Pathway by which Vagus Nerve Stimulation of B Fibers Affects Heart Rate

Heart failure (HF) affects over 5 million adults in the United States. Many HF patients have a high resting heart rate, which is correlated with a high mortality rate. In recent years, vagus nerve stimulation (VNS) has become an increasingly researched therapy to reduce the resting heart rate of HF patients. However, current dosage given during VNS is increased incrementally at the doctor’s office until side effects present themselves in a patient. In addition, the means by which the therapy works is not completely understood. To better understand the therapy’s mechanisms, the right cervical vagus nerve of several Long Evans rats was exposed and cuffed. Autonomous Nerve Control (ANC) was utilized to activate various percentages of B Fibers, which have been found to be the most influential fiber on heart rate. After the first round of stimulation, a vagotomy was performed superior to the stimulation cuff on the nerve, and the stimulation was repeated. Initial experimentation was performed to confirm the electronics set-up and the surgical approach as well as ensure that a decrease in heart rate could be achieved with stimulation. Further experimentation is still needed to fully characterize the relationship between VNS and heart rate both before and after vagotomy. Knowing the pathway by which VNS affects heart rate can give further insight into how VNS treatment works. Additionally, further research needs to be performed to characterize the interaction between VNS therapy and drugs routinely prescribed to HF patients

Generation of Molecular Complexity from Cyclooctatetraene: Preparation of Aminobicyclo[5.1.0]octitols

A series of eight stereoisomeric N-(tetrahydroxy bicyclo-[5.1.0]oct-2S*-yl)phthalimides were prepared in one to four steps from N-(bicyclo[5.1.0]octa-3,5-dien-2-yl)phthalimide (±)-7, which is readily available from cyclooctatetraene (62 % yield). The structural assignments of the stereoisomers were established by 1H NMR spectral data as well as X-ray crystal structures for certain members. The outcomes of several epoxydiol hydrolyses, particularly ring contraction and enlargement, are of note. The isomeric phthalimides as well as the free amines did not exhibit β-glucosidase inhibitory activity at a concentration of less than 100 μM

Systematic Analysis of Real-World Driving Behavior Following Focal Brain Lesions

Many patients with circumscribed brain injuries, such as those caused by stroke or focal trauma, return to driving after a period of acute recovery. These persons often have chronic residual cognitive deficits that may impact on driving safety, but little is known about their driving behavior in the real world. Extant studies tend to rely on driving simulators or controlled on-road drives. These methods of observation are not able to capture the complexities of the typical driving environment, and may not accurately represent a driver’s usual behavior on the road. The current study used a video event-activated data recorder (VEADR) system to observe drivers with focal brain lesions in their normal daily driving environment over a three-month period. In the context of primarily safe driving behavior, we were able to document a number of relatively infrequent and hitherto unobserved high risk behaviors and traffic violations. These findings demonstrate the feasibility and value of sampling real-world driving in neurologic patient populations such as those with focal brain lesions, and highlight the critical importance of evaluating unsafe driving behaviors which may occur with insufficient frequency to be captured by relatively brief simulator or controlled on-road evaluations

Fine-Wire Intramuscular Insertion to the Lumbar Paraspinal Muscles does not Affect Muscle Activation and Performance During High Exertion Spinal Extension Muscle Contractions

