Digital Commons Network^™

Human Microbiome Transfer In The Built Environment Differs Based On Occupants, Objects, And Buildings, Andrew J. Hoisington, Christopher E. Stamper, Katherine L. Bates, Maggie A. Stanislawski, Michael C. Flux, Teodor T. Postolache, Christopher A. Lowry, Lisa A. Brenner

Faculty Publications

Compared to microbiomes on other skin sites, the bacterial microbiome of the human hand has been found to have greater variability across time. To increase understanding regarding the longitudinal transfer of the hand microbiome to objects in the built environment, and vice versa, 22 participants provided skin microbiome samples from their dominant hands, as well as from frequently and infrequently touched objects in their office environments. Additional longitudinal samples from home environments were obtained from a subset of 11 participants. We observed stability of the microbiomes of both the hand and built environments within the office and home settings; however, …

Measuring Radiation Protection: Partners From Across The Nuclear Enterprise Evaluate The Radiation Protection Of Us Army Vehicles, Andrew W. Decker, Robert Prins

Faculty Publications

Recent mounting nuclear threats and postures from adversary nation-states, such as Russia, China, North Korea, and Iran, represent a clear danger to the interests and security of the United States of America and its Allies. To meet these threats, the 2022 Nuclear Posture Review requires the Department of Defense (DoD) to design, develop, and manage a combat-credible U.S. military which, among other prioritizations, is survivable. A survivable force can generate combat power despite adversary attacks. As such, the US Army must prepare today to set the conditions for successful conventional warfare on the nuclear battlefields of tomorrow. Our Army cannot …

Covid-19 Lockdown: Impact On College Students’ Lives, Wendy C. Birmingham, Lori L. Wadsworth, Jane H. Lassetter

Faculty Publications

Objective: In light of COVID-19, leaders issued stay-at-home orders, including closure of higher-education schools. Most students left campus, likely impacting their employment and social network. Leaders are making decisions about opening universities and modality of instruction. Understanding students' psychological, physiological, academic, and financial responses to the shut-down and reopening of campuses can help leaders make informed decisions. Participants: 654 students from a large western university enrolled during the pandemic shutdown. Methods: Students were invited via email to complete an online survey. Results: Students reported stress, depression, loneliness, lack of motivation, difficulty focusing on schoolwork, restless sleep, appetite changes, job loss …

Travels In El Levante Spain: Field Notes And Reflections Summer Of 1999, José A. Rivera Ph.D

Faculty Publications

In the summer of 1999, I traveled to eastern Spain to observe the irrigated landscapes of the region known as huertas. I had recently completed a book about the community acequias of the upper Río Grande and set out to compare them with counterpart systems of Valencia, Murcia, and Lorca. In Valencia the highlights included a session of the fabled Water Court, the Tribunal de las Aguas de Valencia, and a tour of huertas within the urbanized portion of city. In Murcia I visited the office of the Junta de Hacendados and from there made it a point to …

Transmountain Diversion In The Forest Wilderness: Natural History Is Human History, José A. Rivera Ph.D

Faculty Publications

The case study details how an adjudication involving the water rights of Indigenous pueblos downstream of rights held by Hispano irrigators led to a prolonged conflict not with the pueblos but between Cuba valley farmers and the United States Forest Service. It happened that an adjudication decree in federal court mandated the Nacimiento Community Ditch Association to replace its diversion located in a wilderness forest with a modern structure to partition water equitably among all users on the Jémez River. The transmountain diversion, as it was called, took water out of the Jémez basin and dropped it to a canyon …

Adoption Of Model-Based Systems Engineering In Traditional Dod Systems, Patrick E. Assef, Jeremy R. Geiger

Faculty Publications

The transition to digital engineering has become a major objective within the Department of Defense (DoD). One such method is Model-Based Systems Engineering (MBSE), or the use of models to facilitate systems engineering. Most new DoD programs are being built from the ground up using MBSE. However, the question of whether MBSE should be incorporated into existing systems still lingers. Little research currently exists on the efforts required to transition existing systems to MBSE. In this article, the authors measure the effort required to transition an existing system of systems (SoS), which primarily relied on document-centric methods, to MBSE. Time …

Retraction, N. Kinoshita, M. Paul, Y. Kashiv, P. Collon, C. M. Deibel, B. Digiovine, J. P. Greene, C. L. Jiang, S. T. Marley, R. C. Pardo, K. E. Rehm, D. Robertson, R. Scott, C. Schmitt, X. D. Tang, R. Vondrasek, A. Yokoyama

Faculty Publications

No abstract provided.

