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51.
How did traditional farming transform the natural environment in the Hawaiian Islands? This question is one that has largely been addressed for rainfed farming of crops like sweet potato (Ipomoea batatas), but evidence is lacking for irrigated farming of the critical staple crop taro (Colocasia esculenta). We describe the results of soil nutrient and sedimentological analyses of deeply-stratified pondfield deposits representing a 600-year-long record of irrigated taro farming in the North Kohala District, Hawai‘i Island. Soil is categorized by particle size to determine modes of transport and deposition, and concurrent soil nutrient analyses were conducted to infer shifts in the source of sediments and changes associated with taro harvesting. The advent of farming is clearly detectable in sedimentology, the presence of charcoal found within sediments, and soil chemistry. However, diminished nutrient concentrations can be attributed largely to deposition of a mixture of upstream sediments. Overall, there is no clear evidence for nutrient draw-down by taro harvesting, but we cannot yet rule it out as a factor. This study demonstrates the inherent difficulty of correlating changes in soil nutrients evident in irrigated pondfields with the long term history of soil nutrient cycling.  相似文献   
52.
In the island of Jaina, Campeche, red and yellow pigmented bones have been found. The study of the yellow and red colors in these burials is important for their possible interpretation, either religious, intentional coloring, or to understand taphonomic processes such as reactions of the original pigments with other compounds. Yellow color on bones is unusual in prehispanic burials.  相似文献   
53.
Martinelli, A.G., Bogan, S., Agnolin, F.L., Ribeiro, L.C.B., Cavellani, C.L., Ferraz, M.L.F. & Teixeira, V.P.A., iFirst article. First fossil record of amiid fishes (Halecomorphi, Amiiformes, Amiidae) from the Late Cretaceous of Uberaba, Minas Gerais State, Brazil. Alcheringa, 1–9. ISSN 0311-5518.

The first fossil amiid fishes (Halecomorphi, Amiiformes) from the Late Cretaceous Marília Formation (Bauru Group) at Uberaba County, Triângulo Mineiro region (Minas Gerais State, Brazil), are described. The material includes some partial maxillae, a dermopterotic, a cleithrum, several vertebral centra and teeth. Features such as the absence of a supramaxillary notch on the dorsal edge of the maxilla, a wide and deep pit on the maxilla for the articulation of the premaxilla, anterior portion of the maxilla with a sub-circular cross-section, teeth with acrodine cup with strong mesial and distal keels, among others, permit confident referral of the material to the Subfamily Vidalamiine (Amiidae), previously recognized in Lower Cretaceous strata of northeasthern Brazil. These specimens constitute the first Late Cretaceous record of this group in Brazil and one of the few in South America.

