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Immune Genotypes, Immune Responses, And Survival In A Wild Bird Population, Martha J. Nelson-Flower, Leanne A. Grieves, Jane M. Reid, Ryan R. Germain, Savo Lazic, Sabrina S. Taylor, Elizabeth A. Macdougall-Shackleton, Peter Arcese Jun 2023

Immune Genotypes, Immune Responses, And Survival In A Wild Bird Population, Martha J. Nelson-Flower, Leanne A. Grieves, Jane M. Reid, Ryan R. Germain, Savo Lazic, Sabrina S. Taylor, Elizabeth A. Macdougall-Shackleton, Peter Arcese

Faculty Publications

Individuals vary in their immune genotype, inbreeding coefficient f, immune responses, survival to adulthood, and adult longevity. However, whether immune genes predict survival or longevity, whether such relationships are mediated through immune responses, and how f affects immune genotype remain unclear. We use a wild song sparrow (Melospiza melodia) population in which survival to adulthood, adult longevity, and f were measured precisely, and in which immune responses have previously been assessed. We investigate four toll-like receptor (TLR) and the major histocompatibility complex (MHC) class IIB exon 2 genes. We test whether immune genes predict fitness (survival to adulthood or adult …


Students' Consumption Of High And Low Nutrition Foods And Reduced Plate Waste By Schools' Wellness-Related Policies And Garden Program Participation, Andrea S. Richardson, Alvin Nugroho, Tamara Dubowitz, Dana Schultz, Corby K. Martin Jun 2023

Students' Consumption Of High And Low Nutrition Foods And Reduced Plate Waste By Schools' Wellness-Related Policies And Garden Program Participation, Andrea S. Richardson, Alvin Nugroho, Tamara Dubowitz, Dana Schultz, Corby K. Martin

Clinical Research Faculty Publications

Background: Participation in school-based programs that may support children's nutritious dietary behaviours varies across schools. We examined school participation in wellness-related policies, school-based garden programs and students' dietary behaviours. Methods: Among matching schools who did and did not participate in school-based garden programs, we analysed the lunches of 80 Pittsburgh Public Schools (PPS) students in 1st, 2nd, 6th and 7th grades during Autumn 2019 using digital food photography. We also acquired school wellness policy data. Using cross-sectional linear regression, we estimated the association between school-based garden programming, wellness-related policies and dietary outcomes, adjusting for grade. Results: School's implementation of nutrition …


Molecular Research In Rice, Prasanta K. Subudhi Jun 2023

Molecular Research In Rice, Prasanta K. Subudhi

Faculty Publications

No abstract provided.


Genome-Wide Association Study Identified Candidate Genes For Alkalinity Tolerance In Rice, Lovepreet Singh, Rajat Pruthi, Sandeep Chapagain, Prasanta K. Subudhi Jun 2023

Genome-Wide Association Study Identified Candidate Genes For Alkalinity Tolerance In Rice, Lovepreet Singh, Rajat Pruthi, Sandeep Chapagain, Prasanta K. Subudhi

Faculty Publications

Alkalinity stress is a major hindrance to enhancing rice production globally due to its damaging effect on plants’ growth and development compared with salinity stress. However, understanding of the physiological and molecular mechanisms of alkalinity tolerance is limited. Therefore, a panel of indica and japonica rice genotypes was evaluated for alkalinity tolerance at the seedling stage in a genome-wide association study to identify tolerant genotypes and candidate genes. Principal component analysis revealed that traits such as alkalinity tolerance score, shoot dry weight, and shoot fresh weight had the highest contribution to variations in tolerance, while shoot Na+ concentration, shoot Na+:K+ …


A Comparison Of Bat Calls Recorded By Two Acoustic Monitors, Jane M. Kunberger, Ashley M. Long Jun 2023

A Comparison Of Bat Calls Recorded By Two Acoustic Monitors, Jane M. Kunberger, Ashley M. Long

Faculty Publications

Recent advances in low-cost autonomous recording unit (ARU) technology have made large-scale bat monitoring projects more practical, but several key features of ARUs (e.g., microphone quality and triggering thresholds) can influence their ability to detect and record bats. As such, it is important to quantify and report variation in ARU performance as new recording systems become available. We used the automated classification software SonoBat to compare the numbers of call files, echolocation pulses, and species recorded by a commonly used, full-spectrum bat detector-the Song Meter SM4BAT-FS-and a less expensive, open-source ARU that can detect ultrasound-the AudioMoth. We deployed paired ARUs …


