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Using a before-after study design in a stable, largely undisturbed pond habitat and a dataset spanning 33 years, we document and describe the decline of native Sonora mud turtles (Kinosternon sonoriense) after the introduction of non-native pond sliders (Trachemys scripta). The Sonora mud turtle population in Montezuma Well in central Arizona, USA, declined to less than 25% of previous numbers, from 372 ± 64 in 1983 to 80 ± 21 in 2011. We trapped and removed the non-native turtles between 2007 and 2013 and after removal of the non-natives, the Sonora mud turtle population increased to 139 ± 34 in 2015. The native turtles also significantly increased basking activity after removal of the non-natives, paralleling results of small-scale mesocosm studies showing that pond sliders negatively affect basking rates of native turtle species. Reproductive rates of female Sonora mud turtles (numbers of females with eggs) were lower during the period of peak non-native turtle abundance, and increased after removal of the non-native turtles. We hypothesize that the reduction in effective reproductive rate links interference competition (reflected in reduced basking rates) to the long-term decline of the native mud turtles. Results from the undisturbed natural system of Montezuma Well provide new insights on the overall occurrence, magnitude, and mechanisms of negative effects of introduced pond sliders on native turtle species. Sonora mud turtles are very different in their morphology, behavior, and ecology from pond sliders and from native turtles in other studies, suggesting that impacts of non-native pond sliders are more pervasive than previously thought. [ABSTRACT FROM AUTHOR]

We analyze effects of noneconomic damages caps and attorney fee limits (AFLs) on the ability of people injured by negligent physicians to retain qualified lawyers to represent them. We employ survey data from 965 plaintiffs' attorneys who reported likelihoods of accepting hypothetical meritorious cases described by scenarios. We estimate how willingness to accept such cases increases with the expected hourly fees associated with them, and the estimates suggest substantial effects and plausible tradeoffs. We conclude that caps and AFLs make it harder to retain counsel in various circumstances, and we present policy simulations elucidating how several factors combine to determine these effects. [ABSTRACT FROM AUTHOR]

Some states use physicians' histories of medical malpractice payments to try to reduce the incidence of medical malpractice (and for other reasons). At least two types of policies fall into this category: using payments to decide which physicians will be investigated, and possibly sanctioned, by the state medical board; and making information about individual physicians' payment histories available to the public. Previous literature suggests that such policies will not be very effective because the link between medical malpractice and medical malpractice payments appears weak. Unlike previous researchers, we examine this issue directly and quantitatively. To do so, we develop a micro-simulation model of the random processes determining medical outcomes, claiming rates, and payment rates, using information from several strands of literature to calibrate its parameters. To examine sensitivity of our predictions to changes in assumptions, we also consider 14 alternative models. For each of the 15 cases, we simulate data for a population of 100,000 physicians and analyze the simulated data. We find that neither type of policy will substantially reduce the population rate of malpractice and that the policy of publicizing payment histories could, in principle, backfire. [ABSTRACT FROM AUTHOR]

Examines the characterization of ruthenium(Ru)-based metathesis catalysts. Effects of heterocyclic ligand on the catalytic activity; Account on the catalyst involved in promoting ring-closing metathesis; Synthesis of Ru-containing dendrimers; Factors affecting the levels of efficiency observed with Ru-dendrimers.

Focuses on debates over whether to eliminate monk parakeets in the United States. Whether the monk parakeet is the ecological equivalent of the Carolina parakeet; Comparison of the ecology of the two species.

Argues against the claim that the automobile safety legislation in the United States has failed to produce the desired outcome of saving lives. Reasons for the criticisms against the legislation; Negative aspects of using statistical results in the analysis of the policy's effectiveness.

This article presents a commentary on a paper which addressed the issues associated with the construction of posterior probabilities for violation of the independence axiom of expected utility from non-experimental data using seat-belt-usage data. The objective of using non-experimental data to compare different models of decision making is extremely important. The basic empirical approach of the paper is impressive and sound. The number of potential applications of the basic approach may, however, be quite limited. In regard to the seat-belt application, one is left with many plausible interpretations of the basic observation that motivates the analysis. Consider some of them: (a) No individual, in fact, wears a seat belt for the morning commute but not for the evening commute; (b) people are not basing their decisions on any explicit calculations; (c) some people are more fatigued or preoccupied in the evening and simply forget to wear their belts because of this; (d) people maximize expected utility but perceive additional benefits to wearing seat-belts with children in the car, and this is more common during the morning hours; (e) people maximize expected utility but are more fatigued or preoccupied in the afternoon thus raising the cost of seat-belt use.

Comments on the article by Gail Blattenberger and Frank Lad about the application of operational subjective statistical methods to rational expectations in the U.S. Use of subjective predictivism; Joint sequential forecasting of the logarithms of nominal gross national product; Evaluation of predictive distributions and scoring.

Discusses deer hunting, deer managing, controlling and maintaining the deer herd. Our sources of information for these subjects; Author's healthy dose of skepticism; Manipulation of deer numbers; Deer-vehicle accidents; Wildlife managed for hunting; Reasons to extirpate; Whether shooting deer is for their own good; Starvation excuse for hunting; Politically potent; Details.

Investigates the chiral ruthenium catalyst for enantioselective olefin metathesis. Metal complexes of the chiral imidazolinium ligands; Homodimerization of the olefins; Characterization of the chiral complexes.