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Understanding the rate at which STEM faculty move from traditional, lecture-intensive teaching practices to more effective, student-centered practices and the institutional conditions that favor this shift are crucial for supporting faculty change. This study investigated the instructional practices of biology, chemistry, and physics faculty at research-intensive institutions and explored the institutional structures that support student-centered instruction. Faculty members (N = 1,456) from 66 institutions reported on their frequency of use of a variety of instructional practices (at two time points within the last five years) and the support structures present at their institution using the Change in Implementation of Pedagogical Practices (ChIPP) survey. An index was created for measuring use of student-centered instructional strategies at these two time points, providing a measure of change over time. About 30% of all respondents reported increases in the frequency of student-centered teaching strategies over time. For all faculty, participation in institutional faculty communities was predictive of change toward student-centered pedagogies. Faculty teaching lower-division courses were more likely to use at a higher number of student-centered strategies every class, compared to their upper-division colleagues. Factors associated with greater use of student-centered strategies in lower-division courses were institutional financial opportunities for course reform, use of classrooms designed to promote active learning, and engagement in STEM education research. Only one factor, engagement in professional development, was associated with greater use of student-centered strategies in upper-division courses. These findings suggest that pedagogical change is occurring at research-intensive institutions and may be fostered through specific support structures.

Despite decades of research indicating that active learning techniques (ALTs) are more effective than traditional lecture, ALTs are not widely implemented in STEM undergraduate classrooms. While ALT implementation is happening in a number of disciplines, including the geosciences, most STEM teaching remains lecture-based. Understanding the contexts that correlate with ALT adoption may allow expanded implementation. ALT use was documented among STEM pre-tenure and tenured faculty respondents across 66 research-intensive, U.S. universities, using the Change in Implementation of Pedagogical Practices survey. Personal, professional, and institutional/departmental factors were analyzed for association with ALT use. Most respondents reported using some ALTs in their teaching, with no significant distinctions between pre-tenure and tenured faculty. Teaching was perceived to carry less weight in practice (e.g., in tenure and promotion decisions) than the theoretical value stated by institutions (e.g., in faculty assignments and hiring). ALT use among tenured faculty was predicted by number of recent publications, their knowledge of education initiatives, and receiving informal feedback on their teaching. ALT use among pre-tenure faculty was predicted by the number of STEM education talks given. Perception of obstacles was a negative predictor of ALT use among tenured faculty only, though both pre-tenure and tenured faculty identified barriers to ALT use. Considering these identified barriers and how to remove them could potentially increase ALT use. The findings that ALT use by tenured faculty was predicted by number of recent publications and that grant funding was neither a positive nor negative predictor of ALT use suggest that ALT use does not hinder faculty research productivity.

Based on positive student outcomes, providing research experiences from early undergraduate years is recommended for science, technology, engineering, and mathematics (STEM) majors. To this end, we designed a novel research experience called the "STEMCats Research Experience" (SRE) for a cohort of 119 second-semester freshmen with diverse college preparatory levels, demographics, and academic majors. The SRE targeted student outcomes of enhancing retention in STEM majors, STEM competency development, and STEM academic performance. It was designed as a hybrid of features from apprenticeship-based traditional undergraduate research experience and course-based undergraduate research experience designs, considering five factors: 1) an authentic research experience, 2) a supportive environment, 3) current and future needs for scale, 4) student characteristics and circumstances, and 5) availability and sustainability of institutional resources. Emerging concepts for facilitating and assessing student success and STEM curriculum effectiveness were integrated into the SRE design and outcomes evaluation. Here, we report the efficient and broadly applicable SRE design and, based on the analysis of institutional data and student perceptions, promising student outcomes from its first iteration. Potential improvements for the SRE design and future research directions are discussed.

