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971.
This paper presents a detailed elemental analysis of 64 glass beads and pendants dated to the Meroitic period (first–third centuries ad ) and the Nobadian period (fourth–sixth centuries) from burial sites in the Lower Nubian Nile Valley region. Laser ablation‐inductively coupled plasma‐mass spectrometry (LA‐ICP‐MS) was used to determine the chemical composition of the glass and to gain knowledge about its origin. Four main glass types were identified: low‐alumina soda‐lime glass, high‐alumina glass, plant‐ash soda‐lime glass, and mixed‐alkali glass. Mineral soda‐lime glass (m‐Na‐Ca) of East Mediterranean/Egyptian provenance is dominant within the low‐alumina glass group from Meroitic and Nobadian periods. Mineral soda high‐alumina glass (m‐Na‐Al) appeared in the Nobadian bead assemblages, and the m‐Na‐Al 1 subtype was produced in Sri Lanka/South India. An initial insight into the origin of the glass beads in Nubia from the first to sixth centuries is described, indicating the first evidence for the presence of Asian objects in Nubia. The data obtained for the bead trade in North‐east Africa in this study has allowed a new light to be shed on the westward flow of Asian glass during a time of intensive maritime trade contacts with the wider Indian Ocean world.  相似文献   
972.
Tree‐ring dating involves matching sequences of ring widths from undated timbers to dated sequences known as ‘master’ chronologies. Conventionally, the undated timbers (from a building or woodland) are sequentially matched against one another, using t‐tests to identify the relative offsets with the ‘best’ match, thus producing a ’site’ chronology. A date estimate is obtained when this is matched to a local master chronology of known calendar age. Many tree‐ring sequences in the UK produce rather low t‐values and are thus declared not to have a ‘best’ match to a master chronology. Motivated by this and the routine use of Bayesian statistical methods to provide a probabilistic approach to radiocarbon dating, this paper investigates the practicality of Bayesian dendrochronology. We explore a previously published model for the relationship between ring widths and the underlying climatic signal, implementing it within the Bayesian framework via a simulation‐based approach. Probabilities for a match at each offset are produced, removing the need to identify a single ‘best’ match. The Bayesian model proves successful at matching in both simulated and real examples.  相似文献   
973.
The following study sheds new light on the quality control procedures of ancient potters by comparing cooking vessels exported from the medieval kiln‐site of Cabrera d'Anoia (Barcelona) with ‘wasters' that were discarded at source. The firing temperature of examined sherds indicates that only pots subjected to a maximum temperature of 800–850°C were offered for sale. The potters at Cabrera d'Anoia appear to have been fully aware of the optimal balance between thermal and physical shock resistance of vessels fired within this range and strived to control firing in order to achieve better products than that of competing workshops.  相似文献   
974.
975.
Under the right conditions, compounding socio‐political and economic change can dramatically alter government policy. From 2000, Western Australia, a resource‐rich jurisdiction, experienced significant change owing to a once‐in‐a‐generation resources boom, which forced a break with earlier development approaches. In 2008, regional interventionism returned to the State via the State Government's Royalties for Regions program. Departing from the neo‐liberal tradition, the program allocated 25 per cent of the State's royalty income to non‐metropolitan regions, over and above existing regional allocations, and its success remains disputed. While it is easy to question the program retrospectively, the socio‐economic and political circumstances from 2000 to 2008 reveal a “perfect storm” of conditions enabling the transition from neo‐liberalism to interventionism in regional development. This paper sets out to understand the multi‐faceted conditions that enabled the dramatic paradigm shift embodied by the program. To this end, it examines the State's rural–urban settlement dichotomy, its staples economy, and the policy context leading up to the program. Following that, the paper proposes a causal framework mapping out the factors driving and rationalising the program. These factors are then examined in detail and include perceived rural voter disenchantment, ineffectual regional development policy, the State's mining boom, inadequate regional development funding, the contrasting fortunes of two regions (illustrative of the impact of growth, and the lack thereof), and the political manoeuvring during the 2008 election. Finally, the paper concludes by considering how the conversion of these conditions resulted in the State's most significant regional policy redirection in decades.  相似文献   
976.
