bluuebunny/crossref_metadata_2025_split huggingface dataset:
Does Size Really Matter? A Comparison of Class Size and Student Outcomes in Introductory Physiology Courses
Authors: Kroeker Carol Anne Gibbons 
Published: November 2023

Traditionally, it's been thought that small class size resulted in better student outcomes. As teaching styles change and inquiry‐based learning becomes more common, this may not necessarily be the case.This study examined student outcomes for introductory physiology courses of different sizes at two different institutions over a three year period. One course averaged 30 students per year while the other course averaged 200 students per year. Both courses were taught by the same instructor, using the same teaching materials, lecture style, and inquiry‐based techniques. The same hands‐on lab exercises were taught and the same lab report questions were assigned. Tutorials involved teaching the same case studies (by the instructor at the small institution and by teaching assistants under the direction of the instructor at the larger institution). Each course used the same exam questions and consisted of multiple choice and short answer formats. With class size being the only significant variable, it was possible to test if class size was a key factor in student success.Students in both courses (and in all years) were given a pre‐test to assess the student knowledge base at the beginning of the course. In all cases, the pre‐test showed similar levels of starting knowledge between the different‐sized courses (31.1±1.8% for the smaller course vs. 30.6±0.9% for the larger course). Student outcomes were compared between the classes by assessing exam grades (overall scores as well as individual question scores), comparing lab report grades, and by comparing final course grades. Assessment of all these parameters showed no significant difference between the two courses and this result was seen in each year of the study. Lab report grades, averaged over 5 lab reports, differed by less than 2% between the large and small courses (not a significant difference). Mean exam scores and final grade scores were also not significantly different for any of the years of the study. Course grades between the courses differed by less than 3±0.8%.These results would indicate that class size alone was not a significant factor in determining student outcomes. Students showed similar success in both large and small classes when all other factors were similar. Interactive lectures, as well as the use of case studies and other inquiry‐based learning methods may have a much greater influence on student learning and success than class size.
Physiology Labs at the Cutting Edge: Multidisciplinary Design of Systems and Devices for Physiology Measurements
Authors: Rozner Robert H , Batts Jacob T , Nossa Gianna K , Pullins Calvin , Pelaez Nancy 
Published: November 2023

Physiology as a discipline is uniquely positioned to engage undergraduate students in transformational research, which often involves multidisciplinary projects. However, physiology lab instruction is often centered around historical and not current physiology research methods. When students perform a protocol without realizing the relevant cross‐cultural and social impact from those methods, they miss the opportunity to discover whose interests are being served and the importance of physiology. In this study, a lab course arena was provided where students could solve real‐world physiology problems. Each module gave basic information, a problem, and protocols. Students were challenged to design a solution and then to experimentally test it. They optimized storage of blood, built a device to measure rat respiration, tracked stages of the rat estrus cycle and designed equipment to identify parameters that alter compliance of myometrium, and invented a rat heart bypass device. As a result, students used what they learned in other disciplines: biology, chemistry, physics, and calculus. They practiced interdisciplinary communication with teamwork to develop something unique with minimal constraints. Importantly, a common misconception was identified: students replicated experiments to get better at the experiment, and not to account for and measure variability, as taught in statistics. When people looked at various solutions, examined how well each worked, and decided how to explain the cross‐cultural and social value, their thought processes simulated performance in a real‐life work environment much better than traditional physiology lab courses. Clearly, physiology will still be poised to advance society if students are asked to solve real‐world problems.Support or Funding InformationA portion of this research is supported by the National Science Foundation under grant #1346567 for Advancing Competencies in Experimentation ‐ Biology (ACE‐Bio).
Challenges With Initial Implementation of an Intelligent Formative Assessment System
Authors: Wilson Eric , Kibble Jonathan D , Bellew Christine , Hernandez Caridad , Castiglioni Analia , Khan Asra , Kamin Carol , Riordan Anne , Dauner Shila , Lorens Dale , Gangopadhyaya Ananya , Rajagopal Nimmi , Gaglani Shiv , Haynes Ryan , Lineberry Matthew 
Published: November 2023

