Modulation of Hypoglossal Motoneurons by Nitric Oxide

Obstructive sleep apnea (OSA)- the occurrence of repetitive episodes of airway obstruction during sleep- is considered a major health problem affecting up to 9% of adults in the United States (Parish & Somers, 2004). The hypoglossal motor nucleus (HMN) controls genioglossus muscle tone and is critically important for maintaining airway patency; loss of excitatory input to the HMN during sleep results in disfacilitation of hypoglossal motoneurons, increased airway resistance and contributes to the development of OSA (Horner R. L., 2007). However, a fundamental question of sleep medicine that remains unresolved is what mechanisms help maintain airway patency during sleep? A potential source of sleep-activated compensatory drive is nitric oxide released from cholinergic terminals in the HMN (Pose et al. 2005; Vincent & Kimura, 1992). Here we show that NO functions as an excitatory transmitter in the HMN by a cGMP-dependent inhibition of a background TASK-like conductance and an S-nitrosylation-dependent activation of the instantaneous but not the time-dependent component of the hyperpolarization-activated current (Ih) generated by hyperpolarization-activated cyclic nucleotide gated (HCN) channels. These results suggest that sleep-induced nitrergic innervation of the HMN helps compensate for respiratory motoneuron disfacilitation and disruption of NO/cGMP signaling may contribute to the etiology of OSA. Although a causal link between disruption of NO/cGMP signaling and occurrence of OSA has yet to be established, it is well known that patients with metabolic syndrome have high levels of uric acid- a potent NO scavenger- and, perhaps consequently, are at much higher risk of developing OSA (Mota, 2010)

Session D, 2016 Third Place: The Response of American Toads (Anaxyrus americanus) to The Urine of Distressed Conspecifics

The American toad (Anaxyrus americanus) utilizes alarm pheromones to communicate most prominently in the larval stages of life (Chivers et al 1999). This is also a developing subject of study on adult A. americanus and other anurans (Woodley 2010). This method of communication between adult A. americanus, in regards to danger, was the objective of our study. We collected A. americanus and coaxed them into urinating in a jar with toilet paper and then put them in the experimental tank (one side had toilet paper with toad urine, and the other side had toilet paper with tap water). A different toad was then measured, sexed, and placed in a container with a hole on top and allowed two minutes to acclimate in the tank. The container was then lifted, and the toad’s behavior and distance traveled was recorded during a two-minute period. After running a two proportion t-test, the results showed that A. americanus did not prefer water over the urine of a distressed conspecific. A Chi-square test was performed which showed that there was not a significant difference in the distance traveled away from the urine between large and small A. americanus. Another Chi-square test was done and showed that there was no difference in the distance traveled away from the urine between male and female A. americanus. The results of our study do not allow us to draw any significant conclusions in regards to the presence of alarm pheromones in the urine of adult A. americanus

The power to change the equation: mathematics teacher learning reimagined

In this series of provocations, we distill a series of arguments that we have heard from interviews with math researchers, teachers, teacher leaders, and publishers. We’ve chosen six of the most interesting lines of thinking to publish in advance of the Future of Math Teacher Learning conference to set the table with a set of ideas that we can debate, build upon, or discard. These provocations are not the “right” way to think about the future of math teacher learning, but they were six arguments that challenged our assumptions, sparked our thinking, and helped us imagine new ways of approaching teacher learning.https://tsl.mit.edu/the-power-to-change-the-equation-mathematics-teacher-learning-reimagined

On polynomial integrals over the orthogonal group

We consider integrals of type $\int_{O_n}u_{11}^{a_1}... u_{1n}^{a_n}u_{21}^{b_1}... u_{2n}^{b_n} du$, with respect to the Haar measure on the orthogonal group. We establish several remarkable invariance properties satisfied by such integrals, by using combinatorial methods. We present as well a general formula for such integrals, as a sum of products of factorials.Comment: 20 page

Red Blood Cell Distribution Width (RDW) Predicts COVID-19 Severity: A Prospective, Observational Study from the Cincinnati SARS-CoV-2 Emergency Department Cohort

Since previous evidence has demonstrated that red blood cell distribution width (RDW) may be a useful prognostic parameter in many critical illnesses and infectious diseases, we investigated the utility of RDW for monitoring patients with coronavirus disease 2019 (COVID-19). The study population consisted of 49 COVID-19 patients, including 16 (32.6%) with severe illness, 12 (24.5%) with severe acute kidney injury (AKI), and 8 (16.3%) requiring renal replacement therapy (RRT). The predictive value of blood tests, performed during emergency department evaluation, was then addressed. A progressive increase of RDW was observed with advancing COVID-19 severity. The area under the curve (AUC) of RDW was 0.73 for predicting severe illness, 0.80 for severe AKI, and 0.83 for RRT, respectively. In multivariate analysis, elevated RDW was associated with 9-fold and 16-fold increased odds of severe COVID-19 and AKI, respectively. The results of this study suggest that RDW should be part of routine laboratory assessment and monitoring of COVID-19

The future of math teacher professional learning

We summarize the results of a field scan that set out to describe the current state of math teacher learning and promising future directions for improving math teaching and learning for all learners, particularly those most underestimated by the education system. We share five key learnings: (1) math teacher learning is in a "steady state," where schools and districts generally use three approaches to support math educators: professional learning communities (PLCs), instructional coaching, and professional learning workshops, (2) researchers have not been able to document a strong link between each of these three approaches and teacher and student learning, with the exception of coaching which shows benefits for teachers but not direct evidence of student learning, (3) comprehensive programs that apply several of these approaches simultaneously with sufficient supports can improve math outcomes for students, but gains often dissipate when supports decline, (4) there are a few "points of light" of innovative new approaches including teacher-led learning innovations, teacher pipeline initiatives, practice-embedded models, and digital clinical simulations, and (5) there are opportunities for new initiatives in math education to pay greater attention to the implications for teacher learning. We discuss important critiques of our report and offer a "call to action" for stakeholders in the field.Published versio

Conditioned spin and charge dynamics of a single electron quantum dot

In this article we describe the incoherent and coherent spin and charge dynamics of a single electron quantum dot. We use a stochastic master equation to model the state of the system, as inferred by an observer with access to only the measurement signal. Measurements obtained during an interval of time contribute, by a past quantum state analysis, to our knowledge about the system at any time $t$ within that interval. Such analysis permits precise estimation of physical parameters, and we propose and test a modification of the classical Baum-Welch parameter re-estimation method to systems driven by both coherent and incoherent processes.Comment: 9 pages, 9 figure

Simulating more equitable discussions: using teacher moments and practice based teacher education in mathematical professional learning

Digital simulations have become an increasingly popular approach to practice-based teacher education. In this paper we report on a professional learning intervention where we used digital clinical simulations to help mathematics teachers’ fluency in facilitating both small group and whole group discussion. Further we discuss implications of digital clinical simulation as a tool that can help mathematics educators develop, practice, and further support their teaching.Accepted manuscrip