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1. Evaluating f‑Orbital Participation in the UVE Multiple Bonds of [U(E)(NR2)3] (E = O, NSiMe3, NAd; R = SiMe3)

Author

Nguyen, Thien H, Paul, Edward L, Lukens, Wayne W, and Hayton, Trevor W

Subjects
Inorganic Chemistry, Chemical Sciences, 2.0 TEST, Physical Chemistry (incl. Structural), Other Chemical Sciences, Inorganic & Nuclear Chemistry, Inorganic chemistry, Macromolecular and materials chemistry
Abstract

The reaction of 1 equiv of 1-azidoadamantane with [UIII(NR2)3] (R = SiMe3) in Et2O results in the formation of [UV(NR2)3(NAd)] (1, Ad = 1-adamantyl) in good yields. The electronic structure of 1, as well as those of the related U(V) complexes, [UV(NR2)3(NSiMe3)] (2) and [UV(NR2)3(O)] (3), were analyzed with EPR spectroscopy, SQUID magnetometry, NIR-visible spectroscopy, and crystal field modeling. This analysis revealed that, within this series of complexes, the steric bulk of the E2- (E═O, NR) ligand is the most important factor in determining the electronic structure. In particular, the increasing steric bulk of this ligand, on moving from O2- to [NAd]2-, results in increasing U═E distances and E-U-Namide angles. These changes have two principal effects on the resulting electronic structure: (1) the increasing U═E distances decreases the energy of the fσ orbital, which is primarily σ* with respect to the U═E bond, and (2) the increasing E-U-Namide angles increases the energy of fδ, due to increasing antibonding interactions with the amide ligands. As a result of the latter change, the electronic ground state for complexes 1 and 2 is primarily fφ in character, whereas the ground state for complex 3 is primarily fδ.

Published
2023

3. The Curious Case of [AnH(NR2)3] (An = Th, U; R = SiMe3): Two Monomeric Actinide Hydrides Revisited

Author

Nguyen, Thien H., Ausman, Samantha F., MacGregor, Frank, Wu, Guang, Fortier, Skye, and Hayton, Trevor W.

Abstract

The reaction of AnCl4(DME)x(An = Th, x= 2; An = U, x= 0) with 4 equiv of NaNR2(R = SiMe3) in THF at 65 °C results in the formation of [An{N(R)(SiMe2CH2)}(NR2)2] (An = U, 1; An = Th, 2), and not the reported monomeric actinide hydrides, [AnH(NR2)3], as expected. Both complexes 1and 2were characterized by X-ray crystallography. Surprisingly, their unit cell parameters are remarkably close to those reported for [AnH(NR2)3], suggesting that the original crystals of [AnH(NR2)3] were, in fact, [An{N(R)(SiMe2CH2)}(NR2)2], but were misidentified. Reduction of 1with 1.1 equiv of KC8in THF, in the presence of 1 equiv of 2.2.2-cryptand, results in the formation of [K(2.2.2-cryptand)][U{N(R)(SiMe2CH2)}(NR2)2] (3) in good yield. Likewise, the reaction of 1with 1 equiv of bis(diisopropylamino)cyclopropenylidene (BAC) results in the formation of the BAC adduct, [(BAC)U{N(R)(SiMe2CH2)}(NR2)2] (4), in moderate yield. Finally, the addition of H2(10 bar) to 2in C6D6at room temperature results in the formation of the targeted monomeric hydride, [ThH(NR2)3], in 32% yield, according to integrations against an internal standard. However, removal of the H2atmosphere results in rapid reformation of 2. In contrast, the addition of H2(10 bar) to 1in C6D6at room temperature results in no apparent reaction.

Published
2025
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9. Characterization of Odorants in a Commercial Culinary Sage (Salvia officinalisL.) and Several Cultivars

Author

Chiang, Nancy, Dein, Melissa, Nguyen, Thien H., Trudelle, Danielle M., Ho, Chi-Tang, and Munafo, John P.

