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Evaluation Of Organic And Synthetic Herbicide Applications On Weed Suppression In A Conventional Cropping System In Louisiana, Caitlin Denux, Aixin Hou, Lisa Fultz Apr 2024

Evaluation Of Organic And Synthetic Herbicide Applications On Weed Suppression In A Conventional Cropping System In Louisiana, Caitlin Denux, Aixin Hou, Lisa Fultz

Faculty Publications

Synthetic herbicides, with their varying modes of action, are well known for their efficiency in the suppression and control of weed species in U.S. agriculture. However, the consequences of using synthetic herbicides without attention to the surrounding environment produce chemical run-off, changes in soil health and soil health conditions, and create herbicide-resistant weeds. These outcomes have encouraged growers to seek alternative methods for their weed management programs or farming operations. Organic production systems and organic pesticides have helped address these challenges related to sustainability and environmental health. However, the use of organic herbicides in a conventional cropping system is not …


Stimulation Of Small Phytoplankton Drives Enhanced Sinking Particle Formation In A Subtropical Ocean Eddy, Haoran Liu, Thomas J. Browning, Edward A. Laws, Yibin Huang, Lei Wang, Yiwei Shang, Xiaogang Xing, Kuanbo Zhou, Zong Pei Jiang, Xin Liu, Bangqin Huang, Minhan Dai Apr 2024

Stimulation Of Small Phytoplankton Drives Enhanced Sinking Particle Formation In A Subtropical Ocean Eddy, Haoran Liu, Thomas J. Browning, Edward A. Laws, Yibin Huang, Lei Wang, Yiwei Shang, Xiaogang Xing, Kuanbo Zhou, Zong Pei Jiang, Xin Liu, Bangqin Huang, Minhan Dai

Faculty Publications

Nutrient transfer into the sunlit surface ocean by cyclonic eddies is potentially crucial for sustaining primary productivity in the stratified subtropical gyres. However, the nature of productivity enhancements, including the flow of matter to higher trophic levels and its impact on carbon fluxes, remain poorly resolved. Here, we report a detailed assessment of the biogeochemical response to a cyclonic eddy in the subtropical Northwest Pacific via a combination of ship-based and autonomous platforms. Primary production was enhanced twofold within the eddy core relative to reference sites outside, whereas phytoplankton biomass even decreased. Pico-phytoplankton (< 2 μm) dominated (> 80%) both phytoplankton biomass and primary …


New Genera And Species Of Caulobacter And Brevundimonas Bacteriophages Provide Insights Into Phage Genome Evolution, Bert Ely, Michael Hils, Aaron Clarke, Maegan Albert, Nadia Holness, Jacob Lenski, Tannaz Mohammadi Apr 2024

New Genera And Species Of Caulobacter And Brevundimonas Bacteriophages Provide Insights Into Phage Genome Evolution, Bert Ely, Michael Hils, Aaron Clarke, Maegan Albert, Nadia Holness, Jacob Lenski, Tannaz Mohammadi

Faculty Publications

Previous studies have identified diverse bacteriophages that infect Caulobacter vibrioides strain CB15 ranging from small RNA phages to four genera of jumbo phages. In this study, we focus on 20 bacteriophages whose genomes range from 40 to 60 kb in length. Genome comparisons indicated that these diverse phages represent six Caulobacter phage genera and one additional genus that includes both Caulobacter and Brevundimonas phages. Within species, comparisons revealed that both single base changes and inserted or deleted genetic material cause the genomes of closely related phages to diverge. Among genera, the basic gene order and the orientation of key genes …


How To Deal With Theological Conflicts, Part 2, Timothy Blaze, S. Joseph Kidder Apr 2024

How To Deal With Theological Conflicts, Part 2, Timothy Blaze, S. Joseph Kidder

Faculty Publications

No abstract provided.


