilinejad, Arian, Christopher Landry, George Cha, and Xiaolin Chen. "Enhancing the Cell Viability in High Throughput Deterministic Lateral Displacement Separation of Circulating Tumor Cells." In ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-10209.

Full text
Abstract:
Abstract Cancer is among a major health concerns all over the world. Cancer metastasis, which defines as the migration of malignant cells from original sites to distant organs, is the main reason of death due to cancer and there is growing evidence that Circulating Tumor Cells (CTCs) are responsible for initiating the metastasis. Due to the importance of these bioparticles in biotechnology and medicine, there is a growing interest to study and separate them through different techniques especially microfluidic label-free technologies. One such technology, termed Deterministic Lateral Displacement (DLD) has recently shown promising abilities to separate cells and particles of different sizes. However, DLD is a separation method that takes advantages of the predictable flow laminae of low Reynolds number (Re) fluid flow. In order to achieve higher device throughput, effects of higher Reynolds number flow on DLD device should be studied. Additionally, the higher flow rates would apply higher forces and shear stresses on the cells which threaten the cell’s viability. In this study, employing numerical simulation, the effect of high Re number on DLD device for separating cancer cells has been investigated. Specifically, we conducted force analysis and by focusing on the downstream gap distance between the posts, we improved the device which results in less cell deformation. Our developed numerical model and presented results lay the groundwork for design and fabrication of high-throughput DLD microchips for enhanced separation of CTCs.
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Web sites – Barrier-free design"

1

Rusk, Todd, Ryan Siegel, Linda Larsen, Tim Lindsey, and Brian Deal. Technical and Financial Feasibility Study for Installation of Solar Panels at IDOT-owned Facilities. Illinois Center for Transportation, August 2021. http://dx.doi.org/10.36501/0197-9191/21-024.

Full text
Abstract:
The Smart Energy Design Assistance Center assessed the administrative, technical, and economic aspects of feasibility related to the procurement and installation of photovoltaic solar systems on IDOT-owned buildings and lands. To address administrative feasibility, we explored three main ways in which IDOT could procure solar projects: power purchase agreement (PPA), direct purchase, and land lease development. Of the three methods, PPA and direct purchase are most applicable for IDOT. While solar development is not free of obstacles for IDOT, it is administratively feasible, and regulatory hurdles can be adequately met given suitable planning and implementation. To evaluate IDOT assets for solar feasibility, more than 1,000 IDOT sites were screened and narrowed using spatial analytic tools. A stakeholder feedback process was used to select five case study sites that allowed for a range of solar development types, from large utility-scale projects to small rooftop systems. To evaluate financial feasibility, discussions with developers and datapoints from the literature were used to create financial models. A large solar project request by IDOT can be expected to generate considerable attention from developers and potentially attractive PPA pricing that would generate immediate cash flow savings for IDOT. Procurement partnerships with other state agencies will create opportunities for even larger projects with better pricing. However, in the near term, it may be difficult for IDOT to identify small rooftop or other small on-site solar projects that are financially feasible. This project identified two especially promising solar sites so that IDOT can evaluate other solar site development opportunities in the future. This project also developed a web-based decision-support tool so IDOT can identify potential sites and develop preliminary indications of feasibility. We recommend that IDOT begin the process of developing at least one of their large sites to support solar electric power generation.
APA, Harvard, Vancouver, ISO, and other styles
2

Hunter, Martha S., and Einat Zchori-Fein. Rickettsia in the whitefly Bemisia tabaci: Phenotypic variants and fitness effects. United States Department of Agriculture, September 2014. http://dx.doi.org/10.32747/2014.7594394.bard.

