Colladay and Kostelecký have proposed a framework for studying Lorentz and CPT violation in a natural extension of the standard model. Although numerous bounds exist on the Lorentz and CPT violating parameters in the gauge boson and fermion sectors, there are no published bounds on the parameters in the Higgs sector. We determine these bounds. The bounds on the CPT-even asymmetric coefficients arise from the one-loop contributions to the photon propagator, those from the CPT-even symmetric coefficients arise from the equivalent c coefficients in the fermion sector, and those from the CPT-odd coefficient arise from bounds on the vacuum expectation value of the Z boson.

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The ranking of an academic journal is important to authors, universities, journal publishers, and research funders. Rankings are gaining prominence as countries adopt regular research assessment exercises that especially reward publication in high‐impact journals. Yet even within a rankings‐oriented discipline like economics there is no agreement on how aggressively lower‐ranked journals are down‐weighted and in how wide is the universe of journals considered. Moreover, since it is typically less costly for authors to cite superfluous references, whether of their own volition or prompted by editors, than it is to ignore relevant ones, rankings based on citations may be easily manipulated. In contrast, when the merits of publication in one journal or another are debated during hiring, promotion, and salary decisions, the evaluators are choosing over actions with costly consequences. We therefore look to the academic labor market, using data on economists in the University of California system to relate their lifetime publications in 700 different academic journals to salary. We test amongst various sets of journal rankings, and publication discount rates, to see which are most congruent with the returns implied by the academic labor market. (JEL A14, I23, J44)

Zeolite cracking catalysts used by petroleum refineries were analyzed for 38 elements. Concentration patterns of rare earth elements (REEs) in 10 zeolite catalysts show an enhancement of light REEs relative to the crustal abundance pattern, resembling those measured in refineries emissions. Release of zeolite catalyst material from fluidized catalytic crackers and incorporation of zeolite catalysts into refined oil provide new atmospheric elemental signatures for tracing emissions from refineries and oil-fired power plants, respectively. Though both have enhanced La/REE ratios, emissions from these two sources can be distinguished by their La/V ratios. Three-way catalytic converters of newer automobiles contain REEs and may, thus, be a significant source in some cities.

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This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

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Very light pseudoscalars can arise from the symmetry-breaking sector in many extensions of the Standard Model. If their mass is below 200 MeV, they can be long-lived and have interesting phenomenology. We discuss the experimental constraints on several models with light pseudoscalars, including one in which the pseudoscalar is naturally fermiophobic. Taking into account the stringent bounds from rare K and B decays, we find allowed parameter space in each model that may be accessible in direct production experiments. In particular, we study the photoproduction of light pseudoscalars at Jefferson Lab and conclude that a beam dump experiment could explore some of the allowed parameter space of these models.