Revisiting The Federal Circuit En Banc, Ryan Vacca Apr 2024

Revisiting The Federal Circuit En Banc, Ryan Vacca

Faculty Publications

The United States Court of Appeals for the Federal Circuit ("Federal Circuit") holds exclusive jurisdiction over patent appeals and plays a vital role in shaping patent law and policy in the United States. Since its inception in 1982, the Federal Circuit has used en bane review as a crucial method to develop patent law and policy. Until recently, the court had been a model for en bane review by frequently hearing patent cases en bane, addressing important questions for a wide range of stakeholders in the patent system, and freely inviting amici to participate in the en bane process. Through …


The Brady Database, Brandon L. Garrett, Adam M. Gershowitz, Jennifer Teitcher Apr 2024

The Brady Database, Brandon L. Garrett, Adam M. Gershowitz, Jennifer Teitcher

Faculty Publications

The Supreme Court’s landmark ruling in Brady v. Maryland turns sixty this year. The Brady doctrine, which requires the government to disclose favorable and material evidence to the defendant, is one of the most frequently litigated criminal procedure issues. Yet, despite decades of Brady cases in federal and state courts, we still know relatively little about how Brady claims are litigated, adjudicated, and what such claims can tell us about the criminal justice system writ large. Scholars are in the dark about how often Brady violations occur, whether it is primarily the fault of prosecutors or the police, whether violations …


A Threshold Assessment: Is Technology Among The Competencies Tested By The Mpre?, Amy A. Emerson Apr 2024

A Threshold Assessment: Is Technology Among The Competencies Tested By The Mpre?, Amy A. Emerson

Faculty Publications

No abstract provided.


Pulsed-Power Neutron Production With Deuterated Polymer Accelerator Targets, Anthony O. Hagey, Juan J. Manfredi, Whitman T. Dailey, S. L. Jackson, E. R. Kaiser, J, W. Schumer Apr 2024

Pulsed-Power Neutron Production With Deuterated Polymer Accelerator Targets, Anthony O. Hagey, Juan J. Manfredi, Whitman T. Dailey, S. L. Jackson, E. R. Kaiser, J, W. Schumer

Faculty Publications

This document presents an investigation of the effect of deuterated accelerator targets on the neutron fluence from a local mass injection dense plasma focus (LMIDPF) driven by the United States Naval Research Laboratory's (NRL) Hawk pulsed-power generator. Deuterated targets were made using two methods: a well-established thin-film casting technique for flat targets and a more novel additive manufacturing technique that allowed targets to be three-dimensional (3D) printed in both flat and conical geometries. These targets were then tested during neutron-producing experiments conducted using Hawk, and theneutron fluences measured for the various target types were compared. Additive manufacturing was used as …


Role Of Electronegativity In Environmentally Persistent Free Radicals (Epfrs) Formation On Zno, Syed Monjur Ahmed, Reuben A. Oumnov, Orhan Kizilkaya, Randall W. Hall, Phillip T. Sprunger, Robert L. Cook Mar 2024

Role Of Electronegativity In Environmentally Persistent Free Radicals (Epfrs) Formation On Zno, Syed Monjur Ahmed, Reuben A. Oumnov, Orhan Kizilkaya, Randall W. Hall, Phillip T. Sprunger, Robert L. Cook

Faculty Publications

Environmentally persistent free radicals (EPFRs), a group of emerging pollutants, have significantly longer lifetimes than typical free radicals. EPFRs form by the adsorption of organic precursors on a transition metal oxide (TMO) surface involving electron charge transfer between the organic and TMO. In this paper, dihalogenated benzenes were incorporated to study the role of electronegativity in the electron transfer process to obtain a fundamental knowledge of EPFR formation mechanism on ZnO. Upon chemisorption on ZnO nanoparticles at 250 °C, electron paramagnetic resonance (EPR) confirms the formation of oxygen adjacent carbon-centered organic free radicals with concentrations between 1016 and 10 …


17O-Excess In Tropical Cyclones Reflects Local Rain Re-Evaporation More Than Moisture Source Conditions, Chijun Sun, Timothy Shanahan, Shaoneng He, Adriana Bailey, Jesse Nusbaumer, Jun Hu, Aubrey Hillman, Erika Ornouski, Jacob Warner, Kristine Delong Mar 2024

17O-Excess In Tropical Cyclones Reflects Local Rain Re-Evaporation More Than Moisture Source Conditions, Chijun Sun, Timothy Shanahan, Shaoneng He, Adriana Bailey, Jesse Nusbaumer, Jun Hu, Aubrey Hillman, Erika Ornouski, Jacob Warner, Kristine Delong

