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Recent Submissions
Design and Synthesis of 8-Trifluoromethyl-Substituted Heterocyclic Small Molecule Mitochondrial Uncouplers for the Treatment of Metabolic Diseases
Krinos, Emily (Virginia Tech, 2026-02-27)
Developing C–H bond Functionalization, Organocatalytic Hydrophosphination Reactions and Anti-Invasion Agents
Gwinn, Reilly (Virginia Tech, 2026-02-27)
In chapters 1-3, we will discuss the development of iron alkoxide complexes for C–H bond functionalization. Currently, methods for C–H bond functionalization rely on precious metal catalysts that present environmental and health concerns. Earth abundant metals have been explored as sustainable catalysts; however, these systems are difficult to develop because of their distinct chemical properties and reactivity patterns compared to 4d and 5d metals. Several reported monometallic iron imido MLMB species capable of nitrene group transfer do so by accessing high-spin states, although their instability limits their applications. Bimetallic species were proposed to improve stability, but these complexes are difficult to synthesize and appeared to be unreactive. Herein, we disclose the Lewis base enhanced C–H bond functionalization mediated by a diiron alkoxide species. Alkoxide ligands were employed to synthesize high-spin bimetallic species due to their weak field and π-donor character, and substituted pyridines were utilized as a handle for nuclearity and reactivity control. Sterically encumbered pyridines allowed access to asymmetric bimetallic complexes (2.5a and 2.6a) and electron rich pyridines resulted in the monometallic analogs (2.2a-2.4a). Electron withdrawing p-trifluoromethylpyridine selectively accessed both the asymmetric dinuclear and mononuclear species indicative of electronic and steric controls. Diiron imido species were isolated with and without pyridine via nitrene capture with aryl azides (3.2a, 3.2b, 3.6a, and 3.6b) and demonstrated Lewis based enhanced toluene amination through a bimetallic pathway.
In chapter 5, we will discuss the phosphine-catalyzed regio- and stereoselective hydrophosphination of 1,3-diynes. Diynes are important scaffolds for synthesizing π-conjugated organic frameworks for applications in organic synthesis and materials. The selective functionalization of diynes allows researchers to control the chemical properties of highly conjugated compounds for applications in optic and data storage devices. Phosphines have been shown to enhance the photochemical properties of unsaturated frameworks because of their unique metal-like properties; however, the hydrophosphination of 1,3-diynes is scarcely reported and requires the use of precious metals, alkali metals, or prefunctionalized materials. In this dissertation, we describe a facile method to access previously unreported (E)-(1,4-diphenylbut-1-en-3-yn-2-yl)diphenylphosphanes via the organocatalytic hydrophosphination of 1,4-diphenylbuta-1,3-diynes. The reaction employs catalytic n-tributylphosphine, has a mild substrate scope, and proceeds in a regio- and stereoselective fashion.
In chapter 4, we will discuss the development of small molecule anti-invasion agents for the treatment of metastatic cancer. Metastasis remains the leading cause of anti-cancer treatment therapy and cancer-related death. The rapid spread and mutation of the cancerous cells complicates treatment and increases the chance of recurrence. Treatment options are limited because most anti-cancer agents inhibit tumor growth or cause apoptosis, but do not inhibit cancer spread, which is imperative for treating metastatic cancer. Recently, small molecule PDZ1i displayed anti-invasion activity and showed improved survival in multiple in vivo metastatic cancer mouse models. Inspired by PDZ1i, we conducted a structure activity relationship study of related small molecules with the aim of improving anti-invasion activity. Herein, we report a focused library of substituted 1-(benzo[d]thiazol-2-yl)-3-phenylurea derivatives inspired by the anti-invasion and anti-metastatic agent, PDZ1i. Our studies revealed that 1-(benzo[d]thiazol-2-yl)-3-phenylurea derivatives bearing 6-trifluoromethyl (4.3y) and 6-bromo (4.3aa) substituents display anti-invasion activity comparable to PDZ1i. The reported 1-(benzo[d]thiazol-2-yl)-3-phenylurea derivatives serve as promising starting points for future investigations of small molecule anti-invasion agents with potential to prevent and treat metastatic cancers.
