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91.
Significant political and economic developments among the Chumash of southern California were catalyzed in part by the emergence of an intensive, specialist-driven shell-bead industry during the second millennium CE on the Santa Barbara Channel Islands. The production of millions of beads depended in turn on the availability of lithic microdrills of standardized form and materials. Channel Islanders quarried a particular stone type, a blocky Monterey Formation chert, from multiple outcrops situated close to the eastern shores of Santa Cruz Island. Rich archaeological assemblages document the lithic and shell byproducts of these intertwined production systems, each of which endured for several centuries (CE 1150–1819). Islanders invariably chose Island chert for making microdrills: hundreds of thousands of specimens recorded to date are of this material. Furthermore, nearly every microlith in all of Chumash territory (post CE 1150) was produced on the islands; the large populations on the mainland did not participate in microlith making or bead making after CE 1150–1200. We argue that this pattern had its roots not only in the patchiness of key resources and shifting regional social relationships, but also in the physical properties of available raw materials. Here we experimentally assess the properties of Santa Cruz Island chert alongside three important mainland raw materials—Grimes Canyon fused shale, Coso obsidian, and Vandenberg chert—that potentially could have been tapped to make microliths. We test the proposition that Island chert outperforms other lithic materials in drilling efficiency and drill use life. Our experimental results from 108 drilling trials reveal sharp distinctions in performance characteristics across the four materials. We infer that the process by which Islanders became the more-or-less exclusive manufacturers of shell-bead currency in southern California was facilitated by both the efficacy and physical properties of the Island cherts and the propitious locations of the outcrops. 相似文献
92.
Proterosuchid archosaur remains from the Early Triassic Bulgo Sandstone of Long Reef,New South Wales
Benjamin P. Kear 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):331-337
Two associated anterior dorsal vertebrae of a primitive archosaur are described from the Early Triassic (Dienerian–Spathian) Bulgo Sandstone at Long Reef, New South Wales, Australia. Character states including anteroposteriorly elongate centra, dorsal neural spines with height greater than length, the possible presence of intercentra, double-headed rib articulations and well-developed apical tables on the neural spines suggest affinity with proterosuchid archosauriforms and permit some comparisons with previously described Australian taxa. The Bulgo Sandstone vertebrae represent the first record of archosaurian body fossils from the Sydney Basin and are one of only a handful of occurrences thus far documented from the Triassic of Australia. 相似文献
93.
Benjamin P. Kear 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):273-279
Pterosaur remains are very rare in Australasia and especially in Upper Cretaceous strata. Thus, the discovery of a jaw fragment from the Cenomanian–Coniacian Molecap Greensand near Gingin in Western Australia represents an important new stratigraphical occurrence for the region. Although the teeth are not preserved, the presence of labio-lingually compressed alveoli that are anterolaterally oriented, variable in shape/size (inferring heterodonty) and very widely spaced is reminiscent of ornithocheirids—a geographically cosmopolitan clade of predominantly Early Cretaceous pterodactyloids. If correct, this identification could extend the known range of Ornithocheiridae through to the Late Cretaceous in the Southern Hemisphere. 相似文献
94.
The changing dynamics of regional and local labor markets during the last decades have led to an increasing labor market segmentation and socioeconomic polarization and to a rise of income inequalities at the regional, urban, and intraurban level. These problems call for effective social and local labor market policies. However, there is also a growing need for methods and techniques capable of efficiently estimating the likely impact of social and economic change at the local level. For example, the common methodologies for estimating the impacts of large firm openings or closures operate at the regional level. The best of these models disaggregate the region to the city (Armstrong 1993; Batey and Madden 1983). This paper demonstrates how spatial microsimulation modeling techniques can be used for local labor market analysis and policy evaluation to assess these impacts (and their multiplier effects) at the local level‐to measure the effects on individuals and their neighborhood services. First, we review these traditional macroscale and mesoscale regional modeling approaches to urban and regional policy analysis and we illustrate their merits and limitations. Then, we examine the potential of spatial microsimulation modeling to create a new framework for the formulation, analysis and evaluation of social and local labor market policies at the individual or household level. Outputs from a local labor market microsimulation model for Leeds are presented. We show how first it is possible to investigate the interdependencies between individual's or households labor market attributes at the microscale and to model their accessibilities to job opportunities in different localities. From this base we show how detailed what‐if microspatial analysis can be performed to estimate the impact of major changes in the local labor market through job losses or gains, including local multiplier effects. 相似文献
95.
Benjamin Marquez 《政策研究杂志》1985,14(1):170-177
Books reviewed in this article:
Vernon M. Briggs, Jr. Immigration Policy and the American Labor Force .
Vernon M. Briggs, Jr. and Martha Tienda, eds. Immigration: Issues and Policies .
Elizabeth Hull. Without Justice for All: The Constitutional Rights of Aliens .
Milton Morris. Immigration: The Beleaguered Bureaucracy . 相似文献
Vernon M. Briggs, Jr. Immigration Policy and the American Labor Force .
Vernon M. Briggs, Jr. and Martha Tienda, eds. Immigration: Issues and Policies .
Elizabeth Hull. Without Justice for All: The Constitutional Rights of Aliens .
Milton Morris. Immigration: The Beleaguered Bureaucracy . 相似文献
96.
97.
98.
Benjamin P. Kear 《Alcheringa: An Australasian Journal of Paleontology》2018,42(2):155-156
99.
Benjamin Gray 《History of European Ideas》2018,44(6):719-742
ABSTRACTThis paper examines ideas of individual freedom in the Hellenistic city-states (c. 323–31 BCE). It concentrates on the civic ideas expressed in the laws and decrees of Hellenistic cities, inscribed on stone, comparing them with Hellenistic historical and philosophical works. It places different Hellenistic approaches alongside modern liberal, neo-Roman republican and civic humanist theories of individual liberty, finding some overlaps with each of those modern approaches. The argument is that the Hellenistic Greeks developed innovative ways of combining demanding ideals of civic virtue and the common good with equally robust ideals of individual freedom and ethical choice. They did so not least by adapting and developing traditional Greek approaches close to modern civic humanism, in ways very relevant to modern debates about how to reconcile civic duty, the common good and pluralism. 相似文献
100.