Perceptions of personal risk in tourists’ destination choices: nature tours in Mexico

Terrorism, pandemic diseases, and other threatening events have recently heightened the sense of personal risk for tourists considering international travel. This article addresses the paucity of research assessing perceptions of risk both before and during travel to risky destinations. Tourists on two nature tours in Mexico were interviewed and observed while engaged in the travel. Many types of specific perceived risks were uncovered, including insect-borne disease, traffic accidents, financial losses, and unattained goals. Some correlates of perceived risk were tour company reputation, stage of family life cycle, age, and motivation. Based on the types of perceived risk and the factors, five propositions are discussed. One unexpected proposition addresses the role of age and states that as the perceived years of physical ability to travel decreases, the tolerance for safety risk increases. Another proposes that eco-tourists with intense, destination- specific motivations are more tolerant of travel risk than those with casual and/or social motivations. The article concludes with suggestions for tour industry managers and directions for future research

The Private Provision of Public Goods: An Analysis of Homes on Golf Courses

This paper examines the joint production of golf and real estate development. The empirical results of this analysis show that, over time, golf courses are being constructed less for recreational golf and more for contractual assurance of green open space for homes. We believe that this fundamentally provides some evidence that the demand for environmental quality is growing and that markets are increasingly able to find creative contracting mechanisms to satisfy demands for public goods

GMP design of a single-use integrated continuous bio manufacturing system

This presentation will show design work by Pfizer and Boehringer Ingelheim on a single-use integrated continuous system for GMP Biomanufacturing including consideration of scale, facility-fit, automation, single-use devices, hardware, and process control and monitoring. The scale of the system needs to be appropriate for the expected quantities of drug substance needed and needs to fit within the constraints of the GMP facility, including physical size and interaction with other facility systems. The system automation needs to control and monitor the entire process, since the upstream and downstream are integrated and the downstream operates semi-continuously. This presentation will discuss the challenges of designing an automation scheme capable of controlling an integrated upstream and downstream process along with the unique features that proved enabling to the integrated system. The single use devices and instruments in the system, including those made with additive manufacturing, are the process contact surfaces, so they need to be compatible with all the process fluids, perform consistently over process cycling and be constructed with sanitary design appropriate for GMP biomanufacturing. The system hardware provides the interface between the automation and the single-use devices controlling operations and the single-use instruments monitoring in-line process data. The design also needs to consider on-line instrument needs and off-line sampling analysis for a continuous flowing process stream

The Sex Ratio and the Out-of-Wedlock Birth Rate in the United States during World War II

This paper provides a theoretical economic framework to study the effects of changes in the sex ratio on the out-of-wedlock birth rate in the United States. We model the demanders and suppliers of sexual relations as potential mates and the relative “price” of human sexual relations as the promises implicit within a traditional marriage (marriage, fidelity, wealth transfers, child support, etc.). We examine an instrument for the implicit “price” of sexual relations, namely the out-of-wedlock birth rate. We show that the reduction in the number of available sex partners for women during World War II decreased the “price”—in terms of marriage—that remaining men had to pay for sex. One result of this lower “price” is an increase in the number of children born out-of-wedlock during the war. According to our regression results, a reduction in the sex ratio of 10 males per 100 females in the U.S. population during World War II increased the out-of wedlock birth rate by six to ten percent

Analysis of substrate specificity of cytochrome P450 monooxygenases involved in trichothecene toxin biosynthesis

[EN]Trichothecenes are a structurally diverse family of toxic secondary metabolites produced by certain species of multiple fungal genera. All trichothecene analogs share a core 12,13-epoxytrichothec-9-ene (EPT) structure but differ in presence, absence and types of substituents attached to various positions of EPT. Formation of some of the structural diversity begins early in the biosynthetic pathway such that some producing species have few trichothecene biosynthetic intermediates in common. Cytochrome P450 monooxygenases (P450s) play critical roles in formation of trichothecene structural diversity. Within some species, relaxed substrate specificities of P450s allow individual orthologs of the enzymes to modify multiple trichothecene biosynthetic intermediates. It is not clear, however, whether the relaxed specificity extends to biosynthetic intermediates that are not produced by the species in which the orthologs originate. To address this knowledge gap, we used a mutant complementation-heterologous expression analysis to assess whether orthologs of three trichothecene biosynthetic P450s (TRI11, TRI13 and TRI22) from Fusarium sporotrichioides, Trichoderma arundinaceum, and Paramyrothecium roridum can modify trichothecene biosynthetic intermediates that they do not encounter in the organism in which they originated. The results indicate that TRI13 and TRI22 could not modify the intermediates that they do not normally encounter, whereas TRI11 could modify an intermediate that it does not normally encounter. These findings indicate that substrate promiscuity varies among trichothecene biosynthetic P450s. One structural feature that likely impacts the ability of the P450s to use biosynthetic intermediates as substrates is the presence and absence of an oxygen atom attached to carbon atom 3 of EPT.SIOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature.Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL

Superhumps in Cataclysmic Binaries. XXV. q_crit, epsilon(q), and Mass-Radius

We report on successes and failures in searching for positive superhumps in cataclysmic variables, and show the superhumping fraction as a function of orbital period. Basically, all short-period systems do, all long-period systems don't, and a 50% success rate is found at P_orb=3.1+-0.2 hr. We can use this to measure the critical mass ratio for the creation of superhumps. With a mass-radius relation appropriate for cataclysmic variables, and an assumed mean white-dwarf mass of 0.75 M_sol, we find a mass ratio q_crit=0.35+-0.02. We also report superhump studies of several stars of independently known mass ratio: OU Virginis, XZ Eridani, UU Aquarii, and KV UMa (= XTE J1118+480). The latter two are of special interest, because they represent the most extreme mass ratios for which accurate superhump measurements have been made. We use these to improve the epsilon(q) calibration, by which we can infer the elusive q from the easy-to-measure epsilon (the fractional period excess of P_superhump over P_orb). This relation allows mass and radius estimates for the secondary star in any CV showing superhumps. The consequent mass-radius law shows an apparent discontinuity in radius near 0.2 M_sol, as predicted by the disrupted magnetic braking model for the 2.1-2.7 hour period gap. This is effectively the "empirical main sequence" for CV secondaries.Comment: PDF, 45 pages, 9 tables, 12 figures; accepted, in press, to appear November 2005, PASP; more info at http://cba.phys.columbia.edu