Slow-Goverance In Smart Cities: An Empirical Study Of Smart Intersection Implementation In Four U. S. College Towns, Brett Frischmann, Madelyn Rose Sanfilippo

Faculty Publications

Cities cannot adopt supposedly smart technological systems and protect human rights without developing appropriate data governance, because technologies are not value-neutral. This paper proposes a deliberative, slow-governance approach to smart tech in cities. Inspired by the Governing Knowledge Commons (GKC) framework and past case studies, we empirically analyse the adoption of smart intersection technologies in four US college towns to evaluate and extend knowledge commons governance approaches to address human rights concerns. Our proposal consists of a set of questions that should guide community decision-making, extending the GKC framework via an incorporation of human-rights impact assessments and a consideration of …

Traffic Lights For Catalysis: Stimuli-Responsive Molecular And Extended Catalytic Systems, Grace C. Thaggard, Johanna Haimeri, Roland A. Fischer Prof. Dr., Kyoung Chul Park, Natalia B. Shustova Prof. Dr.

Faculty Publications

The advances made in the field of stimuli-responsive catalysis during the last five years with a focus on the novel recently-emerged directions and applications have been surveyed. Metal-free catalysts and organometallic complexes, as well as biomimetic systems and extended structures, which display switchable catalytic activity for a variety of organic transformations, are discussed. Light-activated systems comprised of photochromic molecules capable of modulating reaction rate, yield, or enantioselectivity based on geometric and electronic changes associated with photoisomerization are the focus of the detailed discussion. Alternative stimuli, including pH and temperature, which could be applied either alone or in combination with light, …

Trait-Based Assembly Of Arbuscular Mycorrhizal Fungal Communities Determines Soil Carbon Formation And Retention, Caitlyn C. A. Horsch, Pedro M. Antunes, Catherine Fahey, A. Stuart Grandy, Cynthia M. Kallenbach

Faculty Publications

Fungi are crucial for soil organic carbon (SOC) formation, especially for the more persistent mineral-associated organic C (MAOC) pool. Yet, evidence for this often overlooks arbuscular mycorrhizal fungi (AMF) communities and how their composition and traits impact SOC accumulation.

We grew sudangrass with AMF communities representing different traits conserved at the family level: competitors, from the Gigasporaceae family; ruderals, from the Glomeraceae family; or both families combined. We labeled sudangrass with 13C-CO2 to assess AMF contributions to SOC, impacts on SOC priming, and fungal biomass persistence in MAOC.

Single-family AMF communities decreased total SOC by 13.8%, likely due to fungal …

Computational Reverse-Engineering Analysis For Scattering Experiments For Form Factor And Structure Factor Determination (“P(Q) And S(Q) Crease”), Christian M. Heil, Yingzhen Ma, Bhuvnesh Bharti, Arthi Jayaraman

Faculty Publications

In this paper, we present an open-source machine learning (ML)-accelerated computational method to analyze small-angle scattering profiles [I(q) vs q] from concentrated macromolecular solutions to simultaneously obtain the form factor P(q) (e.g., dimensions of a micelle) and the structure factor S(q) (e.g., spatial arrangement of the micelles) without relying on analytical models. This method builds on our recent work on Computational Reverse-Engineering Analysis for Scattering Experiments (CREASE) that has either been applied to obtain P(q) from dilute macromolecular solutions (where S(q) ∼1) or to obtain S(q) from concentrated particle solutions when P(q) is known (e.g., sphere form factor). This paper’s …

Capturing Children Food Exposure Using Wearable Cameras And Deep Learning, Shady Elbassuoni, Hala Ghattas Ph.D., Jalila El Ati, Yorgo Zoughby, Aline Semaan, Christelle Akl, Tarek Trabelsi, Reem Talhouk, Houda Ben Gharbia, Zoulfikar Shmayssani, Aya Mourad

Faculty Publications

Children’s dietary habits are influenced by complex factors within their home, school and neighborhood environments. Identifying such influencers and assessing their effects is traditionally based on self-reported data which can be prone to recall bias. We developed a culturally acceptable machine-learning-based data-collection system to objectively capture school-children’s exposure to food (including food items, food advertisements, and food outlets) in two urban Arab centers: Greater Beirut, in Lebanon, and Greater Tunis, in Tunisia. Our machine-learning-based system consists of 1) a wearable camera that captures continuous footage of children’s environment during a typical school day, 2) a machine learning model that automatically …

