From the Ground Up: Building a Student-Centered Digital Scholarship Program

In Summer 2017, Bucknell’s Digital Scholarship Student Research Fellows (DSSRF) program welcomed its inaugural cohort. DSSRF is a librarian-led program which introduces students to digital scholarship tools and methodologies, and equips them with the skills necessary to undertake an independent, digitally-based research project. In this presentation, co-facilitators Courtney Paddick and Carrie Pirmann will discuss how the idea of DSSRF was brought to fruition, lessons learned from the first year of the program, and the importance of collaboration (both on campus and interinstitutional) in facilitating a meaningful learning experience for students. Rennie Heza \u2718, Justin Guzman ‘19, and Minglu Xu ‘20, members of the first DSSRF cohort, will talk about their experiences in the program and what drew them to digital scholarship

Substrate utilization during exercise performed with and without glucose ingestion in female and male endurance trained athletes

Compared to males, females oxidize proportionately more fat and less carbohydrate during endurance exercise performed in the fasted state. This study was designed to test the hypothesis that there may also be gender differences in exogenous carbohydrate (CHOexo) oxidation during exercise. Healthy, young males (n = 7) and females (n = 7) each completed 2 exercise trials (90 min cycle ergometry at 60% VO[sub2peak]), 1 week apart. Females were eumenorrheic and were tested in the midfollicular phase of their menstrual cycle. Subjects drank intermittently either 8% CHOexo (1 g glucose &sdot; kg &sdot; h[sup-1]) enriched with U-13C glucose or an artificially sweetened placebo during the trial. Whole-body substrate oxidation was determined from PER, urinary urea excretion, and the ratio of 13C:12C in expired gas during the final 60 min of exercise. During the placebo trial, fat oxidation was higher in females than in males (0.42 &plusmn; 0.07 vs. 0.32 &plusmn; 0.09 g &sdot; min[sup-1] . kg LBM[sup-1] x 10[sup-2]) at 30 min of exercise (p &lt; .05). When averaged over the final 60 min of exercise, the relative proportions of fat, total carbohydrate, and protein were similar between groups. During CHOexo ingestion, both the ratio of 13C: 12C in expired gas (p &lt; .05) and the proportion of energy derived from CHOexo relative to LBM (p &lt; .05) were higher in females compared to males at 75- and 90-min exercise. When averaged over the final 60 min of exercise, the percentage of CHOexo to the total energy contribution tended to be higher in females (14.3 + 1.2%) than in males (11.2 &plusmn; 1.2%; p = .09). The reduction in endogenous CHO oxidation with CHOexo intake was also greater in females (12.9 &plusmn; 3.1%) than in males (5.1 &plusmn; 2.0%; p = .05). Compared to males, females may oxidize a greater relative proportion of CHOexo during endurance exercise which, in turn, may spare more endogenous fuel. Based on these observations, ingested carbohydrate may be a particularly beneficial source of fuel during endurance exercise for females.<br /

Designing Digital Materials with Volumetric Gradients

Next-generation engineering designs could be digitally conceived as vast constellations of material dots in space and physically fabricated with advanced Additive Manufacturing (AM) technologies. AM is already transforming how we create physical objects across a wide range of manufacturing industries. However, recent advances in multi-material AM make it possible to envision a form of three-dimensional pointillism, whereby complex structures are designed and assembled on a micron-by-micron basis through the precise placement of different material “dots” within three-dimensional space. In line with traditional pointillism techniques, different compositions of many small dots would collectively give rise to higher-level properties such as colour and geometry, but also physical properties such as: topology, stiffness, flexibility, and transparency. This paper first describes exciting challenges and opportunities associated with designing multi-material objects as constellations of material dots, then outlines initial experiments which explore data-driven volumetric gradients to design and fabricate physical objects using advanced PolyJet technologies

Striking Denervation of Neuromuscular Junctions without Lumbar Motoneuron Loss in Geriatric Mouse Muscle

Reasons for the progressive age-related loss of skeletal muscle mass and function, namely sarcopenia, are complex. Few studies describe sarcopenia in mice, although this species is the mammalian model of choice for genetic intervention and development of pharmaceutical interventions for muscle degeneration. One factor, important to sarcopenia-associated neuromuscular change, is myofibre denervation. Here we describe the morphology of the neuromuscular compartment in young (3 month) compared to geriatric (29 month) old female C57Bl/6J mice. There was no significant difference in the size or number of motoneuron cell bodies at the lumbar level (L1–L5) of the spinal cord at 3 and 29 months. However, in geriatric mice, there was a striking increase (by ∼2.5 fold) in the percentage of fully denervated neuromuscular junctions (NMJs) and associated deterioration of Schwann cells in fast extensor digitorum longus (EDL), but not in slow soleus muscles. There were also distinct changes in myofibre composition of lower limb muscles (tibialis anterior (TA) and soleus) with a shift at 29 months to a faster phenotype in fast TA muscle and to a slower phenotype in slow soleus muscle. Overall, we demonstrate complex changes at the NMJ and muscle levels in geriatric mice that occur despite the maintenance of motoneuron cell bodies in the spinal cord. The challenge is to identify which components of the neuromuscular system are primarily responsible for the marked changes within the NMJ and muscle, in order to selectively target future interventions to reduce sarcopenia

