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Isolation And Functional Analysis Of A Pancreatic Enzyme In An Introductory Student Lab, Peter J. Lyons Oct 2022

Isolation And Functional Analysis Of A Pancreatic Enzyme In An Introductory Student Lab, Peter J. Lyons

Faculty Publications

Structure and function are correlated at all levels of biology. This topic is typically addressed early in an undergraduate class in general or molecular biology before students have gained much skill or knowledge in molecular biology. However, an understanding of the chemical bonds involved in forming and maintaining the structure of proteins is critical to understanding how enzymes function and how their activity can be regulated. Here, a laboratory activity is described that is suitable for undergraduate biology students. This activity examines the activity of carboxypeptidase A (CPA), an abundant pancreatic enzyme with a rich history in enzymology and structural …


Are Existing Modeling Tools Useful To Evaluate Outcomes In Mangrove Restoration And Rehabilitation Projects? A Minireview, Victor H. Rivera-Monroy, Xiaochen Zhao, Hongqing Wang, Zuo George Xue Oct 2022

Are Existing Modeling Tools Useful To Evaluate Outcomes In Mangrove Restoration And Rehabilitation Projects? A Minireview, Victor H. Rivera-Monroy, Xiaochen Zhao, Hongqing Wang, Zuo George Xue

Faculty Publications

Ecosystem modeling is a critical process for understanding complex systems at spatiotemporal scales needed to conserve, manage, and restore ecosystem services (ESs). Although mangrove wetlands are sources of ESs worth billions of dollars, there is a lack of modeling tools. This is reflected in our lack of understanding of mangroves’ functional and structural attributes. Here, we discuss the “state of the art” of mangrove models used in the planning and monitoring of R/R projects during the last 30 years. The main objectives were to characterize the most frequent modeling approach, their spatiotemporal resolution, and their current utility/application in management decisions. …


Event-Triggered Control Of Robotic Fish With Reduced Communication Rate, Wenyu Zuo, Animesh Chakravarthy, Michael Malisoff, Zheng Chen Oct 2022

Event-Triggered Control Of Robotic Fish With Reduced Communication Rate, Wenyu Zuo, Animesh Chakravarthy, Michael Malisoff, Zheng Chen

Faculty Publications

Underwater robots often need to communicate with external localization sensors. The low bandwidth in such communications is one of the bottlenecks in achieving accurate tracking control. Toward this end, we adopt a novel periodic event-triggered control (PETC) which allows a robotic fish to reduce its communication load in tracking a desired heading angle with position feedback from an external sensor. To design the PETC, a linear state-space model is derived from a nonlinear dynamic model of the robotic fish with a small perturbation assumption. The PETC consists of an observer, state-feedback controller, integrator, event-trigger rule, and predictor. The observer and …


Observational Constraints On Anisotropies For Bouncing Alternatives To Inflation, Ivan Agullo, Javier Olmedo, Edward Wilson-Ewing Oct 2022

Observational Constraints On Anisotropies For Bouncing Alternatives To Inflation, Ivan Agullo, Javier Olmedo, Edward Wilson-Ewing

Faculty Publications

We calculate how primordial anisotropies in the background space-time affect the evolution of cosmological perturbations for bouncing alternatives to inflation, like ekpyrosis and the matter bounce scenario. We find that the leading order effect of anisotropies in the contracting phase of the universe is to induce anisotropies in the cosmic microwave background with a very concrete form: a scale-invariant quadrupolar angular distribution. Sub-leading effects are the generation of higher-order moments in the angular distribution, as well as cross-correlations between scalar and tensor modes. We also find that observational constraints from the cosmic microwave background on the quadrupole moment provide strong …


Academic Program Recommendations For Graduate Degrees In Medical Physics: Aapm Report No. 365 (Revision Of Report No. 197), Jay W. Burmeister, Nathan C. Busse, Ashley J. Cetnar, Rebecca R. Howell, Robert Jeraj, A. Kyle Jones, Steven H. King, Kenneth L. Matthews, Victor J. Montemayor, Wayne Newhauser, Anna E. Rodrigues, Ehsan Samei, Timothy V. Turkington, Mary P. Gronberg, Brian Loughery, Alison R. Roth, Michael C. Joiner, Edward F. Jackson, Paul A. Naine, Leonard H. Kim Oct 2022

Academic Program Recommendations For Graduate Degrees In Medical Physics: Aapm Report No. 365 (Revision Of Report No. 197), Jay W. Burmeister, Nathan C. Busse, Ashley J. Cetnar, Rebecca R. Howell, Robert Jeraj, A. Kyle Jones, Steven H. King, Kenneth L. Matthews, Victor J. Montemayor, Wayne Newhauser, Anna E. Rodrigues, Ehsan Samei, Timothy V. Turkington, Mary P. Gronberg, Brian Loughery, Alison R. Roth, Michael C. Joiner, Edward F. Jackson, Paul A. Naine, Leonard H. Kim

Faculty Publications

No abstract provided.