Equity And Behavioral Digital Health Interventions: Strategies To Improve Benefit And Reach, Sarah J. Miller, Jamilia R. Sly, Kassandra I. Alcaraz, Kimlin Ashing, Shannon M. Christy, Brian Gonzalez, Qian Lu, Robert L. Newton, Michelle Redmond, Megan Shen, Kamilah Thomas-Purcell, Jean Yi, Tiffany Veinot, Cathy D. Meade Jun 2023

Equity And Behavioral Digital Health Interventions: Strategies To Improve Benefit And Reach, Sarah J. Miller, Jamilia R. Sly, Kassandra I. Alcaraz, Kimlin Ashing, Shannon M. Christy, Brian Gonzalez, Qian Lu, Robert L. Newton, Michelle Redmond, Megan Shen, Kamilah Thomas-Purcell, Jean Yi, Tiffany Veinot, Cathy D. Meade

Population and Public Health Science Faculty Publications

Background: Behavioral digital health interventions (e.g., mobile apps, websites, wearables) have been applied widely to improve health outcomes. However, many groups (e.g., people with low income levels, people who are geographically isolated, older adults) may face obstacles to technology access and use. In addition, research has found that biases and stereotypes can be embedded within digital health interventions. As such, behavioral digital health interventions that intend to improve overall population health may unintentionally widen health-related inequities. Purpose: This commentary offers guidance and strategies to mitigate these risks when using technology as a means for delivering a behavioral health intervention. Methods: …


Demystifying Longitudinal Data Analyses Using Structural Equation Models In School Psychology, Garret J. Hall, Kelly N. Clark Jun 2023

Demystifying Longitudinal Data Analyses Using Structural Equation Models In School Psychology, Garret J. Hall, Kelly N. Clark

Faculty Publications

Structural equation models (SEM) are a method of latent variable analysis that offer a high degree of flexibility in terms of modeling methods for applied research questions. Recent advancements associated with longitudinal SEM have unlocked innovative ways to decompose variance and to estimate mean trends over time (e.g., Allison et al., 2017; Berry & Willoughby, 2017; Hamaker et al., 2015; McArdle & Nesselroade, 2014). However, these longitudinal methods are not necessarily readily accessible to scholars seeking to advance theory and practice in school psychology. Importantly, not all longitudinal data are the same and not all longitudinal SEMs are the same; …


Associations Between Neuropsychiatric Symptoms Of Affective And Vegetative Domains And Brain Morphology In Aging People With Mild Cognitive Impairment And Alzheimer's Disease, Adriana Cannizzaro, Lucas Ronat, Lyna Mariam El Haffaf, Alexandru Hanganu, Michael Weiner, Paul Aisen, Paul Aisen, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, William Jagust, John Q. Trojanowki, John Q. Trojanowki, Arthur W. Toga, Arthur W. Toga, Laurel Beckett, Laurel Beckett, Robert C. Green, Robert C. Green, Andrew J. Saykin, Andrew J. Saykin, John Morris, Enchi Liu, Tom Montine, Ronald Petersen, Ronald Petersen, Anthony Gamst, Anthony Gamst, Ronald G. Thomas, Michael Donohue, Michael Donohue, Sarah Walter, Devon Gessert Jun 2023

Associations Between Neuropsychiatric Symptoms Of Affective And Vegetative Domains And Brain Morphology In Aging People With Mild Cognitive Impairment And Alzheimer's Disease, Adriana Cannizzaro, Lucas Ronat, Lyna Mariam El Haffaf, Alexandru Hanganu, Michael Weiner, Paul Aisen, Paul Aisen, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, William Jagust, John Q. Trojanowki, John Q. Trojanowki, Arthur W. Toga, Arthur W. Toga, Laurel Beckett, Laurel Beckett, Robert C. Green, Robert C. Green, Andrew J. Saykin, Andrew J. Saykin, John Morris, Enchi Liu, Tom Montine, Ronald Petersen, Ronald Petersen, Anthony Gamst, Anthony Gamst, Ronald G. Thomas, Michael Donohue, Michael Donohue, Sarah Walter, Devon Gessert

Clinical Research Faculty Publications

Objective: Neuropsychiatric symptoms (NPS) are common in mild cognitive impairment (MCI) and even more in Alzheimer's disease (AD). The symptom-based cluster including nighttime disturbances, depression, appetite changes, anxiety, and apathy (affective and vegetative symptoms) was associated with an increased risk of dementia in MCI and has common neuroanatomical associations. Our objective was to investigate the differences in brain morphology associations with affective and vegetative symptoms between three groups: cognitively normal older adults (CN), MCI and AD. Material and Methods: Alzheimer's Disease Neuroimaging Initiative data of 223 CN, 367 MCI and 175 AD, including cortical volumes, surface areas and thicknesses and …


