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81.
This article addresses conceptual and measurement challenges that complicate the study of state immigrant policies. First, given the multiple facets of immigrant‐related policy, policy‐specific effects may be obscured by highly aggregated outcomes variables. Second, variables of interest often capture both time‐varying and time‐invariant effects, potentially producing coefficients that are uninterpretable averages of both processes. This article presents a research design that addresses both of these obstacles and applies it to an original dataset of both integrative and punitive policies adopted over the period 2005–16. The findings suggest that the causal roles of growing immigrant populations, partisanship, and wealth vary across different clusters of immigrant policies and that average, cross‐state effects often differ from within‐state effects. Future research would do well to clearly link theoretical expectations to specific types of policy outcomes and test hypotheses over both integrative and restrictive outcomes.  相似文献   
82.
This paper describes the archaeometric research conducted at the SLOWPOKE Reactor Facility of the University of Toronto (SLOWPOKE‐Toronto) during its existence from 1971 to 1998. The contributions to student teaching and research are described, and the total contribution of the facility to studies of an eclectic assortment of ancient and historic materials is addressed.  相似文献   
83.
Archaeological bones, found close to Mexico City (Tlatelcomila), with alterations due to probable thermal exposure attributed to a possible case of cannibalism, have been characterized by XRD, SAXS and SEM. It is shown how these non‐destructive techniques, which are not conventionally used in archaeological research, may provide useful information. The deterioration degree of the bone structure is quantified through parameters such as gyration radius or fractal dimension. As some of the reported modifications could be attributed to diagenesis, a discussion is presented in terms of bone crystallinity and ionic exchange. Furthermore, the hydroxyapatite crystallite size increased depending on colour: this feature is not explained by diagenesis—it can only be attributed to temperature. We conclude that the samples were thermally treated. Indeed, thermal treatment alters the structure and morphology of bone at a very fine level (microscopic and nanometric), while morphology follows the structural modifications. It is determined that the studied human bones were treated at three different temperatures close to 100, 250 and 600°C. Therefore, they were either boiled (barbacoa) or grilled.  相似文献   
84.
The calcareous skeletal remains of various microscopic organisms such as foraminifera and ostracods are a striking feature of thin sections of many archaeological ceramics from the Aegean Bronze Age. While the presence of these calcareous microfossils in pottery has been noted for some time, attempts to utilize them to further the aims of ceramic compositional analysis have been few in number. In the following paper, we take a first detailed look at the occurrence and utility of calcareous microfossils in archaeological ceramics. By presenting selected case studies from the Bronze Age of Crete, we demonstrate the potential of calcareous microfossils, especially the extremely small ‘nannofossils’ and the highly contextual geological information that they contain, in terms of the characterization and grouping of ceramics, the determination of their provenance and the reconstruction of ancient technology.  相似文献   
85.
I. K. BAILIFF 《Archaeometry》2007,49(4):827-851
Fired clay brick samples, obtained from a group of seven high‐status late‐medieval and post‐medieval buildings in England ranging in age from c. ad 1390 to 1740, were dated by the luminescence method using an optically stimulated luminescence (OSL) technique. The results obtained indicate that, when applied to quartz extracted from brick, the technique is capable of producing dates that are in consistently good agreement with independent dating evidence for the buildings. For six samples taken from a group of four dating ‘control’ buildings the mean difference between the central values of luminescence and assigned ages was 5 ± 10 years (SD, n = 6). The methodology used is appropriate for application to other standing buildings in other temporal and geographic regions, and may be used with confidence where conventional dating methods are less certain. The study also examines the luminescence characteristics of quartz and the characteristics of the lithogenic radionuclides in brick samples and identifies various aspects related to the assessment of experimental uncertainty in testing the reliability of the method.  相似文献   
86.
