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SARS-CoV-2 continues to upend human life by posing novel threats related to disease spread and mutations. Current models for the disease burden of SARS-CoV-2 consider the aggregate nature of the virus without differentiating between the potency of its multiple strains. Hence, there is a need to create a fundamental modeling framework for multi-strain viruses that considers the competing viral pathogenic pathways. Alongside the consideration that other viral pathogens may coexist, there is also a need for a generalizable modeling framework to account for multiple epidemics (i.e., multi-demics) scenarios, such as influenza and COVID-19 occurring simultaneously. We present a fundamental network thermodynamics approach for assessing, determining, and predicting viral outbreak severity, which extends well-known standard epidemiological models. In particular, we use historical data from New York City's 2011–2019 influenza seasons and SARS-CoV-2 spread to identify the model parameters. In our model-based analysis, we employ a standard susceptible–infected–recovered (SIR) model with pertinent generalizations to account for multi-strain and multi-demics scenarios. We show that the reaction affinities underpinning the formation processes of our model can be used to categorize the severity of infectious or deceased populations. The spontaneity of occurrence captured by the change in Gibbs free energy of reaction ( ∆ G ) in the system suggests the stability of forward occurring population transfers. The magnitude of ∆ G is used to examine past influenza outbreaks and infer epidemiological factors, such as mortality and case burden. This method can be extrapolated for wide-ranging utility in computational epidemiology. The risk of overlapping multi-demics seasons between influenza and SARS-CoV-2 will persist as a significant threat in forthcoming years. Further, the possibility of mutating strains requires novel ways of analyzing the network of competing infection pathways. The approach outlined in this study allows for the identification of new stable strains and the potential increase in disease burden from a complex systems perspective, thereby allowing for a potential response to the significant question: are the effects of a multi-demic greater than the sum of its individual viral epidemics? [ABSTRACT FROM AUTHOR]

This article presents ideas and narratives of an experiment on the concept of energy developed for an honors seminar on energy and a mechanics course. We argue that energy is an idea best taught in an interdisciplinary manner. While most physics courses explore ideas such as mechanical energy and conservation of energy, it is imperative that a more practical view of energy as fuel be addressed since this has particular relevance to our students' future. We believe energy cannot be discussed without talking about entropy and that a proper introduction to energy can only be made by simultaneously discussing the idea of entropy. In this article, we present one lab activity related to carbon emissions from bicycling, designed to help elucidate this idea through the use of conceptual metaphors and embodied learning. The learning goals of the activity were to encourage students to understand that energy and entropy are intricately related and to have students gain a deeper understanding of the concepts by considering and discussing ways in which they apply to different contexts. We discuss the rationale, implementation, and outcomes of the activity. [ABSTRACT FROM AUTHOR]

This paper describes the development and implementation of course modules intended to encourage creative thinking in an undergraduate general education mathematics course. The modules were designed to address the characteristics of creativity outlined in the literature through explorations of mathematics relevant to non-mathematics majors. A general description of the modules, as well as specifics about two lessons is provided. Student work, including journal entries, surveys, and class assignments, provide evidence that this intentional focus on creativity in mathematics challenged students' conceptions about mathematics, allowed them to reconsider the mathematics familiar to them in new ways, and engaged them in meaningful collaborations. Interviews of instructors revealed that they, too, engaged in creative processes as they planned the course and thought about innovative ways to engage students with mathematics. The course modules have been shared with other faculty teaching the course and will eventually be adapted for use in other mathematics courses, including those for STEM majors. Implications and future avenues for implementation and research are discussed. [ABSTRACT FROM AUTHOR]

The article focuses on several fundamental questions that have occupied scholars of metaphysics, but also those in the physical and natural sciences for several centuries. Topics include examines artificial intelligence that provide a scientific definition of life and primacy of the laws of thermodynamics in science that is articulated by the Nobel laureate, astronomer, Sir Arthur Eddington.