Regional Neuroanatomic Effects On Brain Age Inferred Using Magnetic Resonance Imaging And Ridge Regression, Roy J. Massett, Alexander S. Maher, Phoebe E. Imms, Anar Amgalan, Nikhil N. Chaudhari, Nahian F. Chowdhury, Andrei Irimia, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John C. Morris, Richard J. Perrin, Leslie M. Shaw, Zaven Khachaturian, Maria Carrillo, William Potter, Lisa Barnes, Marie Bernard, Hector González, Carole Ho, John K. Hsiao, Jonathan Jackson, Eliezer Masliah, Donna Masterman, Ozioma Okonkwo, Laurie Ryan, Nina Silverberg Jun 2023

Regional Neuroanatomic Effects On Brain Age Inferred Using Magnetic Resonance Imaging And Ridge Regression, Roy J. Massett, Alexander S. Maher, Phoebe E. Imms, Anar Amgalan, Nikhil N. Chaudhari, Nahian F. Chowdhury, Andrei Irimia, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John C. Morris, Richard J. Perrin, Leslie M. Shaw, Zaven Khachaturian, Maria Carrillo, William Potter, Lisa Barnes, Marie Bernard, Hector González, Carole Ho, John K. Hsiao, Jonathan Jackson, Eliezer Masliah, Donna Masterman, Ozioma Okonkwo, Laurie Ryan, Nina Silverberg

Clinical Research Faculty Publications

The biological age of the brain differs from its chronological age (CA) and can be used as biomarker of neural/cognitive disease processes and as predictor of mortality. Brain age (BA) is often estimated from magnetic resonance images (MRIs) using machine learning (ML) that rarely indicates how regional brain features contribute to BA. Leveraging an aggregate training sample of 3 418 healthy controls (HCs), we describe a ridge regression model that quantifies each region’s contribution to BA. After model testing on an independent sample of 651 HCs, we compute the coefficient of partial determination R̄2p for each regional brain volume to …


Exploring The Experiences Of Pregnant Women In The U.S. During The First Year Of The Covid-19 Pandemic, Courtney E. Williams, Dana Berkowitz, Heather M. Rackin Jun 2023

Exploring The Experiences Of Pregnant Women In The U.S. During The First Year Of The Covid-19 Pandemic, Courtney E. Williams, Dana Berkowitz, Heather M. Rackin

Faculty Publications

In this paper, we integrate the stress process model with symbolic interactionism to frame our analysis of interviews with 35 women who were pregnant and/or gave birth during the first year of the Covid-19 pandemic. We detail three stressors, highlight their variation, and discuss how they coped with these stressors. Women reported having to navigate contradictory information about the public health crisis, but Black participants simultaneously endured added strain from a heightened awareness of racialized violence. To cope with an overabundance of precarious and contradictory messages, some women sought out information (i.e., information gatherers), others eschewed information (i.e., information avoiders), …


Food-Evoked Emotion, Product Acceptance, Food Preference, Food Choice And Consumption: Some New Perspectives, Witoon Prinyawiwatkul Jun 2023

Food-Evoked Emotion, Product Acceptance, Food Preference, Food Choice And Consumption: Some New Perspectives, Witoon Prinyawiwatkul

Faculty Publications

No abstract provided.


Systematic Kmtnet Planetary Anomaly Search. Viii. Complete Sample Of 2019 Subprime Field Planets, Youn Kil Jung, Weicheng Zang, Hanyue Wang, Cheongho Han, Andrew Gould, Andrzej Udalski, Wei Zhu, Michael D. Albrow, Sun Ju Chung, Kyu Ha Hwang, Yoon Hyun Ryu, In Gu Shin, Yossi Shvartzvald, Hongjing Yang, Jennifer C. Yee, Sang Mok Cha, Dong Jin Kim, Seung Lee Kim, Chung Uk Lee, Dong Joo Lee, Yongseok Lee, Byeong Gon Park, Richard W. Pogge, Dan Maoz, Michał K. Szymański, Jan Skowron, Radek Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek Jun 2023

Systematic Kmtnet Planetary Anomaly Search. Viii. Complete Sample Of 2019 Subprime Field Planets, Youn Kil Jung, Weicheng Zang, Hanyue Wang, Cheongho Han, Andrew Gould, Andrzej Udalski, Wei Zhu, Michael D. Albrow, Sun Ju Chung, Kyu Ha Hwang, Yoon Hyun Ryu, In Gu Shin, Yossi Shvartzvald, Hongjing Yang, Jennifer C. Yee, Sang Mok Cha, Dong Jin Kim, Seung Lee Kim, Chung Uk Lee, Dong Joo Lee, Yongseok Lee, Byeong Gon Park, Richard W. Pogge, Dan Maoz, Michał K. Szymański, Jan Skowron, Radek Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek

Faculty Publications

We complete the publication of all microlensing planets (and “possible planets”) identified by the uniform approach of the KMT AnomalyFinder system in the 21 KMT subprime fields during the 2019 observing season, namely, KMT-2019-BLG-0298, KMT-2019-BLG-1216, KMT-2019-BLG-2783, OGLE-2019-BLG-0249, and OGLE-2019-BLG-0679 (planets), as well as OGLE-2019-BLG-0344 and KMT-2019-BLG-0304 (possible planets). The five planets have mean log mass ratio measurements of (−2.6, −3.6, −2.5, −2.2, −2.3), median mass estimates of (1.81, 0.094, 1.16, 7.12, 3.34) M Jup, and median distance estimates of (6.7, 2.7, 5.9, 6.4, 5.6) kpc, respectively. The main scientific interest of these planets is that they complete the AnomalyFinder sample …


Physico-Chemical, Microbiological, And Sensory Characteristics Of Yogurt As Affected By Various Ingredients, Ricardo S. Aleman, Roberto Cedillos, Ryan Page, Douglas Olson, Kayanush Aryana Jun 2023

Physico-Chemical, Microbiological, And Sensory Characteristics Of Yogurt As Affected By Various Ingredients, Ricardo S. Aleman, Roberto Cedillos, Ryan Page, Douglas Olson, Kayanush Aryana

Faculty Publications

L-Glutamine, quercetin, slippery elm bark, marshmallow root, N-acetyl-D-glucosamine, licorice root, maitake mushrooms, and zinc orotate have been reported to help treat leaky gut. The purpose of this research was to explore the impact of these functional ingredients on the physico-chemical, microbiological, and sensory properties of yogurt. The milk from same source was equally divided into 9 pails and the 8 ingredients were randomly assigned to the 8 pails. The control had no ingredient. Milk was fermented to yogurt. The pH, titratable acidity, syneresis, viscosity, color (L*, a*, b*, C*, and h*), Streptococcus thermophilus counts, and Lactobacillus delbrueckii spp. bulgaricus counts …


Effects Of Yogurt With Carao (Cassia Grandis) On Intestinal Barrier Dysfunction, Α-Glycosidase Activity, Lipase Activity, Hypoglycemic Effect, And Antioxidant Activity, Ricardo S. Aleman, Jhunior Marcia, Ryan Page, Shirin Kazemzadeh Pournaki, Daniel Martín-Vertedor, Víctor Manrique-Fernández, Ismael Montero-Fernández, Kayanush Aryana Jun 2023

Effects Of Yogurt With Carao (Cassia Grandis) On Intestinal Barrier Dysfunction, Α-Glycosidase Activity, Lipase Activity, Hypoglycemic Effect, And Antioxidant Activity, Ricardo S. Aleman, Jhunior Marcia, Ryan Page, Shirin Kazemzadeh Pournaki, Daniel Martín-Vertedor, Víctor Manrique-Fernández, Ismael Montero-Fernández, Kayanush Aryana

Faculty Publications

Cell inflammation disrupts intestinal barrier functions and may cause disorders related to a leaky gut, possibly leading to diabetes. The objective of this study was to determine if carao (Cassia grandis) incorporated into yogurt enhances in vitro intestinal barrier function. To achieve this goal, Caco-2 cells were used as a model of intestinal barrier permeability. Caco-2 cells were treated with cytokines (interleukin-1β, tumor necrosis factor-α, interferon-γ, and lipopolysaccharide (LPS)) and yogurt with carao yogurt (CY) at different doses (1.3 g/L, 2.65 g/L, and 5.3 g/L). Real-time quantitative polymerase chain and immunofluorescence microscopy were applied to evaluate the expression and localization …


8(Meso)-Pyridyl-Bodipys: Effects Of 2,6-Substitution With Electron-Withdrawing Nitro, Chloro, And Methoxycarbonyl Groups, Caroline Ndung’U, Petia Bobadova-Parvanova, Daniel J. Lamaster, Dylan Goliber, Frank R. Fronczek, Maria Da Graça H. Vicente Jun 2023

8(Meso)-Pyridyl-Bodipys: Effects Of 2,6-Substitution With Electron-Withdrawing Nitro, Chloro, And Methoxycarbonyl Groups, Caroline Ndung’U, Petia Bobadova-Parvanova, Daniel J. Lamaster, Dylan Goliber, Frank R. Fronczek, Maria Da Graça H. Vicente

