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Smart3pm: Smart Pavement Monitoring, Management, And Maintenance, Damien Stephens, Mena Souliman, Mukul Shirvaikar, Samer Dessouky Jan 2024

Smart3pm: Smart Pavement Monitoring, Management, And Maintenance, Damien Stephens, Mena Souliman, Mukul Shirvaikar, Samer Dessouky

Publications

An application specific multi-platform smartphone application can utilize on-board accelerometer, gyroscope, and GPS sensors, along with software derived signals from the same sensors, to sample vibrational and geolocation datasets to capture pavement distresses such as potholes when mounted in a standardized configuration in a vehicle. Several observations were made with regard to the signals obtained from the accelerometer, gyroscope, and GPS sensors, and it was determined that the raw sensor outputs are capable of sampling statistically significant datasets which can be used to distinguish pavement distress from normal driving conditions. Furthermore, an approximate sensor noise margin is established, and a …

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Design Of 3d Printable Eco-Concrete By Utilizing Rheology Modifiers For Sustainable Infrastructure, Maryam Hojati, Muhammad Saeed Zafar Jan 2024

Design Of 3d Printable Eco-Concrete By Utilizing Rheology Modifiers For Sustainable Infrastructure, Maryam Hojati, Muhammad Saeed Zafar

Publications

In recent years, 3D printing technology has gained significant momentum across various industries within the construction sector, 3D printing has emerged as a promising technique; however, there are challenges associated with designing suitable construction materials and adjusting their properties for the 3D printing process. One of the key considerations in this regard is the rheological properties, encompassing parameters such as viscosity, yield stress, and thixotropy. These properties play a pivotal role in shaping the characteristics of 3D-printed concrete, both in its fresh and hardened states, including buildability, extrudability, and mechanical performance. Researchers have traditionally relied on chemical admixtures, such as …

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Development Of A Web Application For Traffic Accident Mapping And Analysis, Susan Bogus Halter, Su Zhang, Arian Golrokh Amin Jan 2024

Development Of A Web Application For Traffic Accident Mapping And Analysis, Susan Bogus Halter, Su Zhang, Arian Golrokh Amin

Publications

It is widely accepted that road traffic safety is a significant public health issue. One of the effective ways to improve road traffic safety is analyzing crash data to understand where traffic accidents occur, identify associated spatial and temporal patterns, and determine causation. In the State of New Mexico, locations of traffic accidents are currently visualized using a variety of static maps. Although these statics maps are easier to create and producers can control how users view the data, users cannot customize these maps to meet their special needs. That being said, new maps need to be created for any …

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Motorcycle Crash Analysis, Hatim Sharif, Samer Dessouky Jan 2024

Motorcycle Crash Analysis, Hatim Sharif, Samer Dessouky

Publications

The Fatality Analysis Reporting System database shows that, in stark contrast to the 34 percent decline in non-motorcyclist crash–related fatalities, motorcyclist crash–related fatalities were up 86 percent with only three year-to-year declines since 1997, while non-motorcyclist crash–related fatalities had 13 year-to-year declines since 1997. At the national level, the rate of motorcyclist fatalities per vehicle mile traveled is 29 times higher than the rate among passenger car occupants, with overall injury rates approximately five times higher among motorcyclists than passenger car occupants. Given the frequency of motorcycle crashes and their staggering toll in terms of loss of life and economic …

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Bridge Inspection Training And Enhanced Operations Using Augmented Reality, Fernando Moreu, Ali Mohammadkhorasani, Kaveh Malek Jan 2024

Bridge Inspection Training And Enhanced Operations Using Augmented Reality, Fernando Moreu, Ali Mohammadkhorasani, Kaveh Malek

Publications

This research project focused on the innovative application of Augmented Reality (AR) headsets to enhance bridge inspection processes and inspection training. The study encompassed the visualization of 3D point cloud data, utilized the Eye-Tracking features of AR headsets for inspection quantification, evaluate the applicability of AR in the bridge inspection training and instruction of an AR virtual menu for the in-field bridge inspection. The primary tasks included establishing a database connection for AR headset, designing an AR menu tailored for bridge inspection, devising an evaluation method based on Eye-Tracking capabilities, and integrating AR into bridge inspection training. Once the technical …

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Deep Reinforcement Learning-Based Digital Twin For Risk Improved Decision Making In Transportation Construction, Yong-Cheol Lee, Anisha Deria Jan 2024

