ADAM: Analysis of Discrete Models of Biological Systems Using Computer Algebra

Background: Many biological systems are modeled qualitatively with discrete models, such as probabilistic Boolean networks, logical models, Petri nets, and agent-based models, with the goal to gain a better understanding of the system. The computational complexity to analyze the complete dynamics of these models grows exponentially in the number of variables, which impedes working with complex models. Although there exist sophisticated algorithms to determine the dynamics of discrete models, their implementations usually require labor-intensive formatting of the model formulation, and they are oftentimes not accessible to users without programming skills. Efficient analysis methods are needed that are accessible to modelers and easy to use. Method: By converting discrete models into algebraic models, tools from computational algebra can be used to analyze their dynamics. Specifically, we propose a method to identify attractors of a discrete model that is equivalent to solving a system of polynomial equations, a long-studied problem in computer algebra. Results: A method for efficiently identifying attractors, and the web-based tool Analysis of Dynamic Algebraic Models (ADAM), which provides this and other analysis methods for discrete models. ADAM converts several discrete model types automatically into polynomial dynamical systems and analyzes their dynamics using tools from computer algebra. Based on extensive experimentation with both discrete models arising in systems biology and randomly generated networks, we found that the algebraic algorithms presented in this manuscript are fast for systems with the structure maintained by most biological systems, namely sparseness, i.e., while the number of nodes in a biological network may be quite large, each node is affected only by a small number of other nodes, and robustness, i.e., small number of attractors

Marriott International: A Managerial Strategic Audit

A strategic management audit of the public firm, Marriott International, was conducted to identify various factors and managerial strategies that affect Marriott and the global hotels and tourism industry. At the industry level, we conducted a PESTEL and Five Forces analysis, researched the competitive landscape, and assessed the total value potential. We found that the industry experienced a major decline during the COVID-19 pandemic but saw recovery as international travel opened up again. On the company level, we conducted an internal analysis, identified Marriott’s management structure, and identified the firm’s structure and strategies through a SWOT analysis and other relevant research. We assessed the makeup leadership team and Board of Directors and how it has influenced the corporate governance, organizational structures, and controls of the firm. Finally, we analyzed firm structure by looking at Marriott’s business-level, corporate-level, and merger and acquisition strategies. Marriott’s successful mergers and acquisitions have allowed it to grow to be the largest firm in the industry. By employing a broad differentiation strategy with its 30-brand portfolio, it has been able to occupy nearly every segment of the market and maintain its competitive position through its consistent customer service, brand recognition, and customer loyalty through its Marriott Bonvoy program. The Marriott family has maintained influence through their presence on the Board and Executive team, which can be seen through recent voting decisions and compensation

U.S. adult attitudes about biotechnology and risk aversion to gene editing

While attitudes toward genetically modified (GM) foods have a long study history, there is still much to learn about U.S. adults’ attitudes toward gene edited (GnEd) food. We combine results from two online surveys; one study of 1,331 respondents used a randomized approach to compare views between GnEd and GM foods, and the other study of 1,442 respondents used a framing approach to compare GnEd and fungicide as a solution to combat an agricultural fungus. Overall, respondents viewed GnEd and GM similarly. However, the results provide hints that there are more positive attitudes about the capability of GnEd to positively impact the food system. There was no obvious preference for using either GnEd or fungicide to combat an agricultural disease; however, there were some small framing effects. Combined, our results show some differences emerging in the discussion of GnEd versus GM and reduced some of the risk aversion for GnEd compared to fungicide use.Brandon R. McFadden (Department of Agricultural Economics and Agribusiness, University of Arkansas), Joy N. Rumble (Department of Agricultural Communication, Education, and Leadership, The Ohio State University), Kathryn A. Stofer (Department of Agricultural Education and Communication, University of Florida), Kevin M. Folta (Department of Agricultural Education and Communication, University of Florida), Madison Dyment (Horticultural Sciences Department, University of Florida), Corresponding author: Brandon R. McFaddenIncludes bibliographical reference

