?. Pr, ?. ??, ?. A. T??t-t??, ?. ??, ?. ?t?-t? et al., r???? s i ?? ?r??? a ?t s??? ??t? ? 1 ? ????? t?? ???? ??ss???? ???t????t??? ?r?? s i ?s t? ????? ??r??? ? 1 = 4 ? ? 1 ??? ?r? b? ???t ?s? (a, ? 1 ) ?s t?? ???? ??ss???? ??? t? r???? s i ?

?. ?-rs??-t??, ?. , ?. ??-?-?-?-tr?, ?. , ?. ?. et al., } ?r????ts d ?r?? ?r??? ??????s? ?t ??r??s b t? ?r? ??r???r?? ?? ??r tr??s??t???? t?? ????ss?t? t? ????? t?? ??t???t? t? r??? t?? st?t?s ?? t???r ???????rs ????????ts t??s?