Creation and dynamics of two-dimensional skyrmions in antiferromagnetic spin-1 Bose-Einstein condensates

We numerically simulate the creation process of two-dimensional skyrmionic excitations in antiferromagnetic spin-1 Bose--Einstein condensates by solving the full three-dimensional dynamics of the system from the Gross--Pitaevskii equation. Our simulations reproduce quantitatively the experimental results of [Choi et al., Phys. Rev. Lett. 108, 035301 (2012)] without any fitting parameters. Furthermore, we examine the stability of the skyrmion by computing the temporal evolution of the condensate in a harmonic potential. The presence of both the quadratic Zeeman effect and dissipation in the simulations is vital for reproducing the experimentally observed decay time.Comment: 6 pages, 7 figure

Counterfactual approach for assessing agri-environmental policy: The case of the Finnish water protection policy

This paper applies counterfactual approach to assess the impacts of agri-environmental programs. Counterfactual analysis evaluates policies answering questions: what would have happened if...? We develop a theoretical framework for counterfactual analysis based on the inter-linkages between the behaviour of agents and the response of environmental systems to the economic decisions. We apply our model to assess the performance of the Finnish Agri- Environmental Programme to reduce agricultural nutrient runoff to the Baltic Sea. Counterfactual analysis allows us to determine both the unit effectiveness of the measures included in the Programme and its preventive impact. We demonstrate that the Finnish Agri- Environmental Programme does not achieve its goals, because it fails to anticipate farmers’ responses to incentives created by the Common Agricultural Policy and the Agri-Environmental Programme itself. The social cost-benefit analysis of the Program shows negative net benefits: benefits from reduced nutrient loading are much lower than support payments.Environmental policy evaluation, counterfactual analysis, nutrient runoff, the Baltic Sea, Agricultural and Food Policy, Q5, H23, H43,

Multifunctional Agriculture: The Effect of Non-Public Goods on Socially Optimal Policies

We develop a general framework for multifunctional agriculture, which includes not only public goods but also rural viability as a non-public good item. We contribute to the literature in two ways. First, we demonstrate how the broader definition of multifunctional agriculture differs from the agri-environmental multifunctionality, and how agri-environmental policy should be reformed to include these aspects. We show that rural viability entails adjusting fertilizer tax and buffer strip subsidy below their first-best Pigouvian levels to reflect the direct and indirect employment effects of agricultural production. Moreover, we show that when non-agricultural land use is present, an additional, non-agricultural instrument is needed to adjust the amount of land allocated to agriculture to its optimal level. In a parametric model calibrated to Finnish agricultural conditions and Finnish valuation of agri-environmental amenities and rural viability, we assess how the socially optimal provision of non-public good multifunctionality relates the socially optimal agri-environmental multifunctionality.biodiversity, employment, nutrient runoffs, rural viability, Labor and Human Capital, Resource /Energy Economics and Policy,

Multifunctionality: Environment versus Rural Viability in Social Optima

We examine policy implications of including rural viability to the notion of multifunctional agriculture. We assume that rural viability refers predominantly to the number of people living in rural areas to keep the infrastructure and living conditions at good state for a good life. The economic core of viability is employment in agriculture and agriculture serving sectors. Viability benefits are modelled with the help of a viability valuation function. We demonstrate that rural viability entails adjusting fertilizer tax and buffer strip subsidy below their environmental first-best Pigouvian levels to reflect the direct and indirect employment effects of agricultural production. Moreover, when non-agricultural land use is present, an additional, non-agricultural instrument is needed to adjust the amount of land allocated to agriculture to its socially optimal level. Thus, inclusion of rural viability creates distortions in multifunctional policies. Theoretical results are illustrated with Finnish data to examine how the inclusion of rural viability to multifunctionality relates to the true socially optimal agri-environmental multifunctionality. We also assess welfare loss from promoting rural viability in the case where there is no base on viability benefits.biodiversity, employment, nutrient runoff, rural viability, Agribusiness, Agricultural and Food Policy, Community/Rural/Urban Development, Environmental Economics and Policy, Political Economy, Production Economics, Productivity Analysis,

Impacts of Agri-Environmental Policies on Land Allocation and Land Prices

We develop a Ricardian framework with heterogeneous land quality to analyse the effects of agricultural and agri-environmental support policies on land allocation decisions and land prices. Four agri-environmental policy instruments are considered: a uniform area payment, a quality-dependent area payment, a mandatory buffer strip policy and a voluntary buffer strip payment. We also analyse how general tax and monetary policies may affect agricultural land prices. The theoretical framework is illustrated by an empirical model applied to Finnish agriculture. The empirical model shows that macroeconomic factors, such as general tax and monetary policies, may exert a greater impact on land prices than some minor fine-tuning in agrienvironmental policies.agri-environmental policy, acreage subsidy, land price, Q11, Q18, Environmental Economics and Policy, Land Economics/Use,