Deep Reinforcement Learning-Based Digital Twin For Risk Improved Decision Making In Transportation Construction, Yong-Cheol Lee, Anisha Deria

Publications

Organizing and overseeing a large number of transportation construction and maintenance projects that generally entail several miles of a worksite are a critical burden for each DOT. In addition, it requires manual monitoring of a project or construction managers to identify a progress status, a work activity, and a safety issue in a job site. Because of the projected huge volume, complexity, significant impacts of future transportation infrastructure projects, it is evident that we are now facing a critical need to create a means of improving the results of work zone management and evaluating their impacts on our society. In …

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The Effect Of Covid-19 Lockdown On Traffic Crashes In Texas., Hatim Sharif, Samer Dessouky Jan 2024

The Effect Of Covid-19 Lockdown On Traffic Crashes In Texas., Hatim Sharif, Samer Dessouky

Publications

An analysis of traffic patterns during COVID-19 has identified that reduction in the miles traveled has a significant negative correlation with COVID-19 cases and deaths across the USA. Preliminary statistics in the US suggest an increase in fatal crashes over the period of the lockdown in comparison to the same period in previous years. Moreover, while total crashes are down, motor vehicle crashes involving non-motorists became more prevalent. At the same time, non-motorist traffic has increased while motor vehicle traffic and crashes have shifted to the local systems. The main goal of this research is to perform a comprehensive evaluation …

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Calcined Clays As Alternative Supplementary Cementitious Material And Precursor For Geopolymer Binders In Transportation Infrastructure, Hassan Noorvand, Miladin Radovic, Marwa Hassan, Adriana A. Alvarado, Oscar Huang Jan 2024

Calcined Clays As Alternative Supplementary Cementitious Material And Precursor For Geopolymer Binders In Transportation Infrastructure, Hassan Noorvand, Miladin Radovic, Marwa Hassan, Adriana A. Alvarado, Oscar Huang

Publications

This project aimed to assess the feasibility of using locally sourced calcined kaolinitic clays both as supplementary cementitious materials (SCMs) and as precursors for synthesizing geopolymers (GPs). For SCMs, a comprehensive set of characterizations was conducted, including X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), particle size analysis, and loss on ignition (LOI), along with evaluations of concrete properties such as strength activity index (SAI), slump, air content, compressive strength, and surface resistivity. For GPs, compressive strength was tested. The study yielded several key findings: (1) Three types of calcined clays (CCs) were analyzed based …

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Prediction Of Moisture Resistance Of Polymeric Asphalt Binders Through The Atomic Force Microscopy (Afm) Technique, Zahid Hossain, Ashraf Elsayed, Khaja Sameer Sadat Jan 2024

Prediction Of Moisture Resistance Of Polymeric Asphalt Binders Through The Atomic Force Microscopy (Afm) Technique, Zahid Hossain, Ashraf Elsayed, Khaja Sameer Sadat

Publications

Moisture damage is a significant concern for state Departments of Transportation (DOTs) and other agencies due to its adverse impact on pavement performance as well as longevity. The main focus of the current study project is to quantify, at the molecular level, the interaction between binder and aggregate at the interface level in the form of adhesion forces between bitumen samples and minerals of various chemical compositions. First of all, A thorough review of the literature on moisture degradation in asphalts was conducted. Based on the literature review, a comprehensive project plan and test matrix were created. Binder samples from …

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Early-Age Strength Monitoring Of Sensor-Embedded 3d Printed Structures, Ali Kazemian, Marwa Hassan, Hassan Noorvand, Gabriel Arce, Kasra Banijamali Jan 2024

Early-Age Strength Monitoring Of Sensor-Embedded 3d Printed Structures, Ali Kazemian, Marwa Hassan, Hassan Noorvand, Gabriel Arce, Kasra Banijamali

Publications

Construction 3D printing (C3DP) is an automated technology that has the potential to reduce the construction time and cost by utilizing different types of robotic systems. Due to the absence of formwork in C3DP, potential excessive water evaporation can cause issues to the freshly-printed structures that are exposed to the ambient curing condition. Moreover, the 3D printed elements should carry the service loads in a short time after printing to provide a load-bearing capacity. Destructive and non-destructive methods are the two types of methods that are being used in the construction industry for quality monitoring. Due to the time-consuming nature …