Faculty Publications

17O-excess is a relatively new water isotope parameter that could potentially provide useful information about the hydrological cycle. Previous works focusing on 17O-excess in polar regions suggest that it primarily tracks moisture source relative humidity, but little is known about how to interpret 17O-excess data in lower latitudes. Here we present quasi-hourly triple oxygen isotope data of precipitation collected from two tropical cyclones in Texas and Louisiana in 2020 to understand the impacts of environmental and meteorological processes on the 17O-excess of low-to mid-latitude precipitation. We find that at both hourly timescales and the event scale, 17O-excess is strongly correlated …


Effect Of Fabrication Parameters On The Ferroelectricity Of Hafnium Zirconium Oxide Films: A Statistical Study, Guillermo A. Salcedo, Ahmad E. Islam, Elizabeth Reichley, Michael Dietz, Christine M. Schubert Kabban, Kevin D. Leedy, Tyson C. Back, Weison Wang, Andrew Green, Timothy S. Wolfe, James M. Sattler Mar 2024

Effect Of Fabrication Parameters On The Ferroelectricity Of Hafnium Zirconium Oxide Films: A Statistical Study, Guillermo A. Salcedo, Ahmad E. Islam, Elizabeth Reichley, Michael Dietz, Christine M. Schubert Kabban, Kevin D. Leedy, Tyson C. Back, Weison Wang, Andrew Green, Timothy S. Wolfe, James M. Sattler

Faculty Publications

Ferroelectricity in hafnium zirconium oxide (Hf1−xZrxO2) and the factors that impact it have been a popular research topic since its discovery in 2011. Although the general trends are known, the interactions between fabrication parameters and their effect on the ferroelectricity of Hf1−xZrxO2 require further investigation. In this paper, we present a statistical study and a model that relates Zr concentration (x), film thickness (tf), and annealing temperature (Ta) with the remanent polarization (Pr) in tungsten (W)-capped Hf1−xZrxO2. …


Dissociating Reading And Auditory Comprehension In Persons With Aphasia, Rachel M. Harrington, Sigfus Kristinsson, Janina Wilmskoetter, Natalie Busby, Dirk Den Ouden, Chris Rorden, Julius Fridriksson Ph.D., Leonardo Bonilha Mar 2024

Dissociating Reading And Auditory Comprehension In Persons With Aphasia, Rachel M. Harrington, Sigfus Kristinsson, Janina Wilmskoetter, Natalie Busby, Dirk Den Ouden, Chris Rorden, Julius Fridriksson Ph.D., Leonardo Bonilha

Faculty Publications

Language comprehension is often affected in individuals with post-stroke aphasia. However, deficits in auditory comprehension are not fully correlated with deficits in reading comprehension and the mechanisms underlying this dissociation remain unclear. This distinction is important for understanding language mechanisms, predicting long-term impairments and future development of treatment interventions. Using comprehensive auditory and reading measures from a large cohort of individuals with aphasia, we evaluated the relationship between aphasia type and reading comprehension impairments, the relationship between auditory versus reading comprehension deficits and the crucial neuroanatomy supporting the dissociation between post-stroke reading and auditory deficits. Scores from the Western Aphasia …


Selective Vapor Condensation For The Synthesis And Assembly Of Spherical Colloids With A Precise Rough Patch, Kennedy A. Guillot, Philip J. Brahana, Ahmed Al Harraq, Nduka D. Ogbonna, Nicholas S. Lombardo, Jimmy Lawrence, Yaxin An, Michael G. Benton, Bhuvnesh Bharti Mar 2024

Selective Vapor Condensation For The Synthesis And Assembly Of Spherical Colloids With A Precise Rough Patch, Kennedy A. Guillot, Philip J. Brahana, Ahmed Al Harraq, Nduka D. Ogbonna, Nicholas S. Lombardo, Jimmy Lawrence, Yaxin An, Michael G. Benton, Bhuvnesh Bharti

Faculty Publications

Patchy particles occupy an increasingly important space in soft matter research due to their ability to assemble into intricate phases and states. Being able to fine-tune the interactions among these particles is essential to understanding the principles governing the self-assembly processes. However, current fabrication techniques often yield patches that deviate chemically and physically from the native particles, impeding the identification of the driving forces behind self-assembly. To overcome this challenge, we propose a new approach to synthesizing spherical colloids with a well-defined rough patch on their surface. By treating polystyrene microspheres with vapors of a good solvent, here an acetone-water …


