Moments of Askey-Wilson polynomials

New formulas for the nth moment of the Askey-Wilson polynomials are given. These are derived using analytic techniques, and by considering three combinatorial models for the moments: Motzkin paths, matchings, and staircase tableaux. A related positivity theorem is given and another one is conjectured.Comment: 23 page

IRE1 sulfenylation by reactive oxygen species coordinates cellular stress signaling

Maintenance of cellular homeostasis is a fundamental aspect of stress-responsive signal transduction pathways. Specific signaling pathways are often considered, and certainly most often studied, in the context of responses to a specific endogenous or environmental stressor, but there are also fundamental questions that remain regarding how information about stress pathways with potentially overlapping inputs and/or outputs is optimally integrated and transduced by the cellular circuitry. In the current issue of Molecular Cell, Hourihan et al. (2016), combining molecular genetic and biochemical analysis in Caenorhabditis elegans and in mammalian cell systems, identify a mechanism by which IRE1, a principal regulator of the endoplasmic reticulum (ER) Unfolded Protein Response (UPR) (Walter and Ron, 2011), also regulates a response to reactive oxygen species (ROS). Signaling through IRE1 to promote ER homeostasis and the response to oxidative stress appears to be mutually exclusive—that is, signaling one response turns off the other, and vice versa

Developing Methods of Processing and Analyzing Genetic Data to Examine Tiger Salamander Population Structure

Professor Heather Waye and her colleagues conducted a pilot study in 2014 to measure genetic diversity and dispersal pattern in a population of tiger salamanders in west-central Minnesota. The ultimate goal of this research was to analyze the genetic differences between tiger salamander larvae captured in breeding ponds within Pepperton Waterfowl Production Area to understand the population structure and movement patterns. They expected that ponds closer to each other would have more similar genetic information, and that genetic differences between ponds would increase with geographic distance. However, the initial analysis using standard techniques failed to uncover useful patterns in the data. Reorganization of the data and other quantitative approaches are needed to discover any significant patterns in this sample. In my research, I attempted a different modeling method to determine whether re-manipulating samples will uncover hidden patterns of genetic variation. In order to investigate this process, I learned how to install and utilize a software pipeline called Stacks which uses a standard UNIX- like environment operating system called Ubuntu. This software pipeline is a new methodological approach that we are using to build ‘loci’, fixed positions of genetic markers on chromosomes, from short-read sequences to map the relationship between individual tiger salamanders. We hope this technique that interrogates DNA fragments will provide the potential genetic differences between individuals in the sample. My results improve understanding of how to use advanced statistical and computational methods tailored to complex problems with real-world data.https://digitalcommons.morris.umn.edu/urs_2018/1007/thumbnail.jp

Cooperative Network Formation between Swarm Robots

Swarm robot technology could be used in future daily applications. It does not require a lot of manpower once it is deployed into the field compared to doing large scale tasks manually done by humans. However, the downside of using swarm robots is that when the number of agents grow the communication between the swarms will also gradually get more complicated. Besides that, when moving large number of agents in a swarm towards completing a specific task together will also be a challenge due to the monitoring of each swarm agent’s location. Lastly, the swarms should be able to reestablish their location with the large swarms if it ever gets lost from the pack. In order to overcome these problems, engineers have been exploring various ways of making robots work together and communicate with each other with different methods and tools. For this project, it will focus more on the type of wireless communication used, ranging from short range Bluetooth to long range Wi-Fi. With the wireless communication established, the swarms should be able to perform multi-hop communication with each agents through different network topologies. Finally, the swarm robots requires a cooperative algorithm in order for it to adapt to various situation in the different environments. When each agent is deployed into outdoor environments, it will have to adapt to the surroundings while maintaining a certain predetermined flight formation and constant communication with each agent and the base station

Says Who?: How News Presentation Format Influences Perceived Believability and the Engagement Level of Social Media Users

We investigate whether the news presentation format affects the believability of a news story and the engagement level of social media users. Specifically, we test to see if highlighting the source delivering the story can nudge the users to think more critically about the truthfulness of the story that they see, and for obscure sources, whether source ratings can affect how the users evaluate the truthfulness. We also test whether the believability can influence the users\u27 engagement level for the presented news post (e.g., read, like, comment, and share). We find that such changes in the news presentation format indeed have significant impacts on how social media users perceive and act on news items