We present two new dynamical tests of the biasing hypothesis. The first is based on the amplitude and the shape of the galaxy-galaxy correlation function, xi g(r), where r is the separation of the galaxy pair. The second test uses the mean relative peculiar velocity for galaxy pairs, v12(r). This quantity is a measure of the rate of growth of clustering and it is related to the two-point correl...

We propose a new analytic approximation for the luminosity function of galaxies. The suggested expression behaves like the Schechter function at the faint end (φ ∼ L) but departs considerably at the bright end (L >> L∗). We argue here that such a behavior may provide a better fit for the current observational data than does the Schechter function. Its practical interest is stressed by consideri...

UV photoactivation of a mixture of benzophenone and ammonium phosphomolybdate (APM) in the solid state splits adsorbed moisture, resulting in selectively hydroxylated benzophenone and leaving an electron trapped in green (reduced) solid APM.

Environmental health policy decisions are characterized by irreversibility and uncertainty of an economic, ecological and biomedical nature. For this reason decision-makers may choose to exercise when possible some discretion over the timing and scope of policy. Problems of this kind fall within the framework of the theory of irreversible investments as applied to the sunk costs and sunk bene t...

The effects of airborne particulate matter (“aerosols”) on clouds (known as the “aerosol indirect effect”) are potentially one of the largest impacts humans have on climate. Even more important, the indirect effect is currently thought to have a net climatic cooling effect, largely offsetting the warming from greenhouse gases. Despite its importance, the indirect effect is one of the most uncer...

Anniversary of the founding of Resources for the Future. This paper would not have been possible without my collaboration with Kenneth Chay on a series of papers on the health impacts of airborne particulates pollution. This paper discusses some of the results from our papers, but even more importantly our collaboration has sharpened my thinking about empirical work and has directly influenced ...

There is concern regarding the heterogeneity of exposure to airborne particulate matter (PM) across urban areas leading to negatively biased health effects models. New, low-cost sensors now permit continuous and simultaneous measurements to be made in multiple locations. Measurements of ambient PM were made from October to April 2015-2016 and 2016-2017 to assess the spatial and temporal variabi...

UNLABELLED Quick information on airborne infectious disease transmission in airliner cabins is essential to reduce the risk of infection of passengers and crew members. This investigation proposed a one-dimensional analytical model that can predict the longitudinal transmission of airborne contaminants or disease viruses inside an airliner cabin. The model considered both diffusive and convecti...

BACKGROUND There is a strong need for laboratory in vitro test systems for the toxicity of airborne particulate matter and nanoparticles. The measurement of oxidative stress potential offers a promising way forward. OBJECTIVES A workshop was convened involving leading workers from the field in order to review the available test methods and to generate a Consensus Statement. DISCUSSIONS Work...