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Recent Submissions

Cancer Cell Targeting Via Selective Transferrin Receptor Labeling Using Protein-Derived Carbon Dots
(2024) Strickland, Sara (TTU); Jorns, Mychele (TTU); Fourroux, Luke (TTU); Heyd, Lindsey (TTU); Pappas, Dimitri (TTU)
Carbon dot (CD) nanoparticles offer tremendous advantages as fluorescent probes in bioimaging and biosensing; however, they lack specific affinity for biomolecules, limiting their practical applications in selective targeting. Nanoparticles with intrinsic affinity for a target have applications in imaging, cytometry, therapeutics, etc. Toward that end, we report the transferrin receptor (CD71) targeting CDs, synthesized for the first time. The formation of these particles is truly groundbreaking, as direct tuning of nanoparticle affinity was achieved by simple and careful precursor selection of a protein, which has the targeting characteristic of interest. We hypothesized that the retention of the original protein’s peptides on the nanoparticle surface provides the CDs with some of the function of the precursor protein, enabling selective binding to the protein’s receptor. This was confirmed with FTIR (Fourier transform infrared) data and subsequent affinity-based cell assays. These transferrin (Tf)-derived CDs have been shown to possess an affinity for CD71, a cancer biomarker that is ubiquitously expressed in nearly every cancer cell line due to its central role mediating the uptake of cellular iron. The CDs were tested using the human leukemia cell line HL60 and demonstrated the selective targeting of CD71 and specific triggering of transferrin-mediated endocytosis via clathrin-coated pits. The particle characterization results reflect a carbon-based nanoparticle with bright violet fluorescence and 7.9% quantum yield in aqueous solution. These unpresented CDs proved to retain the functional properties of the precursor protein. Indicating that this process can be repeated for other disease biomarkers for applications ranging from biosensing and diagnostic bioimaging to targeted therapeutics.
Who Shot the Bullet? Projectile Composition Characterization as an Evolutionary Method for Enhancement of Ballistics Evidence Analysis
(2023) Newland, Ashley (TTU); Banks, Emilynn (TTU); Halámek, Jan (TTU)
Toolmark and Firearm examiners’ opinions have fallen under scrutiny as inadmissible ballistics evidence has led to the possibility of wrongful convictions and cold cases that could have been solved with the presence of a physical bullet, casing, and/or weapon at the crime scene. This research provides a solution for subjective-based conclusions and the absence of physical evidence altogether. Analysis of bullet material using Atomic Absorption Spectroscopy (AAS) has distinguished bullet composition between manufacturers from a surface scratch. This provides proof of concept that, when a bullet strikes a surface, metal deposits can be extracted and analyzed to corroborate microscopy techniques that currently violate Daubert criteria. Further studies could also provide results to distinguish barrel manufacturers from fired bullets and casings. This novel method of analysis can pave the way for crime scene collection procedures in the absence of physical evidence and provide an increase in scientific value to the expert’s conclusions.
Enhanced phenylpropanoid metabolism underlies resistance to Fusarium oxysporum f. sp. vasinfectum race 4 infection in the cotton cultivar Pima-S6 (Gossypium barbadense L.)
(2023) Ojeda-Rivera, Jonathan Odilón (TTU); Ulloa, Mauricio; Pérez-Zavala, Francisco G. (TTU); Nájera-González, Héctor Rogelio (TTU); Roberts, Philip A.; Yong-Villalobos, Lenin (TTU); Yadav, Himanshu (TTU); Chávez Montes, Ricardo A. (TTU); Herrera-Estrella, Luis (TTU); Lopez-Arredondo, Damar (TTU)
Introduction: Fusarium oxysporum f. sp. vasinfectum (FOV) race 4 (FOV4) is a highly pathogenic soil-borne fungus responsible for Fusarium wilt in cotton (Gossypium spp.) and represents a continuing threat to cotton production in the southwest states of the United States, including California, New Mexico, and Texas. Pima (G. barbadense L.) cotton, which is highly valued for its fiber quality, has been shown to be more susceptible to this pathogen than Upland (G. hirsutum L.) cotton. Still, some Pima cultivars present resistance to FOV4 infection. Methods: To gain insights into the FOV4-resistance mechanism, we performed comparative transcriptional and metabolomic analyses between FOV4-susceptible and FOV4-resistant Pima cotton entries. FOV4-resistant Pima-S6 and FOV4-susceptible Pima S-7 and Pima 3-79 cotton plants were infected with FOV4 in the greenhouse, and the roots harvested 11 days post-infection for further analysis. Results: We found that an enhanced root phenylpropanoid metabolism in the resistant Pima-S6 cultivar determines FOV4-resistance. Gene-ontology enrichment of phenylpropanoid biosynthesis and metabolism categories correlated with the accumulation of secondary metabolites in Pima-S6 roots. Specifically, we found esculetin, a coumarin, an inhibitor of Fusarium’s growth, accumulated in the roots of Pima-S6 even under non-infected conditions. Genes related to the phenylpropanoid biosynthesis and metabolism, including phenylalanine ammonia-lyase 2 (PAL2) and pleiotropic drug resistance 12 (PDR12) transporter, were found to be upregulated in Pima-S6 roots. Discussion: Our results highlight an essential role for the phenylpropanoid synthesis pathway in FOV4 resistance in Pima-S6 cotton. These genes represent attractive research prospects for FOV4-disease resistance and breeding approaches of other cotton cultivars of economic relevance.
Renewable energy resource assessment for rural electrification: a case study in Nepal
(2023) Sedai, Ashish (TTU); Dhakal, Rabin; Koirala, Pranik; Gautam, Shishir; Pokhrel, Rajat; Lohani, Sunil Prasad; Moussa, Hanna (TTU); Pol, Suhas (TTU)
Renewable energy could mitigate remote area energy crises through rural electrification. Karnali province, one of the seven federal provinces of Nepal, is such a remote location and is most deprived in terms of electricity access. Around 67% of the population of the Karnali province is not connected to the national grid electricity supply. High altitude, mountainous topography makes it difficult to provide grid access to the region. This study summarizes the current electricity access status in Nepal and Karnali province specifically. The paper discusses the energy, economic and environmental (3E) analysis of different renewable energy resources like solar and wind energy for the grid-isolated region in Mugu and Jumla district of Karnali province. The study investigates the feasibility of a 200-kW solar power plant installation in Gamghadi, the capital of Mugu district and a 100-kW wind power plant installation in Tila village, Jumla district. The study suggests whether a similar installation of the distributed energy plant is a solution to mitigate the energy crisis problem in the high Himalayas regions, like Karnali province of Nepal. Based on the high-level resource assessment, the study estimates an investment cost ranging from 7 to 9 million USD would be necessary for the installation of such distributed solar PV and wind turbines.
The Narrative Identity of European Cities in Contemporary Literature
(2023) Novak, Sonja; Mehan, Asma (TTU); Çirakli, Mustafa Zeki; Quinteiro, Sílvia
This volume aimed to highlight narrative identities of European cities or city neighbourhoods that have been overlooked, such as mid-sized cities. These cities are neither small towns nor metropolises, cities that are now unveiling their appeal or specificity. The present special issue thus covers a range of representations of cities. The articles investigate more systematically how different texts deal with various cities from different experiential and fictional perspectives. The issue covers the geographical scope across Europe, from east to west or vice versa, as well as a range of different works of national literature(s), but with a clear emphasis on mid-sized European cities that have until now been deemed as lesser-known, secondary, peripheral, 'other' cities that are in the focus of the research of the COST project Writing Urban Places. New Narratives of the European City, within which this journal issue is being published.