Kmt-2021-Blg-0171lb And Kmt-2021-Blg-1689lb: Two Microlensing Planets In The Kmtnet High-Cadence Fields With Followup Observations, Hongjing Yang, Weicheng Zang, Andrew Gould, Jennifer C. Yee, Kyu Ha Hwang, Grant Christie, Takahiro Sumi, Jiyuan Zhang, Shude Mao, Michael D. Albrow, Sun Ju Chung, Cheongho Han, Youn Kil Jung, Yoon Hyun Ryu, In Gu Shin, Yossi Shvartzvald, Sang Mok Cha, Dong Jin Kim, Hyoun Woo Kim, Seung Lee Kim, Chung Uk Lee, Dong Joo Lee, Yongseok Lee, Byeong Gon Park, Richard W. Pogge, John Drummond, Dan Maoz, Jennie Mccormick, Tim Natusch, Matthew T. Penny, Wei Zhu, Ian A. Bond, Fumio Abe Oct 2022

Kmt-2021-Blg-0171lb And Kmt-2021-Blg-1689lb: Two Microlensing Planets In The Kmtnet High-Cadence Fields With Followup Observations, Hongjing Yang, Weicheng Zang, Andrew Gould, Jennifer C. Yee, Kyu Ha Hwang, Grant Christie, Takahiro Sumi, Jiyuan Zhang, Shude Mao, Michael D. Albrow, Sun Ju Chung, Cheongho Han, Youn Kil Jung, Yoon Hyun Ryu, In Gu Shin, Yossi Shvartzvald, Sang Mok Cha, Dong Jin Kim, Hyoun Woo Kim, Seung Lee Kim, Chung Uk Lee, Dong Joo Lee, Yongseok Lee, Byeong Gon Park, Richard W. Pogge, John Drummond, Dan Maoz, Jennie Mccormick, Tim Natusch, Matthew T. Penny, Wei Zhu, Ian A. Bond, Fumio Abe

Faculty Publications

Follow-up observations of high-magnification gravitational microlensing events can fully exploit their intrinsic sensitivity to detect extrasolar planets, especially those with small mass ratios. To make followup observations more uniform and efficient, we develop a system, HighMagFinder, to automatically alert possible ongoing high-magnification events based on the real-time data from the Korea Microlensing Telescope Network (KMTNet). We started a new phase of follow-up observations with the help of HighMagFinder in 2021. Here we report the discovery of two planets in high-magnification microlensing events, KMT-2021-BLG-0171 and KMT-2021-BLG-1689, which were identified by the HighMagFinder. We find that both events suffer the 'central-resonant' caustic …


A Covariant Polymerized Scalar Field In Semi-Classical Loop Quantum Gravity, Rodolfo Gambini, Florencia Benítez, Jorge Pullin Oct 2022

A Covariant Polymerized Scalar Field In Semi-Classical Loop Quantum Gravity, Rodolfo Gambini, Florencia Benítez, Jorge Pullin

Faculty Publications

We propose a new polymerization scheme for scalar fields coupled to gravity. It has the advantage of being a (non-bijective) canonical transformation of the fields, and therefore ensures the covariance of the theory. We study it in detail in spherically symmetric situations and compare to other approaches.


Parametrized Topological Complexity Of Collision-Free Motion Planning In The Plane, Daniel C. Cohen, Michael Farber, Shmuel Weinberger Oct 2022

Parametrized Topological Complexity Of Collision-Free Motion Planning In The Plane, Daniel C. Cohen, Michael Farber, Shmuel Weinberger

Faculty Publications

Parametrized motion planning algorithms have high degrees of universality and flexibility, as they are designed to work under a variety of external conditions, which are viewed as parameters and form part of the input of the underlying motion planning problem. In this paper, we analyze the parametrized motion planning problem for the motion of many distinct points in the plane, moving without collision and avoiding multiple distinct obstacles with a priori unknown positions. This complements our prior work Cohen et al. [3] (SIAM J. Appl. Algebra Geom. 5, 229–249), where parametrized motion planning algorithms were introduced, and the obstacle-avoiding collision-free …