Developmental Differences In Reported Speech And Internal State Language In Preschoolers’ Personal Narratives, Megan E. Welliver, Alice J. Davidson, Alexandra Mccrary Mar 2024

Developmental Differences In Reported Speech And Internal State Language In Preschoolers’ Personal Narratives, Megan E. Welliver, Alice J. Davidson, Alexandra Mccrary

Faculty Publications

The present study explored developmental differences in preschoolers’ use of reported speech and internal state language in personal narratives. Three-, four-, and five-year-olds attending a laboratory preschool shared 204 stories about ‘a time when you were happy/sad’. Stories were audio-recorded, transcribed, and coded for reported speech (direct, indirect, narrativized) and internal state language (cognitive states, total emotion terms, unique emotion terms). Personal narratives told by five-year-olds included more cognitive states and more narrativized speech than those told by three- and four-year-olds, even when accounting for children’s vocabulary skills, and that reported speech (narrativized, direct) were positively correlated with cognitive state …


The Gyrokinetic Dispersion Relation Of Microtearing Modes In Collisionless Toroidal Plasmas, Benjamin D G Chandran, A A. Schekochihin Mar 2024

The Gyrokinetic Dispersion Relation Of Microtearing Modes In Collisionless Toroidal Plasmas, Benjamin D G Chandran, A A. Schekochihin

Faculty Publications

We solve the linearized gyrokinetic equation, quasineutrality condition and Ampere's law to obtain the dispersion relation of microtearing modes (MTMs) in collisionless low- $\beta$ toroidal plasmas. Consistent with past studies, we find that MTMs are driven unstable by the electron temperature gradient and that this instability drive is mediated by magnetic drifts. The dispersion relation that we derive can be evaluated numerically very quickly and may prove useful for devising strategies to mitigate MTM instability in fusion devices.


The Gyrokinetic Dispersion Relation Of Microtearing Modes In Collisionless Toroidal Plasmas, Benjamin D G Chandran, A A. Schekochihin Mar 2024

The Gyrokinetic Dispersion Relation Of Microtearing Modes In Collisionless Toroidal Plasmas, Benjamin D G Chandran, A A. Schekochihin

Faculty Publications

We solve the linearized gyrokinetic equation, quasineutrality condition and Ampere's law to obtain the dispersion relation of microtearing modes (MTMs) in collisionless low- $\beta$ toroidal plasmas. Consistent with past studies, we find that MTMs are driven unstable by the electron temperature gradient and that this instability drive is mediated by magnetic drifts. The dispersion relation that we derive can be evaluated numerically very quickly and may prove useful for devising strategies to mitigate MTM instability in fusion devices.


Doubly Charged Dimers And Trimers Of Heavy Noble Gases, Gabriel Schöpfer, Stefan Bergmeister, Milan Ončák, Ianessa Stromberg, Masoomeh Mahmoodi-Darian, Paul Scheier, Olof Echt, Elisabeth Gruber Mar 2024

Doubly Charged Dimers And Trimers Of Heavy Noble Gases, Gabriel Schöpfer, Stefan Bergmeister, Milan Ončák, Ianessa Stromberg, Masoomeh Mahmoodi-Darian, Paul Scheier, Olof Echt, Elisabeth Gruber

Faculty Publications

Many doubly charged heteronuclear dimers are metastable or even thermodynamically stable with respect to charge separation. Homonuclear dicationic dimers, however, are more difficult to form. He22+ was the first noble gas dimer predicted to be metastable and, decades later, observed. Ne22+ is the only other dicationic noble gas dimer that has been detected so far. Here, we present a novel approach to form fragile dicationic species, by post-ionization of singly charged ions that are embedded in helium nanodroplets (HNDs). Bare ions are then extracted by colliding the HNDs with helium gas. We detect homonuclear doubly charged …


Examining The Utility Of The Early Childhood Development Index (Ecdi) Among Children In The Nigeria Context, Ngozi V. Enelamah, Smitha Rao, Margaret Lombe, Mansoo Yu, Chrisann Newransky, Chrisann Newransky, Melissa L. Villodas, Andrew Foell, Von Nebbitt Mar 2024

Examining The Utility Of The Early Childhood Development Index (Ecdi) Among Children In The Nigeria Context, Ngozi V. Enelamah, Smitha Rao, Margaret Lombe, Mansoo Yu, Chrisann Newransky, Chrisann Newransky, Melissa L. Villodas, Andrew Foell, Von Nebbitt

