We present the frailtyHL package for fitting semi-parametric frailty models using hlikelihood. This package allows lognormal or gamma frailties for random-effect distribution, and it fits shared or multilevel frailty models for correlated survival data. Functions are provided to format and summarize the frailtyHL results. The estimates of fixed effects and frailty parameters and their standard ...

The review summarizes studies on the detoxification effects of water-soluble humic substances (HS), which are products natural transformation organic in soils and bottom sediments that serve as detoxifying agents water solutions. HS microorganisms quite complex: neutralize free pollutants (indirect bioeffects) also stimulate protective response organisms (direct bioeffects). Prospects potential...