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111.
We review evidence from human biology—paleopathological and isotopic paleodietary studies on ancient Maya skeletons—to assess the validity of ecological models of the Classic Maya collapse, in which elevated disease and deteriorating diet are commonly assumed. To be upheld, the health arguments of ecological models require that the Maya disease burden (1) was greater than that for many other societies and (2) increased over the span of occupation. The dietary argument requires (1) consistent change in diet from Preclassic and Early Classic Periods to the Terminal Classic and (2) increasing social divergence in diet. A correlation between diet and disease is necessary to link these arguments. Neither pathology nor isotopic data consistently support these criteria. Instead, it appears that local environmental and political factors created diversity in both disease burden and diet. In view of the human biological data, we are skeptical of ecological models as generalized explanations for the abandonment of Classic Maya sites in the southern lowlands.  相似文献   
112.
Multiple sclerosis (MS) was first presented in a clinical setting in 1838. In this paper the presentation and treatment of a transient hemiparesis in a drummer in 1789 is discussed. This may have been an early case of MS and presents evidence against the theory that MS is an infectious disease beginning in the 19th century.  相似文献   
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This paper considers the impact of technology on methods used to classify land potential. With developments in new technologies such as Expert Systems (ES) and Geographic Information Systems (GIS), McKeown (1987) proposes a new method by which to explain the decision making process for land classification to an end user. Consideration is given to McKeowns' concept and the literature reviewing both traditional land classification methods and ES and GIS systems.  相似文献   
115.
Archaeologists' reconstructions of paths to complexity have all too often excluded complex hunter-gatherers. However, recent theoretical contributions and long-term field research programs in several regions of the world have now significantly advanced our understanding of complex hunter-gatherers. A discussion of definitions of complexity and a review of current models of the emergence of complexity provide a framework for analyses of complex hunter-gatherers and important cultural phenomena such as sedentism, political integration, prestige economies, feasting, and ideology.  相似文献   
116.
Agentes de su propia libertad. Los esclavos de Lima y la desintegración de la esclavitud, 1821–1854. By CARLOS AGUIRRE. Lima: Fondo Editorial Universidad Católica, 1993. Pp. 333.

Slavery and Abolition in Early Republican Peru. By PETER BLANCHARD. Delaware: Scholarly Resources, 1992. Pp. xx, 247.

Paying the Price of Freedom: Family and Labor among Lima's Slaves, 1800–1854. By CHRISTINE HÜNEFELDT. Berkeley: University of California Press, 1994. Pp. xi, 269.

Safari africano y compra‐venta de esclavos para el Perú (1412–1818). By FERNANDO ROMERO. Lima: IEP‐UNSCH, 1994. Pp. 275.  相似文献   

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Glow discharge optical emission spectrometry (GDOES) has been used for obtaining calibration curves for copper, tin, lead, silver, antimony, arsenic, zinc and iron from standards including copper-base alloys (Cu 61.33-99.95%) and from bronze Punic coins. The GDOES results were calibrated using atomic absorption spectroscopy with inductively coupled plasma atomization (ICPAAS) to analyse the standards and coins. For all these materials, the results show that via GDOES it is possible to obtain reliable and reproducible calibration curves for copper, tin, lead, zinc and iron with a linear behaviour as a function of the content. The quantitative GDOES and ICPAAS data for the coins have been also compared with those obtained via X-ray fluorescence (XRF) and it is shown that GDOES, ICPAAS and XRF agree well with one another considering that the bronze coins are inhomogeneous to some degree. As an example of GDOES analytical features, a depth concentration profile through a thin bronze patina is shown and briefly discussed.  相似文献   
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In Part I of this paper (Smith and Hsieh, 1997) a programming formulation of steady states was developed for gravity-type interactive Markov chains in terms of their associated spatial-flow chains. These results are here applied to analyze the stability properties of interactive Markov chains. In particular, the objective function for this programming formulation is shown to constitute a Lyapunov function for an appropriately defined continuous-time version of spatial-flow chains. The Lyapunov stability properties of these spatial flows are then shown to yield corresponding stability properties for the continuous-time versions of interactive Markov chains. In particular, these processes always exhibit global convergence to steady states. Finally, it is shown that when steady states are unique, these convergence results are inherited by those interactive Markov chains that are 'sufficiently close' to their continuous-time versions.  相似文献   
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