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991.
992.
Since the early 1990s, the Environmental Protection Agency (EPA) has struggled to make Superfund, the program that addresses the nation's worst hazardous waste sites, "faster, fairer, and more efficient." Indeed, agency figures reflect substantial changes in recent years. Since 1993, over 500 Superfund sites have reached the "construction completion" stage in remediation. Comparatively, in the program's first 13 years, only 156 sites reached construction completion. This article explores why some Superfund sites are more likely to be remediated than others. We use survival analysis to empirically test three theoretical models of Superfund remedial progress: (1) Administrative Convenience/Transaction Costs; (2) Problem Severity; and (3) Political Pressure models. The results indicate that the EPA is more likely to tackle "easier" or low-risk sites within the program, community involvement in Superfund is associated with decreased remedial progress, and remedial action is more likely to occur when political oversight is present. 相似文献
993.
The 1996 Personal Responsibility and Work Opportunity Reconciliation Act (PRWORA) marked the continued devolution of social policy to state and local government in addition to restructuring an ailing welfare system. Despite concerns that welfare recipients would find greater obstacles to economic stability as a result, declining welfare rolls have been accompanied by declining poverty rates over the past seven years. An important question is whether low‐income families have gained greater employment and housing capacity following welfare reform. Moreover, does capacity vary across states with different welfare policies? In addition, do families face greater economic vulnerability with respect to food scarcity and health care? This article uses the data from the 1997 and 1999 waves of the National Survey of America's Families to systematically assess differences in capacity and vulnerability among lower income families across different policy regimes. Using two measures of capacity for housing and employment, and quality of life, findings suggest that more stringent welfare rules are related to greater job and housing attainment but a reduced quality of life. 相似文献
994.
Christine D. White Michael W. Spence Fred J. Longstaffe Kimberley R. Law 《Journal of Anthropological Archaeology》2004,23(4):15
Mechanisms for the maintenance of Zapotec ethnicity in Tlailotlacan, an enclave of Teotihuacan, Mexico, are reconstructed using oxygen-isotope analyses of bone and enamel phosphate. The data indicate continual interaction among the enclave inhabitants, their Oaxacan homeland, and other diaspora colonies, with no dominant post-marital residence pattern. There is no apparent association between social status and place of origin, and individual agency is indicated by variable acceptance of Teotihuacan traditions. Striking patterns of movement include the sojourning of children in other regions and the relocation of breastfeeding women. These segments of the population would have played major roles in the social and political articulation of diaspora colonies. Foreign signatures in primary burials indicate that some immigrants died shortly after their arrival in Tlailotlacan. Data from secondary burials indicate the transportation of dead relatives or ancestors to Teotihuacan for burial. We conclude that the behaviour of immigrants in ancient and modern cities is analogous in many ways. 相似文献
995.
ON STATISTICAL APPROACHES TO THE STUDY OF CERAMIC ARTEFACTS USING GEOCHEMICAL AND PETROGRAPHIC DATA*
M. J. BAXTER C. C. BEARDAH I. PAPAGEORGIOU M. A. CAU P. M. DAY V. KILIKOGLOU 《Archaeometry》2008,50(1):142-157
The scientific analysis of ceramics often has the aim of identifying groups of similar artefacts. Much published work focuses on analysis of data derived from geochemical or mineralogical techniques. The former is more likely to be subjected to quantitative statistical analysis. This paper examines some approaches to the statistical analysis of data arising from both kinds of techniques, including ‘mixed‐mode’ methods where both types of data are incorporated into analysis. The approaches are illustrated using data derived from 88 Late Bronze Age transport jars from Kommos, Crete. Results suggest that the mixed‐mode approach can provide additional insight into the data. 相似文献
996.