Abstract

Culinary sage, Salvia officinalisL., is a popular spice plant commonly used throughout the world. In this study, 35 odorants were identified in dried sage via solvent-assisted flavor evaporation (SAFE) and aroma extract dilution analysis (AEDA), including 9 that were identified in sage for the first time. Fifteen odorants were quantitated by stable isotope dilution analysis (SIDA), and their odor activity values (OAVs) were determined. Odorants with high OAVs included (2E,6Z)-nona-2,6-dienal, 1,8-cineole, and β-myrcene. A formulated aroma simulation model closely matched the aroma profile of an aqueous infusion of dried sage. Enantiomeric proportions of selected odorants were determined by chiral gas chromatography. Furthermore, 6 different sage cultivars were grown in the greenhouse, dried under the same conditions, and analyzed. Sensory analysis determined that all cultivars were dominated by an herbaceous sensory attribute and had varying intensities of eucalyptus, mint, clove, pine, green, earthy, floral, and citrus notes. Cultivars with varying intensities of herbaceous, eucalyptus, pine, and green sensory notes correlated with the OAVs of α-thujone/β-thujone, 1,8-cineole, α-pinene, and (2E,6Z)-nona-2,6-dienal, respectively. This study identified the odorants driving the sensory profiles of different sage cultivars and serves as a foundation for future studies on the aroma chemistry of culinary sage.

Published
2024
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12. Dimerization and ring-opening in bis(diisopropylamino)cyclopropenylidene (BAC) mediated by [U(NR2)3(CCPh)] (R = SiMe3).

Author

Nguyen, Thien H., Pauly, Christophe, Kent, Greggory T., Wu, Guang, and Hayton, Trevor W.

Subjects
*DIMERIZATION, *PROTON transfer reactions, *X-ray crystallography, *X-ray spectroscopy, *NUCLEAR magnetic resonance spectroscopy, *MOLECULES
Abstract

Addition of 2 equiv. of bis(diisopropylamino)cyclopropenylidene (BAC) to [U(NR2)3(CCPh)] (1, R = SiMe3), in Et2O, results in formation of [cyclo-N(iPr)C(Me)2CH(NiPr2)C{＝CHC3(NiPr2)2}][U(NR2)2(N(SiMe3)SiMe2CH2)(CCPh)] (2) in moderate isolated yield. Complex 2 is the result of coupling and protonation of two BAC molecules, where complex 1 contributes the required proton. It was characterized by NMR spectroscopy and X-ray crystallography and represents a new mode of reactivity of the cyclopropenylidene fragment. [ABSTRACT FROM AUTHOR]

Published
2023
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13. Dimerization and ring-opening in bis(diisopropylamino)cyclopropenylidene (BAC) mediated by [U(NR2)3(CCPh)] (R = SiMe3).

Author

Nguyen, Thien H., Pauly, Christophe, Kent, Greggory T., Wu, Guang, and Hayton, Trevor W.

Subjects
DIMERIZATION, PROTON transfer reactions, X-ray crystallography, X-ray spectroscopy, NUCLEAR magnetic resonance spectroscopy, MOLECULES
Abstract

Addition of 2 equiv. of bis(diisopropylamino)cyclopropenylidene (BAC) to [U(NR2)3(CCPh)] (1, R = SiMe3), in Et2O, results in formation of [cyclo-N(iPr)C(Me)2CH(NiPr2)C{＝CHC3(NiPr2)2}][U(NR2)2(N(SiMe3)SiMe2CH2)(CCPh)] (2) in moderate isolated yield. Complex 2 is the result of coupling and protonation of two BAC molecules, where complex 1 contributes the required proton. It was characterized by NMR spectroscopy and X-ray crystallography and represents a new mode of reactivity of the cyclopropenylidene fragment. [ABSTRACT FROM AUTHOR]

Published
2023
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19. NTU VIRAL: A visual-inertial-ranging-lidar dataset, from an aerial vehicle viewpoint.

