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11.
A range of archaeological and palaeoclimatic studies use isotopic analyses of ungulate hypsodont tooth enamel. Such studies commonly assume a constant growth rate, though this has not been fully tested. Here, we use stable isotope analyses of sequential enamel samples to study horse tooth growth. We fit the data using models corresponding to constant and exponentially decreasing rates of growth, and compare the results to metrical data showing the geometry and timing of apposition. The results indicate enamel apposition and maturation advances at an exponentially decreasing rate. An understanding of this variable growth rate is crucial for interpreting isotopic data from equid teeth.  相似文献   
12.
There is a common perception that infrastructure megaprojects are difficult to implement, as they face many obstacles (cost overruns, political barriers and time delays). This was particularly the case in the UK where many projects were difficult to develop given a complex, centralized and turbulent financial context (e.g. the jubilee Line extension, the Eurostar project). Despite this complex British system, London is developing the Crossrail mega infrastructure project which is recognized to be on time and built within a planned budget. The paper aims to analyse the reasons for the development of this project in a turbulent political and financial British system. The main argument I defend is that Crossrail benefited from the constitution of a specific and localized growth coalition. Revisiting the notion developed by Logan and Molotch, I show how the aggregation of different interests (political and economic) has been essential in the concretization of this project. Actors motivated by the will to promote the growth of London and to sustain the growth of population and jobs have been at the forefront to defend Crossrail. These elements have put Crossrail on a route of success. The paper concludes by characterizing and analysing such a success.  相似文献   
13.
This paper analyzes the influence of transportation infrastructure, and in particular of the Regional Express Rail (RER), on employment and population growth in the Paris metropolitan area between 1968 and 2010. In order to make proper causal inference, we rely on historical instruments and control for all other transportation modes that could be complement or substitute to the RER. Our results show that proximity to an RER station increases employment and population density and, in particular, employment and population growth. The latter effects are higher in municipalities located near RER stations and close to employment (sub)centers. They are also found to be particularly strong for jobs in the service sector, for factory workers, and for highly educated population. We find no impact of the RER expansion on employment growth during the first part of the period, while the effect on population growth appears earlier but declines over time.  相似文献   
14.
This article constructs long-span time series indices on wages in Denmark and explores the growth in living standards in the pre-industrial era. There were several persistent upward and downward trends in real annual earnings from 1500 to 1820, but no clear upward long-term trend. This finding seems hard to reconcile with Maddison's figure for the average annual growth in real GDP per capita in Denmark (0.17%) over the same period. This is the case, even if the growth rate in pre-industrial annual earnings is underestimated by 0.05%–0.06% per annum due to an increased number of working days.  相似文献   
15.
16.
A noted specialist on the Russian economy presents an assessment of the impact of the global financial crisis on the mechanism of the country's economic growth. Focusing on the demand side of the economic ledger, the author explores the question of whether Russia will be able to re-attain the high economic growth rates of the period from 2000 to 2007 after recovering from the crisis. The paper analyzes the sharp drop in production in 2008 and the first quarter of 2009, attributing most of the damage to liquidity problems and declines in the price of oil. Empirical evidence is based primarily on data collected by the author from the Central Bank of Russia and the country's federal bureau of statistics (Rosstat). Journal of Economic Literature, Classification Numbers: E010, E200, E660, F210, G010. 11 figures, 3 tables, 29 references.  相似文献   
17.
A noted European economist argues that the Russian economy and its post-2000 growth have been heavily dependent on natural resources, especially hydrocarbons, and are bound to remain so for some time to come. Given that many economists have come to view rich natural resource endowments as a "curse" that undermines development, the question arises as to whether Russian economic development is doomed. The author argues that while the challenges posed by resource dependence are serious, they can be overcome, or at least substantially mitigated, if accompanied by the right economic policies as the examples of Australia, Canada, and the Scandinavian countries demonstrate. He analyzes what these economic policies are for Russia, and how to set up Russian economic and political conditions to facilitate their implementation. Journal of Economic Literature, Classification Numbers: E6, O1, O52, P2, Q43. 4 figures, 2 tables, 50 references.  相似文献   
18.
Using a survey on Italian graduates, we investigate whether universities' degree production affects the economic development of the regions where academic institutions are located. To deal with suspected endogeneity between human capital development and economic growth, we employ an instrumental variable approach, using a global lump sum transferred to each university as an instrument for human capital production. Once we control for the regional flow of mobile students and graduates, the findings reveal the beneficial effect of the university system on local economic development through the gain in human capital.  相似文献   
19.
The concept of social capital is widely perceived as a promising tool for explaining differences in economic development between countries and regions. According to this theory, weak links (bridging social capital) and social trust in an area favour its better access to other forms of capital, that is, economic and human capital. However, strong links (bonding social capital) may stifle creativity and entrepreneurship. Since the vast majority of research on the impact of social capital on economic development focuses on highly developed Western European countries, it seems particularly interesting to evaluate the usefulness of this approach when applied to post‐communist countries with their different experiences. The objective of this article is to identify the spatial variation of different forms of social capital in regions of Poland and then to test a hypothesis on the impact of this capital on regional economic development. The results demonstrate that despite the existing differences between regions there are no significant relationships between levels of social capital and economic development. This may be explained either by low social capital levels or by the overall degree of Polish economic development.  相似文献   
20.
The abundance, accessibility and value of limpets as a source of food and bait for coastal peoples have resulted in their high frequency in shell middens worldwide. The limpet Patella vulgata is found in middens from the Mediterranean to Norway, and morphometric and sclerochronological analyses of its shell can provide insight into harvesting patterns and paleoenvironmental variables valuable in reconstructing climate. Previous work with P. vulgata has relied on lines on the exterior of the shell, or on lines exiting on the shell surface in shell cross-section, as annual or sub-annual markers. Shell damage may compromise these lines and limit the use of some shells, but growth lines are also found in the better-preserved shell apex. We investigated whether the growth lines in the apex of P. vulgata from two locations in Northern Europe are annual using calcein-marking and recapture. Investigations were performed at one site in the Shetland Islands (UK) and at one site at the northern limit of P. vulgata's range in Northern Norway. We also used laser ablation to measure the concentration of minerals in the shells of two individuals from Shetland to determine if patterns of minerals suggested as bioproxies for temperature and productivity varied annually. All individuals deposited one growth line in the apex during their year in the field, and the lowest ratios of Sr/Ca and Ba/Ca and to a lesser extent Mg/Ca were coincident with annual lines on the shells from Shetland. Growth at both sites was modelled using the von Bertalanffy growth function, and apex growth was nearly five times faster in Shetland than in Norway, probably a result of differences in temperature between the two locations.  相似文献   
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