An integrated diagnostic approach for the assessment of historic masonry structures

Knowledge of the structural behaviour of existing masonry requires a multi-level approach, with the proper application of diagnostic and assessment methodologies. The structural performance of masonry wall structures can be understood provided that the history of their construction, their geometry, the characteristics of their masonry texture, and the characteristics of the masonry as a composite material are known. In order to obtain all these data, an effective on-site testing program, which can involve the application of different test methodologies as a combination of destructive tests (DT), minor destructive tests (MDT) and non-destructive tests (NDT), needs to be performed. Furthermore, the effectiveness of applied methodologies for the assessment of historical masonry structures strongly depends on the type of investigated structure, as well as on the appropriate numerical model for the analysis. However, the unclear aspects of any testing programme remain the same – how efficient is a particular testing technique, and how can it be assessed? Following the results of recently carried out EU and national research projects, a comprehensive set of data regarding the effectiveness of different testing methods, depending on the type of problem, have been collected and analyzed. Within this framework, several masonry heritage structures from Slovenia, which differ both from the historical and structural point of view (Pi?ece Castle, the Carthusian Monastery at ?i?e, and a typical stone-masonry house from the So?a Valley region), have been investigated by means of different techniques, and numerically analyzed. For this purpose, two different models were used: a push-over model based, on the structural element method, and FEM analysis. It was concluded that the effectiveness of any particular diagnostic technique for the investigation of masonry structures, and for the planning of their restoration, depends on numerous factors. An attempt to determine which of the techniques could be appropriate, depending on the problem, was made. No single test is self-sufficient for the solving of a particular problem, so a combination of different NDT, MDT and DT should be performed. Summarizing all the results, it can be said that, in the process of assessing the state of a structure, even a simple investigation technique is better than none. The effort will always be repaid - if not already in the planning stage of the restoration and retrofitting actions, then certainly in the execution stage of the revitalization works, on site.     

Wall base ventilation system to treat rising damp: The influence of the size of the channels

One of the major causes of pathologies in our historic buildings is the presence of moisture, particularly rising damp. Since these constructions tended to be built near water lines, to facilitate their supply, and because their walls are mainly made of high porosity materials, the presence of rising damp is constant. Although many historic buildings in Portugal have already been the targets of interventions to eliminate pathologies, the fact is that it has not been possible to do it properly. The treatment techniques available nowadays are quite diverse but all of them have low applicability to historic constructions. Research has been carried out, in this past years, at the Department of Civil Engineering of the University of Coimbra in collaboration with Department of Civil Engineering of the Faculty of Engineering of the University of Porto to try and solve this problem. An old but poorly studied technique has been investigated experimentally and numerically in the past few years: ventilation of the base of the walls. It was experimentally validated to limestone walls 20 cm thick. Numerical investigation has been carried out in order to analyze the influence of different parameters on its efficiency. In this paper we present the results of the latest investigations that have been carried out about the influence of the size of the ventilation channel on its efficiency.     

Growth,accessibility and the distribution of arts activity in the United States: 1980 to 1990

Using data on the location of artists by state as a proxy for the location of artistic activity, this paper shows that from 1980 to 1990 the arts grew rapidly and became more dispersed, reversing a trend toward greater concentration during the 1970s. Accessibility increased as the ratio of artists to population rose in most states. Nevertheless, enormous inter-state variation in that ratio remains. The second part of the paper examines the determinants of artist location at the state level. The equations estimated for both years prove to have a high degree of explanatory power.This paper was presented at the 9th international conference of the Association for Cultural Economics, held in Boston, May 8–11, 1996.     

