Scenarios for optimizing potato productivity in a lunar CELSS

The use of controlled ecological life support system (CELSS) in the development and growth of large-scale bases on the Moon will reduce the expense of supplying life support materials from Earth. Such systems would use plants to produce food and oxygen, remove carbon dioxide, and recycle water and minerals. In a lunar CELSS, several factors are likely to be limiting to plant productivity, including the availability of growing area, electrical power, and lamp/ballast weight for lighting systems. Several management scenarios are outlined in this discussion for the production of potatoes based on their response to irradiance, photoperiod, and carbon dioxide concentration. Management scenarios that use 12-hr photoperiods, high carbon dioxide concentrations, and movable lamp banks to alternately irradiate halves of the growing area appear to be the most efficient in terms of growing area, electrical power, and lamp weights. However, the optimal scenario will be dependent upon the relative 'costs' of each factor

References

www.biogeosciences-discuss.net/11/8373/2014/ doi:10.5194/bgd-11-8373-2014 © Author(s) 2014. CC Attribution 3.0 License. This discussion paper is/has been under review for the journal Biogeosciences (BG). Please refer to the corresponding final paper in BG if available. Wind-induced upwelling in the Kerguele

Further studies of space-time clustering of Burkitt's lymphoma in Uganda.

All hospital-treated cases of Burkitt's lymphoma (BL), with onset of symptoms in the period 1963-68 and resident in the Lango and Acholi districts of Uganda, were identified. The average annual incidence of BL in the 6-year period was 1-87 X 10(-5), similar to that in the adjacent West Nile district. Contrary to findings in other areas of Uganda, there was no evidence of seasonal variation in the onset of cases, nor of space-time clustering, nor of a decline in the incidence of BL in the study period. An inverse relationship was noted between the median age at onset of BL and the incidence of the disease in different areas of Uganda, a finding consistent with intense malarial infection being a precipitating factor for BL. The variable observations with respect to space-time clustering of BL and seasonal variation in incidence in different areas remains unexplained, but it is suggested that a closer study of the patterns of malarial infection in these areas may help to account for the findings

Magnetic structure of the swedenborgite compound CaBaMn2 Fe 2 O7 derived by powder neutron diffraction and Mössbauer spectroscopy

We present a study combining neutron diffraction and 57 Fe Mössbauer spectroscopy on a powder sample ofCaBaMn 2 Fe 2 O7 belonging to the large family of swedenborgite compounds. The undistorted hexagonal crystal structure (space group P63mc) is preserved down to low temperatures, and all employed techniques reveal a transition into a magnetically long-range ordered phase at TN = 205 K. The magnetic Bragg peak intensities from the powder diffraction patterns together with a symmetry analysis of the employed models unambiguously reveal the classical √3 × √3 magnetic structure on a hexagonal lattice with propagation vector q = ( 1/3 1/3 0). The nuclear Bragg peak intensities allowed the statistical distribution of Fe and Mn ions on both trigonal and kagome sites of the complex swedenborgite structure to be analyzed which was considered to explain the complex shape of the Mössbauer spectra