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McLaughlin, J. E.

Publications and source records attributed to McLaughlin, J. E..

2 recordsLinked to original sources

Standards needed? An Exploration of Qualifying Exams from a Literature Review and Website Analysis of University-Wide Polices

PurposeWhile known by many names, qualifying exams function as gatekeepers to graduate student advancement to PhD Candidacy, yet there has been little formal study on best qualifying exam practices particularly in biomedical and related STEM PhD programs. The purpose of this study was to examine the current state of qualifying exams through an examination of the literation and exploration of university policies. Design/methodology/approachWe conducted a literature review of studies on qualifying exams and completed an external evaluation of peer institutions and internal institutional qualifying exam requirements to inform our discussion of common practices of qualifying exams in doctoral training at a research-intensive institutions. FindingsOur research identified the need for more evidence-based research on qualifying exams, which are nearly universal as a major doctoral training milestone across US institutions of higher education. Our findings indicate a wide variety of qualifying exam formats, often lacking the establishment of explicit expectations and evidence for specific formats. This lack of understanding of best practices coupled with insufficient clarity has a real potential to disadvantage doctoral students, particularly first generation, underrepresented minority, international, and/or other trainees who are not privileged or socialized to navigate training environments with vague landmarks such as the qualifying exams. OriginalityThere are very few studies that evaluate qualifying exams in US doctoral education, particularly in STEM fields, and to our knowledge, there has been no analysis of campus wide policies on qualifying exams reported. The lack of evidence for best practices and the need for to evaluate the implementation and effectiveness of qualifying exams are discussed.

scientific communication and education↗

Detecting turnover among complex communities using null models: A case study with sky-island haemosporidian parasites

Turnover in species composition between sites, or beta diversity, is a critical component of species diversity that is typically influenced by geography, environment, and biotic interactions. Quantifying turnover is particularly challenging, however, in multi-host, multi-parasite assemblages where undersampling is unavoidable, resulting in inflated estimates of turnover and uncertainty about its spatial scale. We developed and implemented a framework using null models to test for community turnover in avian haemosporidian communities of three sky islands in the southwestern United States. We screened 776 birds for haemosporidian parasites from three genera (Parahaemoproteus, Plasmodium, and Leucocytozoon) by amplifying and sequencing a mitochondrial DNA barcode. We detected infections in 280 birds (36.1%), sequenced 357 infections, and found a total of 99 parasite haplotypes. When compared to communities simulated from a regional pool, we observed more unique, single-mountain haplotypes and fewer haplotypes shared among three mountain ranges than expected, indicating that haemosporidian communities differ to some degree among adjacent mountain ranges. These results were robust even after pruning datasets to include only identical sets of host species, and they were consistent for two of the three haemosporidian genera. The two more distant mountain ranges were more similar to each other than the one located centrally, suggesting that the differences we detected were due to stochastic colonization-extirpation dynamics. These results demonstrate that avian haemosporidian communities of temperate-zone forests differ on relatively fine spatial scales associated with adjacent sky-islands. Null models are essential tools for detecting turnover in complex, undersampled, and poorly known systems.

ecology↗