From PFAS source attribution to collaborative management in a One Water system
Krauss, Lauren; Rashid, Md Redowan; Noble-Blair, Mishelle; Furst, Kirin; Spiesman, Anne; Kaushal, Sujay; Dadiala, Rhea; Bhide, Shantanu V.; Rippy, Megan A.; Curtis, Shannon; Grant, Stanley B. (2026)
A major barrier to preventing per- and polyfluoroalkyl substances (PFAS) from entering drinking water supplies is identifying and quantifying their upstream sources, particularly in One Water systems that integrate diverse water inputs. Here we combine high-frequency measurements with mass-balance analysis to quantify PFAS and major-ion loading to the Occoquan Reservoir, a drinkingwater supply serving one million people in Northern Virginia, USA. Mass-balance analysis at the confluence of watershed inflows and treated wastewater inputs reveals seasonally varying contributions from domestic wastewater, watershed runoff, and a single significant industrial user (SIU) of the sanitary sewer system. A one-month, system-scale diversion of SIU effluent confirms this source attribution for several short-chain PFAS and major ions, with concentration deficits closely matching withheld mass. These results demonstrate that traditional mass-balance approaches can inform collaborative management of PFAS contamination in One Water systems.
Análise descritiva por ordenação na caracterização sensorial de iogurte diet sabor morango enriquecido com concentrado protéico do soro
Loures, Milene Moreira Ribeiro; Minim, Valéria Paula Rodrigues; Ceresino, Elaine Berger; Carneiro, Renata C. V.; Minim, Luis Antonio (Universidade Estadual de Londrina, 2010)
Este estudo avaliou as características sensoriais de iogurte diet sabor morango enriquecidos com concentrado protéico de soro (CPS). Três formulações contendo 0,5%, 1% e 1,5% de CPS (F2, F3 e F4 em ordem crescente de concentração) e uma formulação controle sem adição de CPS (F1) foram desenvolvidas e avaliadas por meio da Análise Descritiva por Ordenação. Vinte provadores selecionados e treinados avaliaram as amostras caracterizadas pelos atributos: cor rosa, viscosidade, aroma característico de iogurte de morango, sabor característico de iogurte de morango, gosto doce, gosto ácido e consistência. As formulações diferiram significativamente (p < 0.05) nos atributos gosto doce e consistência. As amostras F3 e F4 apresentaram maior consistência confirmando a eficiência do CPS no aumento da consistência.
RAPID Enabled Physics-Based Neural Networks for Predicting 3-D Fission Distributions in JSI TRIGA Reactor
Franck, Timothy; Haghighat, Alireza; Snoj, Luka (2026-04-23)
The current methods for high-fidelity simulations of nuclear reactor systems are complex and computationally expensive. To reduce computation time, artificial intelligence (AI) and machine learning (ML) are being considered. Despite showing promise for solving various neutronics problems, the limited availability of high-fidelity data constrains ML applications to simpler problems or systems. This paper utilizes the RAPID code system for its effectiveness at rapidly producing large quantities of high-fidelity data. This has enabled the development of physics-based neural networks (NN) to predict 3-D fission distributions as a function of CR positions for the JSI TRIGA Mark-II research reactor. We developed a NN architecture that contains two hidden layers, 4400 neurons per hidden layer, with Leaky ReLU activation functions. This model was capable of predicting more than 99% of the fission values in the fuel elements within ±0.5% rel. diff. The model also predicted about 98% of the fission values in the fuel followers within ±10% rel. diff. It was determined that errors in the fuel follower predictions did not significantly impact calculated power peaking factors, which fell within the range of -0.39% to 0.91% rel. diff. Hyperparameter tuning and its effect on model performance is also discussed, with some comparisons to simpler ML models developed in a previous study.