Enviromic Prediction Is Useful To Define The Limits Of Climate Adaptation: A Case Study Of Common Bean In Brazil, Alexandre Bryan Heinemann, Germano Costa-Neto, Roberto Fritsche-Neto, David Henriques Da Matta, Igor Kuivjogi Fernandes Oct 2022

Enviromic Prediction Is Useful To Define The Limits Of Climate Adaptation: A Case Study Of Common Bean In Brazil, Alexandre Bryan Heinemann, Germano Costa-Neto, Roberto Fritsche-Neto, David Henriques Da Matta, Igor Kuivjogi Fernandes

Faculty Publications

Ongoing changes in the global environmental conditions foster plant breeding research to develop climate-smart cultivars as fast as possible. Data analytics are essential for achieving this goal, especially the so-called science of enviromics (large-scale environmental characterization of crop growing conditions) that could be used to pinpoint the relevant environment impacts driving the adaptation of a certain specie in a breeding framework. Here we quantified the effects of diverse climate factors on the current adaptation of elite common bean germplasm in Brazil. To capture the non-linearity of those impacts across a wide range of environments, we developed an “enviromic prediction” approach …


On The Spatial Variability Of The Mesoscale Sea Surface Height Wavenumber Spectra In The Atlantic Ocean, Xiaobiao Xu, Eric P. Chassignet, Alan J. Wallcraft, Brian K. Arbic, Maarten C. Buijsman, Miguel Solano Oct 2022

On The Spatial Variability Of The Mesoscale Sea Surface Height Wavenumber Spectra In The Atlantic Ocean, Xiaobiao Xu, Eric P. Chassignet, Alan J. Wallcraft, Brian K. Arbic, Maarten C. Buijsman, Miguel Solano

Faculty Publications

The wavenumber spectral slope of sea surface height (SSH) computed within the mesoscale range (70–250 km) from satellite altimetry exhibits a large spatial variability which, until now, has not been reproduced in numerical ocean models. This study documents the impacts of including internal tides, high-resolution bathymetry, and high-frequency atmospheric variability on the SSH wavenumber spectra in the Atlantic Ocean, using a series of 1/50° North and equatorial Atlantic simulations with a realistic representation of barotropic/baroclinic tides and mesoscale-to-submesoscale variability. The results show that the inclusion of internal tides does increase high frequency SSH variability (with clear peaks near 120 and …


Instrumental Music Education In Rural North Carolina: A Descriptive Study, Melody Causby, Catheryn Shaw Foster Oct 2022

Instrumental Music Education In Rural North Carolina: A Descriptive Study, Melody Causby, Catheryn Shaw Foster

Faculty Publications

The purpose of this study was to investigate secondary instrumental music education in rural North Carolina. This descriptive study investigated the experiences, attitudes, beliefs, and perceptions that rural instrumental music educators (n = 55) held about their schools, students, and communities. Furthermore, the researchers examined how participants defined success for their programs, what challenges and rewards they experienced in their positions, and what skills they considered most important for themselves as teachers.

Results indicate that although rural music educators find the musical aspects of their positions rewarding, they believe that their nonmusical skills related to teaching, such as developing …


Permafrost And Climate Change: Carbon Cycle Feedbacks From The Warming Arctic, Edward A. G. Schuur, Benjamin W. Abbott, Roisin Commane, Jessica G. Ernakovich, Eugenie Euskirchen, Gustaf Hugelius, Guido Grosse, Miriam Jones, Charlie Koven, Victor Leshyk, David Lawrence, Michael M. Loranty, Marguerite Mauritz, David Olefeldt, Susan Natali, Heidi Rodenhizer, Verity Salmon, Christina Schadel, Jens Strauss, Claire C. Treat, Merritt Turetsky Oct 2022

Permafrost And Climate Change: Carbon Cycle Feedbacks From The Warming Arctic, Edward A. G. Schuur, Benjamin W. Abbott, Roisin Commane, Jessica G. Ernakovich, Eugenie Euskirchen, Gustaf Hugelius, Guido Grosse, Miriam Jones, Charlie Koven, Victor Leshyk, David Lawrence, Michael M. Loranty, Marguerite Mauritz, David Olefeldt, Susan Natali, Heidi Rodenhizer, Verity Salmon, Christina Schadel, Jens Strauss, Claire C. Treat, Merritt Turetsky