Background and Purpose: Low back pain (LBP) is associated with paraspinal muscle dysfunctions. A method to study the deep lumbar paraspinal muscle activation is with intramuscular electromyography (EMG). However, it is currently unknown how paraspinal muscle performance is affected by the invasive intramuscular insertion and the presence of the fine-wire electrode in the muscle. The purpose of this study was to analyze how insertion of fine-wire EMG into lumbar paraspinal muscle affects the lumbar paraspinal muscle fatigue, endurance, activation, and peak extension torque during high exertion spinal extension exercises. Participants: 20 individuals between the ages of 18-40 participated. The participants were healthy with no history of LBP within the last 6 months that required activity modification or medical care. Methods: Data was obtained during 3 separate testing sessions, spaced 5 to 10 days apart. The first session obtained baseline outcome measures without intramuscular insertion (BL), with subsequent sessions utilizing a random order of insertion followed by leaving the intramuscular electrode fine-wire in (WI) or out (WO) of the muscle. Lumbar paraspinal peak extension torque was assessed with isokinetic dynamometry. Lumbar paraspinal endurance was evaluated using the Sorensen test. Paraspinal muscle fatigue was assessed using the rate of change (slope) of the median frequency during the endurance test. Percent of muscle activation was calculated by using the average muscle activation level during the endurance task. Pain and discomfort levels were recorded using the Visual Analog Scale (VAS) at specific times during the test sessions. All outcome measures were compared across the 3 conditions using one-way repeated measures ANOVAs and post-hoc analyses when indicated. Results: Our results showed no significant difference in peak torque (p = 0.196) between the BL, WI, and WO conditions. A significant difference in lumbar paraspinal endurance was found between the 3 conditions (p = 0.025). Post-hoc analysis showed that the muscle endurance in the WO condition was significantly longer than the BL condition (161.30 ± 58.267 sec vs. 142.05 ± 48.159 sec; p = 0.037). Percent of muscle activation during the endurance testing was not significantly different between the 3 conditions (p = 0.120). Pain scores reported during the 3 conditions were minimal (ranged 0-4/10). No pain was reported on the first day of testing (BL). No significant difference in pain scores was found between the WI and WO conditions: during each of the the three MVIC trials, after the MVIC trials, during the Sorensen test, or after the Sorensen test (p = 0.104, p = 0.186, p = 0.214, p = 0.330, p = 0.527, p = 0.481, respectively). Discussion: Our findings suggested that the insertion and presence of fine-wire EMG in the lumbar paraspinal muscles had no significant impact on lumbar paraspinal muscle peak extension torque, activation or fatigue and induced minimal pain. However, the results did suggest that the insertion and subsequent removal of the fine-wire did have an affect on lumbar paraspinal endurance. This study provides empirical evidence to validate the use of fine-wire EMG for studying lumbar paraspinal muscles during activities that require high muscular exertion

Comparing students\u27 solutions to an open-ended problem in an introductory programming course with and without explicit modeling interventions

Engineers must understand how to build, apply, and adapt various types of models in order to be successful. Throughout undergraduate engineering education, modeling is fundamental for many core concepts, though it is rarely explicitly taught. There are many benefits to explicitly teaching modeling, particularly in the first years of an engineering program. The research questions that drove this study are: (1) How do students\u27 solutions to a complex, open-ended problem (both written and coded solutions) develop over the course of multiple submissions? and (2) How do these developments compare across groups of students that did and did not participate in a course centered around modeling?. Students\u27 solutions to an open-ended problem across multiple sections of an introductory programming course were explored. These sections were all divided across two groups: (1) experimental group - these sections discussed and utilized mathematical and computational models explicitly throughout the course, and (2) comparison group - these sections focused on developing algorithms and writing code with a more traditional approach. All sections required students to complete a common open-ended problem that consisted of two versions of the problem (the first version with smaller data set and the other a larger data set). Each version had two submissions - (1) a mathematical model or algorithm (i.e. students\u27 written solution potentially with tables and figures) and (2) a computational model or program (i.e. students\u27 MATLAB code). The students\u27 solutions were graded by student graders after completing two required training sessions that consisted of assessing multiple sample student solutions using the rubrics to ensure consistency across grading. The resulting assessments of students\u27 works based on the rubrics were analyzed to identify patterns students\u27 submissions and comparisons across sections. The results identified differences existing in the mathematical and computational model development between students from the experimental and comparison groups. The students in the experimental group were able to better address the complexity of the problem. Most groups demonstrated similar levels and types of change across the submissions for the other dimensions related to the purpose of model components, addressing the users\u27 anticipated needs, and communicating their solutions. These findings help inform other researchers and instructors how to help students develop mathematical and computational modeling skills, especially in a programming course. This work is part of a larger NSF study about the impact of varying levels of modeling interventions related to different types of models on students\u27 awareness of different types of models and their applications, as well as their ability to apply and develop different types of models

Change in student understanding of modeling during first year engineering courses

All engineers must be able to apply and create models to be effective problem solvers, critical thinkers, and innovative designers. To be more successful in their studies and careers, students need a foundational knowledge about models. An adaptable approach can help students develop their modeling skills across a variety of modeling types, including physical models, mathematical models, logical models, and computational models. Physical models (e.g., prototypes) are the most common type of models that engineering students identify and discuss during the design process. There is a need to explicitly focus on varying types of models, model application, and model development in the engineering curriculum, especially on mathematical and computational models. This NSF project proposes two approaches to creating a holistic modeling environment for learning at two universities. These universities require different levels of revision to the existing first-year engineering courses or programs. The proposed approaches change to a unified language and discussion around modeling with the intent of contextualizing modeling as a fundamental tool within engineering. To evaluate student learning on modeling in engineering, we conducted pre and post surveys across three different first-year engineering courses at these two universities with different student demographics. The comparison between the pre and post surveys highlighted student learning on engineering modeling based on different teaching and curriculum change approaches