Faculty Publications

An estimated 6 million children under the age of five in Nigeria (out of nearly 31 million) risk not reaching their full developmental potential. The dearth of context-relevant measures poses a challenge to the planning and implementation of effective interventions. This study assesses the utility of the Early Childhood Development Index (ECDI) in Nigeria. We used the Multiple Indicator Cluster Surveys to track progress among 3- to 4-year-old children (n = 11,073); 3-year-old, 51%; female, 49%. Using random calibration samples, the results from psychometric tests indicate that while over half of the children were on track in their development based …


Coping With California’S Deficit, Part 1: Borrowing And Taxes, David Gamage, Darien Shanske Mar 2024

Coping With California’S Deficit, Part 1: Borrowing And Taxes, David Gamage, Darien Shanske

Faculty Publications

In this installment of Academic Perspectives on SALT, Shanske and Gamage examine California’s projected budget deficit and possible solutions. California has a large budget deficit that is predicted to last for several years. In this two-part series, we will place California’s situation in context and propose solutions.

The state should use short-term borrowing to cover at least some of the cyclical shortfall. That the real revenue cycle is unlikely to neatly unfold over one traditional fiscal year should not change this conclusion. To that end, we will show how California can operationalize this simple insight despite the impression some may …


Multi-Decadal Coastal Acidification In The Northern Gulf Of Mexico Driven By Climate Change And Eutrophication, Zong Pei Jiang, Cao Qin, Yiwen Pan, Chengfeng Le, Nancy Rabalais, Robert Eugene Turner, Katja Fennel, Kui Wang, Wei Jun Cai Mar 2024

Multi-Decadal Coastal Acidification In The Northern Gulf Of Mexico Driven By Climate Change And Eutrophication, Zong Pei Jiang, Cao Qin, Yiwen Pan, Chengfeng Le, Nancy Rabalais, Robert Eugene Turner, Katja Fennel, Kui Wang, Wei Jun Cai

Faculty Publications

Coastal waters often experience enhanced ocean acidification due to the combined effects of climate change and regional biological and anthropogenic activities. Through reconstructing summertime bottom pH in the northern Gulf of Mexico from 1986 to 2019, we demonstrated that eutrophication-fueled respiration dominated bottom pH changes on intra-seasonal and interannual timescales, resulting in recurring acidification coinciding with hypoxia. However, the multi-decadal acidification trend was principally driven by rising atmospheric CO2 and ocean warming, with more acidified and less buffered hypoxic waters exhibiting a higher rate of pH decline (− 0.0023 yr− 1) compared to non-hypoxic waters (− 0.0014 yr …


Teaching Statistics: A Technology-Enhanced Supportive Instruction (Tsi) Model During The Covid-19 Pandemic And Beyond, Serina Al-Haddad, Nancy Chick, Farshid Safi Mar 2024

Teaching Statistics: A Technology-Enhanced Supportive Instruction (Tsi) Model During The Covid-19 Pandemic And Beyond, Serina Al-Haddad, Nancy Chick, Farshid Safi

Faculty Publications

Many approaches exist in teaching statistics, however, learning statistics is frequently perceived by students as challenging. While evidence-based teaching approaches like case discussions and flipped-classroom models have been successfully incorporated into multiple disciplines, these methods can have inadequate success when students are affectively detached or sometimes paralyzed by the subject. The sudden need to switch to virtual teaching in Spring 2020 created unprecedented challenges that were overwhelming for instructors and students. This article explores the challenges of teaching a statistics course, and the importance of purposeful use of technology and supportive feedback to effectively engage students and promote learning. Furthermore, …


Hydroxymethanesulfonate And Sulfur(Iv) In Fairbanks Winter During The Alpaca Study, Kayane Dingilian, Elliana Hebert, Michael Battaglia Jr., James R. Campbell, Meeta Cesler-Maloney, William Simpson, Jason M. St. Clair, Jack E. Dibb, Brice Temime-Roussel, Barbara D’Anna Mar 2024

Hydroxymethanesulfonate And Sulfur(Iv) In Fairbanks Winter During The Alpaca Study, Kayane Dingilian, Elliana Hebert, Michael Battaglia Jr., James R. Campbell, Meeta Cesler-Maloney, William Simpson, Jason M. St. Clair, Jack E. Dibb, Brice Temime-Roussel, Barbara D’Anna