Faculty Publications

Rapid Arctic environmental change affects the entire Earth system as thawing permafrost ecosystems release greenhouse gases to the atmosphere. Understanding how much permafrost carbon will be released, over what time frame, and what the relative emissions of carbon dioxide and methane will be is key for understanding the impact on global climate. In addition, the response of vegetation in a warming climate has the potential to offset at least some of the accelerating feedback to the climate from permafrost carbon. Temperature, organic carbon, and ground ice are key regulators for determining the impact of permafrost ecosystems on the global carbon …


“Nothing To Do But Be Borne And Steered”: Unpacking Feminist Scripts In Elana Arnold’S Damsel, Jenna Spiering, Nicole Ann Amato Oct 2022

“Nothing To Do But Be Borne And Steered”: Unpacking Feminist Scripts In Elana Arnold’S Damsel, Jenna Spiering, Nicole Ann Amato

Faculty Publications

Feminism in novels marketed for young adults often reflects the values of a popular feminism that relies on individual and personal means of empowerment, rather than critiquing or seeking to dismantle systems of domination. In this paper, we illumminate frameworks and methods for engaging students in careful readings and evaluations of texts marketed as feminist, through an analysis of Elana Arnold’s feminist fairy tale, Damsel (2018). Drawing on theoretical frameworks of popular feminism, feral feminism, and theories of becoming, the authors use Critical Content Anlaysis to explore several tenets in contemporary feminist thought in order to analyze Arnold’s text and …


Innovation Transition Success: Practice Doesn't Make Perfect, Kaitlyn Ryan, Amy M. Cox, Ethan Blake, Clay Koschnick, Alfred E. Thal Jr. Oct 2022

Innovation Transition Success: Practice Doesn't Make Perfect, Kaitlyn Ryan, Amy M. Cox, Ethan Blake, Clay Koschnick, Alfred E. Thal Jr.

Faculty Publications

The authors of this research examine and evaluate organizational factors associated with commercialization under the Air Force Small Business Innovation Research (SBIR) program. Their objective is to improve return on investment. The data set used was the SBIR Phase II program data set, which contains information on 433 SBIR topics with closed contracts reported during Department of Defense (DoD) fiscal years (FYs) 2015 to 2018. Each data point contained characteristics of the topic, including commercialization. Military capability or topic areas were hypothesized to have varying commercialization rates. Incumbency was theorized to be a characteristic of successful programs, while increased company …


Incentivizing Innovation: Promoting Technical Competency To Win Future Wars., James E. Bevins Oct 2022

Incentivizing Innovation: Promoting Technical Competency To Win Future Wars., James E. Bevins

Faculty Publications

Despite numerous studies and initiatives, most current Air Force efforts to add science and technology talent have been insufficient. This begs the question: How does the Air Force incentivize and promote the necessary technical competence required to win future competition, conflicts, and wars? Several key initiatives, grounded in behavioral economics, can incentivize innovation and pursue science and technology expertise. Developed in the context of peer adversaries’ actions; global trends in technology, competition, and conflict; and the global competition for science and technology talent, these recommendations have the potential to reform institutional culture and unleash the creativity and talent of the …


Oxygen Vacancies In Lib3O5 Crystals And Their Role In Nonlinear Absorption, Brian C. Holloway, Christopher A. Lenyk, Timothy D. Gustafson, Nancy C. Giles Oct 2022

Oxygen Vacancies In Lib3O5 Crystals And Their Role In Nonlinear Absorption, Brian C. Holloway, Christopher A. Lenyk, Timothy D. Gustafson, Nancy C. Giles

Faculty Publications

LiB3O5 (LBO) crystals are used to generate the second, third, and fourth harmonics of near-infrared solid-state lasers. At high power levels, the material’s performance is adversely affected by nonlinear absorption. We show that as-grown crystals contain oxygen and lithium vacancies. Transient absorption bands are formed when these intrinsic defects serve as traps for “free” electrons and holes created by x rays or by three- and four-photon absorption processes. Trapped electrons introduce a band near 300 nm and trapped holes produce bands in the 500-600 nm region. Electron paramagnetic resonance (EPR) is used to identify and characterize the …


Transmission Roles Of Symptomatic And Asymptomatic Covid-19 Cases: A Modelling Study, Jianbin Tan, Yang Ge, Leonardo Martinez, Jimin Sun, Changwei Li, Adrianna Westbrook, Enfu Chen, Jinren Pan, Yang Li, Wei Cheng, Feng Ling, Zhinping Chen, Ye Shen, Hui Huang Sep 2022