Faculty Publications

The introduction of electron-withdrawing groups on 8(meso)-pyridyl-BODIPYs tends to increase the fluorescence quantum yields of this type of compound due to the decrease in electronic charge density on the BODIPY core. A new series of 8(meso)-pyridyl-BODIPYs bearing a 2-, 3-, or 4-pyridyl group was synthesized and functionalized with nitro and chlorine groups at the 2,6-positions. The 2,6-methoxycarbonyl-8-pyridyl-BODIPYs analogs were also synthesized by condensation of 2,4-dimethyl-3-methoxycarbonyl-pyrrole with 2-, 3-, or 4-formylpyridine followed by oxidation and boron complexation. The structures and spectroscopic properties of the new series of 8(meso)-pyridyl-BODIPYs were investigated both experimentally and computationally. The BODIPYs bearing 2,6-methoxycarbonyl groups showed enhanced …


Modeling Behavioral Economics Strategies In Social Marketing Messages To Promote Vegetable Consumption To Low-Resource Louisiana Residents: A Conjoint Analysis, Linda Fergus, Andrew R. Long, Denise Holston Jun 2023

Modeling Behavioral Economics Strategies In Social Marketing Messages To Promote Vegetable Consumption To Low-Resource Louisiana Residents: A Conjoint Analysis, Linda Fergus, Andrew R. Long, Denise Holston

Faculty Publications

Background: Behavioral economics strategies implemented within social marketing campaigns improve eating behavior. Objective: To identify which behavioral economics strategies in social marketing messages particularly messengers, norms, and commitments will promote low-income Louisiana residents to add more vegetables to meals. Design: Full profile traditional conjoint analysis survey with single concept ratings. Participants: Purposive sample of low-resource Louisiana residents (N = 213) Setting: Online survey. Intervention: Participants rated randomized concepts that featured a messenger and a message. Main outcome measure: Ratings (one to nine) of likelihood to add vegetables to meals. Statistical analysis: A model of ratings was generated using mixed-effects multiple …


Development Of Gluten-Free Bread Using Teosinte (Dioon Mejiae) Flour In Combination With High-Protein Brown Rice Flour And High-Protein White Rice Flour, Franklin Delarca Ruiz, Ricardo S. Aleman, Shirin Kazemzadeh Pournaki, Mallerly Sarmiento Madrid, Andrea Muela, Yeimi Mendoza, Jhunior Marcia Fuentes, Witoon Prinyawiwatkul, Joan M. King Jun 2023

Development Of Gluten-Free Bread Using Teosinte (Dioon Mejiae) Flour In Combination With High-Protein Brown Rice Flour And High-Protein White Rice Flour, Franklin Delarca Ruiz, Ricardo S. Aleman, Shirin Kazemzadeh Pournaki, Mallerly Sarmiento Madrid, Andrea Muela, Yeimi Mendoza, Jhunior Marcia Fuentes, Witoon Prinyawiwatkul, Joan M. King

Faculty Publications

Gluten-free bread is an important product that is under development using different sources, such as rice and starchy plants. Teosinte seeds are utilized by ethnic groups in Honduras to produce gluten-free flour to prepare traditional baked goods and beverages. The quality of gluten-free products could vary depending on flour properties, such as amylose content, particle size, and water absorption capacity. A good strategy for developing baked goods is to mix different cereal grain sources to optimize their physicochemical properties. As a result, the current study aimed to develop bread from novel flours including teosinte (TF), high-protein brown rice (BRF), and …


An Examination Of Frontline Employee–Customer Incidental Similarities In Service Failure And Recovery Contexts, Kristina K. Lindsey-Hall, Susana Jaramillo, Thomas L. Baker, Daniel G. Bachrach Jun 2023

An Examination Of Frontline Employee–Customer Incidental Similarities In Service Failure And Recovery Contexts, Kristina K. Lindsey-Hall, Susana Jaramillo, Thomas L. Baker, Daniel G. Bachrach

Faculty Publications

Developing rapport during the “moment of truth” when frontline employees (FLEs) interact with customers has long been an important topic for researchers and managers. We suggest incidental similarities—seemingly trivial shared points of comparison between customers and FLEs—can play a vital role during this juncture in service failure and recovery contexts. Across two experimental studies, we investigate several relationships impacted by the presence or absence of an incidental similarity between FLEs and customers for their effect on satisfaction and repatronage intentions. Results suggest incidental similarities can reduce failure attributions toward service providers and improve these important customer-related outcomes (study 1). Results …


Profiling Consumers: Examination Of Chinese Gen Z Consumers’ Sustainable Fashion Consumption, Yanbo Zhang, Chuanlan Liu, Yanru Lyu Jun 2023

Profiling Consumers: Examination Of Chinese Gen Z Consumers’ Sustainable Fashion Consumption, Yanbo Zhang, Chuanlan Liu, Yanru Lyu

