Conservation Contracts and Political Regimes

Motivated by tropical deforestation, we analyze (i) a novel theory of resource extraction, (ii) the optimal conservation contract, (iii) when the donor prefers contracting with central rather than local governments, and (iv) how the donor’s presence may induce institutional change. Deforestation can be legal or illegal in the model: each district decides how much to protect and how much to extract for sale on a common market. If districts are strong, in that they find protection inexpensive, extraction is sales-driven and districts bene.t if neighbors conserve. If districts are weak, they lose when neighbors conserve since the smaller supply increases the price and the pressure on the resource, and thus also the cost of protection. Consequently, decentralizing authority increases conservation if and only if districts are weak. Contracting with the central authority is socially optimal, but, on the one hand, the donor benefits from contracting with districts if they are weak; on the other hand, districts prefer to decentralize if they are strong. The presence of the donor may lead to a regime change that increases extraction by more than it is reduced by the contract itself

Network Economics and the Environment: Insights and Perspectives

Local interactions and network structures appear to be a prominent feature of many environmental problems. This paper discusses a wide range of issues and potential areas of application, including the role of relational networks in the pattern of adoption of green technologies, common pool resource problems characterized by a multiplicity of sources, the role of social networks in multi-level environmental governance, infrastructural networks in the access to and use of natural resources such as oil and natural gas, the use of networks to describe the internal structure of inter-country relations in international agreements, and the formation of bilateral "links" in the process of building up an environmental coalition. For each of these areas, we examine why and how network economics would be an effective conceptual and analytical tool, and discuss the main insights that we can foresee

Set up of a serum-free culture system for bovine embryos: embryo development and quality before and after transient transfer

It is well known that serum in culture medium negatively affects blastocyst quality. The objective of this work was to develop and test a serum-free culture medium which could improve embryo quality, measured by the resistance to freezing, lipid and glutathione content of the resulting blastocysts, as well as the ability of the blastocysts to elongate after transient transfer to recipient cows. In a first experiment we showed that adding a mixture of insulin, transferrin and selenium to serum-free Synthetic Oviduct Fluid medium (SOF–ITS) improved embryo development and quality. In the second experiment, the addition of BSA to SOF–ITS further improved blastocyst development. Moreover, a reduction in lipid content of morulae was observed in SOF–ITS–BSA by comparison with morulae cultured with serum (SOF–FCS). The resistance to freezing measured by hatching rates 24 h postthawing was also improved for blastocysts with a diameter between 160 and 180 mm cultured in SOF–ITS–BSA by comparison to those produced with serum. In order to evaluate the redox potential of the embryos, reduced glutathione content (GSH) was evaluated both before and after cryopreservation. A significant decrease in glutathione was observed after freezing, whatever the culture medium, but no difference was observed between culture conditions. Transient transfers were performed and elongated D- 13 embryos were recovered. Elongation was more pronounced and the embryonic disk more often visible in embryos cultured in SOF–ITS–BSA than in embryos cultured with FCS. In conclusion, the serum-free system we developed to produce in vitro bovine embryos meets the developmental and qualitative requirements for a large-scale use

Comparative study of the body surface electrocardiogram in double-muscled and conventional calves.

The purpose of this work was to study electrocardiographic features of double-muscled beef cattle. Electrocardiograms were recorded on one to six occasions from each of a group of 18 conventional calves of the Friesian breed and 29 double-muscled calves of the Belgian White and Blue breed. Ages of the calves at the times of examination ranged from eight to 348 days. The Holmes semi-orthogonal lead system was used. The waves and interval durations and the tridimensional P, QRS, and T modal vector orientation and amplitude were calculated. The magnitude of the cardiac vectors was significantly lower and the ventricular waves and QT interval duration significantly shorter in the double-muscled than in the conventional calves. The P modal vector pointed significantly less downwards and the QRS modal vector pointed significantly more forwards and less up- and rightwards in the Belgian White and Blue, than in the Friesian group. Most of the observed differences might be a consequence of the bodily, and more specifically the thoracic, conformation of the former calves. However, the lower cardiac vector magnitude and shorter wave and interval durations might also reflect lower cardiac mass in the double-muscled subjects