Author

Nguyen, Thien-Minh, Yuan, Shenghai, Cao, Muqing, Lyu, Yang, Nguyen, Thien H, and Xie, Lihua

Subjects
AUTONOMOUS robots, AUTONOMOUS vehicles, ELEVATING platforms, AUTOMOBILE driving, ACQUISITION of data, DRIVERLESS cars
Abstract

In recent years, autonomous robots have become ubiquitous in research and daily life. Among many factors, public datasets play an important role in the progress of this field, as they waive the tall order of initial investment in hardware and manpower. However, for research on autonomous aerial systems, there appears to be a relative lack of public datasets on par with those used for autonomous driving and ground robots. Thus, to fill in this gap, we conduct a data collection exercise on an aerial platform equipped with an extensive and unique set of sensors: two 3D lidars, two hardware-synchronized global-shutter cameras, multiple Inertial Measurement Units (IMUs), and especially, multiple Ultra-wideband (UWB) ranging units. The comprehensive sensor suite resembles that of an autonomous driving car, but features distinct and challenging characteristics of aerial operations. We record multiple datasets in several challenging indoor and outdoor conditions. Calibration results and ground truth from a high-accuracy laser tracker are also included in each package. All resources can be accessed via our webpage https://ntu-aris.github.io/ntu_viral_dataset/. [ABSTRACT FROM AUTHOR]

Published
2022
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20. Expression-Based Cell Lineage Analysis inDrosophilaThrough a Course-Based Research Experience for Early Undergraduates