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Miocene Climatic Optimum Fungal Record And Plant-Based Crest Climatic Reconstruction From Southern Mcmurdo Sound, Antarctica, Mallory Pilie, Martha E. Gibson, Ingrid C. Romero, Noelia B.Nuñez Otaño, Matthew J. Pound, Jennifer M.K. O'Keefe, Sophie Warny Dec 2023

Miocene Climatic Optimum Fungal Record And Plant-Based Crest Climatic Reconstruction From Southern Mcmurdo Sound, Antarctica, Mallory Pilie, Martha E. Gibson, Ingrid C. Romero, Noelia B.Nuñez Otaño, Matthew J. Pound, Jennifer M.K. O'Keefe, Sophie Warny

Faculty Publications

Deep-time palynological studies are necessary to evaluate plant and fungal distribution under warmer-than-present scenarios such as those of the Middle Miocene. Previous palynological studies from southern McMurdo Sound, Antarctica (SMS), have provided unique documentation for Neogene environments in the Ross Sea region during a time of pronounced global warming. The present study builds on these studies and provides a new climate reconstruction using the previously published SMS pollen and plant spore data. Additionally, 44 SMS samples were reanalyzed with a focus on the fungal fraction of the section to evaluate the fungal distribution under warmer than present conditions. The probability-based …

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Environmental Dna (Edna) Removal Rates In Streams Differ By Particle Size Under Varying Substrate And Light Conditions, Elise D. Snyder, Jennifer L. Tank, Pedro F.P. Brandão-Dias, Kyle Bibby, Arial J. Shogren, Aaron W. Bivins, Brett Peters, Erik M. Curtis, Diogo Bolster, Scott P. Egan, Gary A. Lamberti Dec 2023

Environmental Dna (Edna) Removal Rates In Streams Differ By Particle Size Under Varying Substrate And Light Conditions, Elise D. Snyder, Jennifer L. Tank, Pedro F.P. Brandão-Dias, Kyle Bibby, Arial J. Shogren, Aaron W. Bivins, Brett Peters, Erik M. Curtis, Diogo Bolster, Scott P. Egan, Gary A. Lamberti

Faculty Publications

The use of environmental DNA (eDNA) as a sampling tool offers insights into the detection of invasive and/or rare aquatic species and enables biodiversity assessment without traditional sampling approaches, which are often labor-intensive. However, our understanding of the environmental factors that impact eDNA removal (i.e., how rapidly eDNA is removed from the water column by the combination of decay and physical removal) in flowing waters is limited. This limitation constrains predictions about the location and density of target organisms after positive detection. To address this question, we spiked Common Carp (Cyprinus carpio) eDNA into recirculating mesocosms (n = 24) under …

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The Concept Of Land Bridge Marshes In The Mississippi River Delta And Implications For Coastal Restoration, John W. Day, Robert R. Twilley, Angelina Freeman, Brady Couvillion, Tracy Quirk, Navid Jafari, Giulio Mariotti, Rachael Hunter, Charles Norman, G. Paul Kemp, John R. White, Ehab Meselhe Dec 2023

The Concept Of Land Bridge Marshes In The Mississippi River Delta And Implications For Coastal Restoration, John W. Day, Robert R. Twilley, Angelina Freeman, Brady Couvillion, Tracy Quirk, Navid Jafari, Giulio Mariotti, Rachael Hunter, Charles Norman, G. Paul Kemp, John R. White, Ehab Meselhe

Faculty Publications

Louisiana has high coastal wetland loss rates due to natural processes such as subsidence and anthropogenic activities such as construction of river levees and dams, pervasive alteration of surface hydrology by local industries such as oil and gas, and navigation. With the exception of the Atchafalaya River discharge area, most of Louisiana's marsh coastline is retreating and coastal marshes are degrading. In the inactive degrading delta regions, there exists a previously uncharacterized landform referred to colloquially as coastal ‘land bridge’ marshes. Land bridge marshes are saline or brackish marshes fronting large estuarine bays or lakes with sufficient fetch and wave …

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Atmospheric Flash Drought In The Caribbean, Craig A. Ramseyer, Paul W. Miller Dec 2023

Atmospheric Flash Drought In The Caribbean, Craig A. Ramseyer, Paul W. Miller

Faculty Publications

Despite the intensifying interest in flash drought both within the United States and globally, moist tropical landscapes have largely escaped the attention of the flash drought community. Because these ecozones are acclimatized to receiving regular, near-daily precipitation, they are especially vulnerable to rapid-drying events. This is particularly true within the Caribbean Sea basin where numerous small islands lack the surface and groundwater resources to cope with swiftly developing drought conditions. This study fills the tropical flash drought gap by examining the pervasiveness of flash drought across the pan-Caribbean region using a recently proposed criterion based on the evaporative demand drought …