Introduction: All eukaryotes and at least some prokaryotes express the capacity to anticipate and adapt to daily changes of light and temperature in their environments. These circadian programs are fundamental features of many forms of life. Cyanobacteria were the first prokaryotes to have demonstrated circadian gene expression. Recently, a circadian rhythm was also discovered in an unrelated bacterium, Klebsiella aerogenes, a human gut commensal and nosocomial pathogen. Methods: Here we characterize new clock-controlled genes with spatial differences in expression using a bacterial luciferase reporter. These include dephosphocoenzyme A kinase (coaE), manganese transporter, H-dependent (mntH) and a gene identified as filamenting temperature-sensitive mutant Z (ftsZ). Results and Discussion: The data show that all three reporter constructs exhibited circadian variation, although only PmntH::luxCDABE reporter strains were synchronized by melatonin. Additionally, we show that K. aerogenes divides rhythmically in vitro and that these bacteria may alternate between exponential and stationary cells. Together, these findings provide a deeper understanding of K. aerogenes. [ABSTRACT FROM AUTHOR]

Hoogerwerf WA, Shahinian VB, Cornelissen G, Halberg F, Bostwick J, Timm J, Bartell PA, Cassone VM. Rhythmic changes in colonic motility are regulated by period genes. Am J Physiol Gastrointest Liver Physiol 298: G143-G150, 2010. First published November 19, 2009; doi: 10.1152/ajpgi.00402.2009.--Human bowel movements usually occur during the day and seldom during the night, suggesting a role for a biological clock in the regulation of colonic motility. Research has unveiled molecular and physiological mechanisms for biological clock function in the brain; less is known about peripheral rhythmicity. This study aimed to determine whether clock genes such as period I (per1) and period2 (per2) modulate rhythmic changes in colonic motility. Organ bath studies, intracolonic pressure measurements, and stool studies were used to examine measures of colonic motility in wild-type and per1per2 double-knockout mice. To further examine the mechanism underlying rhythmic changes in circular muscle contractility, additional studies were completed in neuronal nitric oxide synthase (nNOS) knockout mice. Intracolonic pressure changes and stool output in vivo, and colonic circular muscle contractility ex vivo, are rhythmic with greatest activity at the start of night in nocturnal wild-type mice. In contrast, rhythmicity in these measures was absent in perlper2 double-knockout mice. Rhythmicity was also abolished in colonic circular muscle contractility of wild-type mice in the presence of [N.sup.[omega]]-nitro-L-arginine methyl ester and in nNOS knockout mice. These findings suggest that rhythms in colonic motility are regulated by both clock genes and a nNOS-mediated inhibitory process and suggest a connection between these two mechanisms. biological rhythms; clock genes; circadian; nNOS doi: 10.1152/ajpgi.00402.2009

Molecular aspects of the circadian clock in the cyanobacterium Synechococcus elongatus have been described in great detail. Three-dimensional structures have been determined for the three proteins, KaiA, KaiB and KaiC, that constitute a central oscillator of the clock. Moreover, a temperature-compensated circadian rhythm of KaiC phosphorylation can be reconstituted in vitro with the addition of KaiA, KaiB and ATP. These data suggest a relatively simple circadian system in which a single oscillator provides temporal information for all downstream processes. However, in vivo the situation is more complex, and additional components contribute to the maintenance of a normal period, the resetting of relative phases of circadian oscillations, and the control of rhythms of gene expression. We show here that two well-studied promoters in the S. elongatus genome report different circadian periods of expression under a given set of conditions in wild-type as well as mutant genetic backgrounds. Moreover, the period differs between these promoters with respect to modulation by light intensity, growth phase, and the presence or absence of a promoter-recognition subunit of RNA polymerase. These data contrast sharply with the current clock model in which a single Kai-based oscillator governs circadian period. Overall, these findings suggest that complex interactions among the circadian oscillator, perhaps other oscillators, and other cellular machinery result in a clock that is plastic and sensitive to the environment and to the physiological state of the cell.

Byline: Vincent M. Cassone (Center for Research on Biological Clocks, Department of Biology, Texas A & M University, College Station, TX, vmc@mail.bio.tamu.edu); Paul A. Bartell (Center for Research on Biological [...]