Author

Olson, John M, primary, Evans, Cory J, additional, Ngo, Kathy T, additional, Kim, Hee Jong, additional, Nguyen, Joseph Duy, additional, Gurley, Kayla G H, additional, Ta, Truc, additional, Patel, Vijay, additional, Han, Lisa, additional, Truong-N, Khoa T, additional, Liang, Letty, additional, Chu, Maggie K, additional, Lam, Hiu, additional, Ahn, Hannah G, additional, Banerjee, Abhik Kumar, additional, Choi, In Young, additional, Kelley, Ross G, additional, Moridzadeh, Naseem, additional, Khan, Awais M, additional, Khan, Omair, additional, Lee, Szuyao, additional, Johnson, Elizabeth B, additional, Tigranyan, Annie, additional, Wang, Jay, additional, Gandhi, Anand D, additional, Padhiar, Manish M, additional, Calvopina, Joseph Hargan, additional, Sumra, Kirandeep, additional, Ou, Kristy, additional, Wu, Jessie C, additional, Dickan, Joseph N, additional, Ahmadi, Sabrena M, additional, Allen, Donald N, additional, Mai, Van Thanh, additional, Ansari, Saif, additional, Yeh, George, additional, Yoon, Earl, additional, Gon, Kimberly, additional, Yu, John Y, additional, He, Johnny, additional, Zaretsky, Jesse M, additional, Lee, Noemi E, additional, Kuoy, Edward, additional, Patananan, Alexander N, additional, Sitz, Daniel, additional, Tran, PhuongThao, additional, Do, Minh-Tu, additional, Akhave, Samira J, additional, Alvarez, Silverio D, additional, Asem, Bobby, additional, Asem, Neda, additional, Azarian, Nicole A, additional, Babaesfahani, Arezou, additional, Bahrami, Ahmad, additional, Bhamra, Manjeet, additional, Bhargava, Ragini, additional, Bhatia, Rakesh, additional, Bhatia, Subir, additional, Bumacod, Nicholas, additional, Caine, Jonathan J, additional, Caldwell, Thomas A, additional, Calica, Nicole A, additional, Calonico, Elise M, additional, Chan, Carman, additional, Chan, Helen H-L, additional, Chang, Albert, additional, Chang, Chiaen, additional, Chang, Daniel, additional, Chang, Jennifer S, additional, Charania, Nauman, additional, Chen, Jasmine Y, additional, Chen, Kevin, additional, Chen, Lu, additional, Chen, Yuyu, additional, Cheung, Derek J, additional, Cheung, Jesse J, additional, Chew, Jessica J, additional, Chew, Nicole B, additional, Chien, Cheng-An Tony, additional, Chin, Alana M, additional, Chin, Chee Jia, additional, Cho, Youngho, additional, Chou, Man Ting, additional, Chow, Ke-Huan K, additional, Chu, Carolyn, additional, Chu, Derrick M, additional, Chu, Virginia, additional, Chuang, Katherine, additional, Chugh, Arunit Singh, additional, Cubberly, Mark R, additional, Daniel, Michael Guillermo, additional, Datta, Sangita, additional, Dhaliwal, Raj, additional, Dinh, Jenny, additional, Dixit, Dhaval, additional, Dowling, Emmylou, additional, Feng, Melinda, additional, From, Christopher M, additional, Furukawa, Daisuke, additional, Gaddipati, Himaja, additional, Gevorgyan, Lilit, additional, Ghaznavi, Zunera, additional, Ghosh, Tulika, additional, Gill, Jaskaran, additional, Groves, David J, additional, Gurara, Kalkidan K, additional, Haghighi, Ali R, additional, Havard, Alexandra L, additional, Heyrani, Nasser, additional, Hioe, Tanya, additional, Hong, Kirim, additional, Houman, Justin J, additional, Howland, Molly, additional, Hsia, Elaine L, additional, Hsueh, Justin, additional, Hu, Stacy, additional, Huang, Andrew J, additional, Huynh, Jasmine C, additional, Huynh, Jenny, additional, Iwuchukwu, Chris, additional, Jang, Michael J, additional, Jiang, An An, additional, Kahlon, Simran, additional, Kao, Pei-Yun, additional, Kaur, Manpreet, additional, Keehn, Matthew G, additional, Kim, Elizabeth J, additional, Kim, Hannah, additional, Kim, Michelle J, additional, Kim, Shawn J, additional, Kitich, Aleksandar, additional, Kornberg, Ross A, additional, Kouzelos, Nicholas G, additional, Kuon, Jane, additional, Lau, Bryan, additional, Lau, Roger K, additional, Law, Rona, additional, Le, Huy D, additional, Le, Rachael, additional, Lee, Carrou, additional, Lee, Christina, additional, Lee, Grace E, additional, Lee, Kenny, additional, Lee, Michelle J, additional, Lee, Regina V, additional, Lee, Sean H K, additional, Lee, Sung Kyu, additional, Lee, Sung-Ling D, additional, Lee, Yong Jun, additional, Leong, Megan J, additional, Li, David M, additional, Li, Hao, additional, Liang, Xingfu, additional, Lin, Eric, additional, Lin, Michelle M, additional, Lin, Peter, additional, Lin, Tiffany, additional, Lu, Stacey, additional, Luong, Serena S, additional, Ma, Jessica S, additional, Ma, Li, additional, Maghen, Justin N, additional, Mallam, Sravya, additional, Mann, Shivtaj, additional, Melehani, Jason H, additional, Miller, Ryan C, additional, Mittal, Nitish, additional, Moazez, Carmel M, additional, Moon, Susie, additional, Moridzadeh, Rameen, additional, Ngo, Kaley, additional, Nguyen, Hanh H, additional, Nguyen, Kambria, additional, Nguyen, Thien H, additional, Nieh, Angela W, additional, Niu, Isabella, additional, Oh, Seo-Kyung, additional, Ong, Jessica R, additional, Oyama, Randi K, additional, Park, Joseph, additional, Park, Yaelim A, additional, Passmore, Kimberly A, additional, Patel, Ami, additional, Patel, Amy A, additional, Patel, Dhruv, additional, Patel, Tirth, additional, Peterson, Katherine E, additional, Pham, An Huynh, additional, Pham, Steven V, additional, Phuphanich, Melissa E, additional, Poria, Neil D, additional, Pourzia, Alexandra, additional, Ragland, Victoria, additional, Ranat, Riki D, additional, Rice, Cameron M, additional, Roh, David, additional, Rojhani, Solomon, additional, Sadri, Lili, additional, Saguros, Agafe, additional, Saifee, Zainab, additional, Sandhu, Manjot, additional, Scruggs, Brooke, additional, Scully, Lisa M, additional, Shih, Vanessa, additional, Shin, Brian A, additional, Sholklapper, Tamir, additional, Singh, Harnek, additional, Singh, Sumedha, additional, Snyder, Sondra L, additional, Sobotka, Katelyn F, additional, Song, Sae Ho, additional, Sukumar, Siddharth, additional, Sullivan, Halley C, additional, Sy, Mark, additional, Tan, Hande, additional, Taylor, Sara K, additional, Thaker, Shivani K, additional, Thakore, Tulsi, additional, Tong, Gregory E, additional, Tran, Jacinda N, additional, Tran, Jonathan, additional, Tran, Tuan D, additional, Tran, Vivi, additional, Trang, Cindy L, additional, Trinh, Hung G, additional, Trinh, Peter, additional, Tseng, Han-Ching H, additional, Uotani, Ted T, additional, Uraizee, Akram V, additional, Vu, Kent K T, additional, Vu, Kevin K T, additional, Wadhwani, Komal, additional, Walia, Paluk K, additional, Wang, Rebecca S, additional, Wang, Shuo, additional, Wang, Stephanie J, additional, Wiredja, Danica D, additional, Wong, Andrew L, additional, Wu, Daniel, additional, Xue, Xi, additional, Yanez, Griselda, additional, Yang, Yung-Hsuan, additional, Ye, Zhong, additional, Yee, Victor W, additional, Yeh, Cynthia, additional, Zhao, Yue, additional, Zheng, Xin, additional, Ziegenbalg, Anke, additional, Alkali, Jon, additional, Azizkhanian, Ida, additional, Bhakta, Akash, additional, Berry, Luke, additional, Castillo, Ryen, additional, Darwish, Sonja, additional, Dickinson, Holly, additional, Dutta, Ritika, additional, Ghosh, Rahul Kumar, additional, Guerin, Riley, additional, Hofman, Jonathan, additional, Iwamoto, Garrick, additional, Kang, Sarah, additional, Kim, Andrew, additional, Kim, Brian, additional, Kim, Hanwool, additional, Kim, Kristine, additional, Kim, Suji, additional, Ko, Julie, additional, Koenig, Michael, additional, LaRiviere, Alejandro, additional, Lee, Clifton, additional, Lee, Jiwon, additional, Lung, Brandon, additional, Mittelman, Max, additional, Murata, Mark, additional, Park, Yujin, additional, Rothberg, Daniel, additional, Sprung-Keyser, Ben, additional, Thaker, Kunal, additional, Yip, Vivian, additional, Picard, Paul, additional, Diep, Francie, additional, Villarasa, Nikki, additional, Hartenstein, Volker, additional, Shapiro, Casey, additional, Levis-Fitzgerald, Marc, additional, Jaworski, Leslie, additional, Loppato, David, additional, Clark, Ira E, additional, and Banerjee, Utpal, additional

