Effects of moderate abundance changes on the atmospheric structure and colours of Mira variables (Research Note)

Aims. We study the effects of moderate deviations from solar abundances upon the atmospheric structure and colours of typical Mira variables. Methods. We present two model series of dynamical opacity-sampling models of Mira variables which have (1) 1 solar metallicity 3 and (2) "mild" S-type C/O abundance ratio ([C/O]=0.9) with typical Zr enhancement (solar +1.0). These series are compared to a previously studied solar-abundance series which has similar fundamental parameters (mass, luminosity, period, radius) that are close to those of o Cet. Results. Both series show noticeable effects of abundance upon stratifications and infrared colours but cycle-to-cycle differences mask these effects at most pulsation phases, with the exception of a narrow-water-filter colour near minimum phase.Comment: 4 pages, 3 figures, accepted for A&

Paper Session I-B - Space Education, Why Space Intimidates Teachers

Post World War II saw the advent of social changes of major proportions. Television became ubiquitous, with violence a major feature; for young people, the daily dose of tube time and video games has largely supplanted reading and homework- Permissiveness has replaced discipline. Violent crime has risen 560 per cent since I960, and has invaded our schools. SAT scores in high schools have dropped 75 points in three decades. William Bennett, former Secretary of Education, calls this cultural rot. In this setting experimental educational techniques were implemented for the grand purpose of improving U.S. competitiveness in future generations. Sight reading replaced phonics, and the new math replaced the traditional course of study. These methods, and others such as open classrooms designed to promote freedom of movement and creativity, and remedial education tor students who underachieve, have resulted in a society plagued by illiteracy

COVID-19 and the difficulty of inferring epidemiological parameters from clinical data

Knowing the infection fatality ratio (IFR) is of crucial importance for evidence-based epidemic management: for immediate planning; for balancing the life years saved against the life years lost due to the consequences of management; and for evaluating the ethical issues associated with the tacit willingness to pay substantially more for life years lost to the epidemic, than for those to other diseases. Against this background Verity et al. (2020, Lancet Infections Diseases) have rapidly assembled case data and used statistical modelling to infer the IFR for COVID-19. We have attempted an in-depth statistical review of their approach, to identify to what extent the data are sufficiently informative about the IFR to play a greater role than the modelling assumptions, and have tried to identify those assumptions that appear to play a key role. Given the difficulties with other data sources, we provide a crude alternative analysis based on the Diamond Princess Cruise ship data and case data from China, and argue that, given the data problems, modelling of clinical data to obtain the IFR can only be a stop-gap measure. What is needed is near direct measurement of epidemic size by PCR and/or antibody testing of random samples of the at risk population.Comment: Version accepted by the Lancet Infectious Diseases. See previous version for less terse presentatio

Ultra-Low Amplitude Cepheids in the Large Magellanic Cloud

The MACHO variables of LMC Field 77 that lie in the vicinity of the Cepheid instability strip are reexamined. Among the 144 variables that we identify as Cepheids we find 14 that have Fourier amplitudes <0.05 mag in the MACHO red band, of which 7 have an amplitude <0.006 mag : we dub the latter group of stars ultra-low amplitude (ULA) Cepheids. The variability of these objects is verified by a comparison of the MACHO red with the MACHO blue lightcurves and with those of the corresponding OGLE LMC stars. The occurrence of ULA Cepheids is in agreement with theory. We have also discovered 2 low amplitude variables whose periods are about a factor of 5--6 smaller than those of F Cepheids of equal apparent magnitude. We suggest that these objects are Cepheids undergoing pulsations in a surface mode and that they belong to a novel class of Strange Cepheids (or Surface Mode Cepheids) whose existence was predicted by Buchler et al. (1997).Comment: 4 pages, 5 figures, slightly revised, to appear in ApJ Letter

Combining international cap-and-trade with national carbon taxes

This paper examines the effects of combining an international cap-and-trade scheme with national carbon taxes. We consider a two-country stochastic partial equilibrium model with log-normally distributed uncertainty. The situation is analogous to the situation where European countries impose national carbon taxes in addition to the EU emissions trading. The allowance price in the joint cap-and-trade scheme depends on the tax rate, the relative size of countries and abatement options, the magnitude of uncertainty, and correlation of abatement costs. In most cases, the additional tax will not lead to additional production of the public good beyond the fixed targets. The additional tax results in higher costs of abatement to the country introducing the additional tax, and higher costs overall

Mental Health Malingering and the Fraudulent Motor Insurance Claimant

Malingering is the intentional production of false or grossly exaggerated symptoms in order to obtain an advantage. Although it has been estimated that over 800,000 claims for personal injury in Road Traffic Accidents (RTA) were filed in the UK in 2012, no approximation exists forhow many involved malingering. This study attempts to understand what influences a psychiatrist to conclude that a claimant’s symptoms are not caused by an RTA and thus suggests the claimant is malingering. This article describes a study of Personality Assessment Inventory scores alongside collateral forms of evidence for 100 RTA claimants; all individuals seeking compensation for damages to their mental health. The results suggest that up to 40% of these claims could be cate-gorised as not being the result of the RTA. Significant differences emerged between those claimants diagnosed as having a mental disorder as a result of the RTA and those claimants who were classified as not having a mental disorder as a result of the RTA in regards to: employment status, level of injuries and scores on the paranoia scales of the PAI.The study emphasises how the assessment process is idiosyncratic and in need of further researc

Linking price and quantity pollution controls under uncertainty

This paper examines the linking of price-based and quantity-based provision of a public good by two parties in the example of pollution control under a global quantity constraint, using a stochastic partial-equilibrium model. One country chooses a price-based instrument (tax) and trades with another that lets its emissions price adjust. The expected cost for the price-setting country and the combined expected cost is higher than if both countries choose a quantity-based instrument, and the country with the quantity instrument stands to benefit in terms of expected net costs. The effect increases when the relative size of the country with the price-based constraint increases; and increases with respect to the degree of correlation in ex-ante uncertain abatement costs. While the quantity-setting country benefits from lower expected costs in most circumstances, the variance in cost can be much higher if its costs are correlated with the price-setting country. The optimal ex-ante tax rate differs from that under quantity-quantity linking. These results have important implications for instrument choice for the regulation of greenhouse gases and other pollutants and for the design of international agreements when there are domestic preferences for price regulation. The model is applicable to situations involving the provision of a fixed quantity of a public good beyond pollution control