Investigating Instructor Talk in Novel Contexts: Widespread Use, Unexpected Categories, and an Emergent Sampling Strategy.

Instructor Talk-noncontent language used by instructors in classrooms-is a recently defined and promising variable for better understanding classroom dynamics. Having previously characterized the Instructor Talk framework within the context of a single course, we present here our results surrounding the applicability of the Instructor Talk framework to noncontent language used by instructors in novel course contexts. We analyzed Instructor Talk in eight additional biology courses in their entirety and in 61 biology courses using an emergent sampling strategy.

Classroom sound can be used to classify teaching practices in college science courses.

Active-learning pedagogies have been repeatedly demonstrated to produce superior learning gains with large effect sizes compared with lecture-based pedagogies. Shifting large numbers of college science, technology, engineering, and mathematics (STEM) faculty to include any active learning in their teaching may retain and more effectively educate far more students than having a few faculty completely transform their teaching, but the extent to which STEM faculty are changing their teaching methods is unclear. Here, we describe the development and application of the machine-learning-derived algorithm Decibel Analysis for Research in Teaching (DART), which can analyze thousands of hours of STEM course audio recordings quickly, with minimal costs, and without need for human observers.

A profile of carbohydrate metabolites in the fasting northern elephant seal.

Northern elephant seals endure prolonged periods of food deprivation at multiple life-history stages and simultaneous with energetically costly activities-including reproduction and development. Most mammals decrease their energy expenditure while fasting, with simultaneous reductions in gluconeogenesis and circulating glucose concentration. Paradoxically, elephant seals maintain high rates of both energy expenditure and gluconeogenesis, and high blood glucose concentrations throughout fasting.

Water-soluble vitamin homeostasis in fasting northern elephant seals (Mirounga angustirostris) measured by metabolomics analysis and standard methods.

Despite the importance of water-soluble vitamins to metabolism, there is limited knowledge of their serum availability in fasting wildlife. We evaluated changes in water-soluble vitamins in northern elephant seals, a species with an exceptional ability to withstand nutrient deprivation. We used a metabolomics approach to measure vitamins and associated metabolites under extended natural fasts for up to 7 weeks in free-ranging lactating or developing seals.

Mouse spermatozoa contain a nuclease that is activated by pretreatment with EGTA and subsequent calcium incubation.

We demonstrated that mouse spermatozoa cleave their DNA into approximately 50 kb loop-sized fragments with topoisomerase IIB when treated with MnCl(2) and CaCl(2) in a process we term sperm chromatin fragmentation (SCF). SCF can be reversed by EDTA. A nuclease then further degrades the DNA in a process we term sperm DNA degradation (SDD).

Paternal pronuclear DNA degradation is functionally linked to DNA replication in mouse oocytes.

We recently demonstrated that mouse spermatozoa contain a mechanism to degrade their DNA into loop-sized fragments of about 50 kb, mediated by topoisomerase IIB, termed sperm chromatin fragmentation (SCF). SCF is often followed by a more complete digestion of the DNA with a sperm nuclease. When SCF-induced spermatozoa are injected into oocytes, the paternal pronuclei degrade their DNA after the initiation of DNA synthesis, but the maternal pronuclei are unaffected and replicate normally.