Published
2019
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23. Characterization of the “Absent” Vanadium Oxo V(═O){N(SiMe3)2}3, Imido V(═NSiMe3){N(SiMe3)2}3, and Imido-Siloxy V(═NSiMe3)(OSiMe3){N(SiMe3)2}2Complexes Derived from V{N(SiMe3)2}3and Kinetic Study of the Spontaneous Conversion of the Oxo Complex into Its Imido-Siloxy Isomer

Author

Stennett, Cary R., Nguyen, Thien H., and Power, Philip P.

Abstract

The synthesis and characterization of V(═O){N(SiMe3)2}3(1), V(═NSiMe3){N(SiMe3)2}3(2), and V(═NSiMe3)(OSiMe3){N(SiMe3)2}2(3) are described. Prior attempts to synthesize the vanadium(V) oxo complex 1via salt metathesis of VOCl3with the lithium or sodium silylamide salt had yielded either the putative rearranged species V(═NSiMe3)(OSiMe3){N(SiMe3)2}2(3) or the oxo-bridged, dimetallic {(μ-O)2V2[N(SiMe3)2]4}. We now show that complex 1is available by treatment of the vanadium(III) tris(silylamide) V{N(SiMe3)2}3with iodosylbenzene. The imido complex 2was obtained by treatment of V{N(SiMe3)2}3with trimethylsilyl azide. Sublimation of 1formed complex 3, which was determined to be V(═NSiMe3)(OSiMe3){N(SiMe3)2}2, on the basis of infrared, electronic, and 1H and 51V NMR spectroscopies. Crystallographic disorder precluded a complete structural characterization of 3, although a four-coordinate V atom, as well as severely disordered ligands, were apparent. Comparison of the vibrational spectra of 1and 2allowed an unambiguous assignment of the V–O (995 cm–1) and V–Nimide(1060 cm–1) stretching bands. The vibrational spectrum of complex 3displayed strong absorbances at 1090 and 945 cm–1, indicative of its metal imide and metal siloxide moieties. The 1H NMR spectrum of 1in deuterated benzene showed overlapping signals for the ligand protons proximal and distal to the oxo moiety at 0.52 and 0.38 ppm. The 1H NMR spectrum of 2in deuterated methylene chloride displayed distinct signals for the imido (0.41 ppm) and amido (0.35 ppm) protons, whereas 1H NMR spectroscopy of 3showed three signals in an intensity ratio consistent with the formula V(═NSiMe3)(OSiMe3){N(SiMe3)2}2. 51V NMR spectra of 1–3revealed singlet resonances at −119 ppm (1), −24 ppm (2), and −279 ppm (3). The electronic spectra of 1–3displayed single absorbances in the charge transfer region, consistent with their d0electron configurations. Kinetic studies of the spontaneous conversion of complex 1to 3were used to determine the rate constants (ca. 0.0002 s–1(63 °C), 0.0006 s–1(73 °C), 0.002 s–1(83 °C)) and activation energy (ca. 20 kcal/mol) of this first-order process.