In this article, we describe a project that was developed for an introductory-level physics course. The aim of the project was to encourage the creative process in science, as science is seldom mentioned in discussions about creativity. We sought to engage students in the creative process by posing a collective challenge to the class. The challenge involved designing a sustainable means by which to produce short films on the theme of sustainability. Through the project, students experienced project-based learning, open-ended questions, and independent research. The overall project went beyond the physics classroom, however; it linked physics to visual arts, music, theater, and English. In this article, we present the physics project and provide the context of the overarching project. We describe the motivation for the project and the implementation and outcomes of the project, report on impact on students, and suggest ways in which creativity can be encouraged in all science classes. [ABSTRACT FROM AUTHOR]

This article focuses on the philosophy of creativity and its enhancement through an undergraduate research experience. In this paper we offer suggestions for infusing the undergraduate mathematics and science curriculum with research experiences as a way of fostering creativity in our students. We refer to the termresearchbroadly, offering suggestions to accommodate students from various backgrounds and with different goals. We posit that creativity is a necessary component of scientific thinking, producing students that are motivated, passionate, skilled, adaptable, and responsible. Research experiences at the undergraduate level instill a deep sense of personalized education and learning that can make the entire university experience extremely pleasurable and of lasting value. [ABSTRACT FROM PUBLISHER]

Based on the results of a survey of the science and mathematics students at our university, we observed that students do not consider mathematics and science to be creative endeavors, though the traditional artistic disciplines rank high in this regard. To address this problem in perception, the authors used photography as a means to encourage students to find the deep-rooted connections between science and mathematics and the arts. The photography project was used in a formal classroom setting as well as an outside activity, i.e. in a more informal setting. In this article, we describe the project and its outcomes. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we study the unsteady motion of an inhomogeneous incompressible viscous fluid, where the viscosity varies spatially according to various models. We study the Stokes-type flow for these types of fluids where in the first case the flow between two parallel plates is examined with one of the plates oscillating and in the second case when the flow is caused by a pulsatile pressure gradient. A general argument establishes the existence of oscillatory solutions to our problem. Exact solutions are obtained in terms of some special functions and comparisons are made with the cases of constant viscosity and the slow flow regimes. [Copyright &y& Elsevier]

Abstract: In this paper, we explain some well known experimental observations in fluid solid interaction from a thermodynamic perspective. In particular we use the extremum of the rate of entropy production to establish the stability of specific patterns observed in single and multiparticle sedimentation in an infinite fluid and the sedimentation of spheres in the presence of walls. While these phenomena have been explained numerically, there is no known rigorous theoretical argument to establish the stability of the observed configurations. We provide a very convincing theoretical basis using entropy based arguments that are considered by several scientists as the underlying theme of nature, life and evolution. In the absence of many rigorous examples for the entropy production principle, our paper advances this argument and lends it much credibility. In addition to looking at the rate of entropy production, we also put forth a very plausible heuristic argument based on the thermal gradients in the systems being studied, which could be the underlying causal principle for many known patterns in nature. [Copyright &y& Elsevier]

Abstract: In this paper, we study the unsteady motion of inhomogeneous incompressible viscous fluids. We present the results corresponding to Stokes'' second problem and for the flow between two parallel plates where one is oscillating. [Copyright &y& Elsevier]

Abstract: We study the steady terminal orientation of a fore-aft symmetric body as it settles in a viscous fluid. An optimal principle for the settling behavior is discussed based upon entropy production in the system, both in the Stokes limit and the case of near equilibrium states when inertial effects emerge. We show that in the Stokes limit, the entropy production in the system is zero allowing any possible terminal orientation while in the presence of inertia, the particle assumes a horizontal position which coincides with the state of maximum entropy production. Our results are seen to agree well with experimental observations. [Copyright &y& Elsevier]

In this paper we hypothesize that education, especially at the scale of curriculum, should be treated as a complex system composed of different ideas and concepts which are inherently connected. Therefore, the task of a good teacher lies in elucidating these connections and helping students make their own connections. Such a pedagogy allows students to personalize learning and strive to be 'creative' and make meaning out of old ideas. The novel contribution of this work lies in the mathematical approach we undertake to verify our hypothesis. We take the example of a precalculus course curriculum to make our case. We treat textbooks as exemplars of a specific pedagogy and map several texts into networks of isolated (nodes) and interconnected concepts (edges) thereby permitting computations of metrics which have much relevance to the education theorists, teachers and all others involved in the field of education. We contend that network metrics such as average path length, clustering coefficient and degree distribution provide valuable insights to teachers and students about the kind of pedagogy which encourages good teaching and learning. [ABSTRACT FROM AUTHOR]

