Information seeking and evaluation: a multi-institutional survey of veterinary students.

OBJECTIVE: To practice evidence-based medicine, clinicians must be competent in information literacy (IL). Few studies acknowledge the critical role that reading strategies play in IL instruction and assessment of health professional students. The purpose of this study was to understand the information-seeking and evaluation behaviors of doctor of veterinary medicine (DVM) students in regard to scientific papers. METHODS: The authors studied DVM student behaviors across eight programs in North America using a web-based survey of closed- and open-ended questions about finding and evaluating scientific papers, including a task to read a linked scientific paper and answer questions about it. RESULTS: A total of 226 individuals responded to the survey. The sections of a scientific paper that were most commonly read were the abstract, introduction, and conclusions. Students who reported reading a higher proportion of scientific papers were more likely to feel confident in their abilities to interpret them. A third of respondents answered open-ended questions after the paper reading task. Respondents felt the least amount of confidence with one of the final steps of evidence-based medicine, that of interpreting the significance of the paper to apply it in veterinary medicine. CONCLUSIONS: DVM students may lack the skills needed to evaluate scientific literature and need more practice and feedback in evaluating and interpreting scientific papers. Librarians who support DVM students can (1) help DVM students to efficiently evaluate scientific literature, (2) seek training opportunities in alternative modes of teaching and learning IL skills, and (3) partner with veterinary faculty and clinicians to provide students with practice and feedback in information evaluation.

Sic1-induced DNA rereplication during meiosis.

Orderly progression through meiosis requires strict regulation of DNA metabolic events, so that a single round of DNA replication is systematically followed by a recombination phase and 2 rounds of chromosome segregation. We report here the disruption of this sequence of events in Saccharomyces cerevisiae through meiosis-specific induction of the cyclin-dependent kinase (CDK) inhibitor Sic1 mutated at multiple phosphorylation sites. Accumulation of this stabilized version of Sic1 led to significant DNA rereplication in the absence of normal chromosome segregation. Deletion of DMC1 abolished DNA rereplication, but additional deletion of RAD17 restored the original phenotype. Therefore, activation of the meiotic recombination checkpoint, which arrests meiotic progression at pachytene, suppressed DNA rereplication resulting from Sic1 stabilization. In contrast to deletion of DMC1, deletion of NDT80, which encodes a transcription factor required for pachytene exit, did not inhibit DNA rereplication. Our results provide strong evidence that CDK activity is required to prevent inappropriate initiation of DNA synthesis before the meiotic divisions.

Evidence for abscisic acid biosynthesis in Cuscuta reflexa, a parasitic plant lacking neoxanthin.

Abscisic acid (ABA) is a plant hormone found in all higher plants; it plays an important role in seed dormancy, embryo development, and adaptation to environmental stresses, most notably drought. The regulatory step in ABA synthesis is the cleavage reaction of a 9-cis-epoxy-carotenoid catalyzed by the 9-cis-epoxy-carotenoid dioxygenases (NCEDs). The parasitic angiosperm Cuscuta reflexa lacks neoxanthin, one of the common precursors of ABA in all higher plants. Thus, is C. reflexa capable of synthesizing ABA, or does it acquire ABA from its host plants? Stem tips of C. reflexa were cultured in vitro and found to accumulate ABA in the absence of host plants. This demonstrates that this parasitic plant is capable of synthesizing ABA. Dehydration of detached stem tips caused a big rise in ABA content. During dehydration, 18O was incorporated into ABA from 18O2, indicating that ABA was synthesized de novo in C. reflexa. Two NCED genes, CrNCED1 and CrNCED2, were cloned from C. reflexa. Expression of CrNCEDs was up-regulated significantly by dehydration. In vitro enzyme assays with recombinant CrNCED1 protein showed that the protein is able to cleave both 9-cis-violaxanthin and 9'-cis-neoxanthin to give xanthoxin. Thus, despite the absence of neoxanthin in C. reflexa, the biochemical activity of CrNCED1 is similar to that of NCEDs from other higher plants. These results provide evidence for conservation of the ABA biosynthesis pathway among members of the plant kingdom.