Faculty Publications

Hydroxymethanesulfonate (HMS) in fine aerosol particles has been reported at significant concentrations along with sulfate under extreme cold conditions (-35 °C) in Fairbanks, Alaska, a high latitude city. HMS, a component of S(IV) and an adduct of formaldehyde and sulfur dioxide, forms in liquid water. Previous studies may have overestimated HMS concentrations by grouping it with other S(IV) species. In this work, we further investigate HMS and the speciation of S(IV) through the Alaskan Layered Pollution and Chemical Analysis (ALPACA) intensive study in Fairbanks. We developed a method utilizing hydrogen peroxide to isolate HMS and found that approximately 50% of …


Reconsidering The Reliability Of Chemical Process Simulators I: Implementation Of The Murphree And Vaporization Efficiencies, Zachary Braswell, Brian F. Hanley, Holt Ragsdale Mar 2024

Reconsidering The Reliability Of Chemical Process Simulators I: Implementation Of The Murphree And Vaporization Efficiencies, Zachary Braswell, Brian F. Hanley, Holt Ragsdale

Faculty Publications

Most chemical process simulators in widespread use today allow users to apply some type of efficiency correction to individual equilibrium stages or to equilibrium stage sections in order to align the stage or section separation performance more closely to actual tray performance in the field. Some simulators even allow for the use of component efficiencies on individual stages or in stage sections. It is our contention, however, that two of the more commonly available efficiency models, the vaporization efficiency and Murphree vapor phase efficiency, have generally been implemented incorrectly. The three major conceptual inconsistencies are (1) the assumption that the …


Pal-Bert: An Improved Question Answering Model, Wenfeng Zheng, Siyu Lu, Zhuohang Cai, Ruiyang Wang, Lei Wang, Lirong Yin Mar 2024

Pal-Bert: An Improved Question Answering Model, Wenfeng Zheng, Siyu Lu, Zhuohang Cai, Ruiyang Wang, Lei Wang, Lirong Yin

Faculty Publications

In the field of natural language processing (NLP), there have been various pre-training language models in recent years, with question answering systems gaining significant attention. However, as algorithms, data, and computing power advance, the issue of increasingly larger models and a growing number of parameters has surfaced. Consequently, model training has become more costly and less efficient. To enhance the efficiency and accuracy of the training process while reducing the model volume, this paper proposes a first-order pruning model PAL-BERT based on the ALBERT model according to the characteristics of question-answering (QA) system and language model. Firstly, a first-order network …


Detecting Anomalies In Time Series Using Kernel Density Approaches, Robin Frehner, Kesheng Wu, Alexander Sim, Jinoh Kim Mar 2024

Detecting Anomalies In Time Series Using Kernel Density Approaches, Robin Frehner, Kesheng Wu, Alexander Sim, Jinoh Kim

Faculty Publications

This paper introduces a novel anomaly detection approach tailored for time series data with exclusive reliance on normal events during training. Our key innovation lies in the application of kernel-density estimation (KDE) to scrutinize reconstruction errors, providing an empirically derived probability distribution for normal events post-reconstruction. This non-parametric density estimation technique offers a nuanced understanding of anomaly detection, differentiating it from prevalent threshold-based mechanisms in existing methodologies. In post-training, events are encoded, decoded, and evaluated against the estimated density, providing a comprehensive notion of normality. In addition, we propose a data augmentation strategy involving variational autoencoder-generated events and a smoothing …


Computational Design Of An Electro-Organocatalyst For Conversion Of Co2 Into Formaldehyde, Foroogh Khezeli, Craig Plaisance Mar 2024

Computational Design Of An Electro-Organocatalyst For Conversion Of Co2 Into Formaldehyde, Foroogh Khezeli, Craig Plaisance