Published
2020
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24. Isolating resistors form planar N-way power dividers

Author

Nguyen, Thien H. and Lam, Thomas

Subjects
Microwave transmission lines -- Equipment and supplies, Microwave devices -- Design and construction, Business, Electronics and electrical industries, Engineering and manufacturing industries
Published
1991

34. Evaluating f-Orbital Participation in the U V ═E Multiple Bonds of [U(E)(NR 2 ) 3 ] (E = O, NSiMe 3 , NAd; R = SiMe 3 ).

Author

Nguyen TH, Paul EL, Lukens WW, and Hayton TW

Abstract

The reaction of 1 equiv of 1-azidoadamantane with [U III (NR 2 ) 3 ] (R = SiMe 3 ) in Et 2 O results in the formation of [U V (NR 2 ) 3 (NAd)] ( 1 , Ad = 1-adamantyl) in good yields. The electronic structure of 1 , as well as those of the related U(V) complexes, [U V (NR 2 ) 3 (NSiMe 3 )] ( 2 ) and [U V (NR 2 ) 3 (O)] ( 3 ), were analyzed with EPR spectroscopy, SQUID magnetometry, NIR-visible spectroscopy, and crystal field modeling. This analysis revealed that, within this series of complexes, the steric bulk of the E 2- (E═O, NR) ligand is the most important factor in determining the electronic structure. In particular, the increasing steric bulk of this ligand, on moving from O 2- to [NAd] 2- , results in increasing U═E distances and E-U-N amide angles. These changes have two principal effects on the resulting electronic structure: (1) the increasing U═E distances decreases the energy of the f σ orbital, which is primarily σ* with respect to the U═E bond, and (2) the increasing E-U-N amide angles increases the energy of f δ , due to increasing antibonding interactions with the amide ligands. As a result of the latter change, the electronic ground state for complexes 1 and 2 is primarily f φ in character, whereas the ground state for complex 3 is primarily f δ .

Published
2023
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35. Characterization of the "Absent" Vanadium Oxo V(═O){N(SiMe 3 ) 2 } 3 , Imido V(═NSiMe 3 ){N(SiMe 3 ) 2 } 3 , and Imido-Siloxy V(═NSiMe 3 )(OSiMe 3 ){N(SiMe 3 ) 2 } 2 Complexes Derived from V{N(SiMe 3 ) 2 } 3 and Kinetic Study of the Spontaneous Conversion of the Oxo Complex into Its Imido-Siloxy Isomer.