Agustín G. Martinelli [agustín_martinelli@yahoo.com.ar], Centro de Pesquisas Paleontológicas Llewellyn Ivor Price, Complexo Cultural e Científico Peirópolis (CCCP/UFTM), BR-262, Km 784, Bairro Peirópolis, Uberaba, Minas Gerais, Brazil; Sergio Bogan [sergiobogan@yahoo.com.ar], Fundación de Historia Natural ‘Félix de Azara’, Departamento de Ciencias Naturales y Antropología, CEBBAD—Universidad Maimónides, Hidalgo 775 piso 7 (1405BDB), Buenos Aires, Argentina. Federico Agnolín* [fedeagnolin@yahoo.com.ar], Sección Paleontología de Vertebrados, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, Av. Ángel Gallardo 470 (C1405BDB), Buenos Aires, Argentina. Luiz Carlos Borges Ribeiro [lcbrmg@terra.com.br], Camila Lourencini Cavellani [camila@patge.uftm.edu.br], Mara Lúcia da Fonseca Ferraz [mara@patge.uftm.edu.br] and Vicente de Paula Antunes Teixeira [vicente@patge.uftm.edu.br], Centro de Pesquisas Paleontológicas Llewellyn Ivor Price, Complexo Cultural e Científico Peirópolis (CCCP/UFTM), BR-262, Km 784, Bairro Peirópolis, Uberaba, Minas Gerais, Brazil. *Also affiliated with: Fundación de Historia Natural ‘Félix de Azara’, Departamento de Ciencias Naturales y Antropología, CEBBAD—Universidad Maimónides, Valentín Virasoro 732 (C1405BDB), Buenos Aires, Argentina. Received 15.4.2012; revised 11.6.2012; accepted 20.6.2012.  相似文献   
54.
The differences between boiled or unboiled bones are not often studied. However, they are crucial to understand postmortem rituals and to establish defleshing procedures and mortuary practices. In this work, human bones boiled in sea or fresh water are characterized. The bone composition, as well as the compounds present in the resulting materials, shows that salt alters the boiling process mechanism. Hence, from structural and morphological criteria, it is possible to distinguish if a bone has been boiled in salt or fresh water. In both sets of samples, the smoothness of the bone surface depends on boiling time, but only in bones boiled in seawater, filaments are observed apparently pouring out of the pores.Those differences which are mainly morphological (smoothness of the surface) are explained in terms of a collagen diffusional mechanism favored by sodium and chloride ions. For a boiling time of 6 h, the surface is covered by a thick layer or crusts of degraded collagen. Experiments with seawater may be used as model experiments to simulate taphonomical alterations in bones exposed to salt water.  相似文献   
55.
Performance-based earthquake engineering methodologies often require a probabilistic model of structural demand. Since observations masking the probability distribution of the majority of the data are frequently found, robust estimation methods are proposed to estimate the probabilistic model parameters (i.e., central value and dispersion). The performance of thirty-three robust dispersion estimators is evaluated, for different sample sizes, using the chord rotation, curvature, shear force, and inter-story drift demands obtained after analyzing five reinforced concrete structures under real earthquake records scaled to several intensities. Based on the results, combinations involving dispersion and central value (defined in a companion article) estimators are proposed.  相似文献   
56.
Over the course of the 1960s, Portugal, Rhodesia, and South Africa, hard-pressed by African nationalist movements and international opinion, grew closer together, realising that their common enemies could only be defeated by a common stance. The most important attempt to meet the threat to white political domination in Southern Africa was Exercise ALCORA, a military understanding negotiated, in secret, in October 1970. From then until the Portuguese Revolution in 1974, regular meetings of the representatives of the three countries’ armed forces pooled intelligence and defined new strategies for the on-going conflicts in Rhodesia, Angola, and Mozambique, and put in train plans for future, larger-scale clashes. This article examines the origins of ALCORA, charting the process by which Lisbon, Salisbury, and Pretoria came together despite considerable obstacles. It highlights the importance of domestic factors, notably in South Africa, ALCORA's senior partner. There, the murder in 1966 of Prime Minister Hendrik Verwoerd led to a circumstance wherein leading figures of the regime enjoyed much greater freedom in the definition of policy than before. One beneficiary was Defence Minister P. W. Botha who, with the army's backing, would develop a total strategy against what was perceived as a total threat. Exercise ALCORA was a key component of this strategy.  相似文献   
57.
Abstract. This article analyses the discussion, enactment and characteristics of the Linguistic Policy Act adopted by the Catalan Parliament in 1998, from the point of view of current normative political theory. The main theoretical question is whether its provisions promoting the Catalan language are compatible with the liberal political tradition, considering its different streams. The discussion shows that the main arguments are not different from those used by scholars dealing with issues of national and cultural pluralism in Western democratic societies. Thus, the opponents of the Act tend to rely upon various individual rights‐based arguments taken from classical liberalism. Its advocates, on the other hand, accuse them of neglecting the value of cultural membership, asserted by influential authors within the liberal tradition. Ultimately, the article concludes that this law neither promotes nor allows illiberal practices.  相似文献   
58.
The colluvial soils of Galicia (NW Spain) are records of Holocene environmental change. In spite of the omnipresence of charcoal fragments in these soils, the effect of fires on the development of the Galician landscape and the potential role of past societies are poorly understood.  相似文献   
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60.
ABSTRACT

Earthquakes have been responsible for the destruction of hundreds of monuments throughout human history. Due to their size, conservation state, and lack of seismic provisions, monuments are particularly vulnerable to the effects of geological hazards. The first step toward the mitigation of the earthquake threat consists of understanding the existing seismic risk and evaluating possible strategies to reduce it. This study presents a simplified assessment to evaluate the probability of damage due to ground shaking on UNESCO World Heritage cultural sites throughout Europe. The seismic hazard model (SHARE) has been employed to derive hazard curves, which were combined with a fragility model to calculate the annual probability of damage or collapse. These calculations were performed assuming different soil conditions, and the resulting risk metrics can be used for risk awareness, to inform the prioritization of the sites in need of structural interventions, and to support additional risk analysis.  相似文献   
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