The behaviour of a two-component backfilling grout used in a Tunnel-Boring Machine

The instantaneous filling of the annulus that is created behind the segment lining at the end of the tail during the TBM advance is an operation of paramount importance. Its main goal is to minimize the surface settlements due to any over-excavation generated by the passage of the TBM. To correctly achieve the goals, a simultaneous backfilling system and the injected material should satisfy the technical, operational and performance characteristics. A two-component system injection for the back-filling is progressively substituting the use of traditional mortars. In this paper different systems of back-filling grout and in particular the two-component system are analyzed and the results of laboratory tests are presented and discusse

"No Disease for the Others": How COVID-19 data can enact new and old alterities

The COVID-19 pandemic invites a question about how long-standing narratives of alterity and current narratives of disease are entwined and re-enacted in the diagnosis of COVID-19. In this commentary, we discuss two related phenomena that, we argue, should be taken into account in answering this question. First, we address the diffusion of pseudoscientific accounts of minorities' immunity to COVID-19. While apparently praising minorities' biological resistance, such accounts rhetorically introduce a distinction between "Us" and "Them," and in so doing produce new and re-enact old narratives of alterity. Second, these unsubstantiated narratives thrive on fake news and scarcity of data. The second part of this commentary thus surveys the methods through which the COVID-19 test is administered in various countries. We argue that techniques used for data collection have a major role in producing COVID-19 data that render contagion rates among migrants and other minorities invisible. In the conclusion, we provide two recommendations about how COVID-19 data can instead potentially work towards inclusion

Securitizing the infrastructural Europe, infrastructuring a securitized Europe

This book explores the processes and practices of the securitization and de-securitization of European infrastructures and how political institutions interact with security and insecurity. Expert contributors address distinct areas, from border politics and biosecurity to health governance and law and border control enforcement, to examine the various ways in which infrastructures are envisioned, designed, negotiated and built. They explore how ‘infrastructuring’ contributes to emergent forms of European identity, integration, and statehood. The book will appeal to scholars and students of Science and Technology Studies, Political Sociology, Critical Security Studies, International Relations, European Integration Studies, Infrastructure Studies, or Critical Border and Migration Studies

Tracing back Communities. An Analysis of Ars Electronica's Digital Communities archive from an ANT perspective

Since long before the popularization of the Web, community-making has been a significant driving force for the development of the Internet. As a consequence, in mid 1990s online communities became a key object of study at the intersection of social sciences, organizational studies and computer sciences. Today, about fifteen years after these early studies, the concept \u2018online community\u2019 seems to be at stake. As a matter of fact, while communitarian ties enabled by digital media are more and more invocated, in late 2000s the Internet is revealing itself as a much more bureaucratic and profit-oriented domain than ever, to the point that it is not clear whether there exist online ties that are specific enough to be called \u2018communitarian\u2019. In order to analyse such an opaque and unstable object of study as current techno-social assemblages, innovative methods specifically developed to study fuzzy objects have to be devised and some epistemological questions have to be addressed. This research starts indeed from the impasse that the digital communitarian culture is experiencing at the end of the 2000s and borrows some epistemological insights from the Actor-Network Theory. By analyzing the entry forms submitted to the world\u2019s leading competition for digital communities, Prix Ars Electronica, this research thus calls into question some \u2018black-boxed\u2019 concepts like \u2018cyberculture\u2019, \u2018digital revolution\u2019, \u2018empowerment\u2019 and \u2018online community\u2019 itself. On one hand, the results bring into question both leading sociological positions and hype-generated commonplaces. On the other hand, the results offer evidence to those arguments according to which current ICT developments represent the beginning of a new phase of technological enclosure

