Temporary participating group

Sometimes anti addition isn t observed. Temporary participation of a neighboring group can give unusual stereochemical or regiochemical results. 

Unless prior written approval has been obtained from the Director-General, observers will not be permitted to attend meetings of the Scientific Advisory Board, nor of the temporary working groups. Any observers who do participate, shall do so without cost to the OPCW. 

For the present heterogeneous system (Mn-support-GP-tacn + PO), the structure and the solvent effects in the catalytic experiments resemble most those of the latter, hexadentate complexes. For such hexadentate complexes, a temporary removal of one of the pendant arms is necessary to create a coordinative vacancy on the metal. The particular role of methanol might be to assist in the temporary deligation via hydrogen bond formation with 2-OH-alkyl groups. The system is unique in that the covalent fink to the surface can participate in the metal coordination via the 2-hydroxy group, as indicated by the arrow in Scheme 1. 

The same women also took cognitive tests, and these brain changes showed a correlation with impairment of concentration and memory. In a later study, the team looked at similar groups of women three years after treatment, some of whom had participated in the original study. By that point, the researchers found no evidence of structural change and no evidence of reduced cognitive abilities. The conclusion If cognitive abilities return, then the effects of chemotherapy on brain structure may be temporary as well, at least in a subset of women. 

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