Inference regarding the impact of urban areas on health is limited by cross‐sectional studies assessing few dimensions and ignoring area‐level socio‐economic status. This study simultaneously assessed several dimensions of the built environment against incident cardiometabolic risk (CMR) arising over 10 years. It tested the hypothesis that, accounting for local area relative wealth, features of the built environment would not predict incident CMR. Initially, disease‐free adults in a biomedical cohort in Adelaide, Australia, provided address and clinical data over three waves of follow‐up. CMR was defined as the count of five clinical CMR factors. Built environment measures were derived for urban form, and natural, and food environments. Local area wealth was expressed using the relative location factor index. Poisson growth models accounting for within‐suburb clustering, age, sex, and education were used to estimate associations between built environment measures and increasing CMR. Fitted linear trajectories had statistically significant mean values of intercepts and slopes. CMR trajectories were associated with age, male sex, and low education. In models including measures of the food, natural, and urban form environments, per standard deviation increase, only POS count predicted incident CMR, which was more strongly predicted by relative location factor. Not accounting for local area socio‐economic status may overestimate the strength of relationships between health and the built environment. Inequity in accessible POS is robustly related to incident CMR.  相似文献   
977.
Ripley's K‐function is a test to detect geographically distributed patterns occurring across spatial scales. Initially, it assumed infinitely continuous planar space, but in reality, any geographic distribution occurs in a bounded region. Hence, the edge problem must be solved in the application of Ripley's K‐function. Traditionally, three basic edge correction methods were designed for regular study plots because of simplified geometric computation: the Ripley circumference, buffer zone, and toroidal methods. For an irregular‐shaped study region, a geographic information system (GIS) is needed to support geometric calculation of complex shapes. The Ripley circumference method was originally implemented by Haase and has been modified into a Python program in a GIS environment via Monte Carlo simulation (hereafter, the Ripley–Haase and Ripley–GIS methods). The results show that in terms of the statistical powers of clustering detection for irregular boundaries, the Ripley–GIS method is the most stable, followed by the buffer zone, toroidal, and Ripley–Haase methods. After edge effects of irregular boundaries have been eliminated, Ripley's K‐function is used to estimate the degree of spatial clustering of cities in a given territory, and in this paper, we demonstrate that by reference to the relationship between urban spatial structure and economic growth in China.  相似文献   
978.
979.
Archaeological survey by the Qatar National Historic Environment Record Project (QNHER) in 2009, led to the discovery of a Neolithic flint scatter, a settlement and an ancient, raised shoreline associated with higher, mid‐Holocene sea levels at Wādī ?ebay?ān, north‐western Qatar (Al‐Naimi et al. 2010, 2011; Cuttler, Tetlow & Al‐Naimi 2011). The QNHER project is a collaboration between Qatar Museums and the University of Birmingham, which over the past five years has developed a national geospatial database for the recording of archaeological sites and historic monuments in Qatar. A significant aspect of the project involved archaeological survey and excavation in advance of major construction projects. Between 2012 and 2014 excavations at Wādī ?ebay?ān revealed a burial of a typology previously unknown in Qatar, the unmarked graves (Cuttler, Al‐Naimi & Tetlow 2013).  相似文献   
980.
Human skeletons were recovered in two unmarked burials blown to the surface of a dune south‐west of Jebel al‐Emeilah in the Central Region of the Sharjah Emirate (UAE). Sasanian stamp seals were found associated with one of the individuals. A bone fragment of this individual provided a direct radiocarbon date placing it in the Middle Sasanian period. With the aid of strontium isotope analysis it was possible to determine that the two individuals were immigrants to the area that is now part of the UAE.  相似文献   
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