Transmission Roles Of Symptomatic And Asymptomatic Covid-19 Cases: A Modelling Study, Jianbin Tan, Yang Ge, Leonardo Martinez, Jimin Sun, Changwei Li, Adrianna Westbrook, Enfu Chen, Jinren Pan, Yang Li, Wei Cheng, Feng Ling, Zhinping Chen, Ye Shen, Hui Huang

Faculty Publications

Coronavirus disease 2019 (COVID-19) asymptomatic cases are hard to identify, impeding transmissibility estimation. The value of COVID-19 transmissibility is worth further elucidation for key assumptions in further modelling studies. Through a population-based surveillance network, we collected data on 1342 confirmed cases with a 90-days follow-up for all asymptomatic cases. An age-stratified compartmental model containing contact information was built to estimate the transmissibility of symptomatic and asymptomatic COVID-19 cases. The difference in transmissibility of a symptomatic and asymptomatic case depended on age and was most distinct for the middle-age groups. The asymptomatic cases had a 66.7% lower transmissibility rate than symptomatic …


Using Whole-Brain Diffusion Tensor Analysis To Evaluate White Matter Structural Correlates Of Delayed Visuospatial Memory And One-Week Motor Skill Retention In Nondemented Older Adults: A Preliminary Study, Jennapher Lingo Vangilder, Maurizio Bergamino, Andrew Hooyman, Megan C. Fitzhugh, Corianne Rogalsky, Jill C. Stewart, Scott C. Beeman, Sydney Y. Schaefer Sep 2022

Using Whole-Brain Diffusion Tensor Analysis To Evaluate White Matter Structural Correlates Of Delayed Visuospatial Memory And One-Week Motor Skill Retention In Nondemented Older Adults: A Preliminary Study, Jennapher Lingo Vangilder, Maurizio Bergamino, Andrew Hooyman, Megan C. Fitzhugh, Corianne Rogalsky, Jill C. Stewart, Scott C. Beeman, Sydney Y. Schaefer

Faculty Publications

Skill retention is important for motor rehabilitation outcomes. Recent work has demonstrated that delayed visuospatial memory performance may predict motor skill retention in older and neuropathological populations. White matter integrity between parietal and frontal cortices may explain variance in upper-extremity motor learning tasks and visuospatial processes. We performed a whole-brain analysis to determine the white matter correlates of delayed visuospatial memory and one-week motor skill retention in nondemented older adults. We hypothesized that better frontoparietal tract integrity would be positively related to better behavioral performance. Nineteen participants (age>58) completed diffusion-weighted imaging, then a clinical test of delayed visuospatial memory …


Dietary Inflammatory Index And Mortality From All Causes, Cardiovascular Disease, And Cancer: A Prospective Study, Zhen Lin, Yanfei Feng, Nitin Shivappa Mbbs, Mph, Ph.D., James R. Hébert Scd, Xin Xu Sep 2022

Dietary Inflammatory Index And Mortality From All Causes, Cardiovascular Disease, And Cancer: A Prospective Study, Zhen Lin, Yanfei Feng, Nitin Shivappa Mbbs, Mph, Ph.D., James R. Hébert Scd, Xin Xu

Faculty Publications

The Energy-adjusted Dietary Inflammatory Index (E-DIITM) is a comprehensive, literature-derived index for assessing the effect of dietary constituents on inflammatory biomarkers and inflammation-related chronic diseases. Several studies have examined the association between E-DII scores and mortality, with results that vary across populations. Therefore, in the present study, we aimed to investigate the potential association between E-DII scores and all-cause, cardiovascular disease (CVD), and cancer mortality using data from the Prostate, Lung, Colorectal and Ovarian (PLCO) Screening Trial. E-DII scores, calculated based on a food-frequency questionnaire, were analyzed both as a continuous variable and after categorization into quintiles. A multivariate Cox …


Availability Of Hospital-Based Cancer Services Before And After Rural Hospital Closure, 2008-2017, Whitney Zahnd Ph.D., Peiyin Hung Ph.D., Sylvia Kewei Shi, Anja Zgodic, Melinda A. Merrell Ph.D., Elizabeth L. Crouch, Janice C. Probst, Jan Eberth Ph.D. Sep 2022

Availability Of Hospital-Based Cancer Services Before And After Rural Hospital Closure, 2008-2017, Whitney Zahnd Ph.D., Peiyin Hung Ph.D., Sylvia Kewei Shi, Anja Zgodic, Melinda A. Merrell Ph.D., Elizabeth L. Crouch, Janice C. Probst, Jan Eberth Ph.D.