Faculty Publications

Density functional theory calculations employing a hybrid implicit/explicit solvation method were used to explore a new strategy for electrochemical conversion of CO2 using an electro-organocatalyst. A particular structural motif is identified that consists of an electron-rich vicinal enediamine (>N-C═C-N<) backbone, which is capable of activating CO2 by the formation of a C-C bond while subsequently facilitating the transfer of electrons from a chemically inert cathode to ultimately produce formaldehyde. Unlike transition metal-based electrocatalysts, the electro-organocatalyst is not constrained by scaling relations between the formation energies of activated CO2 and adsorbed CO, nor is it expected to be active for the competing hydrogen evolution reaction. The rate-limiting steps are found to occur during two proton-coupled electron transfer (PCET) sequences and are associated with the transfer of a proton from a proton transfer mediator to a carbon atom on the electro-organocatalyst. The difficulty of this step in the second PCET sequence necessitates an electrode potential of −0.85 V vs RHE to achieve the maximum turnover frequency. In addition, it is postulated that the electro-organocatalyst should also be capable of forming long-chain aldehydes by successively carrying out reductive aldol condensation to grow the alkyl chain one carbon at a time.


Enriched Regions Of 228Ra Along The U.S. Geotraces Pacific Meridional Transect (Gp15), Willard S. Moore, Matt Charette, Paul Henderson, Doug Hammond, Nathaniel Kemnitz, Emilie Leroy, Eun Young Kwon, Mikael Hult Mar 2024

Enriched Regions Of 228Ra Along The U.S. Geotraces Pacific Meridional Transect (Gp15), Willard S. Moore, Matt Charette, Paul Henderson, Doug Hammond, Nathaniel Kemnitz, Emilie Leroy, Eun Young Kwon, Mikael Hult

Faculty Publications

The half‐life of 228Ra (5.7 years) aligns well with near‐surface and near‐bottom ocean mixing timescales. Because 228Ra is sourced from sediments, regions of enhanced activity represent water that has recently interacted with sediments on the continental margin or seabed. The GP15 meridional transect from Alaska to Tahiti along152°W encountered several regions in the upper ocean where 228Ra was enriched. These enrichments follow surface and subsurface ocean current patterns and pair with earlier measurements of 228Ra and transient radionuclides to reveal the origins of these enriched regions. An enriched region at Alaska margin stations 1–3 was sourced locally but did not …


Laboratory Exercise For The Radiometry Student, Michael A. Marciniak Mar 2024

Laboratory Exercise For The Radiometry Student, Michael A. Marciniak

Faculty Publications

The U.S. Air and Space Forces require optical expertise among their personnel. The Air Force Institute of Technology offers a graduate optics curriculum, which includes a three-course sequence to educate students in the optical concepts of radiometry and radiometric instrumentation. We find radiometry is often a deceptively difficult concept for students to master. To address this, we have developed an experiment in our optics-laboratory coursework to help them gain this mastery. A Fourier-transform infrared spectrometer (FTS) is used to collect spectral data from an unknown sample. FTS calibration and data collection are discussed here, as are the two specific samples …


Relative Vectoring Using Dual Object Detection For Autonomous Aerial Refueling, Derek B. Worth, Jeffrey L. Choate, James Lynch, Scott L. Nykl, Clark N. Taylor Mar 2024

Relative Vectoring Using Dual Object Detection For Autonomous Aerial Refueling, Derek B. Worth, Jeffrey L. Choate, James Lynch, Scott L. Nykl, Clark N. Taylor

Faculty Publications

Once realized, autonomous aerial refueling will revolutionize unmanned aviation by removing current range and endurance limitations. Previous attempts at establishing vision-based solutions have come close but rely heavily on near perfect extrinsic camera calibrations that often change midflight. In this paper, we propose dual object detection, a technique that overcomes such requirement by transforming aerial refueling imagery directly into receiver aircraft reference frame probe-to-drogue vectors regardless of camera position and orientation. These vectors are precisely what autonomous agents need to successfully maneuver the tanker and receiver aircraft in synchronous flight during refueling operations. Our method follows a common 4-stage process …


Speculating About Genocide: The Queensland Frontier 1859–1897, Mark Finnane, Jonathan Richards Mar 2024

Speculating About Genocide: The Queensland Frontier 1859–1897, Mark Finnane, Jonathan Richards

Faculty Publications

In the colonisation of Queensland, Australia it is commonly accepted that large numbers of Indigenous people were killed in the second half of the nineteenth century. Calculations of violent mortality have recently been revised radically upwards. We suggest that the methodology deployed in these new studies is unreliable, reflecting errors in counting and calculation, as well as underestimating the selection bias of the samples. We caution against projecting aggregate violent mortality where the underlying data are so imperfect and emphasise the value of more detailed local and regional studies to inform better understanding of colonisation's impact on First Peoples.