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Soil Legacy Nutrients Contribute To The Decreasing Stoichiometric Ratio Of N And P Loading From The Mississippi River Basin, Zihao Bian, Hanqin Tian, Shufen Pan, Hao Shi, Chaoqun Lu, Christopher Anderson, Wei Jun Cai, Charles S. Hopkinson, Dubravko Justic, Latif Kalin, Steven Lohrenz, Steven Mcnulty, Naiqing Pan, Ge Sun, Zhuonan Wang, Yuanzhi Yao, Yongfa You Dec 2023

Soil Legacy Nutrients Contribute To The Decreasing Stoichiometric Ratio Of N And P Loading From The Mississippi River Basin, Zihao Bian, Hanqin Tian, Shufen Pan, Hao Shi, Chaoqun Lu, Christopher Anderson, Wei Jun Cai, Charles S. Hopkinson, Dubravko Justic, Latif Kalin, Steven Lohrenz, Steven Mcnulty, Naiqing Pan, Ge Sun, Zhuonan Wang, Yuanzhi Yao, Yongfa You

Faculty Publications

Human-induced nitrogen–phosphorus (N, P) imbalance in terrestrial ecosystems can lead to disproportionate N and P loading to aquatic ecosystems, subsequently shifting the elemental ratio in estuaries and coastal oceans and impacting both the structure and functioning of aquatic ecosystems. The N:P ratio of nutrient loading to the Gulf of Mexico from the Mississippi River Basin increased before the late 1980s driven by the enhanced usage of N fertilizer over P fertilizer, whereafter the N:P loading ratio started to decrease although the N:P ratio of fertilizer application did not exhibit a similar trend. Here, we hypothesize that different release rates of …

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Early Effects Of The Emergency Rental Assistance Program: Evidence From A Natural Experiment, Logan Kern Dec 2023

Early Effects Of The Emergency Rental Assistance Program: Evidence From A Natural Experiment, Logan Kern

Honors Capstones

No abstract provided.

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The Influence Of Salinity And Vegetation Texture On The Ecological Roles Of Insects In Tidal Marshes In Louisiana, Benjamin G. Aker, Claudia Husseneder, Lane D. Foil Dec 2023

The Influence Of Salinity And Vegetation Texture On The Ecological Roles Of Insects In Tidal Marshes In Louisiana, Benjamin G. Aker, Claudia Husseneder, Lane D. Foil

Faculty Publications

Tidal marsh insect communities are influenced by both salinity and aspects of vegetation texture (vegetation diversity, plant density, and architectural structure). These factors affect the abundances and intra- and interguild interactions of these insects and should result in broad-scale variation in the distribution and ecological functioning of tidal marsh insect communities along these gradients. However, this assumption has not been tested within Gulf Coast marshes, and the insect communities and their ecological roles are not well known. This study identifies how family-level insect biodiversity varies by salinity and which factors are most important in affecting the distribution of insect functional …

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Building Resilience To Extreme Weather And Climate Events In The Rural Water And Wastewater Sectors, Nathan P. Kettle, Sarah F. Trainor, Renee Edwards, Donald Antrobus, Curt Baranowski, Tina Buxbaum, Kevin Berry, Michael Brubaker, Kristine L. De Long, Steve Fries, Davin Holen, Barry Keim, Danielle Meeker, Harry Penn, Cheryl Rosa, Rick Thoman, John Walsh, Jian Zhang Dec 2023

Building Resilience To Extreme Weather And Climate Events In The Rural Water And Wastewater Sectors, Nathan P. Kettle, Sarah F. Trainor, Renee Edwards, Donald Antrobus, Curt Baranowski, Tina Buxbaum, Kevin Berry, Michael Brubaker, Kristine L. De Long, Steve Fries, Davin Holen, Barry Keim, Danielle Meeker, Harry Penn, Cheryl Rosa, Rick Thoman, John Walsh, Jian Zhang

Faculty Publications

Extreme weather and climate events pose significant risks to rural water and wastewater systems. We examine the vulnerability of the water sector to weather and climate extremes in rural, predominantly Indigenous and underserved coastal areas and analyze how networks support resilience. Drawing on the analysis of 39 web-based questionnaire responses and 19 interviews with rural water and wastewater managers and service providers in southern Louisiana and western Alaska, this article reports a range of interrelated historical, environmental, and social factors that influence vulnerability to extreme weather events. Formal and informal social networks serve multiple roles in building resilience. These roles …

