TRAVEL COST METHODS FOR ESTIMATING THE RECREATIONAL USE BENEFITS OF ARTIFICIAL MARINE HABITAT

The growing popularity of marine recreational fishing has created considerable interest in artificial marine habitat development to maintain and enhance coastal fishery stocks. This paper provides a comparative evaluation of travel cost methods to estimate recreational use benefits for new habitat site planning. Theoretical concerns about price and quality effects of substitute sites, corner solutions in site choice, and econometric estimation are considered. Results from a case study indicate that benefit estimates are influenced by the way these concerns are addressed, but relatively simple single site models can provide defensible estimates. Practical limitations on data collection and model estimation are also considered.Resource /Energy Economics and Policy,

SITE CHARACTERISTICS AND REVEALED PREFERENCES FOR OUTDOOR RECREATION

Resource /Energy Economics and Policy,

A Nested Demand Shares Model of Artificial Marine Habitat Choice by Sport Anglers

There is growing public interest in the development of artificial habitats to enhance and diversify coastal marine resources for recreational and commercial uses. In this article, a hierarchical discrete choice model of recreational demand for artificial habitat is presented using a nested multinomial logit analysis of artificial and natural habitat site choice by sport anglers. The model can be used to evaluate the effects of site characteristics and socioeconomic attributes of individual sport anglers on the share allocation of marine fishing trips and to estimate the economic benefits of new artificial habitat. An empirical application using survey data from sport anglers in southeast Florida is reported. The model parameters are used to estimate the expected use benefits and distributional implications of alternative new artificial habitat sites. Extensions and limitations of the model for artificial habitat planning are considered.Environmental Economics and Policy, Research Methods/ Statistical Methods, Resource /Energy Economics and Policy,

Adhesive factor/rabbit 2, a new fimbrial adhesin and a virulence factor from Escherichia coli O103, a serogroup enteropathogenic for rabbits

Enteropathogenic Escherichia coli-like E. coli strains belonging to serovar O103:K-:H2 and rhamnose-negative biotypes are highly pathogenic diarrhea-inducing strains for weaned European rabbits. We describe here the cloning and sequencing of the major subunit gene of a new fimbrial adhesin, adhesive factor/rabbit 2 (AF/R2), which confers on these strains the ability to attach to rabbit enterocytes and to HeLa cells in a diffuse manner and which is associated with in vivo virulence. The chromosomal operon that encodes functional AF/R2 has been cloned from strain B10. The major subunit gene afr2G, as well as an adjacent open reading frame, afr2H, has been sequenced. The Afr2G protein shows homologies with FaeG and ClpG, which are the respective major subunits of fimbrial adhesin K88 (F4) and afimbrial adhesin CS31A. Plasmid carrying the operon transcomplements an AF/R2-negative TnphoA mutant for its ability to express AF/R2. As a whole, AF/R2 is a new member of the E. coli K88 adhesin family which is associated with virulence and which may serve in the design of vaccines

Is Investment in Environmental Quality a Solution to Recessions? Studying the Welfare Effects of Green Animal Spirits

Assume that 'green accounting' has been adopted and implemented, does an investment in environmental quality play a role similar to the investment in capital in towing the economy out of a recession? To answer the question, we integrate 'green accounting' into a stochastic dynamic general equilibrium model to study the short-run consequences of investment in environmental quality and hereby addressing if there is an incentive-based fiscal environmental solution to recessions. Surprisingly and counter intuitive, we found that reducing the rate at which humans consume the environment renders a fiscal policy - that engage in environmental investment - less effective in providing a thrust out of a recession. Conditional on the proposed model and the calibrated parameters, we conclude that an increase of one percent in environmental investment will crowd out real quarterly consumption in a range from $102.74 billions to$ 171.11 billions, on average, in every quarter for seven years following the investment (measured in chained 2000 dollars). Therefore, we argue that investment in environmental quality is not a solution to recessions. This result is a striking contrast to the conclusion reached in Weitzman and Löfgren (1997, Journal of Environmental Economics and Management, 32 (2), 139-153).Environmental Quality, Green Accounting, Stochastic Dynamic General Equilibrium models

Altération et bifurcation : l’écho est-il neutre ?

L’écho ne se contente pas de reproduire ce qu’il entend comme le souligne la tradition latine. Figure d’Écho, l’écho fait tout ce qu’il peut pour refuser la transparence et la neutralité. Il se venge de la malédiction qu’il porte en altérant tout ce qu’il touche. Sa vengeance est l’expression de son existence. Mais, au-delà de l’écho, c’est toute la question de ces expressions et formes qui vivent en retrait et en attente qui est posée ; la question du suiveur : « qui me précède ? » ; la question de l’ombre : « suis-je une ressemblance ? » ; la question du miroir : « quelle image dois-je renvoyer ? ». La figure de l’écho offre ainsi l’occasion de s’interroger sur la guerre que se livrent l’original et la copie tout en se demandant si l’existence d’un énoncé sans origine est envisageable. À cette question, l’écho répond par la seule arme en sa possession : l’altération. C’est toute la question de la neutralité de l’écho que nous poserons en réfléchissant sur l’altération que la voix d’Écho profère.Far from reproducing what it hears, as the Latin tradition would have it, the echo resists transparency and neutrality. It avenges itself for the curse it carries by distorting everything it touches. Its revenge is the expression of its existence. However, the main concern here has to do with the expressions and forms that live in withdrawal and on standby; the question of the follower: “who precedes me ?”, the question of the shade: “am I a resemblance?”, the question of the mirror: “what image should I return?”... The echo thus offers the opportunity to wonder about the war between the original and the copy, while wondering if the existence of a statement without origin is possible. The echo answers this question with the only weapon in its possession: distortion. I will examine the question of the neutrality of the echo while reflecting on the distortion made by the voice of Echo

Perpetuation of Leishmania: some novel insight into elegant developmental programs

Leishmania spp. are polarized single-celled eukaryotic parasites, the perpetuation of which relies on two other organisms they “use” as hosts. One of the Leishmania host organisms is a blood-feeding female sand fly, the second host being a mammal that acts as a blood source for the female sand fly. Leishmania-hosting sand flies transmit the metacyclic promastigote developmental stage to the mammal skin. While many mammals are known to act as sand fly blood sources, only some of these mammals are/will be “used” as Leishmania hosts. This host status means that skin as well as skin-distant tissues and cell lineages (mononuclear phagocytes and fibroblasts) of these mammals are rapidly and continuously remodelled as niches where Leishmania will deploy its developmental programs: it is noteworthy that without the deployment of the developmental program underlying Leishmania transmission from the mammal to the blood-searching and blood-feeding sand flies, the perpetuation of Leishmania will be suspended. While post genomic approaches are providing insight about some features of Leishmania major, Leishmania infantum/chagasi and Leishmania braziliensis, such approaches are not yet available for the natural hosts (wild rodents, wild sand flies) these Leishmania species “use” as hosts