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The eastern migratory population of monarch butterflies (Danaus plexippus plexippus) has declined by >80% within the last two decades. One possible cause of this decline is the loss of ≥1.3 billion stems of milkweed (Asclepias spp.), which monarchs require for reproduction. In an effort to restore monarchs to a population goal established by the US Fish and Wildlife Service and adopted by Mexico, Canada, and the US, we developed scenarios for amending the Midwestern US landscape with milkweed. Scenarios for milkweed restoration were developed for protected area grasslands, Conservation Reserve Program land, powerline, rail and roadside rights of way, urban/suburban lands, and land in agricultural production. Agricultural land was further OPEN ACCESS RECEIVED

Cognitive impairments can increase significantly a person's level of risk for becoming or remaining homeless. Five topics are explored that address these impairments in preventing homelessness: (1) the nature and estimated prevalence of cognitive impairments among people who are homeless, especially those with vulnerabilities like mental illness or substance abuse; (2) the multiple origins of these impairments; (3) how these impairments impact services for people at risk for homelessness; (4) good practice approaches to handling cognitive impairments in homeless shelters, supported housing programs, and other service systems for people at risk for homelessness; and, (5) important research and practice issues requiring further action.

The T-DNA transfer process of Agrobacterium is activated following induction of expression of the Ti plasmid virulence (vir) genes. The virDI and virD2 gene products are required for the production of nicks at the T-DNA borders and for the generation of free linear single-stranded copies of the T-DNA region, T-strands. T-strands are complexed with proteins in vir-induced bacteria, since T-strands partition to the aqueous/phenol interface in non-Pronasetreated total cell extracts. To determine whether the proteins are tightly associated with T-strands, DNA-protein complexes were purified away from bulk proteins by adsorption to glass beads. A 58-kDa protein was specifically released from virinduced DNA-protein complexes after treatment with S1 nuclease to digest single-stranded DNA. The 58-kDa protein was identified as VirD2 by using VirD2-specific antibodies. The tight association of VirD2 with T-strands was shown directly by using VirD2-specific antibody to isolate T-strands. The 5' side of the borders nick sites on the Ti plasmid was also shown to be tightly associated with protein. The data suggest that after VirDl/VirD2-dependent nicking at the T-DNA borders, the VirD2 protein remains bound to the 5' end of the nick, and the VirD2 protein continues to bind tightly to this 5' end during unwinding (or displacement) of the T-strand from the Ti plasmid T-DNA region. The tight binding ofVirD2 to T-strands suggests that this protein has additional functions in T-strand generation and potentially in the later steps of T-DNA transfer.