Faculty Publications

The textile and apparel industry is widely recognized for its negative impact on the environment and society, and China is one of the largest fashion-consumption markets worldwide. There has been a growing awareness and effort to address these concerns in China, and Chinese Gen-Z consumers are playing a crucial role in shaping sustainable practices. This study aimed to identify and profile Gen-Z consumers with substantial engagement in sustainable fashion consumption in China. Data were collected from 292 Chinese Gen-Z adults from three major cities, Beijing, Shanghai, and Guangzhou, using a convenience sampling strategy and the snowball approach. Cluster analysis was …


The Distribution Of Surface Soil Moisture Over Space And Time In Eastern Taylor Valley, Antarctica, Mark R. Salvatore, John E. Barrett, Laura E. Fackrell, Eric R. Sokol, Joseph S. Levy, Lily C. Kuentz, Michael N. Gooseff, Byron J. Adams, Sarah N. Power, J. Paul Knightly, Haley M. Matul, Brian Szutu, Peter T. Doran Jun 2023

The Distribution Of Surface Soil Moisture Over Space And Time In Eastern Taylor Valley, Antarctica, Mark R. Salvatore, John E. Barrett, Laura E. Fackrell, Eric R. Sokol, Joseph S. Levy, Lily C. Kuentz, Michael N. Gooseff, Byron J. Adams, Sarah N. Power, J. Paul Knightly, Haley M. Matul, Brian Szutu, Peter T. Doran

Faculty Publications

Available soil moisture is thought to be the limiting factor for most ecosystem processes in the cold polar desert of the McMurdo Dry Valleys (MDVs) of Antarctica. Previous studies have shown that microfauna throughout the MDVs are capable of biological activity when sufficient soil moisture is available (~2–10% gravimetric water content), but few studies have attempted to quantify the distribution, abundance, and frequency of soil moisture on scales beyond that of traditional field work or local field investigations. In this study, we present our work to quantify the soil moisture content of soils throughout the Fryxell basin using multispectral satellite …


Testing Tectonostratigraphic Hypotheses Of The Blountian Phase Of The Taconic Orogeny In The Southern Appalachians Through An Integrated Geochronological And Sedimentological Study Of Ordovician K-Bentonites And Quartz Arenites, Achim D. Herrmann, John T. Haynes, Richard Robinet, Peter D. Clift, Keith E. Goggin Jun 2023

Testing Tectonostratigraphic Hypotheses Of The Blountian Phase Of The Taconic Orogeny In The Southern Appalachians Through An Integrated Geochronological And Sedimentological Study Of Ordovician K-Bentonites And Quartz Arenites, Achim D. Herrmann, John T. Haynes, Richard Robinet, Peter D. Clift, Keith E. Goggin

Faculty Publications

The tectonic setting of the southernmost part of the eastern margin of Laurentia during the Blountian tectophase (~472–452 Ma) of the Ordovician Taconic Orogeny remains unresolved. Tephras produced by explosive volcanism during this early phase of the orogeny are now K-bentonites, and in many locations, they are interbedded with mature to supermature quartz arenites. We conducted U-Pb analyses of detrital zircons from the sandstones, and of zoned magmatic zircons from the K-bentonites, to constrain the tectonostratigraphic setting with more precision. We also used geochemical fingerprinting of apatite phenocrysts to correlate the K-bentonites in these sandstones along the tectonic front, and …


Constraints On The Timing Of The India-Asia Collision And Unroofing History Of The Himalayan Orogen Using Detrital Zircon U-Pb-Hf And Whole-Rock Sr-Nd Isotopes In Cretaceous-Miocene Lesser Himalayan Sedimentary Rocks, Wei Feng, Qingquan Meng, Chunhui Song, Xiaomin Fang, Guangsheng Zhuang, Pengju He, Shufen Yang, Jing Zhang, Yongfa Chen, Yihu Zhang Jun 2023

Constraints On The Timing Of The India-Asia Collision And Unroofing History Of The Himalayan Orogen Using Detrital Zircon U-Pb-Hf And Whole-Rock Sr-Nd Isotopes In Cretaceous-Miocene Lesser Himalayan Sedimentary Rocks, Wei Feng, Qingquan Meng, Chunhui Song, Xiaomin Fang, Guangsheng Zhuang, Pengju He, Shufen Yang, Jing Zhang, Yongfa Chen, Yihu Zhang

Faculty Publications

Cretaceous-Miocene sedimentary rocks in the Nepalese Lesser Himalaya provide an opportunity to decipher the timing of India-Asia collision and unroofing history of the Himalayan orogen, which are significant for understanding the growth processes of the Himalayan-Tibetan orogen. Our new data indicate that detrital zircon ages and whole-rock Sr-Nd isotopes in Cretaceous-Miocene Lesser Himalayan sedimentary rocks underwent two significant changes. First, from the Upper Cretaceous-Palaeocene Amile Formation to the Eocene Bhainskati Formation, the proportion of late Proterozoic-early Palaeozoic zircons (quantified by an index of 500–1200 Ma/1600–2800 Ma) increased from nearly 0 to 0.7–1.4, and the percentage of Mesozoic zircons decreased from …