The Mother of Chaos and Night: Kant\u27s Metaphilosophical Attack on Indifferentism

Kant positions the Critical philosophy as a response to the crisis of metaphysics - a crisis that is still with us. But his diagnosis of that crisis in terms of a struggle between dogmatism, skepticism, and indifferentism is given short shrift in the secondary literature, despite its promise to help us understand Kant\u27s claim that transcendental philosophy represents a radical alternative to these philosophical modi vivendi. After a consideration of Kant\u27s remarks on what philosophy is in general, I argue that all four of these mutually-exclusive ways of philosophizing are best understood as metaphilosophical stances: ways of conceiving of the ends or aims of philosophy, which collectively determine the legitimate moves in philosophical argumentation, thereby setting the terms of success for such inquiry. I then make these four competing stances explicit, by drawing on Kant\u27s scattered remarks on them and their history. This involves articulating and defending Kant\u27s complex and surprisingly sophisticated relationship to dogmatism and skepticism, and hence a general assessment of Kant\u27s attempts to incorporate these stances\u27 insights, and so subvert their appeal, in the course of developing his transcendental philosophy. Readings of Kant which myopically take him to be focused on bluntly refuting the dogmatist (e.g., Allison), or the skeptic (e.g., Guyer), fall into characteristic errors as a result. Even more importantly, I show that Kant\u27s central target is in fact the much-neglected indifferentist, whose metaphilosophical stance is defined by a denial of the distinctness and autonomy of philosophy, in a way antithetical to Kant\u27s attempt to ground his philosophical activity on the fact of human agency. Indifferentism has numerous adherents, though naturally not under that name, both in Kant\u27s day (e.g., the so-called Popularphilosophen) and in our own (e.g., the Wittgenstein of On Certainty). Reading Kant against these thinkers sharply clarifies his aims and methods in the Critical philosophy, in a way that the predominant anti-dogmatic and anti-skeptical readings fail to do. Kant\u27s assault on indifferentism centrally employs a set of arguments designed to put us in a position to rationally endorse our high-order normative principles without risk of (indifferentistically) ascribing that endorsement either to passive uptake from the wider culture, or to the oracular dictates of common sense. Thus, it is only by means of Kant\u27s distinctive transcendental proofs that can we invoke the authority of reason in philosophy without making one of two fatal errors: making reason utterly transcendent, which produces skepticism; or casting reason as wholly immanent, which yields dogmatism. Taken together, Kant\u27s metaphilosophical views promise a revitalization of transcendental philosophy for our contemporary age

Magnetic Field Strength Effects on Nucleosynthesis from Neutron Star Merger Outflows

Magnetohydrodynamic turbulence drives the central engine of post-merger remnants, potentially powering both a nucleosynthetically active disk wind and the relativistic jet behind a short gamma ray burst. We explore the impact of the magnetic field on this engine by simulating three post-merger black hole accretion disks using general relativistic magnetohydrodynamics with Monte Carlo neutrino transport, in each case varying the initial magnetic field strength. We find increasing ejecta masses associated with increasing magnetic field strength. We find that a fairly robust main r -process pattern is produced in all three cases, scaled by the ejected mass. Changing the initial magnetic field strength has a considerable effect on the geometry of the outflow and hints at complex central engine dynamics influencing lanthanide outflows. We find that actinide production is especially sensitive to magnetic field strength, with overall actinide mass fraction calculated at 1 Gyr post-merger increasing by more than a factor of six with a tenfold increase in magnetic field strength. This hints at a possible connection to the variability in actinide enhancements exhibited by metal poor, r -process-enhanced stars

The End is Not the Injury: Posttraumatic Growth After Sport Injuries

This quantitative study explored whether serious injuries in varsity high school or collegiate athletes could produce Posttraumatic Growth (PTG). The impact of injury (season- or career-ending) and an athlete’s highest level of competition played (varsity high school or collegiate) were examined on five elements on the 2-item Posttraumatic Growth Inventory (PTGI): (1) relating to others, (2) new possibilities, (3) personal strength, (4) spiritual change, and (5) appreciation of life. This study provides evidence that sport level does not impact an athlete’s ability to produce PTG and bring awareness to trauma and the role PTG can have in an athlete’s life