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11.
In Turkey, with the occurrence of almost every strong and even moderate earthquake, damage to masonry minarets is observed. In the present work, efficiency of vertical post-tensioning application to reinforce masonry minarets against earthquakes has been investigated. Considering a representative minaret and its post-tensioned counterpart, and performing spectral and time-history analyses, the effects of post-tensioning on the axial stresses, top lateral displacements and overturning safety have been determined. Obtained results have shown that vertical post-tensioning application is a very efficient method to reduce axial tensile stresses and lateral displacements, and to assure the overturning safety of masonry minarets against earthquakes.  相似文献   
12.
In this paper, we look at what it means to ‘eat Hawai'i’ and examine how Hawai'i Regional Cuisine (HRC) imagines, produces, and consumes place through particular constructions of local foods. The term ‘local’ attaches to foods as a marker of numerous positive attributes such as seasonal, sustainable, and community-based. Drawing upon ongoing ethnographic research on Hawai'i Island, we examine spatial and discursive constructions of local and how this particular cuisine places itself in local food networks while simultaneously using place to localize itself within the Island's food networks. Using a case study approach to carefully contextualize localness, we show how Merriman's Restaurant and HRC complicate notions of alternative and local food systems in its discursive and material production and reproduction of Local food and locally grown food.  相似文献   
13.
Buckley et al. (2010) recently identified a Type I collagen (COL1A2) peptide sequence that discriminates between sheep and goat species. The exact location of this peptide sequence on the genome was not reported. We identified the sequence's location and developed a PCR based approach that amplifies the diagnostic sequence from exon 41 of the COL1A2 gene. Using DNA analysis, we confirmed that this COL1A2 peptide discriminates between goat and sheep species reliably, but is limited as a more general phylogenetic marker.  相似文献   
14.
We have determined the composition of rock art pigments from two megalithic barrows located in the north of Portugal. The use of XRD, SEM–EDS and FT–IR spectroscopy confirmed the presence of hematite and kaolinite in the red pigments from the Eireira barrow, and kaolinite in the white pigment from the Leira das Mamas barrow. The organic composition of the pigments was studied by GC–MS, suggesting that the red sinuous lines and dots from the Eireira barrow were prepared with cooked or heated algae and/or aquatic plants, with egg as binder, while the white pigment from the Leira das Mamas barrow revealed a mixture of vegetable oils for kaolinite moulding, which could be stabilized by temporary exposure to high temperatures. The multi‐analytical approach used on this study of megalithic pigments allowed the recovery of important data about north‐western prehistoric communities, namely the way in which they exploited existing resources and their ability to transform them.  相似文献   
15.
This article overviews the research opportunities made possible by a National Institute on Aging-funded program project, Early Indicators, Intergenerational Processes, and Aging. Data collection began almost three decades ago on 40,000 soldiers from the Union Army in the U.S. Civil War. The sample contains extensive demographic, economic, and medical data from childhood to death. In recent years, a large sample of African-American soldiers and an oversampling of soldiers from major U.S. cities have been added. Hundreds of historical maps containing public health data have been geocoded to place soldiers and their family members in a geospatial context. With newly granted funding, thousands of veterans will be linked to the demographic information available from the census and vital records of their children.  相似文献   
16.
Although the issue of the out-of-plane response of unreinforced masonry structures under earthquake excitation is well known with consensus among the research community, this issue is simultaneously one of the more complex and most neglected areas on the seismic assessment of existing buildings. Nonetheless, its characterization should be found on the solid knowledge of the phenomenon and on the complete understanding of methodologies currently used to describe it. Based on this assumption, this article presents a general framework on the issue of the out-of-plane performance of unreinforced masonry structures, beginning with a brief introduction to the topic, followed by a compact state of art in which the principal methodologies proposed to assess the out-of-plane behavior of unreinforced masonry structures are presented. Different analytical approaches are presented, namely force and displacement-based, complemented with the presentation of existing numerical tools for the purpose presented above. Moreover, the most relevant experimental campaigns carried out in order to reproduce the phenomenon are reviewed and briefly discussed.  相似文献   
17.
Summary.  Despite the marginality of the region, the Later Bronze Age and Iron Age communities of the north-west of the Iberian Peninsula were engaged in active relationships with both Atlantic and Mediterranean peoples. Unlike other Atlantic regions, the area maintained direct contacts both with Mediterranean sailors and with the communities of the British Isles and north-western France simultaneously. The social relevance of these interactions and the range of imported goods transported varied throughout the first millennium BC. New evidence shows an intense involvement in Mediterranean trade from the fifth century BC onwards, while Atlantic contacts increased from the late second century BC, to reach a climax under Roman rule (first–second centuries AD).  相似文献   
18.
The Awá are a group of hunter-gatherers in transition to agriculture living in the Brazilian Amazon forest. After contact with mainstream society from the 1970s onwards, their culture, and especially their material culture, has undergone important transformations. Many traditional technologies and artifacts have been lost, especially those related to women. In this context, the persistence of arrow-making, although threatened by the spread of shotguns, is remarkable. During ethnoarchaeological work conducted between 2005 and 2009, we have been able to observe that the everyday making and use of arrows cannot be explained in neither functional nor symbolic terms alone. From our observations, we conclude that making and using arrows is indissolubly woven with the self of Awá men and, for that reason, we consider that only a relational-ontological approach can help us understand the deep relationship between men and arrows. Finally, we argue that the Awá case offers new possibilities to investigate technologies of the self in other non-modern societies.  相似文献   
19.
ABSTRACT

Earthquakes cause severe damage to masonry structures due to inertial forces acting in the normal direction to the plane of the walls. The out-of-plane behavior of masonry walls is complex and depends on several parameters, such as material and geometric properties of walls, connections between structural elements, the characteristics of the input motions, among others. Different analytical methods and advanced numerical modeling are usually used for evaluating the out-of-plane behavior of masonry structures. Furthermore, different types of structural analysis can be adopted for this complex behavior, such as limit analysis, pushover, or nonlinear dynamic analysis.

Aiming to evaluate the capabilities of different approaches to similar problems, blind predictions were made using different approaches. For this purpose, two idealized structures were tested on a shaking table and several experts on masonry structures were invited to present blind predictions on the response of the structures, aiming at evaluating the available tools for the out-of-plane assessment of masonry structures. This article presents the results of the blind test predictions and the comparison with the experimental results, namely in terms of formed collapsed mechanisms and control outputs (PGA or maximum displacements), taking into account the selected tools to perform the analysis.  相似文献   
20.
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