Agri-environmental program compliance under heterogeneous conditions

Heterogeneity of agricultural landscapes may necessitate the use of spatially targeted instrument combinations to implement the social optimum. But compliance with these policies may require costly enforcement. This paper examines the design of agri-environmental policies featuring two of the most commonly used instruments, reductions in fertilizer application rates and installation of riparian buffers. While compliance with buffer strip requirements is verifiable at negligible cost, fertilizer application is only verifiable through costly monitoring. We derive optimal subsidies for fertilizer reduction and buffer strip set-asides and enforcement strategies for the cases of low and excessive monitoring costs. An empirical simulation model suggests that enforceable policies can come close to replicating socially optimal crop production, nitrogen runoff, and overall welfare without requiring increases in overall subsidy expenditures, at least under conditions characteristic of Scandinavia.nutrient runoff, monitoring, enforcement, Environmental Economics and Policy,

Agri-Environmental Program Compliance in a Heterogeneous Landscape

Heterogeneity of agricultural landscapes may necessitate the use of spatially targeted instrument combinations to implement the social optimum. But compliance with these policies may require costly enforcement. This paper examines the design of agri-environmental policies featuring two of the most commonly used instruments, reductions in fertilizer application rates and installation of riparian buffers. While compliance with buffer strip requirements is verifiable at negligible cost, fertilizer application is only verifiable through costly monitoring. We derive optimal subsidies for fertilizer reduction and buffer strip set-asides and enforcement strategies for the cases of low and excessive monitoring costs. An empirical simulation model suggests that enforceable policies can come close to replicating socially optimal crop production, nitrogen runoff, and overall welfare without requiring increases in overall subsidy expenditures, at least under conditions characteristic of Scandinavia. Sensitivity analysis suggests that these conclusions may carry over to areas with higher overall land quality as well.nutrient runoff, monitoring, enforcement, Agricultural and Food Policy, Environmental Economics and Policy, Q15, Q18, H23,

To Till or Not to Till? Social Profitability of No-Till Technology

We study from economic and environmental angles under what conditions no-till technology is socially optimal. We demonstrate theoretically that if yield under no-till is equal to or greater than under conventional technology, its adoption is socially optimal provided that herbicide runoff damages under both technologies are close enough. Finnish data shows, however, that only in one case out of three no-till provides higher social returns. In terms of nutrient runoffs no-till performs better than conventional technology. No-till reduces surface runoffs of nitrogen by 58%, and surface runoffs of particulate phosphorus by 70% relative to conventional technology, but causes more than three times higher dissolved phosphorus surface runoffs. The amount of total phosphorus surface runoff is, however, lower under no-till. No-till produces higher total herbicide runoff because of higher use of herbicides to control perennial weeds.nutrient runoffs, herbicide runoffs, buffer strips, agri-environmental policy, Crop Production/Industries, Q16, Q18, H23,

The Impacts of Alternative Policy Scenarios on Multifunctionality

This paper provides first results of the sector model approach to analyze the effects of alternative policy scenarios on the multifunctional role of Finnish agriculture. In terms of environmental non-commodity outputs we focus on nutrient runoffs, landscape diversity and biodiversity. As regards to socio-economic outputs our focus is on direct and indirect agricultural labour force. The results suggest that while partial de-coupling agricultural supports from production is not likely to result in any drastic decline of agricultural production the amount of green fallow will increase considerably. As a result, the agricultural land will become biologically richer. The agricultural labour force is likely to decrease substantially irrespective of agricultural policy.agricultural policy, multifunctionality, sector model, Agricultural and Food Policy, Q18, Q21,

Structural analysis of the evolution of steroid specificity in the mineralocorticoid and glucocorticoid receptors

BACKGROUND: The glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) evolved from a common ancestor. Still not completely understood is how specificity for glucocorticoids (e.g. cortisol) and mineralocorticoids (e.g. aldosterone) evolved in these receptors. RESULTS: Our analysis of several vertebrate GRs and MRs in the context of 3D structures of human GR and MR indicates that with the exception of skate GR, a cartilaginous fish, there is a deletion in all GRs, at the position corresponding to Ser-949 in human MR. This deletion occurs in a loop before helix 12, which contains the activation function 2 (AF2) domain, which binds coactivator proteins and influences transcriptional activity of steroids. Unexpectedly, we find that His-950 in human MR, which is conserved in the MR in chimpanzee, orangutan and macaque, is glutamine in all teleost and land vertebrate MRs, including New World monkeys and prosimians. CONCLUSION: Evolution of differences in the responses of the GR and MR to corticosteroids involved deletion in the GR of a residue corresponding to Ser-949 in human MR. A mutation corresponding to His-950 in human MR may have been important in physiological changes associated with emergence of Old World monkeys from prosimians