With a grant from the National Board of Medical Examiners' Stemmler Fund, the University of Illinois at Chicago (UIC) and University of Central Florida (UCF) have introduced an intelligent formative assessment system (www.Osmosis.org) into the preclinical phase of their MD curricula. This web‐browser based and mobile application presents students with individualized regimens of study questions that aim to leverage the testing effect, spaced repetition and the mixed‐practice effect to aid long term retention. In the first semester of use, 90 of 120 UCF students tried to use the system answering an average of 136 items per individual though subsequent use of the system has continually decreased. We performed two initial focus groups with first year medical students to learn about the strengths and weaknesses of the IFAS and what factors have affected students' decisions about what study aids to adopt. Groups of 4–5 students gave informed consent and the discussions were audio taped for transcription and thematic analysis. A preliminary coding of the audio files suggests that student decisions about what study aids to use in medical school are strongly affected by advice from upperclassmen in the early part of the first year. Near‐peer advice appears to have high face validity and is readily accepted. The data also suggested that concerns for lack of time and demand for efficiency weigh most heavily on student decisions about what tools to use. The data suggest that high quality orientation is needed when introducing new technology, with widespread consultation in the learning community, including faculty and upperclassmen. New applications must be highly intuitive and easy to use for successful adoption.Support or Funding InformationNational Board of Medical Examiners' Stemmler Fund
The use of a case study from pop culture improves student test scores and evaluations in a cardiovascular physiology class
Authors: Berg Ronan 
Published: November 2023

BackgroundAccording to Zehr's ‘middle ground hypothesis’, the use of case studies from pop culture provides students with a basis for discovery learning by providing familiar and comfortable mental landscape where various scientific principles can be explored (Zehr, 2014). In the present study, I sought to examine the effects of this approach on student learning of cardiovascular physiology.MethodDuring a 5‐week course on cardiovascular physiology for 2nd‐year medical students, I used a scene from Terminator 2: Judgement Day (1991), where the fictional character Miles Dyson suffers multiple fatal gunshot wounds, to teach the cardiovascular effects of severe hemorrhage in two classes (intervention group; n = 50), while a conventional patient case study on severe hemorrhage was used to teach the same physiological principles in a third class (control group; n = 28). At the end of the term, the students filled out an evaluation form, and then underwent a 10‐minute multiple choice test on the related core curriculum in cardiovascular physiology.ResultsThe test scores were significantly higher in the intervention than in the control group (Figure 1). The two groups rated their own skills in physiology similarly (NS), while the intervention group rated the quality of the teaching in physiology higher than the control group (p < 0.05). The majority of the students in the intervention group acknowledged that the use elements from pop culture made the teaching more fun, and enhanced both their understanding of the physiological principles taught, while also motivating them to participate more during class; however, less than half of the students found that the approach led to more self‐study (Figure 2).ConclusionAlthough the use of a narrative from the Terminator franchise did not improve student's perception of their own skills in physiology, they rated this teaching approach higher than conventional teaching, and it did improve their test scores in the relevant core curriculum at the end of term. In accordance with Zehr's ‘middle ground’ hypothesis, my findings thus suggest that the use of case studies from pop culture in the physiology classroom improves student learning.Support or Funding InformationNone
Comparing Femur Cross‐sectional Morphology in Young Outbred Mice Following Daily Exposure to Muscle‐, Impact‐, or Combined Loading of the Hind Limb Skeleton
Authors: Smolinsky Amanda N , Middleton Kevin M 
Published: November 2023

Limb bones are exposed to a multitude of intrinsic and extrinsic loading forces which they must resist in order to prevent fracture and maintain function. Bone is a plastic tissue which can adapt to encountered loads by increasing cortical thickness in areas of high strain and resorbing cortex in areas of low strain, thereby optimizing strength, weight, and metabolic requirements. While exercises such as running and jumping are known to induce changes in the cross‐sectional dimensions of limb bones, the relative contributions of muscular contractions and extrinsic ground reaction forces (GRF) in altering bone morphology are not fully understood. We compared femur gross and cross‐sectional morphology in mice exposed to four loading environments that differ in the source of forces imposed on the skeleton: swimming (muscle‐dominated), impact loading via falling (GRF‐dominated), running (combined muscle and GRF characteristic of natural locomotion), and sedentary controls. Four‐week‐old male Hsd:ICR mice were randomly assigned to treatment groups and completed loading exercises daily for 20 days. Mice were injected twice with fluorochrome labels during the final week of treatment to allow measurement of mineral apposition rates and regionalization. Undecalcified femoral mid‐diaphyseal sections were photographed using light and fluorescent microscopy and analyzed for cross‐sectional properties and mineral apposition patterns. We found that the falling impact group had the greatest distal femoral width, but the swim group had the greatest width at the mid‐diaphysis. The jump impact group demonstrated significantly greater cross‐sectional area and moments of inertia than controls, indicating increased resistance to torsion and bending compared to other loading regimes. Examination of mineral apposition patterns showed that mineral apposition was greatest posterolaterally in all groups, with additional medial or posterior cortical drift characterizing each loading treatment. These results indicate regional sensitivity of the growth and morphology of the femur to muscle‐ and GRF‐derived loads and suggest that impact loading induces the growth of stronger bones than other forms of exercise. Future analyses will use 3D geometric morphometrics to examine overall shape differences in femur, tibia, and pelvis following loading treatment.Support or Funding InformationUniversity of Missouri School of Medicine
Low‐impact climbing exercise during growth enhances skeletal muscle function
Authors: Organ Jason , Biro Kelly , Vickery Benjamin , Monnin Gregory , Waning David 
Published: November 2023