Voluntary environmental programs (VEPs) have been used as a policy tool in the United States since the early 1990s and come in many forms. Early assessments of VEPs targeting changes in production processes showed that industrial participants improved their environmental performance and VEPs were celebrated as a viable alternative to more traditional regulation. Recent analyses using more sophisticated techniques, however, paint a less favorable picture. On the one hand, firms appear willing to sign up to VEPs, and in some cases, participants may be able to create a shield against future losses in shareholder value. On the other hand, these VEPs targeting production processes appear not to generate significant pollution abatement. The latter finding is particularly disturbing and this article discusses various explanations, including institutional failure and participant motivations. Future research needs to focus on understanding the firm motivation to invest in production‐related pollution abatement under a VEP. For policymakers, the research offers a warning on the limited impact to date of VEPs targeting production processes. However, the multitude of other VEPs, such as those which target new product development and changing market demands, merit a closer look to determine the overall potential of VEPs to engender positive environmental change.  相似文献   
87.
Science Cities: What the Concept of the Creative City Means for Knowledge Production. – The article aims to show that the relationship of science and the city has changed since the 1970s in the context of the knowledgeable society. While cities have principally been regarded as the typical space of science, of new ideas and innovation for centuries, since the 1960s and 1970s universities, research institutes as well as industrial research institutes have relocated to the periphery of cities. There, however, these sites of knowledge have been organized in an ‘urban mode’. That means that the concept of the city as a place of science and innovation has determined the architectural, spatial, and social organization of these sites on the periphery of cities. Certain features of the city have been copied, such as social infrastructures, places of communication, restaurants, cafes etc., while others have been left out – housing, cinema, theatre etc. An ‘urban mode of knowledge production’ in the sense of a very stylized model of the city has become a tool to enhance the production of scientific and technological knowledge. – The article exemplifies this by focusing on a case study, namely of the so‐called ‘Science City’ of the Siemens Company in Munich‐Neuperlach.  相似文献   
88.
本文在对琉璃河西周燕国墓地玉器进行考古学研究的基础上,结合文献,对西周燕国玉器的使用制度进行了分析考证,认为燕国在西周早期,以组玉佩和葬玉为代表的与礼制相符的用玉制度已见端倪,在中国玉器发展史上占有重要地位。  相似文献   
89.
90.
Major corrosion has been found at depth in carbonate hydrocarbon reservoirs from different geologic provinces. Fluid inclusion microthermometry and stable isotopic compositions of carbonate cements, predating major corrosion, constrain the interpretation of the evolution of parental fluids during progressive burial and prior to the major corrosion event. Post‐major corrosion mineral paragenesis includes pyrite (‐marcasite), anhydrite, kaolinite (dickite) and fluorite. Although the post‐corrosion mineral paragenesis represents minor volumes of rock, it may provide valuable insights into the post‐corrosion brine chemistry. Using reactive transport numerical models, the roles of cooling and/or mixing of brines on corrosion have been evaluated as controls for dolomitization, deep burial corrosion and precipitation of the post‐corrosion mineral paragenesis. Modelling results show that cooling of deep‐seated fluids moving upward along a fracture may cause minor calcite dissolution and porosity generation. Significant dolomitization along a fracture zone and nearby host‐rock only occurs when deep‐seated fluids have high salinities (4 mol Cl kg?1 of solution) and Darcian flow rates are relatively high (1 m3 m?2 year?1). Only minor volumes of quartz and fluorite precipitate in the newly formed porosity. Moreover, modelling results cannot reproduce the authigenic precipitation of kaolinite (dickite at high temperatures) by cooling. As an alternative to cooling as a cause of corrosion, mixing between two brines of different compositions and salinities is represented by two main cases. One case consists of the flow up along a fracture of deep‐seated fluids with higher salinities than the fluid in the wall rock. Dolomite does not precipitate at a fracture zone. Nevertheless, minor volumes of dolomite are formed away from the fracture. The post‐corrosion mineral paragenesis can be partly reproduced, and the results are comparable to those obtained from cooling calculations. Minor volumes of quartz and fluorite are formed, and kaolinite‐dickite does not precipitate. The major outputs of this scenario are calcite dissolution and slight net increase in porosity. A second case corresponds to the mixing of low salinity deep‐seated fluids, flowing up along fractures, with high salinity brines within the wall rock. Calculations predict major dissolution of calcite and precipitation of dolomite. The post‐corrosion mineral paragenesis can be reproduced. High volumes of quartz, fluorite and kaolinite‐dickite precipitate and may even completely occlude newly formed porosity.  相似文献   
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