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Mechanical And Thermal Properties Of Mud Dauber Nests Under Atmospheric Drying, Joon S. Park, Hai Lin, Hussein Alqrinawi Dec 2023

Mechanical And Thermal Properties Of Mud Dauber Nests Under Atmospheric Drying, Joon S. Park, Hai Lin, Hussein Alqrinawi

Faculty Publications

Mud dauber wasps construct soil nests to protect their offspring from predators, extreme temperatures, and rainwater. The mechanical and thermal properties of these nests are important for the reproductive success of mud daubers. The previous study showed that the high densities and strengths of mud dauber nests were due to the repetitive tapping and atmospheric drying used by mud daubers during nest construction. This study investigated the effect of atmospheric drying on the mechanical and thermal properties of mud dauber nests. The soil shrinkage curve, elastic modulus, suction stress characteristic curve, soil water retention curve, shear strength, and thermal conductivity …

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Modeling Of Cryopreservation Pathway Operation At An Aquatic Biomedical Stock Center For Zebrafish, Sarah Bodenstein, Fidan Abdullayeva, Joy M. Murphy, Zoltan M. Varga, Terrence R. Tiersch Dec 2023

Modeling Of Cryopreservation Pathway Operation At An Aquatic Biomedical Stock Center For Zebrafish, Sarah Bodenstein, Fidan Abdullayeva, Joy M. Murphy, Zoltan M. Varga, Terrence R. Tiersch

Faculty Publications

Aquatic biomedical model organisms play a substantial role in advancing our understanding of human health, however, comparably little work has been directed towards developing dependable, high-throughput storage programs for valuable genetic resources. The Zebrafish International Resource Center (ZIRC) has developed a standardized cryopreservation pathway and stored thousands of genetic lines in their repository for use by the biomedical research community. This has yet to be replicated in other facilities, and an overall repository-level pathway has never been analyzed for aquatic species. To encourage repository development for other biomedical models and to improve the ZIRC storage process and system, this study …

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Dietary Intake During A Pragmatic Cluster-Randomized Weight Loss Trial In An Underserved Population In Primary Care, John W. Apolzan, Corby K. Martin, Robert L. Newton, Candice A. Myers, Connie L. Arnold, Terry C. Davis, William D. Johnson, Dachuan Zhang, Christoph Höchsmann, Vivian A. Fonseca, Kara D. Denstel, Emily F. Mire, Benjamin F. Springgate, Carl J. Lavie, Peter T. Katzmarzyk, Phillip Brantley, Ronald Horswell, Tina K. Thethi, Jonathan Gugel, Eboni Price-Haywood, Kathleen B. Kennedy, Daniel F. Sarpong Dec 2023

Dietary Intake During A Pragmatic Cluster-Randomized Weight Loss Trial In An Underserved Population In Primary Care, John W. Apolzan, Corby K. Martin, Robert L. Newton, Candice A. Myers, Connie L. Arnold, Terry C. Davis, William D. Johnson, Dachuan Zhang, Christoph Höchsmann, Vivian A. Fonseca, Kara D. Denstel, Emily F. Mire, Benjamin F. Springgate, Carl J. Lavie, Peter T. Katzmarzyk, Phillip Brantley, Ronald Horswell, Tina K. Thethi, Jonathan Gugel, Eboni Price-Haywood, Kathleen B. Kennedy, Daniel F. Sarpong

Clinical Research Faculty Publications

Background: Currently there are limited data as to whether dietary intake can be improved during pragmatic weight loss interventions in primary care in underserved individuals. Methods: Patients with obesity were recruited into the PROPEL trial, which randomized 18 clinics to either an intensive lifestyle intervention (ILI) or usual care (UC). At baseline and months 6, 12, and 24, fruit and vegetable (F/V) intake and fat intake was determined. Outcomes were analyzed by repeated-measures linear mixed-effects multilevel models and regression models, which included random cluster (clinic) effects. Secondary analyses examined the effects of race, sex, age, and food security status. Results: …