Computational modelling of the effect of surfaces on polyvinyldenedifluoride

The physical properties of polyvinyldenediluoride (PVDF) polymorphs and the effect of surfaces on PVDF properties have been investigated with computational modelling to address crystallinity issues that such semi-crystalline polymer presents. Indeed, PVDF has the potential to support new technology generation of lexible electronic devices, but to preparere liable devices made with PVDF, such polymer needs to be sampled at high crystalline grade.;As PVDF is a semi-crystalline polymer its intrinsic lexibility represents a major advantage for lexible electronics which also increases manufacturing complexity of such material. To understand the crystalline behaviour of PVDF it is necessary to computationally investigate its fundamental physical properties per each of its crystal phase and the main behaviour of PVDF in conditions of inite temperature.;Density functional theory (DFT) calculations has been used as a quantum mechanical (QM) tool to solve the electronic structures of PVDF polymorphs obtaining structural information such as geometries, energetics, spontaneous polarisation and vibrational frequencies. Furthermore the impact of including van derWaals (vdW) forces in DFT was evaluated showing that the vdW-DF DFT functional had the best physical properties prediction agreement with experimental observations.;The vibrational frequencies of all PVDF polymorphs were computationally determined to verify the metastability of every crystal phase determined in the present study. Furthermore, the vibrational frequencies determination allowed to enrich the knowledge about adsorption peaks that each PVDF structure possesses to ease the computation to experimental IR spectra comparison.;The optimised geometries of PVDF crystals obtained from the DFT investigation have been scaled to molecular dynamics (MD) since it represents a time consistent methodology to follow the evolution of molecular interactions between particles. The interest was to compute the inite temperature dynamics, ensuring the use of the best performing force field and to gather new knowledge about the crystalline phase formation of PVDF liquid melts under different conditions such as bulk and confined between surface layers.;The effect of polymer confinement and surface/polymer electrostatics interaction were evaluated in such study showing that electrostatics played a main role in driving the formation of highly crystalline PVDF systems.The physical properties of polyvinyldenediluoride (PVDF) polymorphs and the effect of surfaces on PVDF properties have been investigated with computational modelling to address crystallinity issues that such semi-crystalline polymer presents. Indeed, PVDF has the potential to support new technology generation of lexible electronic devices, but to preparere liable devices made with PVDF, such polymer needs to be sampled at high crystalline grade.;As PVDF is a semi-crystalline polymer its intrinsic lexibility represents a major advantage for lexible electronics which also increases manufacturing complexity of such material. To understand the crystalline behaviour of PVDF it is necessary to computationally investigate its fundamental physical properties per each of its crystal phase and the main behaviour of PVDF in conditions of inite temperature.;Density functional theory (DFT) calculations has been used as a quantum mechanical (QM) tool to solve the electronic structures of PVDF polymorphs obtaining structural information such as geometries, energetics, spontaneous polarisation and vibrational frequencies. Furthermore the impact of including van derWaals (vdW) forces in DFT was evaluated showing that the vdW-DF DFT functional had the best physical properties prediction agreement with experimental observations.;The vibrational frequencies of all PVDF polymorphs were computationally determined to verify the metastability of every crystal phase determined in the present study. Furthermore, the vibrational frequencies determination allowed to enrich the knowledge about adsorption peaks that each PVDF structure possesses to ease the computation to experimental IR spectra comparison.;The optimised geometries of PVDF crystals obtained from the DFT investigation have been scaled to molecular dynamics (MD) since it represents a time consistent methodology to follow the evolution of molecular interactions between particles. The interest was to compute the inite temperature dynamics, ensuring the use of the best performing force field and to gather new knowledge about the crystalline phase formation of PVDF liquid melts under different conditions such as bulk and confined between surface layers.;The effect of polymer confinement and surface/polymer electrostatics interaction were evaluated in such study showing that electrostatics played a main role in driving the formation of highly crystalline PVDF systems

From Community to Text and Back. On Semiotics and Ant as Text-Based Methods for Fleeting Objects of Study

This article illustrates a case study where the adoption of epistemological assumptions and data analysis techniques borrowed from both semiotics and ANT have enabled the researcher to transcend the limits that characterise traditional studies on online communities underpinned by a “sociology of the social” approach. Today, the very concept of “online community” seems to be at stake, to the point that it is no longer clear whether there exist online ties that are specific enough to be called “communitarian”. In order to analyse such an opaque and unstable object of study, innovative methods specifically developed to study fuzzy objects have to be devised and some epistemological questions have to be addressed. Approaches like semiotics and ANT turn out to be useful exactly because they use texts as “handles” to grasp heterogeneous, transient, objects of study. This article discusses in details a “funnel-like” method of analysis in a research field that has too often forgone the critique of epistemological assumptions inherited from other disciplines

