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Johnsen, S., Kelber, A., Warrant, E., Sweeney, A. M., Widder, E. A., Lee, R. L. J., et al. (2006). Crepuscular and nocturnal illumination and its effects on color perception by the nocturnal hawkmoth Deilephila elpenor. J Exp Biol, 209(Pt 5), 789–800.
Abstract: Recent studies have shown that certain nocturnal insect and vertebrate species have true color vision under nocturnal illumination. Thus, their vision is potentially affected by changes in the spectral quality of twilight and nocturnal illumination, due to the presence or absence of the moon, artificial light pollution and other factors. We investigated this in the following manner. First we measured the spectral irradiance (from 300 to 700 nm) during the day, sunset, twilight, full moon, new moon, and in the presence of high levels of light pollution. The spectra were then converted to both human-based chromaticities and to relative quantum catches for the nocturnal hawkmoth Deilephila elpenor, which has color vision. The reflectance spectra of various flowers and leaves and the red hindwings of D. elpenor were also converted to chromaticities and relative quantum catches. Finally, the achromatic and chromatic contrasts (with and without von Kries color constancy) of the flowers and hindwings against a leaf background were determined under the various lighting environments. The twilight and nocturnal illuminants were substantially different from each other, resulting in significantly different contrasts. The addition of von Kries color constancy significantly reduced the effect of changing illuminants on chromatic contrast, suggesting that, even in this light-limited environment, the ability of color vision to provide reliable signals under changing illuminants may offset the concurrent threefold decrease in sensitivity and spatial resolution. Given this, color vision may be more common in crepuscular and nocturnal species than previously considered.
Rich, C., Longcore, T., & editors. (2006). Ecological Consequences of Artificial Night Lighting. Island Press., .
Marchant, P. R. (2006). Investigating whether a crime reduction measure works. Radical Statistics, 91.
Abstract: Crime is a serious business. It causes great distress and fear. It costs a lot
to deal with its consequences. In these regards crime shares much with
the problem of ill-health and disease. The application of sound science and
statistics has allowed great strides to be made in dealing with problems of
ill health. Medical statistics is one of the recognised, established
disciplines involved in researching healthcare.
The parallels between research in crime reduction and in healthcare do
appear to differ in terms of quality. Although there is still room for
considerable improvement in researching health-care, an investigation
into the underpinning of statistical methods used indicates that the
problems are substantially worse in the study of crime. The consideration
given to statistics in crime studies seems rather flimsy, yet important
claims are made which are statistical at source and may affect policy, and
so can have considerable costs attached. Therefore, for example, it is
important to know whether the underlying crime level has really changed,
rather than just being the result of perhaps sampling variation or some
artefact giving rise to statistical bias or systematic error. This is necessary
when trying to determine whether a Crime Reduction Intervention (CRI)
has actually worked.
I started examining the scientific basis of the claim for the effectiveness for
one particular CRI, basically because I was concerned about negative side
effects and I thought the claim implausible. I remain concerned and
unconvinced. The statistical issues and concerns I raise apply also to
investigating other CRIs and to existing published analyses.
This piece extends work presented in Marchant (2006); earlier work on the
statistical issues involved can be found in Marchant (2005a, b; 2004).
Fouquet, R., & Pearson, P. J. (2006). Seven centuries of energy services: The price and use of light in the United Kingdom (1300-2000). Energy Journal, 27, 139–177.
Abstract: Before the mid-eighteenth century, most people lived in near-complete
darkness except in the presence of sunlight and moonlight. Since then, the provision
of artificial light has been revolutionised by a series of innovations in appliances,
fuels, infrastructures and institutions that have enabled the growing demands of
economic development for artificial light to be met at dramatically lower costs:
by the year 2000, while United Kingdom GDP per capita was 15 times its 1800
value, lighting services cost less than one three thousandth of their 1800 value,
per capita use was 6,500 times greater and total lighting consumption was 25,000
times higher than in 1800. The economic history of light shows how focussing on
developments in energy service provision rather than simply on energy use and
prices can reveal the âtrueâ declines in costs, enhanced levels of consumption
and welfare gains that have been achieved. While emphasising the value of past
experience, the paper also warns against the dangers of over-reliance on past
trends for the long-run forecasting of energy consumption given the potential for the
introduction of new technologies and fuels, and for rebound and saturation effects.
Xavier Kerola, D. (2006). Modelling artificial night-sky brightness with a polarized multiple scattering radiative transfer computer code: Modelling artificial night-sky brightness. Monthly Notices of the Royal Astronomical Society, 365(4), 1295–1299.
Abstract: As part of an ongoing investigation of radiative effects produced by hazy atmospheres, computational procedures have been developed for use in determining the brightening of the night sky as a result of urban illumination. The downwardly and upwardly directed radiances of multiply scattered light from an offending metropolitan source are computed by a straightforward Gauss-Seidel (G-S) iterative technique applied directly to the integrated form of Chandrasekhar's vectorized radiative transfer equation. Initial benchmark night-sky brightness tests of the present G-S model using fully consistent optical emission and extinction input parameters yield very encouraging results when compared with the double scattering treatment of Garstang, the only full-fledged previously available model.