Experimental Investigation Of Self-Compacting Concrete With Recycled Concrete Aggregate, Sayed Ahmed, Ayman El-Zohairy, Ahmed S. Eisa, Mohamed Abd El-Aziz Badran Mohamed

Faculty Publications

Due to the depletion of natural aggregates and raw materials for contemporary construction, the construction and demolition waste existing in old concrete structures is an imperative problem. Cutting down on exploiting natural aggregates and reusing construction and demolition waste in the concrete industry are solutions to this problem. This paper investigated the replacement of natural coarse aggregate (NCA) with recycled concrete aggregates (RCA) with different ratios (0%, 50%, 75%, and 100%) in producing self-compacting concrete (SCC). Different components of supplementary cementitious materials (SCMs), such as nano-silica (NS), fly ash (FA), and metakaolin (MK), as well as PVA fibers, were incorporated …

Toward A Simulation Model Complexity Measure, J. Scott Thompson, Douglas D. Hodson, Michael R. Grimaila, Nicholas Hanlon, Richard Dill

Faculty Publications

Is it possible to develop a meaningful measure for the complexity of a simulation model? Algorithmic information theory provides concepts that have been applied in other areas of research for the practical measurement of object complexity. This article offers an overview of the complexity from a variety of perspectives and provides a body of knowledge with respect to the complexity of simulation models. The key terms model detail, resolution, and scope are defined. An important concept from algorithmic information theory, Kolmogorov complexity, and an application of this concept, normalized compression distance, are used to indicate the possibility of measuring changes …

Frontal Polymerizations: From Chemical Perspectives To Macroscopic Properties And Applications, Benjamin A. Suslick, Julie Hemmer, Brecklyn R. Groce, Katherine J. Stawiasz, Philippe H. Geubelle, Giulio Malucelli, Alberto Mariani, Jeffrey S. Moore, John A. Pojman, Nancy R. Sottos

Faculty Publications

The synthesis and processing of most thermoplastics and thermoset polymeric materials rely on energy-inefficient and environmentally burdensome manufacturing methods. Frontal polymerization is an attractive, scalable alternative due to its exploitation of polymerization heat that is generally wasted and unutilized. The only external energy needed for frontal polymerization is an initial thermal (or photo) stimulus that locally ignites the reaction. The subsequent reaction exothermicity provides local heating; the transport of this thermal energy to neighboring monomers in either a liquid or gel-like state results in a self-perpetuating reaction zone that provides fully cured thermosets and thermoplastics. Propagation of this polymerization front …

The Missouri Second Chance Expungement Gap, Colleen Chien

Faculty Publications

No abstract provided.

Simulations Of Morphology Control Of Self-Assembled Amphiphilic Surfactants, Qinyu Zhu, Douglas R. Tree

Faculty Publications

One of the grand challenges of amphiphilic self-assembly is the design of ordered structures whose morphology or shape can be explicitly and dynamically controlled by adjusting the properties of the amphiphiles or their surroundings. Such a capacity would enable researchers to create synthetic systems with functionality that meets or exceeds biological cells, and provide a robust platform for a broad range of engineering applications such as artificial tissues, drug delivery, and separation membranes. Despite significant progress, important fundamental questions remain unanswered, due in part to the limited resolution and the restricted parameter spaces that are readily accessible in experiments. Computational …

Control Education For Societal-Scale Challenges: A Community Roadmap, John Anthony Rossiter, Christos G. Cassandras, João Hespanha, Sebastian Dormido, Luis De La Torre, Gireeja Ranade, Antonio Visioli, John Hedengren, Richard M. Murray, Panos Antsaklis, Francoise Lamnabhi-Lagarrigue, Thomas Parisini

Faculty Publications

This article focuses on extending, disseminating and interpreting the findings of an IEEE Control Systems Society working group looking at the role of control theory and engineering in solving some of the many current and future societal challenges. The findings are interpreted in a manner designed to give focus and direction to both future education and research work in the general control theory and engineering arena, interpreted in the broadest sense. The paper is intended to promote discussion in the community and also provide a useful starting point for colleagues wishing to re-imagine the design and delivery of control-related topics …

Simulations Of Morphology Control Of Self-Assembled Amphiphilic Surfactants, Qinyu Zhu, Douglas R. Tree