Full text
Abstract:
The sweet potato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) is a major pest of vegetables, field crops, and ornamentals worldwide. This species harbors a diverse assembly of facultative, “secondary” bacterial symbionts, the roles of which are largely unknown. We documented a spectacular sweep of one of these, Rickettsia, in the Southwestern United States in the B biotype (=MEAM1) of B. tabaci, from 1% to 97% over 6 years, as well as a dramatic fitness benefit associated with it in Arizona but not in Israel. Because it is critical to understand the circumstances in which a symbiont invasion can cause such a large change in pest life history, the following objectives were set: 1) Determine the frequency of Rickettsia in B. tabaci in cotton across the United States and Israel. 2) Characterize Rickettsia and B. tabaci genotypes in order to test the hypothesis that genetic variation in either partner is responsible for differences in phenotypes seen in the two countries. 3) Determine the comparative fitness effects of Rickettsia phenotypes in B. tabaci in Israel and the United States. For Obj. 1, a survey of B. tabaci B samples revealed the distribution of Rickettsia across the cotton-growing regions of 13 sites from Israel and 22 sites from the USA. Across the USA, Rickettsia frequencies were heterogeneous among regions, but were generally at frequencies higher than 75% and close to fixation in some areas, whereas in Israel the infection rates were lower and declining. The distinct outcomes of Rickettsia infection in these two countries conform to previouslyreported phenotypic differences. Intermediate frequencies in some areas in both countries may indicate a cost to infection in certain environments or that the frequencies are in flux. This suggests underlying geographic differences in the interactions between bacterial symbionts and the pest. Obj. 2, Sequences of several Rickettsia genes in both locations, including a hypervariableintergenic spacer gene, suggested that the Rickettsia genotype is identical in both countries. Experiments in the US showed that differences in whitefly nuclear genotype had a strong influence on Rickettsia phenotype. Obj. 3. Experiments designed to test for possible horizontal transmission of Rickettsia, showed that these bacteria are transferred from B. tabaci to a plant, moved inside the phloem, and could be acquired by other whiteflies. Plants can serve as a reservoir for horizontal transmission of Rickettsia, a mechanism that may explain the occurrence of phylogenetically-similarsymbionts among unrelated phytophagous insect species. This plant-mediated transmission route may also exist in other insect-symbiont systems, and since symbionts may play a critical role in the ecology and evolution of their hosts, serve as an immediate and powerful tool for accelerated evolution. However, no such horizontal transmission of Rickettsia could be detected in the USA, underlining the difference between the interaction in both countries, or between B. tabaci and the banded wing whitefly on cotton in the USA (Trialeurodes sp. nr. abutiloneus) and the omnivorous bug Nesidiocoristenuis. Additionally, a series of experiments excluded the possibility that Rickettsia is frequently transmitted between B. tabaci and its parasitoid wasps Eretmocerusmundus and Encarsiapergandiella. Lastly, ecological studies on Rickettsia effects on free flight of whiteflies showed no significant influence of symbiont infection on flight. In contrast, a field study of the effects of Rickettsia on whitefly performance on caged cotton in the USA showed strong fitness benefits of infection, and rapid increases in Rickettsia frequency in competition population cages. This result confirmed the benefits to whiteflies of Rickettsia infection in a field setting.
APA, Harvard, Vancouver, ISO, and other styles
3

Yogev, David, Ricardo Rosenbusch, Sharon Levisohn, and Eitan Rapoport. Molecular Pathogenesis of Mycoplasma bovis and Mycoplasma agalactiae and its Application in Diagnosis and Control. United States Department of Agriculture, April 2000. http://dx.doi.org/10.32747/2000.7573073.bard.

Full text
Abstract:
Mycoplasma bovis and M. agalactiae are two phylogenetically related mycoplasmas which cause economically significant diseases in their respective bovine or small ruminant hosts. These organisms cause persistent asymptomatic infections that can result in severe outbreaks upon introduction of carrier animals into susceptible herds. Little is known about the mechanisms underlying mycoplasma-host interaction, variation in virulence, or of the factors enabling avoidance of the host immune system. In recent years it has become apparent that the ability of pathogenic microorganisms to rapidly alter surface antigenic structures and to fine tune their antigenicity, a phenomena called antigenic variation, is one of the most effective strategies used to escape immune destruction and to establish chronic infections. Our discovery of a novel genetic system, mediating antigenic variation in M. bovis (vsp) as well as in M. agalactiae (avg) served as a starting point for our proposal which included the following objectives: (i) Molecular and functional characterization of the variable surface lipoproteins (Vsp) system of M. bovis and comparison with the Vsp-counterpart in M. agalactiae (ii) Determination of the role of Vsp proteins in the survival of M. bovis when confronted by host defense factors, (iii) Assessment of Vsp-based genetic and antigenic typing of M. bovis and M. agalactiae for epidemiology of infection and (iv) Improvement of diagnostic tests for M. bovis and M. agalactiae based on the vsp-and vsp-analogous systems. We have carried out an extensive molecular characterization of the vsp system and unravelled the precise molecular mechanism responsible for the generation of surface antigenic variation in M. bovis. Our data clearly demonstrated that the two pathogenic mycoplasma species possess large gene families encoding variable lipoprotein antigens that apparently play an important role in immune evasion and in pathogen-host interaction during infection. Phase variable production of these antigens was found to be mediated by a novel molecular mechanism utilizing double site-specific DNA inversions via an intermediate vsp configuration. Studies in model systems indicate that phase variation of VspA is relevant in interaction between M. bovis and macrophages or monocytes, a crucial stage in pathogenesis. Using an ELISA test with captured VspA as an antigen, phase variation was shown to occur in vivo and under field conditions. Genomic rearrangements in the avg gene family of M. agalactiae were shown to occur in vivo and may well have a role in evasion of host defences and establishment of chronic infection. An epidemiological study indicated that patterns of vsp-related antigenic variation diverge rapidly in an M. bovis infected herd. Marked divergence was also found with avg-based genomic typing of M. agalactiae in chronically infected sheep. However, avg-genomic fingerprints were found to be relatively homogeneous in different animals during acute stages of an outbreak of Contagious Agalactiae, and differ between unrelated outbreaks. These data support the concept of vsp-based genomic typing but indicate the necessity for further refinement of the methodology. The molecular knowledge on these surface antigens and their encoding genes provides the basis for generating specific recombinant tools and serological methods for serodiagnosis and epidemiological purposes. Utilization of these methods in the field may allow differentiating acutely infected herds from chronic herds and disease-free herds. In addition the highly immunogenic nature of these lipoproteins may facilitate the design of protective vaccine against mycoplasma infections.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography