Physical Sciences and Mathematics Commons^™

Dataset For: Multiple Local Σ-Aromaticity Of Nonagermanide Clusters, Alexander I. Boldyrev, Nikolay Tkachenko

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Nonagermanide clusters are widely used in inorganic synthesis and are actively studied by experimentalists and theoreticians. However, chemical bonding of such versatile species is still not completely understood. In our work we deciphered a bonding pattern for various experimentally obtained nonagermanide species. We localized the electron density via the AdNDP algorithm for the model structures ([Ge9]4−, [Ge9{P(NH2)2}3]−, Cu[Ge9{P(NH2)2}3] and Cu(NHC)[Ge9{P(NH2)2}3]) and obtained a simple and chemically intuitive bonding pattern which can explain the variety of active sites and the existence of both D3h and C4v geometries for such clusters. Moreover, the [Ge9]4− core is found to be a unique example …

Data From: Dibridged, Monobridged, Vinylidene-Like, And Linear Structures For The Alkaline Earth Dihydrides Be2h2, Mg2h2, Ca2h2, Sr2h2, And Ba2h2. Proposals For Observations, Alexander I. Boldyrev, Nikolay Tkachenko

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This research reports a search for peculiar monobridged structures of the E2H2 molecules (E = Be, Mg, Ca, Sr, Ba). For Be2H2 and Mg2H2, the monobridged geometry is not an equilibrium but rather a transition state between the vinylidene-like structure and the global minimum HE–EH linear geometry. However, for Ca2H2, Sr2H2, and Ba2H2, this situation changes significantly; the linear structure is no longer the global minimum but lies higher in energy than two other equilibria, the dibridged and monobridged structures. The planar dibridged structures of both Sr2H2 and Ba2H2 should be observable via IR spectroscopy. Although the remarkable monobridged structures …

Lessons From A Landscape Irrigation Rebate Program In Miami Dade County, Haimanote K. Bayabil, Laura Vasquez, Jesus Lomeli, Patrick Martin

The Journal of Extension

We calculated savings in outdoor water uses from 37 properties in Fisher Island, Florida, that were retrofitted with smart Evapotranspiration-based irrigation controllers through the Miami Dade County’s Landscape Irrigation Rebate Program. We found average water savings of 11.4 million gallons per year from the 37 properties on the island. We discuss the roles of extension personnel in developing and effectively managing an irrigation rebate program and the implications of results from this program for large scale efforts towards efficient use of freshwater resources.

Affectivetda: Using Topological Data Analysis To Improve Analysis And Explainability In Affective Computing, Hamza Elhamdadi

USF Tampa Graduate Theses and Dissertations

We present an approach utilizing Topological Data Analysis to study the structure of face poses used in affective computing, i.e., the process of recognizing human emotion. The approach uses conditional comparison of different emotions, both respective and irrespective of time, with multiple topological distance metrics, dimension reduction techniques, and face subsections (e.g., eyes, nose, mouth, etc.). The results confirm that our topology-based approach captures known patterns, distinctions between emotions, and distinctions between individuals, which is an important step towards more robust and explainable emotion recognition by machines.

Data For: Record Low Ionization Potentials Of Alkali Metal Complexes With Crown Ethers And Cryptands, Alexander I. Boldyrev, Nikolay Tkachenko

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Electronic properties of series of alkali metals complexes with crown ethers and cryptands were studied via DFT hybrid functionals. For [M([2.2.2]crypt)] (M=Li, Na, K) extremely low (1.70–1.52 eV) adiabatic ionization potentials were found. Such low values of ionization energies are significantly lower than those of alkali metal atoms. Thus, the investigated complexes can be defined as superalkalis. As a result, our investigation opens up new directions in the designing of chemical species with record low ionization potentials and extends the explanation of the ability of the cryptates and alkali crown ether complexes to stabilize multiple charged Zintl ions.

Effects Of Surface And Top Wind Shear On The Spatial Organization Of Marine Stratocumulus-Topped Boundary Layers, Monica Zamora Zapata, Thijs Heus, Jan Kleissl

Physics Faculty Publications

The convective nature of Stratocumulus topped boundary layers (STBL) involves the motion of updrafts and downdrafts, driven by surface fluxes and radiative cooling, respectively. The balance between shear and buoyant forcings at the surface can determine the organization of updrafts between cellular and roll structures. We investigate the effect of varying shear at the surface and top of the STBL using Large Eddy Simulations, taking DYCOMS II RF01 as a base case. We focus on spatial identification of the following features: coherent updrafts and downdrafts, and observe how they are affected by varying shear. Stronger surface shear organizes the updrafts …

Self-Contained Photon Coincidence Counting With Ni Myrio Ecosystem, Georges Oates Larsen, Andres H. La Rosa

University Honors Theses

Digital coincidence counting units (CCU) have made experimental verification of fundamental quantum mechanical principles financially accessible to undergraduate level teaching programs. However, recent implementations of these systems are not easily ported to National Instruments (NI) FPGAs, making them unsuitable for physics departments that have heavily invested in the NI ecosystem. Therefore, there is clear need for a detailed implementation based on an NI FPGA. We present a formal description of one such implementation, based on the NI myRIO (NI's lower-cost, student-oriented offering) which achieves 6.9 ns minimum guaranteed-distinguishable delay and 32.2 MHz peak coincidence counting rate with four input channels …

Case Study Of Scrum Methodology As Used By A Capstone Team, Lilly I. Yeaton

University Honors Theses

Scrum is widely used in the software industry to manage all kinds of projects. This case study examines the way in which a capstone team used the methodology and models the specific project management processes they used over the course of their project. These models and the process modifications therein are then compared to the team’s velocity at different points in the project. The results of this analysis suggest a correlation between asynchronous daily meetings and sprint reviews and improved velocity.

Radioisotope Constraints Of Arctic Deep Water Export To The North Atlantic, Lauren Kipp, Jerry F. Manus, Markus Kienast

School of Earth & Environment Departmental Research

The export of deep water from the Arctic to the Atlantic contributes to the formation of North Atlantic Deep Water, a crucial component of global ocean circulation. Records of protactinium-231 (231Pa) and thorium-230 (230Th) in Arctic sediments can provide a measure of this export, but well-constrained sedimentary budgets of these isotopes have been difficult to achieve in the Arctic Ocean. Previous studies revealed a deficit of 231Pa in central Arctic sediments, implying that some 231Pa is either transported to the margins, where it may be removed in areas of higher particle flux, or exported from the Arctic via deep water …

Data From: Computational Prediction Of The Low-Temperature Ferromagnetic Semiconducting 2d Sin Monolayer, Alexander I. Boldyrev, Nikolay Tkachenko

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Since the discovery of graphene, 2D materials have captured the minds of scientists because of their attractive and unique electronic properties. In particular, magnetic 2D materials have become a subject of extensive discussions today. Using density functional theory calculations, it is shown that 2D SiN sheet (built out of nonmetallic main group atoms) is a ferromagnetic semiconducting material with a magnetic moment 1 μB per unit cell and an indirect bandgap of 1.55 eV. Calculated phonon spectrum and conducted ab initio molecular dynamics simulation reveal thermal and dynamical stability of the designed material. It is shown that the ferromagnetic state …

Constraints On Cosmic Strings Using Data From The Third Advanced Ligo–Virgo Observing Run, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Karla E. Ramirez, W. H. Wang

Physics and Astronomy Faculty Publications and Presentations

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop …

Functional Role Of The N-Terminal Domain In Connexin 46/50 By In Silico Mutagenesis And Molecular Dynamics Simulation, Umair Khan

University Honors Theses

Connexins form intercellular channels known as gap junctions that facilitate diverse physiological roles, from long-range electrical and chemical coupling to nutrient exchange. Recent structural studies on Cx46 and Cx50 have defined a novel and stable open state and implicated the amino-terminal (NT) domain as a major contributor to functional differences between connexin isoforms. This thesis presents two studies which use molecular dynamics simulations with these new structures to provide mechanistic insight into the function and behavior of the NTH in Cx46 and Cx50. In the first, residues in the NTH that differ between Cx46 and Cx50 are swapped between the …

Do Secondary Cyclones Increase The Category Scale Of Atmospheric Rivers?, Edgar Sanchez Fausto

University Honors Theses

Atmospheric rivers (ARs) play a crucial role in delivering precipitation worldwide. This makes them an important phenomenon for water resource specialists to study. One such interest is to understand what mechanisms make ARs produce significant rainfall and associated hazards such as flooding. One possible mechanism is that AR duration or intensity may increase when it interacts with a secondary cyclone, either of which can increase the AR category scale. The purpose of this study is to determine whether AR and secondary cyclone interactions increase the category scale ARs. Out of 52 AR events analyzed, 32 events contained at least one …

A Study Of Stable Isotopes In Snow On Mt. Hood, Oregon, Maya Felix

University Honors Theses

Over the 2020-2021 Winter, event-based and end-of-season snow samples were collected on Mt. Hood near Government Camp, OR and analyzed for their stable isotopic compositions of ¹⁸O and ²H. It was found that surficial snow collected through the winter had higher variation in isotopic values than samples from a snow pit collected in spring. This suggests homogenization occurred in the snowpack over the season from snow metamorphism, sublimation, and/or melting. Homogenization of the snowpack will likely become more pronounced as temperatures increase and rain falls more often than snow due to climate change. Research that utilizes the snowpack …

Literature Review: Pollutant Removal Efficacy Of Floating Treatment Wetlands Across Water Bodies, Sophie Johnson

University Honors Theses

Wetland numbers are declining worldwide and there is a need to replace the water filtration services they provide. One emerging option is floating treatment wetlands (FTW). FTW are a floating mat that serves as a habitat for aquatic plants whose roots are suspended in the water and that remove both organic and inorganic pollutants like nutrients (nitrogen and phosphorus), potentially toxic metals, and suspended solids. A literature search was performed to examine the efficacy of FTW pollutant removal. Specifically, I inspected 1) how effective FTW are at removing a range of nutrients; 2) what types of plants are most effective …

Automated Decision Making And Machine Learning: Regulatory Alternatives For Autonomous Settings, Alyssa Heminger

University Honors Theses

Given growing investment capital in research and development, accompanied by extensive literature on the subject by researchers in nearly every domain from civil engineering to legal studies, automated decision-support systems (ADM) are likely to see a place in the foreseeable future. Artificial intelligence (AI), as an automated system, can be defined as a broad range of computerized tasks designed to replicate human neural networks, store and organize large quantities of information, detect patterns, and make predictions with increasing accuracy and reliability. By itself, artificial intelligence is not quite science-fiction tropes (i.e. an uncontrollable existential threat to humanity) yet not without …

St-V-Net: Incorporating Shape Prior Into Convolutional Neural Networks For Proximal Femur Segmentation, Chen Zhao, Joyce H. Keyak, Jinshan Tang, Tadashi S. Kaneko, Sundeep Khosla, Weihua Zhou, Et. Al.

Michigan Tech Publications

We aim to develop a deep-learning-based method for automatic proximal femur segmentation in quantitative computed tomography (QCT) images. We proposed a spatial transformation V-Net (ST-V-Net), which contains a V-Net and a spatial transform network (STN) to extract the proximal femur from QCT images. The STN incorporates a shape prior into the segmentation network as a constraint and guidance for model training, which improves model performance and accelerates model convergence. Meanwhile, a multi-stage training strategy is adopted to fine-tune the weights of the ST-V-Net. We performed experiments using a QCT dataset which included 397 QCT subjects. During the experiments for the …

Environmental, Health And Safety Intricacies Of Artisanal Mining In The Gold-Rich Landscapes Of Karamoja, North-Eastern Uganda, Eria Serwajja, Paul Isolo Mukwaya

