Food-induced behavioral sensitization, its cross-sensitization to cocaine and morphine, pharmacological blockade, and effect on food intake

Repeated administration of abused drugs sensitizes their stimulant effects and results in a drug-paired environment eliciting conditioned activity. We tested whether food induces similar effects. Food-deprived male mice were given novel food during 30 min tests in a runway (FR group) that measured locomotor activity. Whereas the activity of this group increased with repeated testing, that of a group exposed to the runways but that received the food in the home cage (FH group), or of a group satiated by prefeeding before testing (SAT group), decreased. When exposed to the runways in the absence of food, the paired group was more active than the other groups (conditioned activity); no activity differences were seen in an alternative, non-food-paired, apparatus. Conditioned activity survived a 3-week period without runway exposure. Conditioned activity was selectively reduced by the opiate antagonist naltrexone (10-20 mg/kg) and by the noncompetitive AMPA receptor antagonist GYKI 52466 [1-(4-aminophenyl)-4-methyl-7,8-methylenedioxy-5H-2,3-benzodiazepine hydrochloride] (5-10 mg/kg). The D1 antagonist SCH23390 [R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrochloride] (15-30 microg/kg) and D2 antagonist sulpiride (25-125 mg/kg) reduced activity nonspecifically. A single intraperitoneal dose of cocaine (10 mg/kg) or morphine (20 mg/kg) increased activity compared with saline, the stimulant effect being larger in the FR group, suggesting "cross-sensitization" to these drugs. However, pretreatment with GYKI 52466 or naltrexone at doses that suppressed conditioned activity in FR animals suppressed cross-sensitization to cocaine. When allowed ad libitum access to food in the runway, FR mice consumed more pellets in a time-limited test. Thus, many of the features of behavioral sensitization to drugs can be demonstrated using food reward and may contribute to excessive eating

SPATIAL AND SECTORAL PRODUCTIVITY CONVERGENCE BETWEEN EUROPEAN REGIONS, 1975-2000

This paper analyzes the evolution of labor productivity disparities among 145 European regions over 1975-2000 according to the concepts of ƒã- and ƒÒ-convergence and emphasizes the importance of including spatial effects and a disaggregated analysis at a sectoral level. We detect a significant -convergence only in aggregate labor productivity and in the services sectors among peripheral regions. We also show that omitting spatial effects leads to biased measures of -convergence. We then estimate a pooled -convergence model including spatial autocorrelation and sectoral differentiation. The results indicate that disparities in productivity levels between core and peripheral regions persist by vary by sector.convergence, spatial econometrics, labor productivity, sectoral approach

REGIONAL CONVERGENCE AND THE IMPACT OF EUROPEAN STRUCTURAL FUNDS OVER 1989-1999: A SPATIAL ECONOMETRIC ANALYSIS

This paper estimates the impact of structural funds on the convergence process between 145 European regions over 1989-1999. Since the majority of these funds finance transportation infrastructures, they induce spillover effects, industry relocation and do not necessarily succeed in reducing regional inequalities. To estimate their impact, including spillover effects, we first apply spatial econometrics on a conditional beta-convergence model; second, we simulate their impact on the targeted region and then on all the other regions. The results show that structural funds have positively benefited to the targeted regions’ growth, but that spillover effects are very small in peripheral regions.European structural funds, beta-convergence, spatial econometrics, geographic spillovers

THE DIFFERENTIAL IMPACT OF FEDERAL AND STATE MINIMUM WAGES ON TEENAGE EMPLOYMENT

The "new economics of the minimum wage" is based on the findings from case studies that minimum wages had no effect on employment and may even have increased it. This conclusion is at odds with the findings of earlier studies and those of a number of more recent studies which find a statistically significant negative effect on teenage employment. These conflicting results constitute a puzzle. We find that this is due to minimum wage hikes implemented at the state-level having no negative effects on teenage employment during the 1980s and 1990s, while the federal hikes of the 1990s did. In states without their own minimum wages, the decline in the relative value of the federal minimum wage during the 1980s gave rise to an increase in low-wage employment that was subsequently checked and reversed by the federal hikes in the early 1990s.Federal Minimum Wages; State Minimum Wages; Teenage Employment

The Impact of EU Regional Support on Growth and Employment

In this paper the authors assess the impact of structural funds on the per capita GDP and employment convergence process of 145 European regions over 1989–1999. This paper goes beyond the recent contributions on European regional policies and convergence since each of the five objectives of regional support is studied and spatial effects are included in the analysis. For this purpose the authors use spatial econometrics to include the relevant spatial effects in the estimation of the appropriate conditional ß-convergence model. The impact of the funds and their spatial lag indicate few significant results, and when they are, their extent is very small or even negative. This raises some doubts on the efficiency of regional support and call for a deep reform for the next programming period.European structural funds, ß-convergence, growth, employment, spatial econometrics, geographic spillovers