High‐impact exercise (running/jumping) improves musculoskeletal mechanical properties such as bone strength and muscle maximum contractile force, but is also associated with higher incidence of skeletal fracture. Thus, it is not an appropriate treatment for patients with an elevated risk of fracture, such as osteogenesis imperfecta (brittle bone disease). Mechanical loads originating from multiple, off‐axis directions, however, have elicited anabolic skeletal responses even when magnitudes are relatively low. This represents a potential alternative to high‐impact exercise for improving musculoskeletal mechanical properties. The effects on muscle function, however, are not well characterized. To examine the potential effects on skeletal muscle, we raised female C57BL/6 mice to 4 months of age in custom enclosures that prevent (parking deck) or require (fine‐wire) manual and pedal grasping while balancing above narrow wire substrates, and compared them to mice raised in standard mouse cages (shoebox). At sacrifice, we measured soleus and extensor digitorum longus weight, specific forces, and half relaxation times across a range of physiological stimulation frequencies in an ex vivo whole muscle contractility assay. Muscle weights and relaxation times were not significantly different between experimental groups. Specific forces of the soleus muscles were significantly higher in the fine‐wire group than either of the other groups, especially at middle to high stimulation frequencies. Extensor digitorum properties were not different among groups. This suggests that muscle function was enhanced by low‐impact exercise, although the response was inconsistent between muscles dominated by faster myosin heavy chain isoforms (extensor digitorum longus) and slower myosin heavy chain isoforms (soleus).Support or Funding InformationShowalter Research Trust, IUPUI Biomechanics and Biomaterials Research Center
Anatomical descriptions of developing hypoglossal motor neurons in the green frog, Lithobates clamitans, and bullfrog, Lithobates catesbeiana, through metamorphosis
Authors: Anderson Curt W , Carroll Andrew J 
Published: November 2023

During metamorphosis anuran amphibians undergo dramatic changes in the central nervous system to facilitate the transition from an aquatic to a semi‐terrestrial lifestyle. Dramatic remodeling of organs as well as the development of new structures takes place in a very short period of time. For example, these tadpoles undergo the process of metamorphosis where they transform from a herbivore dependent on a feeding apparatus consisting of scraping mouth parts that efficiently harvest algae for dietary consumption to a carnivorous diet where the animal actively captures prey with a protrusible tongue and jaw musculature. Prior to metamorphosis, tadpole larvae do not have a developed tongue. During metamorphosis the structures of the tongue are not developed, for instance the anlage of the tongue does not appear until stage 10 and is not fully developed until stage 24. Muscular contraction of the adult tongue in Ranid frogs is primarily directed by hypoglossal nuclei in adult models. Although the circuitry and descriptions of the hypoglossal complex has been described in adult models, the dramatic development during metamorphosis of these neurons has been not studied completely. Retrograde labeling and proliferation of cell development studies of hypoglossal motor nuclei in the brainstem of developing Lithobates catesbeiana and Lithobates clamitans larvae have revealed morphological changes including peripheral nerve disconnection from the brainstem in T/K stages XV‐adult. Additional morphological differences including size and distribution between larvae and adults are substantial. A nearly 1/3 increase in average cell number and a corresponding 2/3 loss in average cell area (μm2) was observed. Significant alterations in the differentiation, morphology and distribution of the motor neurons were also observed. Cellular proliferation was characterized in the ventral horn of the brainstem with mitotic activity from stage XV‐until metamorphic climax. There is a distinct period of time during development where peripheral connections from the spinal cord are lost and the cells undergo significant restructuring.Support or Funding InformationIdaho INBRE NIH Grant #P20 RR0116454
Potus Flavus: Linking Tail Integumentary Function and Microanatomical Structure
Authors: Ruiz Palacios Saul A. , Plochocki Jeffrey H. , Rodriguez‐Sosa Jose R. , Hall Margaret I. 
Published: November 2023