Faculty Publications

Introduction

Rural populations have less access to cancer care services and experience higher cancer mortality rates than their urban counterparts, which may be exacerbated by hospital closures. Our objective was to examine the impact of hospital closures on access to cancer-relevant hospital services across hospital service areas (HSAs).

Methods

We used American Hospital Association survey data from 2008 to 2017 to examine the change in access to cancer-related screening and treatment services across rural HSAs that sustained hospitals over time, experienced any closures, or had all hospitals close. We performed a longitudinal analysis to assess the association between hospital closure …


Neighborhood Characteristics And Dementia Symptomology Among Community-Dwelling Older Adults With Alzheimer’S Disease, Dana M. Alhasan, Matthew C. Lohman Ph.D., Jana A. Hirsch, Margaret Chandlee Miller Ms, Ph.D., Bo Cai Ph.D., Chandra L. Jackson Sep 2022

Neighborhood Characteristics And Dementia Symptomology Among Community-Dwelling Older Adults With Alzheimer’S Disease, Dana M. Alhasan, Matthew C. Lohman Ph.D., Jana A. Hirsch, Margaret Chandlee Miller Ms, Ph.D., Bo Cai Ph.D., Chandra L. Jackson

Faculty Publications

Background: Neuropsychiatric symptoms (NPSs) lead to myriad poor health outcomes among individuals with Alzheimer’s disease (AD). Prior studies have observed associations between the various aspects of the home environment and NPSs, but macro-level environmental stressors (e.g., neighborhood income) may also disrupt the neuronal microenvironment and exacerbate NPSs. Yet, to our knowledge, no studies have investigated the relationship between the neighborhood environment and NPSs.

Methods: Using 2010 data among older adults with AD collected from a sample of the South Carolina Alzheimer’s Disease Registry, we estimated cross-sectional associations between neighborhood characteristics and NPSs in the overall population and by race/ethnicity. Neighborhood …


The Roles Of Flux Tube Entropy And Effective Gravity In The Inward Plasma Transport At Saturn, S. Wing, M. F. Thomsen, J. R. Johnson, D. G. Mitchell, R. C. Allen, X. Ma, P. A. Delamere Sep 2022

The Roles Of Flux Tube Entropy And Effective Gravity In The Inward Plasma Transport At Saturn, S. Wing, M. F. Thomsen, J. R. Johnson, D. G. Mitchell, R. C. Allen, X. Ma, P. A. Delamere

Faculty Publications

The inward plasma transport at the Saturnian magnetosphere is examined using the flux tube interchange stability formalism developed by Southwood & Kivelson. Seven events are selected. Three cases are considered: (1) the injected flux tube and ambient plasmas are nonisotropic, (2) the injected flux tube and ambient plasmas are isotropic, and (3) the injected flux tube plasma is isotropic, but the ambient plasma is nonisotropic. Case 1 may be relevant for fresh injections, while case 3 may be relevant for old injections. For cases 1 and 2, all but one event have negative stability conditions, suggesting that the flux tube …


Clustering Behavior In Solar Flare Dynamics, Elmer C. Rivera, Jay R. Johnson, Jonathan Homan, Simon Wing Sep 2022

Clustering Behavior In Solar Flare Dynamics, Elmer C. Rivera, Jay R. Johnson, Jonathan Homan, Simon Wing

Faculty Publications

The solar magnetic activity cycle provides energy input that is released in intense bursts of radiation known as solar flares. As such, the dynamics of the activity cycle is embedded in the sequence of times between the flare events. Recent analysis shows that solar flares exhibit memory on different timescales. These previous studies showed that the time ordering of flare events is not random, but rather there is dependence between successive flares. In the present work, the clustering of flares is demonstrated through a straightforward nonparametric method where the cumulative distribution function of successive flares is compared with the cumulative …


Wildfire Aerosol Deposition Likely Amplified A Summertime Arctic Phytoplankton Bloom, Mathieu Ardyna, Douglas S. Hamilton, Tristan Harmel, Léo Lacour, Diana N. Bernstein, Julien Laliberté, Christopher Horvat, Rémi Laxenaire, Matthew M. Mills, Gert Van Dijken, Igor Polyakov, Hervé Claustre, Natalie Mahowald, Kevin Robert Arrigo Sep 2022