Thermoset Polymer Composites With Gradient Natural And Synthetic Fiber Reinforcement: Self-Healing, Shape-Memory, And Fiber Recyclability, Sakil Mahmud, John Konlan, Jenny Deicaza, Rachel Anna Schmidt, Guoqiang Li Jun 2023

Thermoset Polymer Composites With Gradient Natural And Synthetic Fiber Reinforcement: Self-Healing, Shape-Memory, And Fiber Recyclability, Sakil Mahmud, John Konlan, Jenny Deicaza, Rachel Anna Schmidt, Guoqiang Li

Faculty Publications

Natural fibers have high potential as renewable reinforcement for polymers; however, their lower load-carrying capacity compared to synthetic fibers significantly limits the wide application in fiber-reinforced polymer composites. In laminated composite beams under bending load, the normal stress is the highest on the top and bottom layers but is zero at the mid-plane, with almost a linear normal strain distribution. Although the shear stress is the highest at the mid-plane, it may not be a major concern as most polymers can survive the high shear stress. Using this concept, we have designed a hybrid fiber reinforcement in a gradient manner: …


On The Characteristics Of Fatigue Fracture With Rapid Frequency Change, Mohammad A. Amooie, K. P. Lijesh, Ali Mahmoudi, Elaheh Azizian-Farsani, Michael M. Khonsari Jun 2023

On The Characteristics Of Fatigue Fracture With Rapid Frequency Change, Mohammad A. Amooie, K. P. Lijesh, Ali Mahmoudi, Elaheh Azizian-Farsani, Michael M. Khonsari

Faculty Publications

The effect of sudden variations in working modes and fatigue behavior of CS 1018 is studied. A general model based on the framework of the fracture fatigue entropy (FFE) concept is developed to capture such changes. Fully reversed bending tests are performed on flat dog bone specimens with a series of variable frequency tests without turning the machine off to simulate fluctuating working conditions. The results are then post-processed and analyzed to assess how fatigue life changes when a component is subjected to sudden changes in multiple frequencies. It is demonstrated that regardless of the frequency changes, FFE remains constant …


Feature Extraction Techniques For Noisy Distributed Acoustic Sensor Data Acquired In A Wellbore, Jagadeeshwar Tabjula, Jyotsna Sharma Jun 2023

Feature Extraction Techniques For Noisy Distributed Acoustic Sensor Data Acquired In A Wellbore, Jagadeeshwar Tabjula, Jyotsna Sharma

Faculty Publications

The distributed acoustic sensor (DAS) is a promising technology for real-time monitoring of wellbores and other infrastructures. However, the desired signals are often overwhelmed by background and environmental noise inherent in field applications. We present a suite of computationally inexpensive techniques for the real-time extraction of the gas signatures from noisy DAS data acquired in a 5163 ft. deep wellbore. The techniques are implemented on three well-scale DAS datasets, each representing multiphase flow conditions with different gas injection volumes, fluid circulation rates, and injection methods. The proposed denoising techniques not only helped in optimizing the gas slug signature despite the …


Contrasting Responses Of Atlantic And Pacific Tropical Cyclone Activity To Atlantic Multidecadal Variability, Huanping Huang, William D. Collins, Christina M. Patricola, Yohan Ruprich-Robert, Paul A. Ullrich, Alexander J. Baker May 2023

Contrasting Responses Of Atlantic And Pacific Tropical Cyclone Activity To Atlantic Multidecadal Variability, Huanping Huang, William D. Collins, Christina M. Patricola, Yohan Ruprich-Robert, Paul A. Ullrich, Alexander J. Baker

Faculty Publications

This research assesses the influences of Atlantic Multidecadal Variability (AMV) on global tropical cyclones (TCs) using two large ensembles of idealized global climate model simulations with opposite signs of AMV forcings superimposed (i.e., AMV+ and AMV–). We first detect TCs and then compare TC activity by basin in the two AMV experiments. We find contrasting responses of Atlantic and Pacific TC frequency to the AMV anomalies. Compared to AMV–, AMV+ significantly increases TC frequency in the North Atlantic, including those making landfalls. The increase is explained by warmer sea surface temperature, higher relative humidity, increased relative vorticity, and weaker vertical …


Silica Concentrations In Dominant Vegetation Species Of Wax Lake Delta, Louisiana, Danielle M. Soileau May 2023

Silica Concentrations In Dominant Vegetation Species Of Wax Lake Delta, Louisiana, Danielle M. Soileau