Openness as an asset: A classification system for online communities based on actor-network theory

There exists a lack of consensus among scholars about the definition and categorization of technology-mediated communities. If these divergences hamper the possibility to devise a unique definition of online communities, some principia divisionis can nonetheless be found, in order to handle heterogeneity. Drawing upon case studies selected from Ars Electronica's Digital Communities competition, this paper analyses the limits of the categorization variables traditionally used to classify online communities, and proposes a new classification system made of two variables measuring the "openness" of the community. The first variable enacts Actor-Network Theory's distinction between mediators and intermediaries, while the second considers the degree of openness of the regimes of access and visibility enabled by groupware architectures. On-field evaluation of this classification system shows three advantages: since it is based on the abstract criterion "openness", it does not arbitrarily reduce the richness of the techno-social world, but rather allows researchers to cluster few types of online community. In addition, it is of some merit in tracking innovation in techno-social assemblages. \ua9 2010 ACM

Communities at a Crossroads. Material semiotics for online sociability in the fade of cyberculture

How to conceptualize online sociability in the 21st century? To answer this question, Communities at a Crossroads looks back at the mid-2000s. With the burst of the creative-entrepreneur alliance, the territorialization of the internet and the commercialization of interpersonal ties, that period constituted a turning point for digital communitarian cultures. Many of the techno-libertarian culture\u2019s utopias underpinning the ideas for online sociability faced systematic counter evidence. This change in paradigm has still consequences today. Avoiding both empty invocations of community and swift conclusions of doom, Annalisa Pelizza investigates the theories of actions that have underpinned the development of techno-social digital assemblages after the \u2018golden age\u2019 of online communities. Communities at a Crossroads draws upon the analysis of Ars Electronica\u2019s Digital Communities archive, which is the largest of its kind worldwide, and in doing so presents a multi-faceted picture of internet sociability between the two centuries. Privileging an anti-essentialist, performative approach over sociological understandings of online communities, Communities at a Crossroads proposes a radical epistemological turn. It argues that in order to conceptualize contemporary online sociability, we need first to abandon the techno-libertarian communalist rhetoric. Then, it is necessary to move beyond the foundational distinction between Gemeinschaft and Gesellschaft, and adopt a material semiotic approach. In the end, we might have to relinquish the effort to define online or digital communities and engage in more meaningful mapping exercises

Blame is in the Eye of the Beholder: Beyond an ethics of hubris and shame in the time of COVID-19

As misinformation and disinformation spread more rapidly and widely than ever before, individuals have been encouraged to be critical consumers of all received information. At the heart of this point of contention is the question of where responsibility and fault should lie. This framing and dynamic have taken a new form during the COVID-19 pandemic: a risk that the narrative of victim blaming may overcome narratives of care and responsibility, at all levels and across national contexts. This begs the question of which ethical assumptions individuals and institutions will build upon in navigating the crisis and developing policies and best practices for everyday life, as well as for what will come next

Neotropical Seasonally Dry Forests: Response of Soil Fungal Communities to Anthropogenic Actions

The aim of this review was to analyze the information available on soil fungal community of Neotropical Seasonally dry forests, with special attention given to the Chaco area. This review is focused on the loss of soil fungal community due to anthropogenic actions such as forest clearing. Over the last decades, the expansion of the agricultural frontier has had a wide range of physical, chemical and biological effects on Neotropical dry forests. As these changes on the Schinopsis dry forests (Chaco) have rendered the ecosystem vulnerable, these areas have become some of the few protected areas in South America. After analyzing both national and international studies to find the latest research available on the topic we have noticed there is lack of specific studies on soil fungal community in the Chaco area, unlike Cerrado and Caatinga where most studies have been carried out. Therefore, we propose to conduct more in-depth studies on soil fungi in Schinopsis forests to revalue the Chaco fungal community to use them as potential indicators of soil health and to develop new management techniques.Fil: Merlos, Cristina Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnolológico Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología. Laboratorio de Biología Funcional y Biotecnología; ArgentinaFil: Pelizza, Sebastian Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Moreno, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnolológico Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología. Laboratorio de Biología Funcional y Biotecnología; Argentin