A long-unresolved question in the developmental biology of Drosophila melanogaster has been whether methyl farnesoid hormones secreted by the ring gland are necessary for larval maturation and metamorphosis. In the present study, we have used RNAi techniques to inhibit 3-Hydroxy-3-Methylglutaryl CoA Reductase (HMGCR) expression selectively in the corpora allatal cells that produce the circulating farnesoid hormones. The developing larvae manifest a number of developmental, metabolic and morphogenetic derangements. These defects included the exhibition of an "ultraspiracle" death phenotype at the 1 st to 2 nd larval molt, similar to that exhibited by animals that are null for the farnesoid receptor ultraspiracle. The few larvae surviving past a second lethal period at the 2 nd to 3 rd instar larval molt, again with "ultraspiracle" phenotype, often became developmentally arrested after either attaining a misformed puparium or after formation of the white pupa. Survival past the "ultraspiracle" lethal phenotype could be rescued by dietary provision of an endogenous dedicated precursor to the three naturally secreted methyl farnesoid hormones. In addition to these developmental and morphogenetic defects, most larvae that survived to the late second instar exhibited a posterior-originating melanization of the tracheal system. These results support the hypothesis that larval methyl farnesoid hormones are necessary for larval survival and morphogenetic transformation through the larval and pupal metamorphic processes.

Although social workers have an elevated risk of infection with COVID-19, no previous studies have investigated the virus’s impact on practitioners. Using survey data (N = 441), this study identified associations between stress, depression, and COVID-related factors and explored the role of social connectedness as a moderator for mental health among Ohio social workers. The results of the study showed that among social workers with a positive COVID-19 diagnosis, 70 percent experienced moderate/high levels of stress, and 37 percent met the criteria for clinical depressive symptoms. Results from the multiple regression analyses showed that perceived stress was positively associated with a positive COVID-19 diagnosis for social workers, and depression was positively associated with working with a client with a positive COVID-19 diagnosis. An interaction effect was also identified between social connectedness and social workers’ mental health. These findings suggest that the provision of individual or organizational interventions that emphasize social connectedness can help to protect social workers’ mental health.