Evolving concepts on the age-related changes in “muscle quality”

The deterioration of skeletal muscle with advancing age has long been anecdotally recognized and has been of scientific interest for more than 150 years. Over the past several decades, the scientific and medical communities have recognized that skeletal muscle dysfunction (e.g., muscle weakness, poor muscle coordination, etc.) is a debilitating and life-threatening condition in the elderly. For example, the age-associated loss of muscle strength is highly associated with both mortality and physical disability. It is well-accepted that voluntary muscle force production is not solely dependent upon muscle size, but rather results from a combination of neurologic and skeletal muscle factors, and that biologic properties of both of these systems are altered with aging. Accordingly, numerous scientists and clinicians have used the term “muscle quality” to describe the relationship between voluntary muscle strength and muscle size. In this review article, we discuss the age-associated changes in the neuromuscular system—starting at the level of the brain and proceeding down to the subcellular level of individual muscle fibers—that are potentially influential in the etiology of dynapenia (age-related loss of muscle strength and power)

Clinical validity assessment of genes frequently tested on intellectual disability/autism sequencing panels.

[en] PURPOSE: Neurodevelopmental disorders (NDDs), such as intellectual disability (ID) and autism spectrum disorder (ASD), exhibit genetic and phenotypic heterogeneity, making them difficult to differentiate without a molecular diagnosis. The Clinical Genome Resource Intellectual Disability/Autism Gene Curation Expert Panel (GCEP) uses systematic curation to distinguish ID/ASD genes that are appropriate for clinical testing (ie, with substantial evidence supporting their relationship to disease) from those that are not. METHODS: Using the Clinical Genome Resource gene-disease validity curation framework, the ID/Autism GCEP classified genes frequently included on clinical ID/ASD testing panels as Definitive, Strong, Moderate, Limited, Disputed, Refuted, or No Known Disease Relationship. RESULTS: As of September 2021, 156 gene-disease pairs have been evaluated. Although most (75%) were determined to have definitive roles in NDDs, 22 (14%) genes evaluated had either Limited or Disputed evidence. Such genes are currently not recommended for use in clinical testing owing to the limited ability to assess the effect of identified variants. CONCLUSION: Our understanding of gene-disease relationships evolves over time; new relationships are discovered and previously-held conclusions may be questioned. Without periodic re-examination, inaccurate gene-disease claims may be perpetuated. The ID/Autism GCEP will continue to evaluate these claims to improve diagnosis and clinical care for NDDs

Memory Influences Visual Cognition across Multiple Functional States of Interactive Cortical Dynamics

No embargo requiredMemory supports a wide range of abilities from categorical perception to goal-directed behavior, such as decision-making and episodic recognition. Memory activates fast and surprisingly accurately and even when information is ambiguous or impoverished (i.e., showing object constancy). This paper proposes the multiple-state interactive (MUSI) account of object cognition that attempts to explain how sensory stimulation activates memory across multiple functional states of neural dynamics, including automatic and strategic mental simulation mechanisms that can ground cognition in modal information processing. A key novel postulate of this account is ‘multiple-function regional activity’: The same neuronal population can contribute to multiple brain states, depending upon the dominant set of inputs at that time. In state 1, the initial fast bottom-up pass through posterior neocortex happens between 95 ms and ~200 ms, with knowledge supporting categorical perception by 120 ms. In state 2, starting around 200 ms, a sustained state of iterative activation of object-sensitive cortex involves bottom-up, recurrent, and feedback interactions with frontoparietal cortex. This supports higher cognitive functions associated with decision-making even under ambiguous or impoverished conditions, phenomenological consciousness, and automatic mental simulation. In the latest state so far identified, state M, starting around 300 to 500 ms, large-scale cortical network interactions, including between multiple networks (e.g., control, salience, and especially default mode), further modulate posterior cortex. This supports elaborated cognition based on earlier processing, including episodic memory, strategic mental simulation, decision evaluation, creativity, and access consciousness. Convergent evidence is reviewed from cognitive neuroscience of object cognition, decision-making, memory, and mental imagery that support this account and define the brain regions and time course of these brain dynamics

Substrate utilization during exercise performed with and without glucose ingestion in female an male endurance-trained athletes

Test de l'hypothèse selon laquelle il pourrait y avoir des différences liées au sexe dans l'oxygénation du glucose exogène pendant un exercice d'endurance. Etude sur sept femmes et sept hommes

Adaptive materials:utilising additive manufactured scaffolds to control self-organising material aggregation

Extending existing additive manufacturing (AM) capabilities by incorporating self-organising materials (crystal growth) into a system has the potential to create physical structures, which can adapt and tune material properties. We investigate self-organising structures that can respond to different conditions by adapting their physical properties over time. This opens up new possibilities for various design and engineering domains (structural components, furniture design). Initial experiments with the electrolysis of seawater enable the development of these structures. This technology allows a multi-material system sensitive to altering environmental conditions. Material build-up on various cathode types is analysed. The results reveal different material properties are created by altering the environment conditions (i.e. electrical current) in which the crystals grow. We find that turbulence is required within the system to create adaptive tuneable materials. In addition, the physical properties of the cathode scaffold have significant impact in controlling material properties, resolution and the systems dynamic properties