Wildfire Aerosol Deposition Likely Amplified A Summertime Arctic Phytoplankton Bloom, Mathieu Ardyna, Douglas S. Hamilton, Tristan Harmel, Léo Lacour, Diana N. Bernstein, Julien Laliberté, Christopher Horvat, Rémi Laxenaire, Matthew M. Mills, Gert Van Dijken, Igor Polyakov, Hervé Claustre, Natalie Mahowald, Kevin Robert Arrigo

Faculty Publications

Summertime wildfire activity is increasing in boreal forest and tundra ecosystems in the Northern Hemisphere. However, the impact of long range transport and deposition of wildfire aerosols on biogeochemical cycles in the Arctic Ocean is unknown. Here, we use satellite-based ocean color data, atmospheric modeling and back trajectory analysis to investigate the transport and fate of aerosols emitted from Siberian wildfires in summer 2014 and their potential impact on phytoplankton dynamics in the Arctic Ocean. We detect large phytoplankton blooms near the North Pole (up to 82°N in the eastern Eurasian Basin). Our analysis indicates that these blooms were induced …


Yin And Yang Of Cannabinoid Cb1 Receptor: Cb1 Deletion In Immune Cells Causes Exacerbation While Deletion In Non-Immune Cells Attenuates Obesity, Kathryn Miranda, William Becker, Philip B. Busbee, Nicholas Dopkins, Osama A. Abdulla, Yin Zhong, Jiajia Zhang Ph.D., Mitzi Nagarkatti, Prakash S. Nagarkatti Sep 2022

Yin And Yang Of Cannabinoid Cb1 Receptor: Cb1 Deletion In Immune Cells Causes Exacerbation While Deletion In Non-Immune Cells Attenuates Obesity, Kathryn Miranda, William Becker, Philip B. Busbee, Nicholas Dopkins, Osama A. Abdulla, Yin Zhong, Jiajia Zhang Ph.D., Mitzi Nagarkatti, Prakash S. Nagarkatti

Faculty Publications

While blockade of cannabinoid receptor 1 (CB1) has been shown to attenuate diet-induced obesity (DIO), its relative role in different cell types has not been tested. The current study investigated the role of CB1 in immune vs non-immune cells during DIO by generating radiation-induced bone marrow chimeric mice that expressed functional CB1 in all cells except the immune cells or expressed CB1 only in immune cells. CB1-/- recipient hosts were resistant to DIO, indicating that CB1 in non-immune cells is necessary for induction of DIO. Interestingly, chimeras with CB1-/- in immune cells showed exacerbation in DIO combined with …


Applications Of The Harary-Sachs Theorem For Hypergraphs, Gregory J. Clark, Joshua N. Cooper Sep 2022

Applications Of The Harary-Sachs Theorem For Hypergraphs, Gregory J. Clark, Joshua N. Cooper

Faculty Publications

The Harary-Sachs theorem for k-uniform hypergraphs equates the codegree-d coefficient of the adjacency characteristic polynomial of a uniform hypergraph with a weighted sum of subgraph counts over certain multi-hypergraphs with d edges. We begin by showing that the classical Harary-Sachs theorem for graphs is indeed a special case of this general theorem. To this end we apply the generalized Harary-Sachs theorem to the leading coefficients of the characteristic polynomial of various hypergraphs. In particular, we provide explicit and asymptotic formulas for the contribution of the k-uniform simplex to the codegree-d coefficient. Moreover, we provide an explicit formula for the leading …


Pest Population Dynamics Are Related To A Continental Overwintering Gradient, Douglas Lawton, Anders S. Huseth, George G. Kennedy, Amy C. Morey, William D. Hutchison, Dominic D. Reisig, Seth J. Dorman, De Shae Dillard, Robert C. Venette, Russell L. Groves, John J. Adamczyk, Izailda Barbosa Dos Santos, Tracey Baute, Sebe Brown, Eric Burkness, Ashley Dean, Galen P. Dively, Hélène B. Doughty, Shelby J. Fleischer, Jessica Green, Jeremy K. Greene, Krista Hamilton, Erin Hodgson, Thomas Hunt, David Kerns, Billy Rogers Leonard, Sean Malone, Fred Musser, David Owens, John C. Palumbo, Silvana Paula-Moraes, Julie A. Peterson, Ricardo Ramirez Sep 2022