Journal of Sustainable Mining

Artisanal small-scale gold mining presents opportunities for Uganda’s rural poor. However, it also poses serious environmental, health and safety challenges. A suite of data collection methods including interviews, focus groups discussions, water and soils sampling were used to examine the perceptions of miners on the status, prevalence and extent of mercury use in artisanal gold mining, mercury transit routes and toxicity levels of soils and water in Karamoja sub-region. It also explores the health, safety and environmental implications of artisanal small-scale gold mining in the sub-region. The findings show that trade and access to mercury is widespread; although trade in, …

Mathematical Modelling & Simulation Of Large And Small Scale Structures In Star Formation, Gianfranco Bino

Electronic Thesis and Dissertation Repository

This thesis aims to study the magnetic and evolutionary properties of stellar objects from the prestellar phase up to and including the late protostellar phase. Many of the properties governing star formation are linked to the core’s physical properties and the magnetic field highly dictates much of the core’s stability.

The thesis begins with the implementation of a fully analytic magnetic field model used to study the magnetic properties governing the prestellar core FeSt 1-457. The model is a direct result of Maxwell’s equations and yields a central-to-surface magnetic field ratio in the equatorial plane in cylindrical coordinates. The model …

Studies On Relationship Of Sex Ratio And Population Of Clawed Jird And Striped Hamster, Liqing Wang, Yuping Yang, Xiaodong Wu, Xixian Hou, Weihui Dong

IGC Proceedings (1993-2023)

No abstract provided.

Control Of Noxious Weed Cenchrus Biflorus—Effect Of Lablab As A Cover Crop, F. Peter Wandera, A. Abdullahi

IGC Proceedings (1993-2023)

No abstract provided.

Propargyl Radicals In Organic Synthesis, Marcus Muresan, Hariharaputhiran Subramanian, Mukund P. Sibi, James R. Green

Chemistry and Biochemistry Publications

The appearance of propargyl radicals as synthetic intermediates has increased in recent years from a structural curiosity to a frequent occurrence. This minireview covers the synthetically relevant organic chemistry involving the intermediacy of propargyl radicals. The review is organized by the process employed in radical generation, including H-atom abstraction, propargyl-X homolyses, radical addition to enynes, reduction of polar C=X bonds, reductions of stable carbocations, and metal-mediated coupling reactions. The relevant mechanisms of generation and reaction are discussed, as are applications in syntheses of target molecules of interest.

Uneven Increases In Racial Diversity Of Us Geoscience Undergraduates, Rachel J. Beane, Eric M.D. Baer, Rowan Lockwood, R. Heather Macdonald, John R. Mcdaris, Vernon R. Morris, I. Joshua Villalobos, Lisa D. White

Earth and Oceanographic Science Faculty Work

No abstract provided.

Latitudinal Variation In Monthly-Scale Reproductive Synchrony Among Acropora Coral Assemblages In The Indo-Pacific, Jessica Bouwmeester, Alasdair J. Edwards, James R. Guest, Andrew G. Bauman, Michael L. Berumen, Andrew H. Baird

Marine & Environmental Sciences Faculty Articles

Early research into coral reproductive biology suggested that spawning synchrony was driven by variations in the amplitude of environmental variables that are correlated with latitude, with synchrony predicted to break down at lower latitudes. More recent research has revealed that synchronous spawning, both within and among species, is a feature of all speciose coral assemblages, including equatorial reefs. Nonetheless, considerable variation in reproductive synchrony exists among locations and the hypothesis that the extent of spawning synchrony is correlated with latitude has not been formally tested on a large scale. Here, we use data from 90 sites throughout the Indo-Pacific and …

Early Dark Energy Is Not Excluded By Current Large-Scale Structure Data, Tristan L. Smith, V. Poulin, J. L. Bernal, K. K. Boddy, M. Kamionkowski, R. Murgia

Physics & Astronomy Faculty Works

We revisit the impact of early dark energy (EDE) on galaxy clustering using BOSS galaxy power spectra, analyzed using the effective field theory (EFT) of large-scale structure (LSS) and anisotropies of the cosmic microwave background (CMB) from Planck. Recent studies found that these data place stringent constraints on the maximum abundance of EDE allowed in the Universe. We argue here that their conclusions are a consequence of their choice of priors on the EDE parameter space, rather than any disagreement between the data and the model. For example, when considering EFT-LSS, CMB, and high-redshift supernovae data we find the …

Tests Of General Relativity With Binary Black Holes From The Second Ligo-Virgo Gravitational-Wave Transient Catalog, R. Abbott, T. D. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

Gravitational waves enable tests of general relativity in the highly dynamical and strong-field regime. Using events detected by LIGO-Virgo up to 1 October 2019, we evaluate the consistency of the data with predictions from the theory. We first establish that residuals from the best-fit waveform are consistent with detector noise, and that the low- and high-frequency parts of the signals are in agreement. We then consider parametrized modifications to the waveform by varying post-Newtonian and phenomenological coefficients, improving past constraints by factors of ∼2; we also find consistency with Kerr black holes when we specifically target signatures of the spin-induced …

Inducing Stereotypical Character Roles From Plot Structure, Labiba Jahan

FIU Electronic Theses and Dissertations

If we are to understand stories, we must understand characters: characters are central to every narrative and drive the action forward. Critically, many stories (especially cultural ones) employ stereotypical character roles in their stories for different purposes, including efficient communication among bundles of default characteristics and associations, ease understanding of those characters' role in the overall narrative, and many more. These roles include ideas such as hero, villain, or victim, as well as culturally-specific roles such as, for example, the donor (in Russian tales) or the trickster (in Native American tales). My thesis aims to learn these roles automatically, inducing …

Data-Driven Artificial Intelligence For Calibration Of Hyperspectral Big Data, Vasit Sagan, Maitiniyazi Maimaitijiang, Sidike Paheding, Sourav Bhadra, Nichole Gosselin, Max Burnette, Jeffrey Demieville, Sean Hartling, David Lebauer, Maria Newcomb, Duke Pauli, Kyle T. Peterson, Nadia Shakoor, Abby Stylianou, Charles S. Zender, Todd C. Mockler

Michigan Tech Publications

Near-earth hyperspectral big data present both huge opportunities and challenges for spurring developments in agriculture and high-throughput plant phenotyping and breeding. In this article, we present data-driven approaches to address the calibration challenges for utilizing near-earth hyperspectral data for agriculture. A data-driven, fully automated calibration workflow that includes a suite of robust algorithms for radiometric calibration, bidirectional reflectance distribution function (BRDF) correction and reflectance normalization, soil and shadow masking, and image quality assessments was developed. An empirical method that utilizes predetermined models between camera photon counts (digital numbers) and downwelling irradiance measurements for each spectral band was established to perform …

Protein Motifs For Proton Transfers That Build The Transmembrane Proton Gradient, Divya Kaur, Umesh Khaniya, Yingying Zhang, M. R. Gunner

Publications and Research

Biological membranes are barriers to polar molecules, so membrane embedded proteins control the transfers between cellular compartments. Protein controlled transport moves substrates and activates cellular signaling cascades. In addition, the electrochemical gradient across mitochondrial, bacterial and chloroplast membranes, is a key source of stored cellular energy. This is generated by electron, proton and ion transfers through proteins. The gradient is used to fuel ATP synthesis and to drive active transport. Here the mechanisms by which protons move into the buried active sites of Photosystem II (PSII), bacterial RCs (bRCs) and through the proton pumps, Bacteriorhodopsin (bR), Complex I and Cytochrome …

On-Chip Nanoscale Plasmonic Optical Modulators, Abdalrahman Mohamed Nader Abdelhamid

Theses and Dissertations

In this thesis work, techniques for downsizing Optical modulators to nanoscale for the purpose of utilization in on chip communication and sensing applications are explored. Nanoscale optical interconnects can solve the electronics speed limiting transmission lines, in addition to decrease the electronic chips heat dissipation. A major obstacle in the path of achieving this goal is to build optical modulators, which transforms data from the electrical form to the optical form, in a size comparable to the size of the electronics components, while also having low insertion loss, high extinction ratio and bandwidth. Also, lap-on-chip applications used for fast diagnostics, …