ADAM: Analysis of Discrete Models of Biological Systems Using Computer Algebra

Abstract Background Many biological systems are modeled qualitatively with discrete models, such as probabilistic Boolean networks, logical models, Petri nets, and agent-based models, to gain a better understanding of them. The computational complexity to analyze the complete dynamics of these models grows exponentially in the number of variables, which impedes working with complex models. There exist software tools to analyze discrete models, but they either lack the algorithmic functionality to analyze complex models deterministically or they are inaccessible to many users as they require understanding the underlying algorithm and implementation, do not have a graphical user interface, or are hard to install. Efficient analysis methods that are accessible to modelers and easy to use are needed. Results We propose a method for efficiently identifying attractors and introduce the web-based tool Analysis of Dynamic Algebraic Models (ADAM), which provides this and other analysis methods for discrete models. ADAM converts several discrete model types automatically into polynomial dynamical systems and analyzes their dynamics using tools from computer algebra. Specifically, we propose a method to identify attractors of a discrete model that is equivalent to solving a system of polynomial equations, a long-studied problem in computer algebra. Based on extensive experimentation with both discrete models arising in systems biology and randomly generated networks, we found that the algebraic algorithms presented in this manuscript are fast for systems with the structure maintained by most biological systems, namely sparseness and robustness. For a large set of published complex discrete models, ADAM identified the attractors in less than one second. Conclusions Discrete modeling techniques are a useful tool for analyzing complex biological systems and there is a need in the biological community for accessible efficient analysis tools. ADAM provides analysis methods based on mathematical algorithms as a web-based tool for several different input formats, and it makes analysis of complex models accessible to a larger community, as it is platform independent as a web-service and does not require understanding of the underlying mathematics

Tribute to Professor Doug Rendleman

A tribute to Professor Doug Rendleman, who served on the faculty of the Washington and Lee University School of Law from 1988 to 2020. Rendleman became Professor of Law, Emeritus in 2020

Dietary carbohydrate restriction improves metabolic syndrome independent of weight loss

BACKGROUNDMetabolic syndrome (MetS) is highly correlated with obesity and cardiovascular risk, but the importance of dietary carbohydrate independent of weight loss in MetS treatment remains controversial. Here, we test the theory that dietary carbohydrate intolerance (i.e., the inability to process carbohydrate in a healthy manner) rather than obesity per se is a fundamental feature of MetS.METHODSIndividuals who were obese with a diagnosis of MetS were fed three 4-week weight-maintenance diets that were low, moderate, and high in carbohydrate. Protein was constant and fat was exchanged isocalorically for carbohydrate across all diets.RESULTSDespite maintaining body mass, low-carbohydrate (LC) intake enhanced fat oxidation and was more effective in reversing MetS, especially high triglycerides, low HDL-C, and the small LDL subclass phenotype. Carbohydrate restriction also improved abnormal fatty acid composition, an emerging MetS feature. Despite containing 2.5 times more saturated fat than the high-carbohydrate diet, an LC diet decreased plasma total saturated fat and palmitoleate and increased arachidonate.CONCLUSIONConsistent with the perspective that MetS is a pathologic state that manifests as dietary carbohydrate intolerance, these results show that compared with eucaloric high-carbohydrate intake, LC/high-fat diets benefit MetS independent of whole-body or fat mass.TRIAL REGISTRATIONClinicalTrials.gov Identifier: NCT02918422.FUNDINGDairy Management Inc. and the Dutch Dairy Association

The Lantern, 2017-2018

On Dissociation • Untouchable • After Rocket Man • The Science Fair • Cardinal Rule at Stephen J. Memorial • Quentin & Sylvie • Cabello • The Get Out • Painting Day • Black, White and Grey • Family Pruning • How to Remove a Stain • Becoming Ourselves • Wonderbread U • Overture • Pescadero • Gross • Stage Fright • Lucky Daddy • Sarah • Rumble • Silvermine • The Green Iguana • A Poem for Ghost Children • A Poem for Lost Boys • Mother • Drop of Grease • Don\u27t Wanna be White • I • Amelia Earhart Disappeared Into My Vagina: An Ode to Cunts, Menstrual Cups and All Things Woman • Suburban Summer • Nightmares and Dreams Induced by My Mother • Teacups, Skins, etc. • Three Thoughts About My Bedroom • Dear Siri • 2 Queens (Beyonce in Reference to Sonia Sanchez) • Voyeurs • In Front of the Bathroom Mirror • To a Rose • Howl • Mice • Mirror • Language Accordion Volcano Mouth • Lucky Woman • Butterscotch • To Persephone • Wolf • Notes Never Passed • Topple • Bust • Kyoto • Identity • Sunflower • Tornabuoni Bubbles • Olympia • Decayed Hall • Perspectivehttps://digitalcommons.ursinus.edu/lantern/1186/thumbnail.jp