Abstract: In this article, we provide a brief review of some generalizations of the second grade fluid model. We discuss certain similarities between these fluids and fluids of higher grades, while also describing certain limitations of these models. The new models that we put forth are based upon some interesting experimental results which suggest that not only can normal stress coefficients depend upon the shear rate, but that this dependency is in fact not the same rate as that of shear viscosity variation with shear rate. We then discuss some steady flows of these generalized second grade fluid models. [Copyright &y& Elsevier]

Abstract: We study the flow due to natural convection of a non-Newtonian fluid, modeled as a generalized second grade fluid, between two vertical parallel walls. The flow results from the two walls being held at different temperatures. The viscosity of the fluid is taken to be a function of temperature according to Reynolds’ exponential law. We solve for the dimensionless velocity and temperature profiles and study their dependence upon certain material parameters. [Copyright &y& Elsevier]

Abstract: We study the slow motion of rigid bodies of arbitrary shape sedimenting in a quiescent viscoelastic liquid under the action of gravity. The liquid is modeled by the full second order fluid equations with arbitrary material parameters . We show existence of steady state solutions for small Weissenberg numbers and zero Reynolds numbers and apply our equations to study the steady state orientations of symmetric bodies sedimenting in viscoelastic fluids. [Copyright &y& Elsevier]

We study the steady translational fall of a homogeneous body of revolution around an axis a, with fore-and-aft symmetry, in a second-order liquid at nonzero Reynolds (Re) and Weissenberg (We) numbers. We show that, at first order in these parameters, only two orientations are allowed, namely, those with a either parallel or perpendicular to the direction of the gravity g. In both cases the translational velocity is parallel to g. The stability of the orientations can be described in terms of a critical value E[SUBc] for the elasticity number E = We/Re, where E[SUBc] depends only on the geometric properties of the body, such as size or shape, and on the quantity (ψ[SUBl] + ψ[SUB2])/ψ[SUB1], where ψ[SUBl] and ψ[SUB2] are the first and second normal stress coefficients. These results are then applied to the case when the body is a prolate spheroid. Our analysis shows, in particular, that there is no tilt-angle phenomenon at first order in Re and We. [ABSTRACT FROM AUTHOR]

The place of living organisms in the natural world is a nearly perennial question in philosophy and the sciences; how can inanimate matter yield animate beings? A dominant answer for several centuries has been to treat organisms as sophisticated machines, studying them with the mechanistic physics and chemistry that have given rise to technology and complex machines. Since the early 20th century, many scholars have sought instead to naturalize biology through thermodynamics, recognizing the precarious far-from-equilibrium state of organisms. Erwin Bauer was an early progenitor of this perspective with ambitions of "general laws for the movement of living matter". In addition to taking a thermodynamic perspective, Bauer recognized that organisms are fundamentally behaving systems, and that explaining the physics of life requires explaining the origins of intentionality, adaptability, and self-regulation. Bauer, like some later scholars, seems to advocate for a "new physics", one that extends beyond mechanics and classical thermodynamic, one that would be inclusive of living systems. In this historical review piece, we explore some of Bauer's ideas and explain how similar concepts have been explored in modern non-equilibrium thermodynamics and dissipative structure theory. Non-living dissipative structures display end-directedness, self-maintenance, and adaptability analogous to organisms. These findings also point to an alternative framework for the life sciences, that treats organisms not as machines but as sophisticated dissipative structures. We evaluate the differences between mechanistic and thermodynamic perspectives on life, and what each theory entails for understanding the behavior of organisms. [ABSTRACT FROM AUTHOR]