Animal anatomy is an important area of study in relationship to function and structural differences across species. Unlike human anatomy this is an area which is heavily understudied and presents many questions still unanswered. The Kinkajou or Potos flavus is a rainforest mammal that is native to regions of Central and South America. As the only member of the Potus genus and with nocturnal habits, little is known about the microanatomy of the kinkajou. In this study we utilize basic tissue staining techniques and light microscopy to evaluate and quantify the microanatomy of the kinkajou's prehensile tail as it relates to functionality. Our experimental design utilized tissue sections from a young adult at the cranial, middle and caudal regions of the tail with dorsal and ventral sections of the trunk acting as control groups. Using a routine Hematoxylin and Eosin stain we measured the tissue for thickness in the epidermis and dermis, dermal ridge number and size as well as hair follicle numbers. Our results indicate negative correlations between epidermis thickness and dermal ridges, dermal ridge number and diameter as well as hair follicle to dermal ridge height. In conclusion, the ventral side of the kinkajou tail displayed a thinner epidermis with a highly concentrated dermal ridge count while the dorsal side of the tail was follicle dense with few dermal ridges. These findings support the functionality of the prehensile tail through increased sensitivity and tactile acuity for a necessarily increased grip on the ventral side of the tail.Support or Funding InformationSupport provided by Midwestern University.
Adult female human bony pelvis obstetric morphology differences with respect to age are not due to selection
Authors: Auerbach Benjamin M. 
Published: November 2023

Recent studies call into question whether human pelvic morphology reflects evolutionary tradeoffs suggested in the obstetrical dilemma, in which responses to competing selection pressures for obstetrical sufficiency and locomotor efficiency shape the pelvis. Nevertheless, dimensions of the true pelvis likely evolved in response to selection pressures for parturition of large fetuses. Thus, females with narrow bony birth canals may have encountered difficulties in childbirth in the past, even though recent research shows that fetal size and maternal size covary, lessening the possible selection pressure that might result from mismatches in fetal and maternal size. Moreover, the dimensions of the birth canal do not scale isometrically among humans, so groups with smaller body size have proportionally larger dimensions in the true pelvis than groups with larger body sizes.In studies of skeletal remains from multiple archaeological sites, age‐at‐death in females is correlated with dimensions of the true pelvis, with younger females exhibiting narrower dimensions, a pattern not observed in males. These studies proposed selective pressures as leading to this discrepancy, though continued growth of the pelvis in adulthood could also be a cause for the pattern. Here, I examine whether selection motivated the relationship between female age‐at‐death and true pelvis dimensions.Fourteen linear pelvic dimensions were measured from the skeletons of 327 adults (188 females, 139 males) associated with six late Holocene Native American archaeological sites. Individuals were aged into two categories: “young” (approximately 25 years old and younger), and “not young” (approximately older than 25 years). Measurements were mean‐scaled within sex‐and‐ age groups. If selection were acting against young females with narrow dimensions, the variance for younger females should be greater than within not young females. Comparisons show no differences in variance between age groups. Thus, there is no evidence to support selection as driving the differences in pelvic dimensions between age groups. Further analyses, based on studies of integration and age‐group comparisons, indicates that the pelvis continues to grow throughout early adulthood. This growth is not driven by any single region of the pelvis, but rather appears to be the result of continued remodeling of the entire true pelvis. These results caution against making assumptions about the roles of evolutionary forces in shaping morphological variation.Support or Funding InformationFunding provided by the National Science Foundation, BCS Division Collaborative Research Grant #0962752.
Spinal process shape and vertebral immobility in hominoids and Hox9 mutant mice
Authors: Machnicki Allison L , Hrycaj Steven M , Wellik Deneen M , Reno Philip L 
Published: November 2023

The nature of the human/chimpanzee last common ancestor is fundamental for understanding the evolution of human bipedalism. A particular focus is the conformation of its spine. There are multiple mechanisms for stiffening the spine of apes, including reduction of the number of lumbar vertebrae, the level of the transitional vertebra where the articular facets change from coronal to sagittal orientation, and the shape and angulation of the spinous processes. There is debate regarding whether these features are homologous or homoplastic, and thus whether bipedalism evolved from a short stiff back like great apes or a longer lumbar column more similar to monkeys and Miocene hominoids. Genetic modification of Hox9 in mice results in the correlated modification of spinous process shape and placement of the transitional vertebra independent of alternation in lumbar number, mimicking evolutionary changes observed in hominoids. This indicates that the articular facets and spinous processes may be associated developmental modules.To test this hypothesis, we examined this change in spinous process across the thoracolumbar transition in hominoids and compared it to microCT scans of Hox9 modified mice. We used a NextEngine3D scanner to create surface scans of the lower thoracic and lumbar vertebrae of humans, gorillas, chimpanzees, orangutans, and gibbons in order to assess the angulation, orientation, and shape change of the spinous process relative to the position of the transitional vertebra and lumbar number. Humans and gibbons have a similar change in spinous process orientation and shape at the level of the transitional vertebra. Chimpanzees, gorillas, and orangutans each differ in their pattern of spinous process transition across the thoracolumbar boundary suggesting that mechanisms for lumbar stiffening in these taxa may be independently derived.Support or Funding InformationThis material is based upon work supported by the National Science Foundation under Grant No. DGE1255832, the Wenner Gren Foundation, and by the Pennsylvania State University Hill Fellowship.