L. A. ORTEGA M. C. ZULUAGA A. ALONSO‐OLAZABAL M. INSAUSTI A. IBÁÑEZ 《Archaeometry》2008,50(3):387-408
Chemical and mineralogical analyses were carried out on historical lime mortars from the parish church of Santa María La Real (Guipúzcoa). The study included various periods ranging from Roman to modern times and allowed the identification of various types of raw materials. In order to obtain pure binder, free of carbonate aggregates and charcoal particles, an innovative binder separation method was implemented. The chemical composition of the binder allows discrimination of different provenance areas for the raw materials, although those areas do not correlate with specific historical periods. In addition, the influence of burial processes on the primeval chemical features has been assessed and reveals that modern mortars display greater chemical modification than the Roman mortars. 相似文献
997.
This paper reports an updated and enlarged archaeometric database of Proconnesos marbles with the aim of attaining more reliable inter‐ and intra‐site identification. Quarry and artefact samples (n = 397) from 23 different quarrying areas were characterized using petrographic, isotopic and EPR results. The most distinct property of Proconnesos marbles is their extremely weak EPR intensity, associated with the low concentration of Mn2+impurities. This feature, supported by the contribution of other important isotopic and petrographic variables, forms the basis for the correct identification of Proconnesos marbles. Within the site the distribution of properties is relatively homogeneous; only limited intra‐site discrimination is possible. All the experimental results, as well as the quarry samples are made available to other researchers willing to measure additional experimental properties, thus increasing the rate of within the site discrimination. Extensive survey has proved that, although about 10% of the samples exhibit maximum grain size below 1.0 mm, no locations exist where fine grained marbles could be intentionally quarried. The historical aspects of Proconnesos marble quarrying and usage are also discussed. 相似文献
998.
M. F. GUERRA 《Archaeometry》2008,50(6):951-967
Artefacts and works of art kept in museum collections originated in many cases from ancient private collections. In such cases, a partial or total absence of historical information may create additional problems concerning their authenticity. The study of museum collections and their preservation requires the use of analytical techniques but also combined examination techniques not commonly necessary for the study of archaeological objects. This paper gives an overview of the importance of museum items for the understanding of the past, the difficulties relating to their authentication and the significant advances brought about by science‐based techniques, in particular those cases discussed in Archaeometry during the past 50 years. 相似文献
999.
N. BRIANESE U. CASELLATO F. FENZI M. MENDERA B. MESSIGA L. NODARI M. P. RICCARDI P. A. VIGATO 《Archaeometry》2008,50(5):775-796
This study deals with the physical–chemical and mineralogical–petrographic investigations (OM, SEM–EDS, EPMA, ICP, XRpD, Mössbauer and IR) conducted on first‐ and second‐firing wasters belonging to two types of incised slipware (sgraffito), manufactured at Castelfiorentino between the late 15th and the early 17th centuries. Raw materials, colouring agents and firing products were analysed in order to establish the production technology of the ceramic coatings, by means of detailed microtextural and chemical investigations. The pottery underwent two firing processes: the firing of the white slip‐coated ceramic body and a further firing after application of the glaze. The homogeneity of the raw materials, white slip and glaze is remarkable, and demonstrates the use of well‐established recipes with a constant supply of raw materials from the same places. Highly efficient kiln management during both firings is revealed by body–glaze interface reactions. 相似文献
1000.
L. DUSSUBIEUX C. M. KUSIMBA V. GOGTE S. B. KUSIMBA B. GRATUZE R. OKA 《Archaeometry》2008,50(5):797-821
The occurrence of similar glass beads at archaeological sites in Africa and Asia bears witness to the trade relationship between the two continents. This paper reports elemental analysis results from a recent in‐depth laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) study of a group of archaeological glass beads with a specific alumina‐rich composition from East Africa, India and Sri Lanka. Based on the concentrations of the trace elements, two different subgroups were identified. One subgroup occurs at early periods (fourth century bce to fifth century ace ) in South India and Sri Lanka. The second subgroup appears at later dates in Africa and was identified at different Kenyan sites dated from the ninth to the 19th century ace , and at the contemporaneous site of Chaul in western India. 相似文献