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41.
This paper examines the role of accelerator programmes in promoting transnational entrepreneurship. Designed to assist the growth of start-ups by providing seed finance and structured entrepreneurship support, these programmes are now a prominent feature in many entrepreneurial ecosystems around the world. Drawing on in-depth qualitative evidence focused on one particular programme, the paper shows accelerators play an important intermediary or ‘brokerage mechanism’ providing start-ups with enhanced relational connections and networks. Transnational entrepreneurs attracted to these programmes are highly focused on exploiting these networks whilst maintaining multiple levels of embeddedness in various contexts to maximize the opportunities afforded by accelerators. While many governments are attempting to replicate accelerators programmes within the public sector, the paper concludes that such attempts may prove problematic within weaker entrepreneurial ecosystems.  相似文献   
42.
Cities offer a large menu of possible employment and leisure opportunities. The gains from such consumer city leisure are likely to be lower on more polluted days. We study the association between daily consumption activity and outdoor air pollution in China and find evidence in favor of the hypothesis that clean air and leaving one's home for leisure trips are complements. Given the high levels of air pollution in cities in the developing world, regulation induced improvement in environmental quality is likely to further stimulate demand for the consumer city.  相似文献   
43.
In 1940, Gretchen Cutter and a WPA crew conducted excavations in the Mound Wio5 at the Fisher site in Will County, Illinois. We examined those materials as part of our reanalysis of the Fisher site excavations by George Langford and the University of Chicago. The mound’s material culture correlates with the Des Plaines phase but contains strong connections to the east, especially with Albee phase mortuary practices. Calibrated 14C dates and Bayesian modeling place the Des Plaines phase as contemporary with the Mound Wio5 mortuary’s primary use during the ninth to eleventh centuries. There is isotopic evidence of a mixed C3/C4 diet with some maize consumption. Mound Wio5 represents the only Terminal Late Woodland collective mortuary facility currently known in northeastern Illinois. The identification of such multigenerational communal Terminal Late Woodland mortuary practices lends support to the contention that they provided the cultural base for the emergence of the distinctive Langford Tradition accretional mortuary mounds.  相似文献   
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45.
The paper presents an algorithm for computing the parameters of an ellipse that fits, in a least-squares sense, the surveyed remains of Roman amphitheatre arena walls. The algorithm is validated using ideal data and the near complete remains of the amphitheatre at Sarmizegetusa in Romania. The technique is then applied to the partial remains of the amphitheatre at the Guildhall in the City of London, in the UK, which cover only the Eastern end of the monument. The underlying mathematical model and method of solution is presented. The method was developed with a view to determining firstly whether or not an ellipse is a feasible model for the actual constructed curve geometry, and secondly, where the Western end of the Guildhall amphitheatre might be located. One single ellipse was found to fit the Guildhall remains, with measurement residuals at the level of 30 mm in the eastings and 26 mm in the northings. The ellipse had a semi-major axis of 28.345 m and a semi-minor axis of 22.775 m. The issues of alternative geometries and the practicalities of their use in construction are considered.  相似文献   
46.
This study examines preservation of microfossils identified as introduced Ipomoea batatas in soils from northern New Zealand. Starch grains and xylem cells showed highly variable preservation, from good to extremely poor. For starch grains, the latter included brown-staining, expansion and distortion of the grain and vacuole, loss of the Maltese cross, pitting, cracking, fragmentation and disintegration. Degraded xylem showed similar brown-staining, occasional cracking, cross-wise fragmentation, with wall pits becoming progressively less visible or showing distortion, expansion and coalescence.  相似文献   
47.
This article presents the restitution of an operation of excavation carried out in 1937 by Moreau Chambers on the site of a Chickasaw village. The objective of my research is to carry out a new analysis of the documents of the old excavations, to answer the interrogations concerning the way of life of Chickasaw at the beginning of the historical period and to reconstitute a site plan for this Chickasaw village. This operation included/understood also the handing-over of repatriated bodies. I also discuss the way in which my implication in this project interacted with my identity as a Chickasaw woman. The restitution of the operation of excavation, repatriation, and associated research contributed to show to the Chickasaw people the ways in which the law can help them. I finish this article by discussing the implications on the long term of the operation of Chambers for the modern archaeologists, the Chickasaw people, and Chickasaw who are themselves archaeologists.  相似文献   
48.
The difficulty of distinguishing between loose first and second mandibular molars of domestic cattle (BOS taurus) from archaeological sites is well known. This paper proposes cervical length as a discriminatory measurement. The possibility that cervical measurements of first and second mandibular molars may be sexually dimorphic is also explored.  相似文献   
49.
Book reviews     
The Solitary Self: Jean‐Jacques Rousseau in Exil and Adversity. By Maurice Cranston (Chicago, IL: University of Chicago Press, 1997) xii + 247 pp. $29.95 cloth.

The Self‐Aware Image: An Insight into Early Modern Meta‐Painting. By Victor I. Stoichita (Cambridge: Cambridge University Press, 1997) xv + 345 pp. $85.00, £55.00 cloth.

The Cambridge Companion to Nietzsche. Edited by Bernd Magnus and Kathleen M. Higgins (Cambridge: Cambridge University Press, 1996) ix + 403 pp. $18.95, £13.95 paper, $59.95, £40.00 cloth.

David Hume: Political Essays. Edited by Knud Haakonssen, Cambridge Texts in the History of Political Thought (Cambridge: Cambridge University Press, 1994) lxvi + 346 pp. $49.95, £30.00 cloth, $15.95, £10.95 paper.

Sartre, Foucault, and Historical Reason. By Thomas R. Flynn (Chicago and London: The University of Chicago Press, 1997) 340 + xvi pages. $18.95 paper.

Shaping World History: Breakthroughs in Ecology, Technology, Science, and Politics. By Mary Kilbourne Matossian (Armonk, NY: M.E. Sharpe, 1997) 264 pp. $62.95 cloth, $22.95 paper.  相似文献   

50.
Based on existing work, there are clear differences in the incidence of degree holders across the urban–rural hierarchy in favor of large urban areas. In large part, this gradient can be traced to the higher probability of obtaining a degree among residents of larger urban centers. Utilizing data from the Youth in Transition Survey (YITS), this paper explores factors that may account for university participation among Canadian youth. It asks whether this difference is due to local access to universities, family characteristics (e.g., parental income, education, and immigrant status), and local labor market characteristics that may increase the incentive for urban youth to attend university.  相似文献   
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