Pest Population Dynamics Are Related To A Continental Overwintering Gradient, Douglas Lawton, Anders S. Huseth, George G. Kennedy, Amy C. Morey, William D. Hutchison, Dominic D. Reisig, Seth J. Dorman, De Shae Dillard, Robert C. Venette, Russell L. Groves, John J. Adamczyk, Izailda Barbosa Dos Santos, Tracey Baute, Sebe Brown, Eric Burkness, Ashley Dean, Galen P. Dively, Hélène B. Doughty, Shelby J. Fleischer, Jessica Green, Jeremy K. Greene, Krista Hamilton, Erin Hodgson, Thomas Hunt, David Kerns, Billy Rogers Leonard, Sean Malone, Fred Musser, David Owens, John C. Palumbo, Silvana Paula-Moraes, Julie A. Peterson, Ricardo Ramirez

Faculty Publications

Overwintering success is an important determinant of arthropod populations that must be considered as climate change continues to influence the spatiotemporal population dynamics of agricultural pests. Using a long-term monitoring database and biologically relevant overwintering zones, we modeled the annual and seasonal population dynamics of a common pest, Helicoverpa zea (Boddie), based on three overwintering suitability zones throughout North America using four decades of soil temperatures: the southern range (able to persist through winter), transitional zone (uncertain overwintering survivorship), and northern limits (unable to survive winter). Our model indicates H. zea population dynamics are hierarchically structured with continental-level effects that …


Deep-Turbulence Phase Compensation Using Tiled Arrays, Mark F. Spencer, Terry J. Brennan Sep 2022

Deep-Turbulence Phase Compensation Using Tiled Arrays, Mark F. Spencer, Terry J. Brennan

Faculty Publications

Tiled arrays use modulo-2π phase compensation and coherent beam combination to correct for the effects of deep turbulence. As such, this paper uses wave-optics simulations to compare the closed-loop performance of tiled arrays to a branch-point-tolerant phase reconstructor known as LSPV+7 [Appl. Opt. 53, 3821 (2014) [CrossRef] ]. The wave-optics simulations make use of a point-source beacon and are setup with weak-to-strong scintillation conditions. This setup enables a trade-space exploration in support of a power-in-the-bucket comparison with LSPV+7. In turn, the results show that tiled arrays outperform LSPV+7 when transitioning from weak-to-strong scintillation conditions. These results are both …


Pulse-Quality Metric For Nonstationary Partially Coherent Fields, Milo W. Hyde Iv, Olga Korotkova, Mark F. Spencer Sep 2022

Pulse-Quality Metric For Nonstationary Partially Coherent Fields, Milo W. Hyde Iv, Olga Korotkova, Mark F. Spencer

Faculty Publications

This paper generalizes a pulse-quality metric referred to as P2, i.e., the time analogue of Siegman’s beam quality factor M2, to include pulsed (nonstationary) random fields of any state of coherence. The analysis begins with the derivation of a general P2 relation, which we then specialize to the important cases of coherent and Schell-model pulsed beams. As examples, we derive the P2 for two stochastic sources: (1) a cosine Gaussian-correlated Schell-model pulsed beam and (2) a nonuniformly correlated pulsed beam. For both of these sources, we generate (in simulation) random instances of each and …


Resonant Plasmonic–Biomolecular Chiral Interactions In The Far-Ultraviolet: Enantiomeric Discrimination Of Sub-10 Nm Amino Acid Films, Tiago Ramos Leite, Lin Zschiedrich, Orhan Kizilkaya, Kevin M. Mcpeak Sep 2022

Resonant Plasmonic–Biomolecular Chiral Interactions In The Far-Ultraviolet: Enantiomeric Discrimination Of Sub-10 Nm Amino Acid Films, Tiago Ramos Leite, Lin Zschiedrich, Orhan Kizilkaya, Kevin M. Mcpeak

Faculty Publications

Resonant plasmonic–molecular chiral interactions are a promising route to enhanced biosensing. However, biomolecular optical activity primarily exists in the far-ultraviolet regime, posing significant challenges for spectral overlap with current nano-optical platforms. We demonstrate experimentally and computationally the enhanced chiral sensing of a resonant plasmonic–biomolecular system operating in the far-UV. We develop a full-wave model of biomolecular films on Al gammadion arrays using experimentally derived chirality parameters. Our calculations show that detectable enhancements in the chiroptical signals from small amounts of biomolecules are possible only when tight spectral overlap exists between the plasmonic and biomolecular chiral responses. We support this conclusion …