Author

Stennett CR, Nguyen TH, and Power PP

Abstract

The synthesis and characterization of V(═O){N(SiMe 3 ) 2 } 3 ( 1 ), V(═NSiMe 3 ){N(SiMe 3 ) 2 } 3 ( 2 ), and V(═NSiMe 3 )(OSiMe 3 ){N(SiMe 3 ) 2 } 2 ( 3 ) are described. Prior attempts to synthesize the vanadium(V) oxo complex 1 via salt metathesis of VOCl 3 with the lithium or sodium silylamide salt had yielded either the putative rearranged species V(═NSiMe 3 )(OSiMe 3 ){N(SiMe 3 ) 2 } 2 ( 3 ) or the oxo-bridged, dimetallic {(μ-O) 2 V 2 [N(SiMe 3 ) 2 ] 4 }. We now show that complex 1 is available by treatment of the vanadium(III) tris(silylamide) V{N(SiMe 3 ) 2 } 3 with iodosylbenzene. The imido complex 2 was obtained by treatment of V{N(SiMe 3 ) 2 } 3 with trimethylsilyl azide. Sublimation of 1 formed complex 3 , which was determined to be V(═NSiMe 3 )(OSiMe 3 ){N(SiMe 3 ) 2 } 2 , on the basis of infrared, electronic, and 1 H and 51 V NMR spectroscopies. Crystallographic disorder precluded a complete structural characterization of 3 , although a four-coordinate V atom, as well as severely disordered ligands, were apparent. Comparison of the vibrational spectra of 1 and 2 allowed an unambiguous assignment of the V-O (995 cm -1 ) and V-N imide (1060 cm -1 ) stretching bands. The vibrational spectrum of complex 3 displayed strong absorbances at 1090 and 945 cm -1 , indicative of its metal imide and metal siloxide moieties. The 1 H NMR spectrum of 1 in deuterated benzene showed overlapping signals for the ligand protons proximal and distal to the oxo moiety at 0.52 and 0.38 ppm. The 1 H NMR spectrum of 2 in deuterated methylene chloride displayed distinct signals for the imido (0.41 ppm) and amido (0.35 ppm) protons, whereas 1 H NMR spectroscopy of 3 showed three signals in an intensity ratio consistent with the formula V(═NSiMe 3 )(OSiMe 3 ){N(SiMe 3 ) 2 } 2 . 51 V NMR spectra of 1 - 3 revealed singlet resonances at -119 ppm ( 1 ), -24 ppm ( 2 ), and -279 ppm ( 3 ). The electronic spectra of 1 - 3 displayed single absorbances in the charge transfer region, consistent with their d 0 electron configurations. Kinetic studies of the spontaneous conversion of complex 1 to 3 were used to determine the rate constants (ca. 0.0002 s -1 (63 °C), 0.0006 s -1 (73 °C), 0.002 s -1 (83 °C)) and activation energy (ca. 20 kcal/mol) of this first-order process.

Published
2020
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36. Expression-Based Cell Lineage Analysis in Drosophila Through a Course-Based Research Experience for Early Undergraduates.

