Many of the wells, toilets and sanitation platforms haven't been completed as hoped, because getting hold of building materials is taking longer than thought; construction methods also require patience as pits need to sink before latrines can be completed.
Immunolocalization methods also require the generation of highly specific antibodies, which may not be available for every viral protein.
Other methods such as instrumental variable analysis are being employed to enable stronger causal inference but these methods also require fulfillment of several key assumptions that may or may not be realistic.
These methods also require the use of toxic and environmentally polluting substances for the syntheses [10, 11].
These methods also require strongly basic, toxic, high-boiling, polar solvents, namely HMPA, quinolone, or N,N-dimethylacetamide.
The methods also require that the inverse covariance matrix be calculated, but this is less of a concern for two reasons.
Among image segmentation methods, Hough transform requires a computational load which increases with the number of noise pixels, level set methods also require a high computational load, and some other methods assume that the contours are one-pixel wide.
Solution based capture methods also require smaller amounts of input DNA, which is especially important when clinical samples are studied.
The current cobalamin assay methods also require attention.
