Scientific Opinion on the safety and efficacy of iron compounds (E1) as feed additives for all species: Ferrous sulphate monohydrate based on a dossier submitted by Kronos International, Inc.

Ferrous sulphate monohydrate is safe when supplied up to a maximum iron content per kilogram complete feedingstuff of 450 mg for bovines and poultry, 500 mg for ovines, 600 mg for pets, and 750 mg for other species/categories, except horses and fish; for piglets up to one week before weaning a maximum of 250 mg Fe/day is considered safe. Because of insufficient data on horses and fish, as a provisional measure, the current value (750 mg Fe/kg) could be maintained. The values for total dietary iron for pigs, ovines, horses, fish and other species/categories (except poultry, bovines and pets) are in line with those currently authorised. Iron from ferrous sulphate monohydrate is unlikely to modify the iron concentration in edible tissues and products of animal origin. Consumer exposure in the EU is not associated with a risk of excess iron intake to the general population. Therefore, the FEEDAP Panel does not foresee any concern for consumer safety resulting from the use of ferrous sulphate monohydrate in animal nutrition, provided that the maximum iron content in complete feedingstuffs is respected. Ferrous sulphate monohydrate is irritant and corrosive to the skin, eyes and respiratory tract. The additive contains up to 109 mg Ni/kg. Nickel is a dermal and respiratory sensitiser, and inhalation may cause lung cancer. Thus, handling the additive poses a risk to the user/worker. Considering the high concentration of iron and sulphur in soil and water, the supplementation of feed with the additive is not expected to pose an environmental risk. Ferrous sulphate monohydrate is an effective iron source for all animal species and categories. The FEEDAP Panel recommends that the currently authorised maximum iron content in complete feed be reduced for bovines and poultry from 750 to 450 mg Fe/kg, and for pets from 1250 to 600 mg Fe/kg

Nothing Lasts Forever: Environmental Discourses on the Collapse of Past Societies

The study of the collapse of past societies raises many questions for the theory and practice of archaeology. Interest in collapse extends as well into the natural sciences and environmental and sustainability policy. Despite a range of approaches to collapse, the predominant paradigm is environmental collapse, which I argue obscures recognition of the dynamic role of social processes that lie at the heart of human communities. These environmental discourses, together with confusion over terminology and the concepts of collapse, have created widespread aporia about collapse and resulted in the creation of mixed messages about complex historical and social processes

Impaired immunological synapse in sperm associated antigen 6 (SPAG6) deficient mice

This work is supported by grant RO1AI18697 from NIAID/NIH, American Asthma Foundation 11-0094 AAF, VCU School of Medicine Bridge grant, NIH HD076257, and VCU Massey Cancer Award. Flow cytometry is supported by the Massey Cancer Center Core P30 CA16059. Microscopy was performed at the VCU Department of Neurobiology and Anatomy Facility, supported in part with funding from NIH-NINDS center core grant 5P30N5S047463

Population and Environmental Correlates of Maize Yields in Mesoamerica: a Test of Boserup’s Hypothesis in the Milpa

Using a sample of 40 sources reporting milpa and mucuna-intercropped maize yields in Mesoamerica, we test Boserup’s (1965) prediction that fallow is reduced as a result of growing population density. We further examine direct and indirect effects of population density on yield. We find only mixed support for Boserupian intensification. Fallow periods decrease slightly with increasing population density in this sample, but the relationship is weak. Controlling for other covariates, fallow-unadjusted maize yields first rise then fall with population density. Fallow-adjusted maize yields peak at 390 kg/ha/yr for low population densities (8 persons / km2) and decline to around 280 kg/ha/yr for the highest population densities observed in our dataset. Fallow practices do not appear to mediate the relationship between population density and yield. The multi-level modeling methods we adopt allow for data clustering, accurate estimates of group-level variation, and they generate conditional predictions, all features essential to the comparative study of prehistoric and contemporary agricultural yields