The high-production-volume chemical 4,4'-methylenedianiline (4,4'-MDA) is an aromatic amine used to manufacture 4,4'-methylenedianiline diisocyanate for polyurethane production. Based on 4,4'-MDA's octanol/water partition coefficient (K ) and correlations with the transpiration stream concentration factor (TSCF), significant plant uptake and root-to-shoot transfer are predicted. However, most correlations between K and TSCF were developed for neutral organics and may not be applicable for ionizable bases such as 4,4'-MDA.
View Article and Find Full Text PDFAmphiphilic kanamycins bearing hydrophobic modifications at the 6″ position have attracted interest due to remarkable antibacterial-to-antifungal switches in bioactivity. In this report, we investigate a hurdle that hinders practical applications of these amphiphilic kanamycins: a cost-effective synthesis that allows the incorporation of various connecting functionalities to which the hydrophobic moieties are connected to the kanamycin core. A cost-effective tosylation enables various modifications at the 6″ position, which is scalable to a 90-g scale.
View Article and Find Full Text PDFStudies of rodents have shown that both forced and voluntary chronic exercise cause increased hindlimb bone diameter, mass, and strength. Among species of mammals, "cursoriality" is generally associated with longer limbs as well as relative lengthening of distal limb segments, resulting in an increased metatarsal/femur (MT/F) ratio. Indeed, we show that phylogenetic analyses of previously published data indicate a positive correlation between body mass-corrected home range area and both hindlimb length and MT/F in a sample of 19 species of Carnivora, although only the former is statistically significant in a multiple regression.
View Article and Find Full Text PDF