The goal of the Creativity in Mathematics and Science project, funded by the National Science Foundation's [NSF's] Improving Undergraduate STEM Educa- tion program, is to reconsider how we teach mathematics at the collegiate level. Over the last three years, we have developed interdisciplinary modules that seek to encourage students, including non-STEM majors, to see mathematics in un- expected places, make connections to their own interests and disciplines, and explore creativity in mathematics. Relying on traits of creativity such as the abil- ity to connect ideas, be inquisitive, question norms, and have exibility [1], we encouraged students to participate and understand mathematics in unconven- tional ways. The scheduling of a professional juggling company's performance at our on-campus theater inspired us to create a module connecting mathematics and juggling for both a general education mathematics course and a mechanics course. We drew from research on the mathematics of juggling [2, 3] to de- velop a module that encouraged students to explore the patterns, notations, and mathematical elements of juggling in a variety of ways. Their final projects, rep- resenting further explorations, were displayed in our theater's lobby and featured interactive displays and demonstrations. In this paper we describe our experi- ences developing and implementing this juggling module, students' experiences with the modules, and their development of final projects. [ABSTRACT FROM AUTHOR]

The physical origin of behaviour in biological organisms is distinct from those of non-living systems in one significant way: organisms exhibit intentionality or goal-directed behaviour. How may we understand and explain this important aspect in physical terms, grounded in laws of physics and chemistry? In this article, we discuss recent experimental and theoretical progress in this area and future prospects of this line of thought. The physical basis for our investigation is thermodynamics, though other branches of physics and chemistry have an important role. This article is part of the theme issue 'Thermodynamics 2.0: Bridging the natural and social sciences (Part 1)'. [ABSTRACT FROM AUTHOR]

Assessment is an issue that is central to the lives of educators and students alike. At all levels, from programmatic to course-specific, instructors strive to assess in a way that accurately measures achievement or progress relative to one's goals. This paper reports on students' experiences with alternative assessments in our undergraduate mathematics course for non-STEM (Science, Technology, Engineering and Mathematics) majors. The course, Creative Thinking in Mathematics, designed to fulfil the university's general education requirement for mathematics, was recently revised and renamed to highlight the role of creativity in mathematics. In the course, students engage in mathematics using creative approaches and consider how these approaches connect to other disciplines, their career aspirations, and important mathematical discoveries throughout history. This shift in course emphasis necessitated revisions to assessments in ways that mirrored the course's instructional approach. This article describes the alternative assessments, outlines the research study, and reports on the results relative to students' experiences with these assessments, both prior to and during the course, highlighting a need for instructors to reconsider traditional assessments. [ABSTRACT FROM AUTHOR]

Abstract.: The terminal orientation of a rigid body in a moving fluid is an example of a dissipative system, out of thermodynamic equilibrium and therefore a perfect testing ground for the validity of the maximum entropy production principle (MaxEP). Thus far, dynamical equations alone have been employed in studying the equilibrium states in fluid-solid interactions, but these are far too complex and become analytically intractable when inertial effects come into play. At that stage, our only recourse is to rely on numerical techniques which can be computationally expensive. In our past work, we have shown that the MaxEP is a reliable tool to help predict orientational equilibrium states of highly symmetric bodies such as cylinders, spheroids and toroidal bodies. The MaxEP correctly helps choose the stable equilibrium in these cases when the system is slightly out of thermodynamic equilibrium. In the current paper, we expand our analysis to examine i) bodies with fewer symmetries than previously reported, for instance, a half-ellipse and ii) when the system is far from thermodynamic equilibrium. Using two-dimensional numerical studies at Reynolds numbers ranging between 0 and 14, we examine the validity of the MaxEP. Our analysis of flow past a half-ellipse shows that overall the MaxEP is a good predictor of the equilibrium states but, in the special case of the half-ellipse with aspect ratio much greater than unity, the MaxEP is replaced by the Min-MaxEP, at higher Reynolds numbers when inertial effects come into play. Experiments in sedimentation tanks and with hinged bodies in a flow tank confirm these calculations. Graphical abstract: [ABSTRACT FROM AUTHOR]

This paper investigates the mechanics of clearance of an embedded particle in a lubrication layer of viscoelastic fluid. We show theoretically that in a slider bearing domain containing a viscoelastic fluid, the oscillating shearing motion of a wall aids in transporting away any embedded particle towards the moving boundary. The impact of geometry and material properties of the fluid layer are explored by coupling theoretical and numerical methods. Our approach suggests a possible mechanism by which the human eye could clear out any debris beneath the eyelid, under responsive blinking. Our simplified analysis brings to bear interesting approaches from physics and engineering upon a very complex biological problem and could provide essential clues about the physiological design of the tear film. [ABSTRACT FROM AUTHOR]

