Sustained service: a community-driven framework for longitudinal service-learning.

This article was migrated. The article was marked as recommended. The sustained service four-year longitudinal framework for medical school service-learning is introduced and defined. Framework benefits include: students can engage deeply over time with both the people they serve and their colleagues, they are immersed in the social determinants of health in authentic contexts, and they grow in the expertise required to perform their service over time. The approach starts with a sophisticated community needs assessment that relies on systematic inclusion of community voices, community leader inputs, and systematic and data-saturated inputs. This needs assessment should result in a six to eight item list of the community's priority needs. All student service is then focused on the primary needs identified in the assessment. Goals of the framework are described: to make a difference with the community's priority needs; to grow the identity, skills and paradigms required of a community-responsive physician; and to strengthen student credentials through objective qualifications related to their sustained service. The culminating activity is a Capstone research project that focuses on the served population and gives students an opportunity to synthesize their experience. Initial results describing the community impact of service, the focus of service hours, and candid student reactions to the approach are presented. Discussions of findings and conclusions are offered.

A survey of new temperature-sensitive, embryonic-lethal mutations in C. elegans: 24 alleles of thirteen genes.

To study essential maternal gene requirements in the early C. elegans embryo, we have screened for temperature-sensitive, embryonic lethal mutations in an effort to bypass essential zygotic requirements for such genes during larval and adult germline development. With conditional alleles, multiple essential requirements can be examined by shifting at different times from the permissive temperature of 15°C to the restrictive temperature of 26°C. Here we describe 24 conditional mutations that affect 13 different loci and report the identity of the gene mutations responsible for the conditional lethality in 22 of the mutants. All but four are mis-sense mutations, with two mutations affecting splice sites, another creating an in-frame deletion, and one creating a premature stop codon. Almost all of the mis-sense mutations affect residues conserved in orthologs, and thus may be useful for engineering conditional mutations in other organisms. We find that 62% of the mutants display additional phenotypes when shifted to the restrictive temperature as L1 larvae, in addition to causing embryonic lethality after L4 upshifts. Remarkably, we also found that 13 out of the 24 mutations appear to be fast-acting, making them particularly useful for careful dissection of multiple essential requirements. Our findings highlight the value of C. elegans for identifying useful temperature-sensitive mutations in essential genes, and provide new insights into the requirements for some of the affected loci.