The classical theory of univalent functions and quasistatic crack propagation

We study the propagation of a crack in critical equilibrium for a brittle material in a Mode III field. The energy variations for small virtual extensions of the crack are handled in a novel way: the amount of energy released is written as a functional over a family of univalent functions on the upper half plane. Classical techniques developed in connection to the Bieberbach Conjecture are used to quantify the energy-shape relationship. By means of a special family of trial paths generated by the so-called Löwner equation we impose a stability condition on the field which derives in a local crack propagation criterion. We called this the anti-symmetry principle, being closely related to the well known symmetry principle for the in-plane fields

Displaying the Past: Guidelines for Outreach Using Archival Collections

In the summer of 2017, our community college library had the opportunity to partner with a local historical society to produce an exhibit about the history of the college in the historical society’s welcome center. With no dedicated archivist or outreach librarian, two research and instruction librarians with archives experience from previous employment were tasked with leading and implementing this project with little precedent. Our archive is relatively new, and still in the early stages of development. Most collections are minimally processed and no electronic finding aids exist to aid in search and retrieval efforts. Additionally, with limited display space of our own, archival display materials are limited. In order to design this exhibit, the librarians had to inventory and identify potential archival sources for display, address preservation concerns, obtain display equipment, coordinate installation with the historical society, work with college public relations and plan an opening reception. With future outreach exhibits planned, we wanted to use what we learned in the process to make subsequent outreach exhibits easier to plan and execute. This poster will provide attendees with a list of guidelines to consider when creating an exhibit with an external partner based on what was learned as we worked through the exhibit making process. While the exhibit was an overall success, there were many bumps in the road and lessons learned to share with conference goers. Attendees will walk away with an understanding of pitfalls to avoid as well as recommended best practices for librarians using an exhibit for outreach. This poster presentation will also demonstrate that librarians should not let inexperience or minimally processed collections be a barrier to establishing meaningful community connections

On the Divergence of Perturbation Theory: Steps Towards a Convergent Series

The mechanism underlying the divergence of perturbation theory is exposed. This is done through a detailed study of the violation of the hypothesis of the Dominated Convergence Theorem of Lebesgue using familiar techniques of Quantum Field Theory. That theorem governs the validity (or lack of it) of the formal manipulations done to generate the perturbative series in the functional integral formalism. The aspects of the perturbative series that need to be modified to obtain a convergent series are presented. Useful tools for a practical implementation of these modifications are developed. Some resummation methods are analyzed in the light of the above mentioned mechanism

Los ensanches del muelle nuevo de Portugalete : 1869-1917

Portugalete era en 1850 una pequeña villa medieval costera que conservaba el trazado originario. Al no poder expandirse por el nucleo primitivo, por motivos de situación, se inicia la extensión de la ciudad a través de los terrenos arenales que se sitúan en el muelle. El artículo analiza los dos planes de ensanche que se ejecutaron en 1869-1872 y 1904-1917 respectivament

Espelhos étnicos. Autorrepresentações em museus galeses e menonitas na Argentina e no Paraguai

According to some scholars and philosophers, ethnic identities are the best political, social, economic, ethic (and even aesthetic) alternative to State centralism, which is incapable of dealing with cultural diversity. Ethnic communitarism is then defined as a more authentic, humane, democratic and inclusive form of organization. The Welsh colonies of Chubut (Argentine) and the established Mennonite colonies of the Chaco Region (Paraguay) are two ethnic groups with forms of community life that have been thoroughly studied from different perspectives. However, neither has been analyzed their point of view of alterity or their relation with those who do not belong to the community. In their museums the history of the community is represented, self-images and other people's images are constructed and spread. The interesting part of these stories is not what they say but what they do, the form in which contents are expressed. These communitarian historical museums tell about the past but they mainly have an impact on the present. Like national or even imperial museums, Welsh and Mennonite museums tend to naturalize a particular self-centered, prejudicial and evolutionist point of view that often excludes other perspectives, especially those elaborated by the neighboring indigenous communities. In contrast, we believe it is necessary to take a stance for democratic, horizontal relations between communities and more polyphonic and responsible historical representations.Alguns filósofos e acadêmicos assinalam que as identidades étnicas são a melhor alternativa política, social, econômica, ética (e mesmo estética) ao centralismo estatal, que é negligente ao lidar com a diversidade cultural. O comunitarismo étnico é definido como uma forma de organização mais autêntica, humana, democrática e inclusiva. As colônias galesas de Chubut (Argentina) e as colônias rurais dos menonitas no Chaco (Paraguay) são dois grupos étnicos cujas vidas comunitárias têm sido muito estudadas desde diversas perspectivas, mas o seu ponto de vista acerca da alteridade ou sua relação com os atores extracomunitários nunca foi levado em conta. A historia comunitária é representada nos museus galeses e menonitas das respectivas regiões e aí são construídas e difundidas não só as autoimagens mas também as representações dos outros. O aspecto relevante dessas histórias não é o que elas dizem, mas o que fazem, a forma como os conteúdos são expressos. Esses museus históricos comunitários falam sobre o passado, mas seu maior impacto recai sobre o presente. Como os museus nacionais ou imperiais, os museus galeses e menonitas tentam naturalizar pontos de vista particulares, auto-centrados, preconceituosos e evolucionistas que geralmente excluem as perspectivas elaboradas pelas comunidades indígenas vizinhas. Em vez disso, pensamos ser necessário criar relações mais horizontais e democráticas entre as comunidades e difundir representações históricas mais polifônicas e responsáveis

Portugalete, villa medieval : urbanismo y arquitectura, 1322-1500

En este artículo se analiza el proceso urbanístico medieval de la villa de Portugalete y las realizaciones arquitectónicas más destacadas en los campos de la arquitectura religiosa, de servicios y privadaArtikulu honetan Portugalete hiriko Behe Hartarako Garapen arkitektonikoa eta arkitektura erlijioso, pribata zein publikoko obrarik nabarmenak ditugu aztergaiDans cet article, on étudie I'urbanisme du XIV et XV'ème siècles de la ville de Portugalete et les bâtiments plus importants de I'architecture religieus

The management of Natura 2000 Network sites: a discrete choice experiment approach

One of the main problems that public institutions face in the management of protected areas, such as the European Natura 2000 network, is how to design and implement sustainable management plans accounting both for the social cost and benefits of conserving these sites. This paper provides with an empirical application of a discrete choice experiment undertaken in a Natura 2000 site in the Basque Country (Spain) aimed at evaluating the social preferences for different land-use options. This information is then used to evaluate the social desirability of some future management plans.environmental valuation, discrete choice experiments, choice modelling, Natura 2000