Author

Olson JM, Evans CJ, Ngo KT, Kim HJ, Nguyen JD, Gurley KGH, Ta T, Patel V, Han L, Truong-N KT, Liang L, Chu MK, Lam H, Ahn HG, Banerjee AK, Choi IY, Kelley RG, Moridzadeh N, Khan AM, Khan O, Lee S, Johnson EB, Tigranyan A, Wang J, Gandhi AD, Padhiar MM, Calvopina JH, Sumra K, Ou K, Wu JC, Dickan JN, Ahmadi SM, Allen DN, Mai VT, Ansari S, Yeh G, Yoon E, Gon K, Yu JY, He J, Zaretsky JM, Lee NE, Kuoy E, Patananan AN, Sitz D, Tran P, Do MT, Akhave SJ, Alvarez SD, Asem B, Asem N, Azarian NA, Babaesfahani A, Bahrami A, Bhamra M, Bhargava R, Bhatia R, Bhatia S, Bumacod N, Caine JJ, Caldwell TA, Calica NA, Calonico EM, Chan C, Chan HH, Chang A, Chang C, Chang D, Chang JS, Charania N, Chen JY, Chen K, Chen L, Chen Y, Cheung DJ, Cheung JJ, Chew JJ, Chew NB, Chien CT, Chin AM, Chin CJ, Cho Y, Chou MT, Chow KK, Chu C, Chu DM, Chu V, Chuang K, Chugh AS, Cubberly MR, Daniel MG, Datta S, Dhaliwal R, Dinh J, Dixit D, Dowling E, Feng M, From CM, Furukawa D, Gaddipati H, Gevorgyan L, Ghaznavi Z, Ghosh T, Gill J, Groves DJ, Gurara KK, Haghighi AR, Havard AL, Heyrani N, Hioe T, Hong K, Houman JJ, Howland M, Hsia EL, Hsueh J, Hu S, Huang AJ, Huynh JC, Huynh J, Iwuchukwu C, Jang MJ, Jiang AA, Kahlon S, Kao PY, Kaur M, Keehn MG, Kim EJ, Kim H, Kim MJ, Kim SJ, Kitich A, Kornberg RA, Kouzelos NG, Kuon J, Lau B, Lau RK, Law R, Le HD, Le R, Lee C, Lee C, Lee GE, Lee K, Lee MJ, Lee RV, Lee SHK, Lee SK, Lee SD, Lee YJ, Leong MJ, Li DM, Li H, Liang X, Lin E, Lin MM, Lin P, Lin T, Lu S, Luong SS, Ma JS, Ma L, Maghen JN, Mallam S, Mann S, Melehani JH, Miller RC, Mittal N, Moazez CM, Moon S, Moridzadeh R, Ngo K, Nguyen HH, Nguyen K, Nguyen TH, Nieh AW, Niu I, Oh SK, Ong JR, Oyama RK, Park J, Park YA, Passmore KA, Patel A, Patel AA, Patel D, Patel T, Peterson KE, Pham AH, Pham SV, Phuphanich ME, Poria ND, Pourzia A, Ragland V, Ranat RD, Rice CM, Roh D, Rojhani S, Sadri L, Saguros A, Saifee Z, Sandhu M, Scruggs B, Scully LM, Shih V, Shin BA, Sholklapper T, Singh H, Singh S, Snyder SL, Sobotka KF, Song SH, Sukumar S, Sullivan HC, Sy M, Tan H, Taylor SK, Thaker SK, Thakore T, Tong GE, Tran JN, Tran J, Tran TD, Tran V, Trang CL, Trinh HG, Trinh P, Tseng HH, Uotani TT, Uraizee AV, Vu KKT, Vu KKT, Wadhwani K, Walia PK, Wang RS, Wang S, Wang SJ, Wiredja DD, Wong AL, Wu D, Xue X, Yanez G, Yang YH, Ye Z, Yee VW, Yeh C, Zhao Y, Zheng X, Ziegenbalg A, Alkali J, Azizkhanian I, Bhakta A, Berry L, Castillo R, Darwish S, Dickinson H, Dutta R, Ghosh RK, Guerin R, Hofman J, Iwamoto G, Kang S, Kim A, Kim B, Kim H, Kim K, Kim S, Ko J, Koenig M, LaRiviere A, Lee C, Lee J, Lung B, Mittelman M, Murata M, Park Y, Rothberg D, Sprung-Keyser B, Thaker K, Yip V, Picard P, Diep F, Villarasa N, Hartenstein V, Shapiro C, Levis-Fitzgerald M, Jaworski L, Loppato D, Clark IE, and Banerjee U

Subjects
Animals, Brain, Eye, Gene Expression, Lymphatic System, Research, Students, Universities, Wings, Animal, Cell Lineage, Drosophila genetics
Abstract

A variety of genetic techniques have been devised to determine cell lineage relationships during tissue development. Some of these systems monitor cell lineages spatially and/or temporally without regard to gene expression by the cells, whereas others correlate gene expression with the lineage under study. The G AL4 T echnique for R eal-time a nd C lonal E xpression (G-TRACE) system allows for rapid, fluorescent protein-based visualization of both current and past GAL4 expression patterns and is therefore amenable to genome-wide expression-based lineage screens. Here we describe the results from such a screen, performed by undergraduate students of the University of California, Los Angeles (UCLA) Undergraduate Research Consortium for Functional Genomics (URCFG) and high school summer scholars as part of a discovery-based education program. The results of the screen, which reveal novel expression-based lineage patterns within the brain, the imaginal disc epithelia, and the hematopoietic lymph gland, have been compiled into the G-TRACE Expression Database (GED), an online resource for use by the Drosophila research community. The impact of this discovery-based research experience on student learning gains was assessed independently and shown to be greater than that of similar programs conducted elsewhere. Furthermore, students participating in the URCFG showed considerably higher STEM retention rates than UCLA STEM students that did not participate in the URCFG, as well as STEM students nationwide., (Copyright © 2019 Olson et al.)

Published
2019
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