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1,2-Indanedione is considered the most sensitive amino acid reagent currently available for routine use as a fingermark detection technique on porous substrates. The method is generally applied by treating items with a solution of the reagent, followed by the application of heat to accelerate the reaction. Despite the high sensitivity demonstrated by this technique, the use of organic solvents and heat can be problematic for some substrates. For example, polar solvents and heat will darken thermal printer paper. Polar solvents will also diffuse writing inks on documents and may also remove other forensic traces such as explosive and illicit drug residues. The solvent-free application of amino acid reagents has been investigated by a number of research groups as a means of overcoming such issues. Examples include vacuum sublimation (low-pressure vaporization) and "dry-transfer" methods. For the latter, items to be treated are sandwiched between sheets of reagent-impregnated paper. Solventless methods can alleviate the need for the storage and use of large volumes of potentially hazardous solvents, including solvents that are being phased out because of their global warming potential. In this study, a method for applying indanedione under vacuum using a commercially available vacuum oven was optimized and applied to treat fingermarks on a range of substrates. The results were compared against those obtained using conventional and dry-transfer techniques. Although a vacuum method was found to be feasible, it was generally outperformed by conventional indanedione treatment. However, encouraging results were obtained on some nonporous surfaces, and this shows promise for future investigation. [ABSTRACT FROM AUTHOR]

The Paris Agreement of COP21 set a goal of holding global average temperature increases to below 2 °C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 °C. This is particularly relevant for the African context where temperatures are likely to warm faster than the global average and where the magnitude of change will be regionally heterogeneous. Most studies that provide information over Africa under specific global warming levels have used data from global models, however global models poorly resolve local scale forcing (e.g. topography) nor the internal climate variability of a region. Although downscaling using regional climate models can address these issues, we found only one paper that had used downscaled data for GWL studies over Africa. During 2018 the CORDEX-Africa campaign investigated the impact of 1.5 and 2 degrees of global warming over many regions of sub-Saharan Africa and compiled the results for a special issue of nine papers in ERL. This paper reports on some of the key regional findings of the analysis of 25 CORDEX downscalings, including the impact of the extra 0.5 degrees of warming between 1.5 and 2 degrees on particular extremes and the differences noted between the driving GCMs and downscaled results. We also briefly discuss the impact of the papers in the IPCC SR15 and their contribution to the development of adaptation and mitigation policies. [ABSTRACT FROM AUTHOR]