Consolidating properties of Regalrez 1126 and Paraloid B72 applied to wood

This study is aimed at an assessment of the properties of two polymeric products applied to Norway spruce (Picea abies) and White poplar (Populus alba) wood species. It contributes to ongoing research experiments on the consolidating properties of two synthetic resins and their potential synergic action on wood, resulting from their different interaction with the substrate: Paraloid B72 and Regalrez 1126. Experiments were carried out on a series of samples of the two wood varieties. The consolidants were applied alone and one after the other, with one coat of Regalrez and then one of Paraloid. Porosity and variations in pore size distribution were ascertained by mercury intrusion porosimetry (MIP). Colorimetric and IR spectroscopic measurements were also taken before and after aging by solar radiation and freeze/thaw cycles, to verify the possible slowing of photodegradation of the treated wood and the consolidating resistance. Results confirm that both products penetrate the wood with a different behaviour. After double treatment with Regalrez + Paraloid, a significant advantage was observed in terms of mechanical resistance and pore size distribution, although no advantages as regards resistance to photo-oxidizing processes or colour changes were observed.     

A study of mechanical properties of papers exposed to various methods of accelerated ageing. Part I. The effect of heat and humidity on original wood-pulp papers

The damage to historical documents and books caused by the acidic character of paper is often manifested as a complete loss of their mechanical properties. Deacidification and restoration of archived paper objects require knowledge of the long-term behaviour of paper before and after repair actions. Our study was focused on the investigation of mechanical properties (tensile strength, stretch, tensile index, zero-span tensile strength, folding endurance) of original papers (one alkaline and three different acidic samples) exposed to five methods of dry-heat and moist-heat accelerated ageing. The degree of paper deterioration upon ageing was significantly influenced by the temperature and relative humidity, along with the intrinsic chemistry of the individual paper samples. The correlation matrix evaluated at a 95% confidence level for tensile strength, stretch, tensile index and zero-span showed linear correlations between these mechanical properties for all the paper samples. However, a linear dependence of folding endurance on zero-span tensile strength was found only for alkaline paper, which revealed the highest resistance to the accelerated ageing tests. In addition, the concentration of paramagnetic semiquinone species in the acidic lignin-containing paper samples was monitored by Electron paramagnetic resonance spectroscopy.     

张洁:告别乌托邦的话语世界

20世纪80年代中期以来,张洁彻底告别了热情高歌式的理想主义文本模式,以亵渎"崇高"、调侃"神圣"的叙述立场,"挑战假相"的叙述姿态,反讽与讽刺相结合的叙述策略,片断拼接式的叙述结构,解构与颠覆了其前期作品以热诚的信仰、纯真的情感、和谐均衡的叙述方式、温婉感伤的语言格调为特点的乌托邦话语定势.     

From Regulatory Knowledge to Regulatory Decisions: The European Evaluation of Medicines

Medicines regulators have generally adopted a scientistic view of medicines evaluation, which they present as an exercise that should—and indeed can—be purely “objective,” based only on knowledge produced through validated research protocols. The growing body of social science literature analyzing the regulation of medicines has questioned this pretense of objectivity and underlined the socio-political construction of evidence on the risks and benefits of medicines. But while the European Medicines Agency has become the dominant regulatory body in Europe and a key player at world level, very few studies have investigated its actual practices. Based on interviews with European regulators, but also on direct observations of several meetings of the European Medicines Agency’s main expert committee, this article aims to analyze how regulatory knowledge is defined and then transformed into regulatory decisions. First, it describes the main characteristics of European medicines regulation and the historical definition of what can count as “objective” evidence on the safety and efficacy of medicines. Second, it demonstrates that experts use many different types of knowledge in building their opinions: the results of studies, but also knowledge about firms’ past and present strategies, about patients’ needs and future behavior, about the state of research and clinical practices, and about legal and policy-making issues. Third, it explains why, in spite of the various forms of knowledge involved, experts manage to produce consensual opinions on medicines and why these opinions are considered genuine decisions in the sector.     

The value of a good reputation online: an application to art auctions

Using a unique dataset of art auctions on eBay, we conduct an empirical analysis of the value of a seller’s online reputation. Several aspects distinguish our work from most existing research. We analyze a heterogeneous panel data consisting of a large number of observations over a large period of time, including significant variation in reputation across and within sellers. The panel structure of our dataset allows us to employ fixed effects techniques to control for observed and unobserved differences across auctions. Our results point to a highly significant, and sizable, impact of a negative reputation on the behavior of market participants and on market outcomes. Negative feedback is associated with a significant reduction in the number of bidders and a reduction in the probability of sale; negative feedback is also associated with a significant reduction in sale price. Consistent with previous research, the impact of additional positive feedback on market outcomes for the seasoned sellers in our sample is not statistically significant.     