Spatial econometric analysis of the evolution of the European regional convergence process, 1980-1999

beta-convergence, convergence clubs, European regions, spatial econometrics

THE DIFFERENTIAL IMPACT OF FEDERAL AND STATE MINIMUM WAGES ON TEENAGE EMPLOYMENT

The "new economics of the minimum wage" is based on the findings from case studies that minimum wages had no effect on employment and may even have increased it. This conclusion is at odds with the findings of earlier studies and those of a number of more recent studies which find a statistically significant negative effect on teenage employment. These conflicting results constitute a puzzle. We find that this is due to minimum wage hikes implemented at the state-level having no negative effects on teenage employment during the 1980s and 1990s, while the federal hikes of the 1990s did. In states without their own minimum wages, the decline in the relative value of the federal minimum wage during the 1980s gave rise to an increase in low-wage employment that was subsequently checked and reversed by the federal hikes in the early 1990s.Federal Minimum Wages; State Minimum Wages; Teenage Employment

The impact of objective and subjective measures of air quality and noise on house prices: a multilevel approach for downtown Madrid

Air quality is one of the major concerns in big cities. It is therefore of interest to evaluate properly air pollution. Specifically, this paper aims at measuring how air quality is incorporated in transaction prices in downtown Madrid. For that purpose, we use multilevel models since our sample is hierarchically organized into 3 levels. Our first-level consists of 5,080 house prices. The second level consists of 759 census tracts while the third level consists of 43 neighbourhoods. We have variables available for each level, individual characteristics for the first level and various socio-economic data for the other levels. The outline of the paper is as follows. First, we combine a set of noise and air pollutants measured at a number of monitoring stations available for each census tract. Second, we apply kriging to match the monitoring station records to the census data. Third, we estimate hedonic models in order to measure the marginal willingness to pay for air quality in downtown Madrid. While the conventional approach to estimate hedonic models is to use ordinary least squares, we exploit the hierarchical nature of our data and estimated multilevel models instead. These allow for a more reliable statistical inference.

Evaluating the temporal and the spatial heterogeneity of the European convergence process, 1980-1999

In this paper, we suggest a general framework that allows testing simultaneously for temporal heterogeneity, spatial heterogeneity and spatial autocorrelation in beta-convergence models. Based on a sample of 145 European regions over the 1980-1999 period, we estimate a Seemingly Unrelated Regression model with spatial regimes and spatial autocorrelation for two sub-periods: 1980-1989 and 1989-1999. The assumption of temporal independence between the two periods is rejected and the estimation results highlight the presence of spatial error autocorrelation in both sub-periods and spatial instability in the second sub-period, indicating the formation of a convergence club between the peripheral regions of the European Union.beta-convergence models, spatial autocorrelation, convergence clubs, temporal instability

THE SPATIAL DIMENSION OF SEGREGATION - A CASE STUDY IN FOUR FRENCH URBAN AREAS, 1990-1999 *

Over the post-war period, urban growth has exhibited complex spatial patterns including both population spread and employment suburbanization from the central city towards the suburbs, both in US and European metropolitan areas. An important literature, based on North-American metropolitan areas, has also highlighted the strong link existing between this process of suburbanization and the reinforcement of socio-spatial segregation against poor populations living in the central cities (Kain, 1992; Ihlandfeldt and Sjoquist, 1998). On the contrary, European cities do not usually follow this pattern: populations with high income remain localized in and near the city center while urban sprawl mainly concerns households with modest incomes. While the intensity and characteristics of spatial segregation has been extensively documented for US urban areas (Cutler and Glaeser, 1997) and mainly concerns segregation along the ethnic dimension (Taeuber and Taeuber, 1965; Massey and Denton, 1993), studies investigating the specificities of the segregation phenomenon in European cities in general, and French cities in particular, remain scarce (Rhein, 1998; Guermond and Lajoie, 1999; Préteceille, 2001). In this context, the aim of this paper is to analyze the intra-urban spatial segregration in terms of nationality, employment, socio-professional categories and income in four French urban poles: Paris, Lyon, Bordeaux and Dijon. More precisely, we are interested in answering the following questions. First, how does spatial segregation vary for these different measures and across the four urban poles? Second, what are the spatial patterns of segregation within each urban pole? In order to answer these questions, two steps are necessary. The first step involves computing global segregation indices for the different variables and urban poles. In particular, we focus on the Duncan and Duncan’s (1955) segregation and dissimilarity indices and their spatial versions (Wong, 1993), White’s (1983) index and Gini’s measure. Since these measures are global, the second step consists in identifying the spatial patterns involved. In that purpose, we compute entropy indices, which are local segregation indices that reflect the diversity within each unit and that can be mapped to show the spatial variations of segregation among the units of the four urban poles. The paper is organized as follows. First, we discuss the measures of spatial segregation used in this paper. Then we present the study areas, the data and the spatial weight matrix used to perform the analysis. The empirical results are divided in two parts: first, we compute global measures of spatial segregation for nationality, employment, socio-professional categories and income for our four urban poles and second, we display the local spatial segregation indices.