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Physiologic Hormone Administration Improves Hba1c In Native Americans With Type 2 Diabetes: A Retrospective Study And Review Of Insulin Secretion And Action, Candida J. Rebello, Tyler S. Morales, Katsya Chuon, Shu Dong, V. Tyrone Lam, Dan Purner, Stanley Lewis, Jonathan Lakey, Robbie A. Beyl, Frank L. Greenway Dec 2023

Physiologic Hormone Administration Improves Hba1c In Native Americans With Type 2 Diabetes: A Retrospective Study And Review Of Insulin Secretion And Action, Candida J. Rebello, Tyler S. Morales, Katsya Chuon, Shu Dong, V. Tyrone Lam, Dan Purner, Stanley Lewis, Jonathan Lakey, Robbie A. Beyl, Frank L. Greenway

Clinical Research Faculty Publications

Insulin is secreted in pulses from pancreatic beta-cells, and these oscillations maintain fasting plasma glucose levels within a narrow normal range. Within islets, beta-cells exhibit tight synchronization of regular oscillations. This control circuit is disrupted in type 2 diabetes, and irregularities in pulse frequency and amplitude occur. The prevalence of type 2 diabetes is three times higher in American Indian and Native Alaskans compared to Whites, and their genetic ancestry is associated with low beta-cell function. Obesity in this population compounds their vulnerability to adverse outcomes. The purpose of this article is to review insulin secretion and action and its …

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Global Dataset Of Soil Organic Carbon In Tidal Marshes, Tania L. Maxwell, André S. Rovai, Maria Fernanda Adame, Janine B. Adams, José Álvarez-Rogel, William E.N. Austin, Kim Beasy, Francesco Boscutti, Michael E. Böttcher, Tjeerd J. Bouma, Richard H. Bulmer, Annette Burden, Shannon A. Burke, Saritta Camacho, Doongar R. Chaudhary, Gail L. Chmura, Margareth Copertino, Grace M. Cott, Christopher Craft, John Day, Carmen B. De Los Santos, Lionel Denis, Weixin Ding, Joanna C. Ellison, Carolyn J. Ewers Lewis, Luise Giani, Maria Gispert, Swanne Gontharet, José A. González-Pérez, M. Nazaret González-Alcaraz, Connor Gorham, Anna Elizabeth L. Graversen, Anthony Grey Dec 2023

Global Dataset Of Soil Organic Carbon In Tidal Marshes, Tania L. Maxwell, André S. Rovai, Maria Fernanda Adame, Janine B. Adams, José Álvarez-Rogel, William E.N. Austin, Kim Beasy, Francesco Boscutti, Michael E. Böttcher, Tjeerd J. Bouma, Richard H. Bulmer, Annette Burden, Shannon A. Burke, Saritta Camacho, Doongar R. Chaudhary, Gail L. Chmura, Margareth Copertino, Grace M. Cott, Christopher Craft, John Day, Carmen B. De Los Santos, Lionel Denis, Weixin Ding, Joanna C. Ellison, Carolyn J. Ewers Lewis, Luise Giani, Maria Gispert, Swanne Gontharet, José A. González-Pérez, M. Nazaret González-Alcaraz, Connor Gorham, Anna Elizabeth L. Graversen, Anthony Grey

Faculty Publications

Tidal marshes store large amounts of organic carbon in their soils. Field data quantifying soil organic carbon (SOC) stocks provide an important resource for researchers, natural resource managers, and policy-makers working towards the protection, restoration, and valuation of these ecosystems. We collated a global dataset of tidal marsh soil organic carbon (MarSOC) from 99 studies that includes location, soil depth, site name, dry bulk density, SOC, and/or soil organic matter (SOM). The MarSOC dataset includes 17,454 data points from 2,329 unique locations, and 29 countries. We generated a general transfer function for the conversion of SOM to SOC. Using this …

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Deep Learning For Enhanced Free-Space Optical Communications, M. P. Bart, N. J. Savino, P. Regmi, L. Cohen, H. Safavi, H. C. Shaw, S. Lohani, T. A. Searles, B. T. Kirby, H. Lee, R. T. Glasser Dec 2023

Deep Learning For Enhanced Free-Space Optical Communications, M. P. Bart, N. J. Savino, P. Regmi, L. Cohen, H. Safavi, H. C. Shaw, S. Lohani, T. A. Searles, B. T. Kirby, H. Lee, R. T. Glasser

