Urban growth and transportation

We estimate the effects of major roads and public transit on the growth of major cities in the US between 1980 and 2000. We find that a 10% increase in a city’s stock of roads causes about a 2% increase in its population and employment and a small decrease in its share of poor households over this 20 year period. We also find that a 10% increase in a city’s stock of large buses causes about a 0.8% population increase and a small increase in the share of poor households over this period. To estimate these effects we rely on an instrumental variables estimation which uses a 1947 plan of the interstate highway system and an 1898 map of railroads as instruments for 1980 roads.urban growth, transportation, public transport, instrumental variables

The effects of land transfer taxes on real estate markets: Evidence from a natural experiment in Toronto

Taxes levied on the sale or purchase of real estate are pervasive but little studied. By exploiting a natural experiment arising from Toronto’s imposition of a Land Transfer Tax (LTT) in early 2008, we estimate the impact of real estate transfer taxes on the market for single family homes. Our data show that Toronto’s 1.1% tax caused a 15% decline in the number of sales and a decline in housing prices about equal to the tax. Relative to an equivalent property tax, the associated welfare loss is substantial, about $1 for every$ 8 in tax revenue. The magnitude of this welfare loss is comparable to those associated with better known interventions in the housing market. Unlike many possible tax reforms, eliminating existing LTTs in favour of revenue equivalent property taxes appears straightforward.Land transfer tax, property tax, land regulation

Urban Growth and Transportation

We estimate the effects of interstate highways on the growth of US cities between 1983 and 2003. We find that a 10% increase in a city\u27s initial stock of highways causes about a 1.5% increase in its employment over this 20 year period. To estimate a structural model of urban growth and transportation, we rely on an instrumental variables estimation which uses a 1947 plan of the interstate highway system, an 1898 map of railroads, and maps of the early explorations of the US as instruments for 1983 highways

The Fundamental Law of Road Congestion: Evidence from US cities

We investigate the relationship between interstate highways and highway vehicle kilometers traveled (VKT) in US cities. We find that VKT increases proportionately to highways and identify three important sources for this extra VKT: an increase in driving by current residents; an increase in transportation intensive production activity; and an inflow of new residents. The provision of public transportation has no impact on VKT. We also estimate the aggregate city level demand for VKT and find it to be very elastic. We conclude that an increased provision of roads or public transit is unlikely to relieve congestion.

Roads and Trade: Evidence from the US

We estimate the effect of interstate highways on the level and composition of trade for US cities. Highways within cities have a large effect on the weight of city exports with an elasticity of approximately 0.5. We find little effect of highways on the total value of exports. Consistent with this, we find that cities with more highways specialize in sectors producing heavy goods

Protective Action of Resveratrol in Human Skin: Possible Involvement of Specific Receptor Binding Sites

Background: Resveratrol is a plant-derived polyphenol with purported protecting action on various disorders associated with aging. It has been suggested that resveratrol could exert its protective action by acting on specific plasma membrane polyphenol binding sites (Han Y.S., et al. (2006) J Pharmacol Exp Ther 318:238–245). The purpose of this study was to investigate, in human skin, the possible existence of specific binding sites that mediate the protective action of resveratrol. Methods and Findings: Using human skin tissue, we report here the presence of specific [ 3 H]-resveratrol binding sites (KD = 180 nM) that are mainly located in the epidermis. Exposure of HaCaT cells to the nitric oxide free radical donor sodium nitroprusside (SNP; 0.3–3 mM) resulted in cell death which was reduced by resveratrol (EC50 = 14.7 mM), and to a much lesser extent by the resveratrol analogue piceatannol (EC 50 =95 mM) and epigallocatechin gallate (EC 50 =200 mM), a green-tea derived polyphenol. The protective action of resveratrol likely relates to its anti-apoptotic effect since at the same range of concentration it was able to reduce both the number of apoptotic cells as well as mitochondrial apoptotic events triggered by SNP. Conclusion: Taken together, these findings suggest that resveratrol, by acting on specific polyphenol binding sites i

External economies as a mechanism of agglomeration in EU manufacturing

International audienceProductive externalities are significant determinants of agglomeration, not deeply studied at the industry and international level. We analyse the impact on productivity growth of technological externalities, both inter- and intraindustry, national or international, at the industry level for the European Union (EU) countries and the period 1995-2002. The results confirm the advisability of considering international externalities when countries are takes as regions, whose omission underestimates national spillovers. Together with national endowments and a central geographical position, the growth of productivity is encouraged by national and international specialization as a general result; moreover, it is fuelled by stronger interindustry spillovers and productive diversification, a result more evident for high technology industries, while lower technology industries are more sensitive to the omission of international externalities. Economic integration seems to be relevant, because supranational regions with less friction for goods and factor movements are more likely to take advantage of external economies as a mechanism of productivity growth and agglomeration

Vitamin D and Calcium Supplementation Accelerates Randall's Plaque Formation in a Murine Model

Most kidney stones are made of calcium oxalate crystals. Randall\u27s plaque, an apatite deposit at the tip of the renal papilla, is considered to at the origin of these stones. Hypercalciuria may promote Randall\u27s plaque formation and growth. We analyzed whether long-term exposure of Abcc6 mice (a murine model of Randall\u27s plaque) to vitamin D supplementation, with or without a calcium-rich diet, would accelerate the formation of Randall\u27s plaque. Eight groups of mice (including Abcc6 and wild type) received vitamin D alone (100,000 UI/kg every 2 weeks), a calcium-enriched diet alone (calcium gluconate 2 g/L in drinking water), both vitamin D supplementation and a calcium-rich diet, or a standard diet (controls) for 6 months. Kidney calcifications were assessed by 3-dimensional microcomputed tomography, μ-Fourier transform infrared spectroscopy, field emission-scanning electron microscopy, transmission electron microscopy, and Yasue staining. At 6 months, Abcc6 mice exposed to vitamin D and calcium supplementation developed massive Randall\u27s plaque when compared with control Abcc6 mice (P < 0.01). Wild-type animals did not develop significant calcifications when exposed to vitamin D. Combined administration of vitamin D and calcium significantly accelerates Randall\u27s plaque formation in a murine model. This original model raises concerns about the cumulative risk of vitamin D supplementation and calcium intakes in Randall\u27s plaque formation

Cultural and creative industries and regional diversification:Does size matter?

This paper aims at analysing how the presence of workers employed in cultural and creative industries (CCIs) is related to regional specialized diversification. From a theoretical perspective, CCIs drive economic development and local innovative capacity by facilitating processes of cross-fertilization of ideas. This study estimates an entry model analysing the ability of Italian provinces to successfully create new sectoral specializations. The results indicate that the relationship between the share of employees in CCIs and the probability of creating new sectoral specializations is non-linear, highlighting the need for CCIs-led policies to achieve a certain level of critical mass to be successful