In this short paper, we consider the possibility of transporting the biomass material by pipeline as slurry. We assume the suspension can be modeled as a non-homogenous viscous fluid whose viscosity is a function of space and time. We solve the steady fully developed flow of this complex fluid between two long horizontal plates subject to the no-slip condition. Three different correlations are proposed for the viscosity and results are presented for the velocity profile and the volumetric flow rate. A feasibility study is proposed on the basis of these analytical findings. [ABSTRACT FROM AUTHOR]

Self-templating propagation of protein aggregate conformations is increasingly becoming a significant factor in many neurological diseases. In Alzheimer disease (AD), intrinsically disordered amyloid-β (Aβ) peptides undergo aggregation that is sensitive to environmental conditions. High-molecular weight aggregates of Aβ that form insoluble fibrils are deposited as senile plaques in AD brains. However, low-molecular weight aggregates called soluble oligomers are known to be the primary toxic agents responsible for neuronal dysfunction. The aggregation process is highly stochastic involving both homotypic (Aβ-Aβ) and heterotypic (Aβ with interacting partners) interactions. Two of the important members of interacting partners are membrane lipids and surfactants, to which Aβ shows a perpetual association. Aβ–membrane interactions have been widely investigated for more than two decades, and this research has provided a wealth of information. Although this has greatly enriched our understanding, the objective of this review is to consolidate the information from the literature that collectively showcases the unique phenomenon of lipid-mediated Aβ oligomer generation, which has largely remained inconspicuous. This is especially important because Aβ aggregate “strains” are increasingly becoming relevant in light of the correlations between the structure of aggregates and AD phenotypes. Here, we will focus on aspects of Aβ-lipid interactions specifically from the context of how lipid modulation generates a wide variety of biophysically and biochemically distinct oligomer sub-types. This, we believe, will refocus our thinking on the influence of lipids and open new approaches in delineating the mechanisms of AD pathogenesis. This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy. [ABSTRACT FROM AUTHOR]

Students in a beginning level undergraduate classical mechanics course engaged in collaborative inquiry through the Windwalker Project. The aim of this project was for students to create a free-standing movable structure as a way of testing and applying their understanding of the conceptual and theoretical elements of the course. This article reports on the impact of this project-based learning environment on the students' understanding of physics and describes the instructor's actions that supported their progress. Students described the benefits and challenges of this learning environment as they related to their experiences with uncertainty, efforts to overcome obstacles through collaboration, and understanding of scientific research. The instructor was able to facilitate the groups' work while supporting them with instruction on the underlying physics principles. [ABSTRACT FROM AUTHOR]

Blood grouping discrepancy in patients with hematological disorders can occur due to red cell sensitization following transfusion, transplantation, and pregnancy or pre-analytical errors. Prompt initiation of root cause analysis is vital to avoid complications of wrong blood transfusion. We present an unusual case of Rh mismatched grouping report of 24 year old female thalassemia patient being managed in our hospital since 2015. Her current type and screen were observed as O Rh D negative with negative antibody screen while the historical blood group was O Rh D positive. The pre-analytical errors were ruled out and blood grouping performed from fresh sample also demonstrated as O Rh D negative despite antigen enhancement techniques and had no recent transfusion history. We sought to reason out the possibilities for discordant Rh grouping report, historical and present group through "Funnel based problem solving 5 WHY analysis" approach. The review of the past clinical history revealed that the patient had undergone Rh mismatch bone marrow transplant (Rh D positive donor and Rh D negative recipient) at 5 years of age which soon resulted in graft failure. Yet, she continued to receive Rh D positive blood thereafter with no development of anti-D which explains the historical blood group. Recently the patient was started on thalidomide, the Hb F inducer drug, which helped in maintaining her hemoglobin level between 9 and 10 g/dl without transfusion support for two months. This allowed unmasking of native Rh D negative blood and the review of clinical history played a significant role in resolution of grouping discrepancy. [ABSTRACT FROM AUTHOR]

