Low smoking-exposure, the adolescent brain, and the modulating role of CHRNA5 polymorphisms

© 2019 Background: Studying the neural consequences of tobacco smoking during adolescence, including those associated with early light use, may help expose the mechanisms that underlie the transition from initial use to nicotine dependence in adulthood. However, only a few studies in adolescents exist, and they include small samples. In addition, the neural mechanism, if one exists, that links nicotinic receptor genes to smoking behavior in adolescents is still unknown. Methods: Structural and diffusion tensor magnetic resonance imaging data were acquired from a large sample of 14-year-old adolescents who completed an extensive battery of neuropsychological, clinical, personality, and drug-use assessments. Additional assessments were conducted at 16 years of age. Results: Exposure to smoking in adolescents, even at low doses, is linked to volume changes in the ventromedial prefrontal cortex and to altered neuronal connectivity in the corpus callosum. The longitudinal analyses strongly suggest that these effects are not preexisting conditions in those who progress to smoking. There was a genetic contribution wherein the volume reduction effects were magnified in smokers who were carriers of the high-risk genotype of the alpha 5 nicotinic receptor subunit gene, rs16969968. Conclusions: These findings give insight into a mechanism involving genes, brain structure, and connectivity underlying why some adolescents find nicotine especially addictive

Statistical Matching in agricultural economics: how to integrate different farm data sources

This study approaches the challenge of integrating different farm data sources by exploiting all the information that researchers already have at disposal. Indeed, due to privacy claim constraints, time-demanding data releasing procedures, etc. farm elementary data are often either partially available or difficult-to-find. In addition, collecting new data can be both highly expensive and time-demanding. A suitable solution is then to aggregate different data sources which are easily and/or already available. This work attempts to deal with both farm data shortage and the characteristics of the observational studies research context. Indeed, we integrate farm data resorting to the non-parametric micro SM hot deck techniques, which guarantee the preservation of the real observed data and avoid the misspecification bias generated by the parametric framework. This is remarkable in the observational studies research context (e.g. for the counterfactual analysis in agricultural economics) where, in order to assess a policy impact, we have to deal with just observed data. We apply the hot deck techniques to integrate FADN (Farm Accountancy Data Network) data and an ad hoc project survey referred to the Emilia-Romagna (Italy) farm population. We also propose a validation strategy in order to assess the matching goodness. Acknowledgement

A socioeconomic impact assessment of three Italian national parks

The expansion of protected areas (PAs) is feared to negatively affect the local economy, as every PA, albeit to different degrees, entails restriction to the economic activities. The literature on the topic has started assessing what is the socioeconomic impact of PAs, mostly focusing on the Global South. The objective of this article is the analysis of the socioeconomic impact of three Italian national parks (NPs), established in the 2000s, using a counterfactual approach based on both the outcome regression diff-in-diff and the doubly robust diff-in-diff combined with different propensity score-based and Mahalanobis distance matching procedures. We find that the three Italian NPs have a robust and statistically significant impact on average income of residents in municipalities hosting them. Conversely, there is weak evidence that population and local establishments are positively affected, and touristic local establishments and employment are negatively affected by the three NPs. All together the results indicate that the three NPs have no negative effect on the socioeconomic dynamics of the territories impacted, although additional investigations are required to shed lights to the impact mechanisms

Farmland abandonment, public goods and the CAP in a marginal area of Italy

Land abandonment is affecting several areas of Europe, and the issue has since some years become a policy objective. The consequences of land abandonment are however difficult to assess as both agriculture and land abandonment are linked to socio-environmental public goods, but the relationship between public good provision and land use, as well as their societal value, are unclear and debated. Policy such as the Common Agricultural Policy affects land abandonment and public good provision in different ways, by providing income support and targeting the provision of environmental public goods.The objective of the paper is to assess the land use, public good levels and welfare deriving from agricultural production and from the provision of three selected PGs, in three alternative scenarios. In a reference scenario land use allocation is driven by the maximization of agricultural income; we then compare these results with a scenario where land use decisions maximize the societal welfare, hence including the value generated by the three, and with a scenario that simulates Measure 13 of the Rural Development Programme (payment for Areas Facing natural or other specific Constraints). The method used is a land allocation model calibrated for the hill and mountain area of the province of Bologna (Italy), in which the public goods societal values are the results of a choice experiments taken in the Emilia-Romagna region. The main results is that the societal optimum is reached through a substantial change in land allocation (e.g. a strong reduction in land abandonment and an increase in forest areas) and in the composition of the welfare (from private agricultural income toward public good benefits) with respect to the private optimum. Moreover, generic income support reduces land abandonment but also total welfare as it has negative effects through the reduction of carbon sequestration and increase in soil erosion. More targeted policies, that more explicitly connect support to public good provision, have better welfare effects

Pseudo-dynamic approach for active thrust of submerged soils

The proper calculation of dynamic thrust is a key issue in the design of rigid retaining walls in seismically active zones. Although the Mononobe–Okabe approach is widely used in practical applications, the pseudo-dynamic approach has been introduced in recent years, and provides a more realistic representation of an earthquake compared to the pseudo-static approach. Whereas studies in the past have focused on dry backfills, to the authors' knowledge there is no specific literature dedicated to pseudo-dynamic analysis for submerged soils; in certain studies dealing with waterfront areas, the pseudo-dynamic analysis – valid for dry soils – has been incorrectly extended to submerged backfills as well. In this paper, a more rational pseudo-dynamic approach is developed for fully submerged soil under the assumption that a restrained or free water condition exists within the backfill. The results obtained demonstrate that the proposed analysis is perfectly consistent with the widely used pseudo-static approach. The analysis is also extended to account for amplification phenomena. Within a range of practical interest of soil and seismic input parameters, the acting point of the seismic active thrust is found to be very close to a height of H/3 from the base of the wall

A European perspective on acceptability of innovative agri-environment-climate contract solutions

The agri-environment-climate measures of the European Union Common Agricultural Policy are incentives aiming to reduce negative environmental impacts and increase positive effects generated from agriculture. Several criticisms have been addressed to their efficiency and effectiveness and thus, the design of innovative contract solutions is currently suggested. Among the novel contractual solutions, there are result-based payments, collective implementation of measures, the engagement of private and business actors in value chains, and new forms of land tenure systems coupled with environmental clauses. Little is known about the factors at interplay influencing farmers’ decision to uptake such contracts. The present paper investigates the acceptability determinants of the above-mentioned novel contractual solutions concerning a sample of nearly 1900 farmers from 10 European Union countries. The analysis is based on a questionnaire built through a common research framework. We apply ordered logistic regressions: both proportional and partial proportional odds models are used. Farmers’ preferences are interpreted by splitting the innovative contractual solutions into 13 individual contractual features which are then modeled in combination with the structural characteristics of the farms and the sociodemographic and behavioral characteristics of the farmers. We estimate farmers’ willingness to enroll in result-based, collective, value-chain, and land tenure contracts and highlight the positive and negative factors potentially influencing farmers’ acceptability of each type of contract

Zuranolone, a positive allosteric modulator of the GABAA receptor and a neuroactive steroid: hypothesized mechanism of action in depression

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