Faculty Publications

Atmospheric effects, such as turbulence and background thermal noise, inhibit the propagation of light used in ON-OFF keying (OOK) free-space optical (FSO) communication. Here we present and experimentally validate a convolutional neural network (CNN) to reduce the bit error rate of FSO communication in post-processing that is significantly simpler and cheaper than existing solutions based on advanced optics. Our approach consists of two neural networks, the first determining the presence of bit sequences in thermal noise and turbulence and the second demodulating the bit sequences. All data used for training and testing our network is obtained experimentally by generating OOK …

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Multiphoton Quantum Van Cittert-Zernike Theorem, Chenglong You, Ashe Miller, Roberto De J. León-Montiel, Omar S. Magaña-Loaiza Dec 2023

Multiphoton Quantum Van Cittert-Zernike Theorem, Chenglong You, Ashe Miller, Roberto De J. León-Montiel, Omar S. Magaña-Loaiza

Faculty Publications

Recent progress on quantum state engineering has enabled the preparation of quantum photonic systems comprising multiple interacting particles. Interestingly, multiphoton quantum systems can host many complex forms of interference and scattering processes that are essential to perform operations that are intractable on classical systems. Unfortunately, the quantum coherence properties of multiphoton systems degrade upon propagation leading to undesired quantum-to-classical transitions. Furthermore, the manipulation of multiphoton quantum systems requires nonlinear interactions at the few-photon level. Here, we introduce the quantum van Cittert-Zernike theorem to describe the scattering and interference effects of propagating multiphoton systems. This fundamental theorem demonstrates that the quantum …

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Cells Collectively Migrate During Ammonium Chemotaxis In Chlamydomonas Reinhardtii, Gabela Nelson, Alexis Strain, Atsuko Isu, Alireza Rahnama, Ken Ichi Wakabayashi, Adam T. Melvin, Naohiro Kato Dec 2023

Cells Collectively Migrate During Ammonium Chemotaxis In Chlamydomonas Reinhardtii, Gabela Nelson, Alexis Strain, Atsuko Isu, Alireza Rahnama, Ken Ichi Wakabayashi, Adam T. Melvin, Naohiro Kato

Faculty Publications

The mechanisms governing chemotaxis in Chlamydomonas reinhardtii are largely unknown compared to those regulating phototaxis despite equal importance on the migratory response in the ciliated microalga. To study chemotaxis, we made a simple modification to a conventional Petri dish assay. Using the assay, a novel mechanism governing Chlamydomonas ammonium chemotaxis was revealed. First, we found that light exposure enhances the chemotactic response of wild-type Chlamydomonas strains, yet phototaxis-incompetent mutant strains, eye3-2 and ptx1, exhibit normal chemotaxis. This suggests that Chlamydomonas transduces the light signal pathway in chemotaxis differently from that in phototaxis. Second, we found that Chlamydomonas collectively migrate during …

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Mid-Miocene Sea Level Altitude Of The Qaidam Basin, Northern Tibetan Plateau, Yuanyuan Sun, Yu Liang, Hu Liu, Jun Liu, Junliang Ji, Xue Ke, Xiaobo Liu, Yuxin He, Huanye Wang, Bin Zhang, Yongsu Zhang, Guangsheng Zhuang, Junling Pei, Yongxiang Li, Cheng Quan, Jianxing Li, Jonathan C. Aitchison, Weiguo Liu, Zhonghui Liu Dec 2023

Mid-Miocene Sea Level Altitude Of The Qaidam Basin, Northern Tibetan Plateau, Yuanyuan Sun, Yu Liang, Hu Liu, Jun Liu, Junliang Ji, Xue Ke, Xiaobo Liu, Yuxin He, Huanye Wang, Bin Zhang, Yongsu Zhang, Guangsheng Zhuang, Junling Pei, Yongxiang Li, Cheng Quan, Jianxing Li, Jonathan C. Aitchison, Weiguo Liu, Zhonghui Liu

Faculty Publications

A detailed uplift history of the Tibetan Plateau is essential for disentangling the proposed geodynamical models and assessing its impacts on climate and biodiversity. However, when and how the plateau formed remains highly controversial. Here, we present unusual geochemical indicators of marine signatures in the Cenozoic terrestrial strata of the Qaidam Basin, northern Tibetan Plateau, with strong implications for the basin altitude. Our investigations across the basin reveal typical marine alkenones and anomalously high carbonate carbon isotopic values during the mid-Miocene, but not at earlier stages, which are accompanied by a divergent trend in the paired carbonate oxygen and leaf …