LSU Master's Theses

Coastal deltaic wetlands colonize dynamic environments and experience fluctuations of salinity, river connectivity, sediment dredging or deposition, and periods of inundation resulting in unique vegetation and soils. Louisiana’s coastline is experiencing enhanced loss of coastal deltaic wetlands in coastal basins where the Mississippi River no longer is connected to waterways and channels that would normally provide freshwater and sediments representing the abandonment phase of the delta cycle. There is a coastal basin in the central regions of the state, the Atchafalaya Bay, that is still in the active phase of delta cycle resulting in the growth of the Wax Lake, …


Ecology Of Viruses In Marine And Coastal Oxygen-Depleted Waters, Sophie Jurgensen May 2023

Ecology Of Viruses In Marine And Coastal Oxygen-Depleted Waters, Sophie Jurgensen

LSU Doctoral Dissertations

Deoxygenation of marine and coastal waters, both caused and exacerbated by a suite of abiotic and biotic factors, has been documented for more than sixty years. The incidence and severity of low-oxygen areas is predicted to expand globally in the coming decades. Despite their colloquial moniker “dead zones,” low-oxygen areas contain thriving and diverse microorganisms that have significant impacts on global biogeochemical cycles including contributing to positive feedback loops that further expand low-oxygen areas. While the diversity and activity of these microorganisms is beginning to be elucidated, the ecology of their viruses is particularly understudied. In this dissertation, I present …


The Coralhydro2k Database: A Global, Actively Curated Compilation Of Coral Δ18o And Sr/Ca Proxy Records Of Tropical Ocean Hydrology And Temperature For The Common Era, Rachel M. Walter, Hussein R. Sayani, Thomas Felis, Kim M. Cobb, Nerilie J. Abram, Ariella K. Arzey, Alyssa R. Atwood, Logan D. Brenner, Émilie P. Dassié, Kristine L. Delong, Bethany Ellis, Julien Emile-Geay, Matthew J. Fischer, Nathalie F. Goodkin, Jessica A. Hargreaves, K. Halimeda Kilbourne, Hedwig Krawczyk, Nicholas P. Mckay, Andrea L. Moore, Sujata A. Murty, Maria Rosabelle Ong, Riovie D. Ramos, Emma V. Reed, Dhrubajyoti Samanta, Sara C. Sanchez, Jens Zinke May 2023

The Coralhydro2k Database: A Global, Actively Curated Compilation Of Coral Δ18o And Sr/Ca Proxy Records Of Tropical Ocean Hydrology And Temperature For The Common Era, Rachel M. Walter, Hussein R. Sayani, Thomas Felis, Kim M. Cobb, Nerilie J. Abram, Ariella K. Arzey, Alyssa R. Atwood, Logan D. Brenner, Émilie P. Dassié, Kristine L. Delong, Bethany Ellis, Julien Emile-Geay, Matthew J. Fischer, Nathalie F. Goodkin, Jessica A. Hargreaves, K. Halimeda Kilbourne, Hedwig Krawczyk, Nicholas P. Mckay, Andrea L. Moore, Sujata A. Murty, Maria Rosabelle Ong, Riovie D. Ramos, Emma V. Reed, Dhrubajyoti Samanta, Sara C. Sanchez, Jens Zinke

Faculty Publications

The response of the hydrological cycle to anthropogenic climate change, especially across the tropical oceans, remains poorly understood due to the scarcity of long instrumental temperature and hydrological records. Massive shallow-water corals are ideally suited to reconstructing past oceanic variability as they are widely distributed across the tropics, rapidly deposit calcium carbonate skeletons that continuously record ambient environmental conditions, and can be sampled at monthly to annual resolution. Climate reconstructions based on corals primarily use the stable oxygen isotope composition (δ18O), which acts as a proxy for sea surface temperature (SST), and the oxygen isotope composition of seawater (δ18Osw), a …


Experiments And Data Analysis For Modulated Phase Gratings In X-Rays, Sydney B. Carr May 2023

Experiments And Data Analysis For Modulated Phase Gratings In X-Rays, Sydney B. Carr

LSU Master's Theses

Purpose: Modulated Phase Grating (MPG) interferometry has been shown in theory and simulations to produce observable fringes on a clinical detector without requiring fluence absorbing analyzer. In this work, we will experimentally show that the MPG X-ray system produces observable fringes and multi-modal X-ray images.

Motivation:Nearly 1 in 8 women in the US will develop invasive breast cancer in their lifetime, accounting for approximately 40,000 deaths each year [1-2]. In order to pursue the best treatment option available, cancer itself must be adequately imaged and staged, based on size and level of metastasis, on the order of Stage I-IV. …