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61.
    
Aspects of 2nd- to 5th-century ce Roman production technology and knowledge transfer in southern Austria (known as Noricum) were examined. With no evidence for workshops identified in the study area, 44 grey ware bowls from two sites at Aguntum and Lavant were studied macroscopically, and combined with optical microscopy, X-ray powder diffraction, prompt gamma activation, neutron activation and scanning electron microscopy, in order to understand whether one (large) workshop supplied these bowls, or whether the bowls were produced by several (small) workshops nearby. Combined with information from the geological background, the results were used to tentatively indicate the production location. The results indicate that the grey ware bowls from Aguntum and Lavant were produced by local workshops nearby. The bowls were manufactured with similar clay sources, tempered with crushed calcite-marble rocks from the Tauern Window, their surface smoothed and burnished, and fired between 800 and 850°C in a reducing atmosphere of an open fire. This is taken to suggest that Roman potters, who were located at Aguntum and Lavant, shared strategies of raw materials selection, paste preparation, finishing and firing, and transferred technological knowledge through time.  相似文献   
62.
This contribution to the Forum Debate responds to Horner and Hulme's analysis on the ‘rise of the South’, which they see as suggesting a dramatic redrawing of the global map of development and inequality. This response presents a critical South feminist perspective, informed by the lived realities of women in the South. It is based on a historical and political perspective that goes beyond income inequality to understand gender inequality in development within the persistent North–South divide.  相似文献   
63.
Neutron activation analysis (NAA) of ceramics from Xaltocan (n?=?651) displays high values for sodium and potassium and low concentrations of many transition metals and rare earth elements compared to other sites in the Basin of Mexico. Given that Xaltocan was situated on an island in the middle of a saline lake, the potential reasons for this chemical signature are diverse. On one hand, if the sodium and potassium were elevated due to some behavioral aspect of the potters, the Xaltocan chemical groups provide a glimpse at the behaviors of Xaltocan potters that permit more precise source designations. On the other hand, if this chemical fingerprint arose due to contamination in a saline post-depositional environment, the Xaltocan chemical groups would not be valid references for provenance studies. To evaluate these alternative hypotheses, we employ several lines of evidence: (1) comparison of the Xaltocan ceramics to over 5,000 NAA assays of clays and ceramics from the Basin of Mexico, (2) experimental doping of clays with water of different salinities and fired to different temperatures, (3) leaching experiments of archaeological pottery sherds (n?=?22) recovered from the site of Xaltocan, and (4) laser ablation–inductively coupled plasma–mass spectrometry of the clay and temper fraction of a small sample of Xaltocan ceramics to determine which component is responsible for the elevated sodium and potassium values. The results suggest that the high sodium and potassium values were present in the ceramic paste before firing. We then use these newly established reference groups to better understand the role of Xaltocan in the regional economy. The type of experimentation employed in this study has proven to be an important method for determining the behaviors of ancient potters and distinguishing them from post-depositional processes.  相似文献   
64.
This study presents bone collagen carbon and nitrogen isotope data from the Migration Period cemeteries (fifth/sixth century AD) of Obermöllern and Rathewitz in Central Germany. The human average δ 13C ratios of ?19.8?±?0.3 ‰ and δ 15N ratios of 9.6?±?0.9 ‰ (n?=?43) reflect a mixed diet in a temperate C3-based ecosystem without significant difference between the two sites. The average offset between human and faunal δ 13C and δ 15N values indicates a significant contribution of plant food to the human diet that has different isotope ratios from the forage of the animals. It furthermore suggests the influence of land management on the δ 15N values. One adult male from Obermöllern stands out due to his elevated nitrogen isotope ratio, body height, grave goods, and burial position. The collagen isotope data of this study are comparable with data from other central European sites and confirm rather stable communities with moderate variation in the environmental conditions of arable land.  相似文献   
65.
This study describes a thorough inspection of a 20th century church in the town of Isla Cristina (in the province of Huelva, southwestern Spain), which is currently awaiting restoration. The study indicates the damage processes at work in the building structure materials (brick, concrete, steel, and wood), which are closely related to its geographical location, and analyses the deterioration of the wooden roof structure. The analysis of the wooden roof includes the results of an inspection methodology on a protected building based on traditional techniques such as visual inspection and innovative non-destructive inspection techniques (visual classification, ultrasounds and thermography). Fieldwork consisted of the visual classification of the wooden pieces according to Spanish standard UNE 56544:2007 specifications after which ultrasound and thermography techniques were applied on-site. A second stage involved laboratory tests (anatomic identification, density and bending strength) using wood samples extracted from the structure in order to check the values for the physical and mechanical properties previously recorded by non-destructive techniques (NDT). These non-destructive techniques are used in inspections of the wooden roofs of buildings to identify dampness, deterioration, density loss and defects as a means of assessing their conservation status. This work concludes that the use of ultrasound and thermography techniques constitute an accurate diagnostic tool for the on-site inspection of wooden structures and the evaluation of their condition. Thermography identifies different materials and moisture content while ultrasound detects the various degrees of deterioration and density-loss in areas of the wood with high moisture content.  相似文献   
66.
Cross-Border M&As and the Changing Economic Geography of Europe   总被引:4,自引:0,他引:4  
This study investigates the patterns of corporate mergers and acquisitions (M&As) involving firms located in the EU25 as well as in the four EFTA countries between 1998 and 2003. Against the background of a reflection on the concept of the firm in economic geography, it uncovers the cross-border balance of M&As across European states and identifies the factors that may explain the levels and patterns of corporate takeovers across Europe. The results indicate that the traditional motives of access to new and core markets, the effects of geographical proximity, and the internalisation of localised capabilities (proxied by a skilled and innovative labour pool) represent the key drivers of European M&As, while institutional factors, such as European integration or language barriers, appear to be less influential.  相似文献   
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68.
    
This article seeks to explain the conditions for the emergence and institutionalization of the cultural paradiplomacy of the city of Barcelona and its local effects. The recognition of the city as an active participant on the international stage is based on its evolution from an industrial to a service economy. Against this backdrop, Barcelona’s city council, in common with many other city authorities operating in the world’s metropolises during the 1980s, initiated its own cultural paradiplomacy as a strategy for attracting capital and promoting local development. This policy became established as part of a new multilevel system of governance. This article analyzes the causes of the institutionalization of this activity from an intergovernmental perspective. It concludes that in the context of economic globalization, the emergence of cities’ cultural paradiplomacy is strongly related to the restructuring of the State and its external administration and to the intensification of the ‘cultural branding’ of cities as a tool for global competition.  相似文献   
69.
    
This essay analyzes the history of the Nerve Growth Factor (NGF) discovery, relating some of the principles of the theory of scientific creativity to the cognitive and personal qualities of the scientists that participated in the discovery, particulary Rita Levi-Montalcini and Viktor Hamburger. The discovery of NGF is especially attractive for the history of science as it involves chance, luck, creativity, and some extraordinary scientists.  相似文献   
70.
At La Espiral cave, located in Bahia Honda municipality (Artemisa province, Cuba), there are several pictographs, including two of particular importance due to the design used: one of concentric circles and another of a spiral. We analyzed the pigments and binders used in one of these pictographs. The chemical ingredients of the paint are considered in this article, as well as the use of bat guano as a major pigment compound. The apparent presence of ellagic acid, ellagitannin, or anthocyanins would strengthen the hypothesis that artists used vegetable protein as a paint binder or solvent.  相似文献   
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