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Morphodynamic Modeling Of Fourleague Bay In Mississippi River Delta: Sediment Fluxes Across River-Estuary-Wetland Boundaries, Nan Wang, Qin Chen, Kelin Hu, Kehui Xu, Samuel J. Bentley, Jiaze Wang Dec 2023

Morphodynamic Modeling Of Fourleague Bay In Mississippi River Delta: Sediment Fluxes Across River-Estuary-Wetland Boundaries, Nan Wang, Qin Chen, Kelin Hu, Kehui Xu, Samuel J. Bentley, Jiaze Wang

Faculty Publications

To mitigate land losses in the Mississippi River Delta, sediment diversions are being employed to enable the flow of river water and sediments into wetlands experiencing degradation. A two-dimensional coupled flow-wave Delft3D model was used in this study to explore the hydrodynamics and sediment transport in Fourleague Bay (FLB), Louisiana, USA, which has been considered an analog site for studying the efficiency of sediment diversion projects. In-situ measurements of sediment accretion and hydrodynamic characteristics from 2015 to 2016 were utilized to calibrate and validate the morphodynamic model. The validated model was then applied to quantify sediment transport in FLB and …

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Sediment Delivery To Sustain The Ganges-Brahmaputra Delta Under Climate Change And Anthropogenic Impacts, Jessica L. Raff, Steven L. Goodbred, Jennifer L. Pickering, Ryan S. Sincavage, John C. Ayers, Md Saddam Hossain, Carol A. Wilson, Chris Paola, Michael S. Steckler, Dhiman R. Mondal, Jean Louis Grimaud, Celine Jo Grall, Kimberly G. Rogers, Kazi Matin Ahmed, Syed Humayun Akhter, Brandee N. Carlson, Elizabeth L. Chamberlain, Meagan Dejter, Jonathan M. Gilligan, Richard P. Hale, Mahfuzur R. Khan, Md Golam Muktadir, Md Munsur Rahman, Lauren A. Williams Dec 2023

Sediment Delivery To Sustain The Ganges-Brahmaputra Delta Under Climate Change And Anthropogenic Impacts, Jessica L. Raff, Steven L. Goodbred, Jennifer L. Pickering, Ryan S. Sincavage, John C. Ayers, Md Saddam Hossain, Carol A. Wilson, Chris Paola, Michael S. Steckler, Dhiman R. Mondal, Jean Louis Grimaud, Celine Jo Grall, Kimberly G. Rogers, Kazi Matin Ahmed, Syed Humayun Akhter, Brandee N. Carlson, Elizabeth L. Chamberlain, Meagan Dejter, Jonathan M. Gilligan, Richard P. Hale, Mahfuzur R. Khan, Md Golam Muktadir, Md Munsur Rahman, Lauren A. Williams

Faculty Publications

The principal nature-based solution for offsetting relative sea-level rise in the Ganges-Brahmaputra delta is the unabated delivery, dispersal, and deposition of the rivers’ ~1 billion-tonne annual sediment load. Recent hydrological transport modeling suggests that strengthening monsoon precipitation in the 21st century could increase this sediment delivery 34-60%; yet other studies demonstrate that sediment could decline 15-80% if planned dams and river diversions are fully implemented. We validate these modeled ranges by developing a comprehensive field-based sediment budget that quantifies the supply of Ganges-Brahmaputra river sediment under varying Holocene climate conditions. Our data reveal natural responses in sediment supply comparable to …

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Hybrid Hemp/Glass Fiber Reinforced High-Temperature Shape Memory Photopolymer With Mechanical And Flame-Retardant Analysis, Sakil Mahmud, John Konlan, Jenny Deicaza, Guoqiang Li Dec 2023

Hybrid Hemp/Glass Fiber Reinforced High-Temperature Shape Memory Photopolymer With Mechanical And Flame-Retardant Analysis, Sakil Mahmud, John Konlan, Jenny Deicaza, Guoqiang Li

Faculty Publications

Cultivated natural fibers have a huge possibility for green and sustainable reinforcement for polymers, but their limited load-bearing ability and flammability prevent them from wide applications in composites. According to the beam theory, normal stress is the maximum at the outermost layers but zero at the mid-plane under bending (with (non)linear strain distribution). Shear stress is the maximum at the mid-plane but manageable for most polymers. Accordingly, a laminated composite made of hybrid fiber-reinforced shape memory photopolymer was developed, incorporating strong synthetic glass fibers over a weak core of natural hemp fibers. Even with a significant proportion of natural hemp …

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