Do Zoos and Aquariums Promote Attitude Change in Visitors? A Critical Evaluation of the American Zoo and Aquarium Study

Modern-day zoos and aquariums market themselves as places of education and conservation. A recent study conducted by the American Zoo and Aquarium Association (AZA) (Falk et al., 2007) is being widely heralded as the first direct evidence that visits to zoos and aquariums produce long-term positive effects on people’s attitudes toward other animals. In this paper, we address whether this conclusion is warranted by analyzing the study’s methodological soundness. We conclude that Falk et al. (2007) contains at least six major threats to methodological validity that undermine the authors’ conclusions. There remains no compelling evidence for the claim that zoos and aquariums promote attitude change, education, or interest in conservation in visitors, although further investigation of this possibility using methodologically sophisticated designs is warranted

Time trends and persistence in European temperature anomalies.

This paper looks at the level of persistence in the temperature anomalies series of 114 European cities. Once this level of persistence has been identified, the time trend coefficients are estimated and the results indicate that most of the series examined display positive trends, supporting thus climate warming. Moreover, the results obtained confirm the hypothesis that long-memory behaviour cannot be neglected in the study of temperature time series, changing, therefore, the estimated effect of global warming.pre-print825 K

Analyticity and uniform stability in the inverse spectral problem for Dirac operators

We prove that the inverse spectral mapping reconstructing the square integrable potentials on [0,1] of Dirac operators in the AKNS form from their spectral data (two spectra or one spectrum and the corresponding norming constants) is analytic and uniformly stable in a certain sense.Comment: 19 page

Nb3AlNb_{3}Al prototype conductor for the transmission line magnet

The Very Large Hadron Collider (VLHC), under consideration for construction at Fermilab in the next 1-2 decades, is a 100 TeV cm pp collider. A major cost driver is the magnet. R&D is underway on several possible magnet designs. A low-field (2T) superferric magnet, sometimes called a transmission line magnet, may be the most cost- effective route to the VLHC. Although NbTi is now the cheapest superconductor measured in cost/kA-meter, Nb/sub 3/Al has the potential advantage that it remains superconducting at higher temperature. It may be particularly suited to the single "turn" and long straight lengths of the transmission line design. The combination of the simple magnet design and the higher strain tolerance than e.g. Nb/sub 3/Sn allows a simple process of cable fabrication, reaction, and magnet assembly. This higher strain tolerance is an advantage for splicing in the field. Sumitomo Electric Industries is producing an Nb/sub 3/Al conductor for the Fermilab low-field magnet program. (9 refs)

Emergent complex neural dynamics

A large repertoire of spatiotemporal activity patterns in the brain is the basis for adaptive behaviour. Understanding the mechanism by which the brain's hundred billion neurons and hundred trillion synapses manage to produce such a range of cortical configurations in a flexible manner remains a fundamental problem in neuroscience. One plausible solution is the involvement of universal mechanisms of emergent complex phenomena evident in dynamical systems poised near a critical point of a second-order phase transition. We review recent theoretical and empirical results supporting the notion that the brain is naturally poised near criticality, as well as its implications for better understanding of the brain

The Effects of Home Computers on Educational Outcomes: Evidence from a Field Experiment with Schoolchildren

Are home computers are an important input in the educational production function? To address this question, we conduct a field experiment involving the provision of free computers to schoolchildren for home use. Low-income children attending middle and high schools in 15 schools in California were randomly selected to receive free computers and followed over the school year. The results indicate that the experiment substantially increased computer ownership and total computer use among the schoolchildren with no substitution away from use at school or other locations outside the home. We find no evidence that the home computers improved educational outcomes for the treatment group. From detailed administrative data provided by the schools and a follow-up survey, we find no evidence of positive effects on a comprehensive set of outcomes such as grades, test scores, credits, attendance, school enrollment, computer skills, and college aspirations. The estimates also do not indicate that the effects of home computers on educational outcomes are instead negative. Our estimates are precise enough to rule out even modestly-sized positive or negative impacts. The lack of a positive net effect on educational outcomes may be due to displacement from non-educational uses such as for games, social networking, and entertainment. We find evidence that total hours of computer use for games and social networking increases substantially with having a home computer, and increases more than total hours of computer use for schoolwork