Felids have a wide range of locomotor activity patterns and maximal running speeds, including the very fast cheetah (Acinonyx jubatas), the roaming tiger (Panthera tigris), and the relatively sedentary domestic cat (Felis catus). As previous studies have suggested a relationship between the amount and type of activity and the myosin heavy chain (MHC) isoform composition of a muscle, we assessed the MHC isoform composition of selected hindlimb muscles from these three felid species with differing activity regimens. Using gel electrophoresis, western blotting, histochemistry, and immunohistochemistry with MHC isoform-specific antibodies, we compared the MHC composition in the tibialis anterior, medial gastrocnemius (MG), plantaris (Plt), and soleus muscles of the tiger, cheetah, and domestic cat. The soleus muscle was absent in the cheetah. At least one slow (type I) and three fast (types IIa, IIx, and IIb) MHC isoforms were present in the muscles of each felid. The tiger had a high combined percentage of the characteristically slower isoforms (MHCs I and IIa) in the MG (62%) and the Plt (86%), whereas these percentages were relatively low in the MG (44%) and Plt (55%) of the cheetah. In general, the MHC isoform characteristics of the hindlimb muscles matched the daily activity patterns of these felids: the tiger has daily demands for covering long distances, whereas the cheetah has requirements for speed and power.

Skeletal muscle adapts to aerobic exercise training, in part, through fast‐to‐slow phenotypic shifts and an expansion of mitochondrial networks. Recent research suggests that the local and systemic benefits of exercise training also may be modulated by the mitochondrial‐derived peptide, MOTS‐c. Using a combination of acute and chronic exercise challenges, the goal of the present study was to characterize the interrelationship between MOTS‐c and exercise. Compared to sedentary controls, 4–8 weeks of voluntary running increased MOTS‐c protein expression ~1.5‐5‐fold in rodent plantaris, medial gastrocnemius, and tibialis anterior muscles and is sustained for 4–6 weeks of detraining. This MOTS‐c increase coincides with elevations in mtDNA reflecting an expansion of the mitochondrial genome to aerobic training. In a second experiment, a single dose (15 mg/kg) of MOTS‐c administered to untrained mice improved total running time (12% increase) and distance (15% increase) during an acute exercise test. In a final experiment, MOTS‐c protein translocated from the cytoplasm into the nucleus in two of six mouse soleus muscles 1 h following a 90‐min downhill running challenge; no nuclear translocation was observed in the plantaris muscles from the same animals. These findings indicate that MOTS‐c protein accumulates within trained skeletal muscle likely through a concomitant increase in mtDNA. Furthermore, these data suggest that the systemic benefits of exercise are, in part, mediated by an expansion of the skeletal muscle‐derived MOTS‐c protein pool. The benefits of training may persist into a period of inactivity (e.g., detraining) resulting from a sustained increase in intramuscular MOTS‐c proteins levels.

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Scientific writing requires a distinct style and tone, whether the writing is intended for an undergraduate assignment or publication in a peer-reviewed journal. From the first to the final draft, scientific writing is an iterative process requiring practice, substantial feedback from peers and instructors, and comprehensive proofreading on the part of the writer. Teaching writing or proofreading is not common in university settings. Here, we present a collection of common undergraduate student writing mistakes and put forth suggestions for corrections as a first step toward proofreading and enhancing readability in subsequent draft versions. Additionally, we propose specific strategies pertaining to word choice, structure, and approach to make products more fluid and focused for an appropriate target audience.

Introductory courses in biology often act as a gateway for students seeking careers in healthcare and science-related fields. As such, they provide a prime entry point for innovations seeking to enhance students’ learning of foundational content. Extant innovations and interventions have been found to positively impact students’ study strategy use with concomitant impacts on course exams and grades. These innovations, however, often have associated time and other costs, which may ultimately limit more widespread use. Our study builds on prior findings by exploring the extent to which students evidence increased use of effective study strategies after engaging in a brief (i.e., 15-min), online module requiring no financial cost for students or time commitment from instructors, and whether changes in students’ use of effective study strategies are associated with changes in exam performance. The present study employed a brief, online module designed to support undergraduate students’ (n = 98) use of effective study strategies in an introductory human anatomy and physiology course. Through a pretest-posttest design, students described the strategies they used to study and completed four cognitive and metacognitive subscales before and after engaging in a brief, online module designed to teach them about effective study strategies. Results were somewhat mixed: students evidenced a modest, statistically significant increase in the number of strategies used and changes in strategy use were associated with changes in exam score only for some measures. Notably, this relationship was not moderated by GPA, suggesting that the strength of the relationship between changes in strategy use and changes in exam scores were not different depending on students’ levels of prior academic performance. Taken together, the innovation was associated with increases in students’ exam scores, irrespective of GPA, but future research should explore the refinement and extension of the innovation to explore ways that increase efficacy and impact while still balancing sustainable implementation to account for challenges associated with instructor supervision and training, financial costs, and students’ time.

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