Faculty Publications

One of the grand challenges of amphiphilic self-assembly is the design of ordered structures whose morphology or shape can be explicitly and dynamically controlled by adjusting the properties of the amphiphiles or their surroundings. Such a capacity would enable researchers to create synthetic systems with functionality that meets or exceeds biological cells, and provide a robust platform for a broad range of engineering applications such as artificial tissues, drug delivery, and separation membranes. Despite significant progress, important fundamental questions remain unanswered, due in part to the limited resolution and the restricted parameter spaces that are readily accessible in experiments. Computational …

Strengthening The Ti/Tin Interface Against Shear Failure With Al Dopants: A Molecular Dynamics Study, Nisha Dhariwal, Abu Shama Mohammad Miraz, W. J. Meng, Collin D. Wick

Faculty Publications

The impact of Al doping on the stability and shear strength of the Ti/TiN interface was investigated using a newly developed modified embedded atom model interatomic potential. The model was parameterized to the interfacial properties of pure Al, TiAl and AlN binaries as well as TiAlN ternary system. The results of the new model are in reasonably good agreement with those obtained using Density Functional Theory and experimental data from the literature. A Ti/TiN system with a misfit dislocation network present on the Ti layer adjacent to the TiN interface was chosen for doping because of its low interfacial energy. …

A Model For Multi-Input Mechanical Advantage In Origami-Based Mechanisms, Jared Butler, Adam Shrager, Timothy Simpson, Landen Bowen, Mary Frecker, Robert Lang, Eric Wilcox, Paris Von Lockette, Larry L. Howell, Spencer P. Magleby

Faculty Publications

Mechanical advantage is traditionally defined for single input and single-output rigid-body mechanisms. A generalized approach for identifying single-output mechanical advantage for a multiple-input compliant mechanism, such as many origami-based mechanisms, would prove useful in predicting complex mechanism behavior. While origami-based mechanisms are capable of offering unique solutions to engi neering problems, the design process of such mechanisms is complicated by the interaction of motion and forces. This paper presents a model of the mechanical advantage for multi input compliant mechanisms and explores how modifying the parameters of a model affects their behavior. The model is used to predict the force-deflection …

Developable Mechanisms On Regular Cylindrical Surfaces, Jacob R. Greenwood, Spencer P. Magleby, Larry L. Howell

Faculty Publications

Developable mechanisms can provide high functionality and compact stowability. This paper presents engineering models to aid in the design of cylindrical developable mechanisms. These models take into account the added spatial restrictions imposed by the developable surface. Equations are provided for the kinematic analysis of cylindrical developable mechanisms. A new classification for developable mechanisms is also presented (intramobile, extramobile, and transmobile) and two graphical methods are provided for determining this clas sification for single-DOF planar cylindrical developable mechanisms. Characteristics specific to four-bar cylindrical developable mechanisms are also discussed.

Large Deflection Analysis Of General Beams In Contact-Aided Compliant Mechanisms Using Chained Pseudo-Rigid-Body Model, Mohui Jin, Collin Ynchausti, Xianmin Zhang, Zhou Yang, Benliang Zhu, Larry L. Howell

Faculty Publications

The nonlinear analysis and design of contact-aided compliant mechanisms (CCMs) are challenging. This paper presents a nonlinear method for analyzing the deformation of general beams that contact rigid surfaces in CCMs. The large deflection of the general beam is modeled by using the chained pseudo-rigid-body model. A geometry constraint from the contact surface is developed to constrain the beam’s deformed configuration. The contact analysis problem is formulated based on the principle of minimum potential energy and solved using an optimization algorithm. Besides, a novel technique based on the principle of work and energy is proposed calculate the reaction force/moment of …

Delineating The Effects Of Molecular And Colloidal Interactions Of Dissolved Organic Matter On Titania Photocatalysis, Mostafa Maghsoodi, Céline Jacquin, Benoit Teychené, Geoffroy Lesage, Samuel D. Snow

Faculty Publications

In the face of significant challenges to practical applications of photocatalysis for water treatment, recent reports revealed a potential route to overcome a problem posed by dissolved organic matter (DOM). These studies showed that inhibition of photocatalytic processes by DOM is driven largely by competition for active surface sites on TiO2 or other catalysts, and controlling the type of DOM present in solution could significantly mitigate DOM fouling. Whether or not control of solution parameters could achieve the same preventative action is not known. Here, a series of DOM isolates, including humic acid (HA) and transphilic (TPI), hydrophobic (HPO), or …

Student Preferences For Active Learning And Their Beliefs, Experiences, And Knowledge, Tammy Shilling, Jerome Thayer, Anneris Coria-Navia, Heather Ferguson