From Green Revolution to Green Evolution: A Critique of the Political Myth of Averted Famine

This paper critiques the so-called “Green Revolution” as a political myth of averted famine. A “political myth,” among other functions, reflects a narrative structure that characterizes understandings of causality between policy action and outcome. As such, the details of a particular political myth elevate certain policy options (and families of policy options) over others. One important narrative strand of the political myths of the Green Revolution is a story of averted famine: in the 1950s and 1960s, scientists predicted a global crisis to emerge in the 1970s and beyond, created by a rapidly growing global population that would cause global famine as food supplies would not keep up with demand. The narrative posits that an intense period of technological innovation in agricultural productivity led to increasing crop yields which led to more food being produced, and the predicted crisis thus being averted. The fact that the world did not experience a global famine in the 1970s is cited as evidence in support of the narrative. Political myths need not necessarily be supported by evidence, but to the extent that they shape understandings of cause and effect in policymaking, political myths which are not grounded in evidence risk misleading policymakers and the public. We argue a political myth of the Green Revolution focused on averted famine is not well grounded in evidence and thus has potential to mislead to the extent it guides thinking and action related to technological innovation. We recommend an alternative narrative: The Green Evolution, in which sustainable improvements in agricultural productivity did not necessarily avert a global famine, but nonetheless profoundly shaped the modern world. More broadly, we argue that one of the key functions of the practice of technology assessment is to critique and to help create the political myths that preserve an evidence-grounded basis for connecting the cause and effect of policy action and practical outcomes.

     

Consolidation of stone blocks prior to placement: A case study of the Roman wall in Tarragona (Spain): Report and methodology

The possible pre-consolidation of the stones used to repair the Roman wall of Tarragona was studied, on the premise that this had been carried out prior to placement in the wall. A detailed study of the stones was conducted in order to determine whether they had been treated, and if so, how this had been done. A semi-quantitative X-ray mineralogical analysis using the Rietveld method was performed, together with porosity and textural analyses. This paper concludes with a discussion of how the stones studied here were pre-consolidated using lime slurry.     

From biblical exegesis to crises of european modernity: Reflections on girardian theory and its limitations

Over the last two decades the field of ‘Girard studies’ – the application of René Girard's theories on mimetic desire and sacrificial violence to cultural artifacts – has tended to focus increasingly on Biblical texts and theological implications of Girard's interpretation of Christianity as a ‘theory of man.’ After summarizing Girardian theory in its current form, this essay stresses the applicability of the theory to François Furet's reading of the crisis of bourgeois culture and to Pascal Bruckner's reading of the malaise of the post Cold War world and the ethnic crises associated with the break‐up of the former Yugoslavia. This essay also demonstrates how Girardian theory illuminates the recent historical and judicial crises associated with France's efforts to come to terms with the memory and legacy of the collaborationist Vichy regime during World War II. The essay concludes with a brief assessment of the advantages as well as the pitfalls of employing Girardian theory to demystify the crises of modernity.     

The Construction of Brownness: Latino/a and South Asian Bloggers' Responses to SB 1070

The vernacular discourses of Latino/a and South Asian American bloggers in the context of SB 1070, legislation recently passed in Arizona, illustrate how their shared experiences of discrimination (re-)articulate “brownness” as a complex racial formation aligned with constructions of “illegal” immigrants. Bloggers' differentiation of their subjective experiences of alien citizenship and racialized belonging from white or black citizenship problematizes the rigidity of their “middling” positionality within the U.S. racial structure, encouraging a more contextualized approach. I consider the bloggers' varied constructions of brownness, its distinctive positionality within racial structures, and their contestations of the discourses that racialize brown identities.