Search results for "PLUS"
showing 10 items of 248 documents
Effects of several degrees of chronic social defeat stress on emotional and spatial memory in CD1 mice
2015
In the present study, the effects of several degrees of CSDS (Chronic Social Defeat Stress) on emotional and spatial memory in mice were evaluated in separate experiments. Male CD1 mice were randomly assigned to four experimental groups (n=10-12) for each experiment: NS (non-stressed), S5, S10 and S20 (5, 10 and 20 sessions of CSDS, respectively). The S groups underwent the corresponding number of agonistic encounters (10min each) over a 20-day period. 24h after the last session of CSDS, mice performed the inhibitory avoidance (Experiment 1) or the Morris water maze test (Experiment 2). In both experiments, animals were also evaluated in the elevated plus maze for 5min to obtain complementa…
Inhibitory avoidance learning in CD1 mice: Effects of chronic social defeat stress
2015
Chronic social defeat stress (CSDS) is an animal model widely used to determine the neurobiological mechanisms of stress and its associated pathologies. In this study, the effects of CSDS on inhibitory avoidance (IA) were evaluated in post-pubertal and adult male CD1 mice, instead of the C57BL/6J strain used in the CSDS standard protocol. CSDS consisted of daily 5-min (experiments 1 and 2) or 10-min (experiment 3) agonistic encounters on 21 consecutive days. Twenty four hours after the last session of CSDS, all the mice were tested for IA. They were also evaluated in an elevated plus-maze, obtaining complementary measures of locomotor activity and emotionality. In experiments 1 and 2, IA le…
Cooperation among competitors: A comparison of cost-sharing mechanisms
2016
Abstract In this paper, we investigate the consequences of using outcome-based versus ex ante-based cost-sharing mechanisms in terms of competing firms' profitability and total welfare. We consider two firms making a joint expenditure, which can positively affect firms' demand and/or unit operating costs, while competing in the final market by setting either price or quantity. We compare two outcome-based cost-sharing mechanisms, i.e., Quantity Proportional (QP) and Total Margin proportional (TM), with the more competitive Fixed Share (FS) mechanism where cost-sharing is set up on an ex ante basis. We show that outcome-based mechanisms, and even a fully collusive behavior induced by the opt…
Do microfinance institutions benefit from integrating financial and nonfinancial services?
2017
This article examines the impact of microfinance ‘plus’ (i.e. coordinated combination of financial and nonfinancial services) on the performance of microfinance institutions (MFIs). Using a global data set of MFIs in 77 countries, we find that the provision of nonfinancial services does not harm nor improve MFIs’ financial sustainability and efficiency. The results however suggest that the provision of social services is associated with improved loan quality and greater depth of outreach.
More firms, more competition? The case of the fourth operator in France's mobile phone market
2010
Accepted, Forthcoming; International audience; To foster competition the French government authorized a fourth operator, ‘Free', to enter the country's mobile phone market at the end of 2009 alongside Orange, SFR and Bouygues Telecom (BT), who held respectively one-half, one-third and one-sixth of the market. By using a stylized model of France's phone market, we have examined what we call the regulator's nightmares and dreams. If Cournot competition is in place before Free's entry, minimizing the total profit fails to maximize the consumer surplus and the total surplus; the maximum most realistic price fall is 6.7% compared to three-way competition and could be 1.7% only; if Orange, SFR an…
Wage gaps between the public and private sectors in Spain
1998
Based on data from the last household survey conducted by the Instituto Nacional de Estatistica in 1990-91, we estimate separate earnings equations by sector of employment and gender, treating the choice of employment sector as endogenous. From these results we compare the wage-generating process for each subgroup and identify the returns to human capital of males and females working in the public and private sectors. We then decompose overall wage gaps by sector for each gender in order to measure the contribution of education and other personal characteristics to public-private wage differentials and to evaluate the economic surplus that public sector workers receive compared to their pri…
Alternative pricing regimes in interurban passenger transport with externalities and modal competition
2009
Abstract We develop an interurban passenger transport model with modal competition, where modes are perceived as differentiated products, and capture all major externalities. Our objective is to establish whether alternative regulatory regimes, which may involve road tolls, may lead to a traffic allocation, user welfare, and total welfare that may be closer to the social optimum. An empirical application to interurban Spanish travel is undertaken. We find that the private regime yields the lowest total welfare level: 12.6% below the social optimum level. Optimum pricing requires a toll on car transport of 5.1 cents of per passenger-km, and a price decrease of all other modes, relative to th…
Competing R&D Joint Ventures in Cournot oligopoly with spillovers
2014
This paper considers competition between R&D cartels, whereby prospective Cournot competitors coordinate their R&D decisions in order to maximize joint profit. It studies how R&D activity, aggregate profit, consumer surplus, and social welfare vary as the number of competing cartels varies. It also compares equilibrium with second best R&D, and discusses the policy implications of the results. The results show that the effects of R&D cartel competition depend on the welfare criterion adopted and on whether there are cooperative synergies or not.
Social Housing Conditions Modulate the Long-Lasting Increase in Cocaine Reward Induced by Intermittent Social Defeat
2019
Social defeat is considered the most representative animal model for studying the consequences of social stress. Intermittent social defeat (ISD) has proved to enhance the response to cocaine hedonic properties. In the present research, we evaluated if different social housing conditions, as housing with a familiar conspecific or with a female, exert a protective effect modulating the negative consequences of ISD as the increased sensitivity to cocaine and the induction of anxiety-like behavior. To achieve this objective, non-stressed or ISD OF1 male mice were divided into five different experimental groups according to their social environment: standard housing (four adult males per cage);…
Behavioural Consequences of P-Glycoprotein Deficiency in Mice, with Special Focus on Stress-Related Mechanisms
2012
P-glycoprotein (P-gp), an efflux transporter localised in the blood-brain barrier, limits the access of multiple xenobiotics to the central nervous system. Whether it is also implemented in the transport of the endogenous glucocorticoid corticosterone is a matter of debate. The P-gp knockout mouse model [abcb1a/b (-/-)] has been shown to differ in the functioning of the hypothalamic-pituitary adrenal (HPA) axis. In the present study, we investigated the behaviour of abcb1a/b (-/-) and wild-type mice with respect to stress-related tests and the effects of corticosterone. Behavioural activities were assessed in the open field (OF) test for 4 days, and in the forced swimming test (FST) and tai…