Faculty Publications

Active teaching methods are believed to facilitate higher-order thinking skills and prepare allied health students for independent clinical decision-making. This quantitative, correlational study aimed to explain the relationships between student preferences for active over traditional methods and their beliefs, the frequency and positiveness of their experiences, and the extent of knowledge they have received regarding active and traditional teaching methods. Two hundred and thirty students completed a 53-item online survey. Students were enrolled in a Doctor of Physical Therapy, Masters in Speech-language Pathology, or Bachelor of Science Nursing program in one of seventeen participating institutions across a ten-state Midwest region. …

Uncovering The Optimal Molecular Characteristics Of Hydrophobe-Containing Polypeptoids To Induce Liposome Or Cell Membrane Fragmentation, Tianyi Yu, Marzhana Omarova, Meng Zhang, Istiak Hossain, Jianqiang Chen, Omead Darvish, Vijay T. John, Donghui Zhang

Faculty Publications

Cellular functions of membrane proteins are strongly coupled to their structures and aggregation states in the cellular membrane. Molecular agents that can induce the fragmentation of lipid membranes are highly sought after as they are potentially useful for extracting membrane proteins in their native lipid environment. Toward this goal, we investigated the fragmentation of synthetic liposome using hydrophobe-containing polypeptoids (HCPs), a class of facially amphiphilic pseudo-peptidic polymers. A series of HCPs with varying chain lengths and hydrophobicities have been designed and synthesized. The effects of polymer molecular characteristics on liposome fragmentation are systemically investigated by a combination of light scattering …

Synthetic Strategies Of Supported Pd-Based Bimetallic Catalysts For Selective Semi-Hydrogenation Of Acetylene: A Review And Perspectives, Xinxiang Cao, Ben W.-L. Jang, Jiaxue Hu, Lei Wang

Faculty Publications

Selective semi-hydrogenation of acetylene is an extremely important reaction from both industrial and theoretical perspectives. Palladium, due to its unique chemical and physical properties, is the most active and currently irreplaceable metal for this reaction in industry, but the poor catalytic selectivity towards ethylene is also its inherent shortcoming. Introducing a secondary metal to tune a geometric and electronic structures of Pd nanoparticles and to create a synergistic effect is the most widely used strategy to effectively improve the overall catalytic performance of Pd-based catalysts. Thus, various supported Pd-based bimetallic catalysts for selective semi-hydrogenation of acetylene have been exploited in …

Ranked Document Retrieval In External Memory, Rahul Shah, Cheng Sheng, Sharma Thankachan, Jeffrey Vitter

Faculty Publications

The ranked (or top-k) document retrieval problem is defined as follows: preprocess a collection {T1,T2,... ,Td} of d strings (called documents) of total length n into a data structure, such that for any given query (P,k), where P is a string (called pattern) of length p ≥ 1 and k ϵ [1,d] is an integer, the identifiers of those k documents that are most relevant to P can be reported, ideally in the sorted order of their relevance. The seminal work by Hon et al. [FOCS 2009 and Journal of the ACM 2014] presented an O(n)-space (in words) data structure …

Rigidly Foldable Thick Origami Using Designed-Offset Linkages, Robert J. Lang, Nathan Brown, Brian Ignaut, Spencer P. Magleby, Larry L. Howell

Faculty Publications

We present new families of thick origami mechanisms that achieve rigid foldability and parallel stacking of panels in the flat-folded state using linkages for some or all of the hinges between panels. A degree-four vertex results in a multi-loop eight-bar spatial mechanism that can be analyzed as separate linkages. The individual linkages are designed so that they introduce offsets perpendicular to the panels that are mutually compatible around each vertex. This family of mechanisms offers the unique combination of a planar unfolded state, parallel-stacked panels in the flat folded state, and kinematic single-degree-of-freedom motion from the flat- unfolded to the …

On The Modeling Of A Contact-Aided Cross-Axis Flexural Pivot, Pietro Bilancia, Giovanni Berselli, Spencer P. Magleby, Larry L. Howell

Faculty Publications

This paper reports the study of a planar Cross-Axis Flexural Pivot (CAFP) comprising an additional contact pair. The proposed device turns useful for applications requiring a revolute joint that behaves differently when deflecting clockwise/anti-clockwise. The presence of the contact pair reduces the free length of one flexures, resulting in a considerable increment of the overall joint stiffness. The pivot behaviour is investigated, for different load cases, via the ChainedBeam-Constraint Model (CBCM), namely an accurate method to be applied in large deflection problems. A framework comprising Matlab and ANSYS is developed for testing the CAFP performances in terms of rotational stiffness, …