Fluids provide the optimal setting to explore natural patterns far from thermodynamic equilibrium. Experiments suggest that randomly dispersed particles on a liquid surface tend to aggregate on the surface of liquid over time, and the process is enhanced by an increase in the temperature of the liquid. We show that the agglomeration radii increases monotonically with temperature up until the point where all particles in the system form a single, large aggregate. The aggregation dynamics is related to changes in the material properties of the liquid including its viscosity and surface tension as well as the convection driven flow generated on the fluid surface. In this article we compare our experimental observations with analytical asymptotic results. The analytical arguments are seen to agree well with the experimental observations. [ABSTRACT FROM AUTHOR]

We discuss the equilibrium configurations of a fiber clamped to a spherical body and immersed in a flow ranging between 0 and 50 cm/s. Experimental and numerical results are presented and the effects of flow speed and positioning of the fiber upon the equilibrium configuration are investigated. Our investigations reveal that the orientation of the fiber and its length has a significant impact upon its bending and drag experienced by the sphere-fiber system. We note that the longer fibers (i) bend significantly more than the shorter ones and (ii) display oscillatory or flapping motion at much lower flow speeds than their shorter counterparts. The simulations also reveal that the drag on the fiber is noticeably effected by the size of the basal body. Drag exponents (or Vogel exponents) are also computed and seen to deviate slightly from previous results. [ABSTRACT FROM AUTHOR]

Background: In all amyloid diseases, protein aggregates have been implicated fully or partly, in the etiology of the disease. Due to their significance in human pathologies, there have been unprecedented efforts towards physiochemical understanding of aggregation and amyloid formation over the last two decades. An important relation from which hydrodynamic radii of the aggregate is routinely measured is the classic Stokes-Einstein equation. Here, we report a modification in the classical Stokes-Einstein equation using a mixture theory approach, in order to accommodate the changes in viscosity of the solvent due to the changes in solute size and shape, to implement a more realistic model for Aβ aggregation involved in Alzheimer's disease. Specifically, we have focused on validating this model in protofibrill lateral association reactions along the aggregation pathway, which has been experimentally well characterized. Results: The modified Stokes-Einstein equation incorporates an effective viscosity for the mixture consisting of the macromolecules and solvent where the lateral association reaction occurs. This effective viscosity is modeled as a function of the volume fractions of the different species of molecules. The novelty of our model is that in addition to the volume fractions, it incorporates previously published reports on the dimensions of the protofibrils and their aggregates to formulate a more appropriate shape rather than mere spheres. The net result is that the diffusion coefficient which is inversely proportional to the viscosity of the system is now dependent on the concentration of the different molecules as well as their proper shapes. Comparison with experiments for variations in diffusion coefficients over time reveals very similar trends. Conclusions: We argue that the standard Stokes-Einstein's equation is insufficient to understand the temporal variations in diffusion when trying to understand the aggregation behavior of Aβ42 proteins. Our modifications also involve inclusion of improved shape factors of molecules and more appropriate viscosities. The modification we are reporting is not only useful in Aβ aggregation but also will be important for accurate measurements in all protein aggregation systems. [ABSTRACT FROM AUTHOR]

Abstract: We establish the existence and the asymptotic properties of a path of minimum travel time for a line of particles starting upstream of a sphere or cylinder in potential flow. A connection is made between this brachistochrone path and Darwin''s proposition which relates the added mass with the drift volume dragged by a body moving an infinite distance in the fluid. We compute an asymptotic correction to the drift volume for finite distances and show how the brachistochrone path is connected to the reflux volume. We present accurate numerical calculations for the brachistochrone position, point of zero horizontal Lagrangian displacement, reflux and partial drift volumes. These calculations are seen to agree well with the asymptotic predictions even for moderate values of the parameters. In the small Reynolds number regimes, we show that while for the case of Stokes flow past a sphere no brachistochrones exist at finite distances from the sphere, the Oseen correction is sufficient to restore such least-time trajectories. Lastly, the application to a sphere falling in a stratified fluid is discussed using the new drift volume correction formula. [Copyright &y& Elsevier]