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Visualizing Cancer Cells with High Fidelity Using Enzyme-Responsive Fluorescent Probes
No full textFluorescence imaging based on exogenous small-molecule probes may significantly impact diagnosis and treatment of cancer. However, its potential has yet to be attained due to limitations with probe selectivity and depth of image generation. Fidelity of fluorescence signal production to only those areas of tissue containing diseased cells is envisioned through use of molecular probes whose emission is altered or revealed upon a specific reaction between probe and intracellular targets. A major challenge to fulfill the great promise of fluorescence imaging for diagnosis and treatment of cancer is the development of responsive materials that signal the presence of key characteristics linked to diseased tissue and cells. A potentially impactful approach involves the use of intracellularly activated, small-molecule fluorescent probes that track and target a particular disease-linked enzyme with high selectivity and allow for visual inspection of enzyme activity presence with low levels of detection. To address this, fluorescent probes showing the capability to alter their emission energies, and amplification in their signal intensity by enzyme action, while also providing the necessary spectral window, are to be created. Efforts in the McCarley research group target the cancer biomarker hNQO1, human NAD(P)H: quinone oxidoreductase-1 enzyme, because of its overexpression in various patient-derived cancers and its cytoprotective effect on cancer cells, which is postulated to be involved with cancer treatment resistance and cellular escape mechanisms that lead to the spread of the disease. In this work, I have designed and synthesized three near-infrared fluorescent probes: Q3NCyN, Q3NNOMe, and Q3NBz, and demonstrated their ability to report on hNQO1 presence selectively and sensitively in 2-dimensional cell cultures. High selectivity of this overexpressed 2-electron-specific quinone reductase is ensured by the probes having a highly tuned quinone trigger group/motif whose reduction initiates subsequent bond-breaking release of fluorescent reporter, as demonstrated by optical and fluorescence spectroscopy. Confocal laser scanning microscopy and spinning disk microscopy experiments confirm highly selective and sensitive detection of the oxidoreductase in hNQO1-positive cell lines vs those devoid of or having limited hNQO1 expression. These probes show great potential for early tumor detection, relapses, and disease monitoring to reduce cancer mortality rates based on fluorescence imaging of cancer cells with upregulated hNQO1 enzyme
SEXOLOGY OTHERWISE, OR THE LITERARY STYLE OF REASONING
No full textIn his essay “The Literariness of Sexuality: Or, How to Do the (Literary) History of (American) Sexuality” (2013), Christopher Looby audaciously sidesteps the usual groundings of sexuality in material conditions and lived experiences to claim that “sexuality is essentially a literary phenomenon.”1 For Looby, the literariness of sexuality has three dimensions:“[S]exuality is itself a fiction,” which aggregates “bodily sensations, gender determinations, forms of sexual conduct, erotic scripts, and so on” into what Michel Foucault calls the “artificial unity” of sexuality. This “‘fictitious unity’” may be seen as a “stylization of the self” analogous (and even more than analogous) to the “stylization of literary language.” The historical co-emergence of sexuality and the literary public sphere suggests that sexuality needed a venue to be “articulated, promulgated, circulated, and encountered” and that the literary public sphere provided just such an arena.
In The Thick Of It
No full textIn this exhibition, In The Thick Of It, my paintings and sculptures serve as a visual diary of my experience moving to and navigating life in Louisiana. Through art, I document this new landscape and atmosphere, capturing my evolving emotional state, shifting focus, and emerging ideas. As an outsider, the process of discovery introduces layers of tension, curiosity, and fragmentations in my paintings. The spaces within my paintings reflect a constant flux, mirroring the ongoing adjustments to Louisiana’s cultural cues, history, and environment. The complexity of this rich yet challenging place permeates my art, creating dynamic, layered compositions that echo my adaptation and interpretation of my surroundings. Art becomes both a reflection of my personal experience and a tool for mapping my journey in an ever-changing environment
Advances in tropical climatology–a review
Get PDFUnderstanding tropical climatology is essential to comprehending the atmospheric connections between the tropics and extratropical latitudes weather and climate events. In this review paper, we emphasize the advances in key areas of tropical climatology knowledge since the end of the 20th century and offer a summary, assessment, and discussion of previously published literature. Among the key areas analyzed here, we explore the advances in tropical oceanic and atmospheric variability, such as El Niño–Southern Oscillation and the Madden-Julian Oscillation, and how those teleconnection events have helped us to better understand variabilities in tropical monsoons, tropical cyclones, and drought events. We also discuss new concepts incorporated into the study of tropical cyclones, such as rapid intensification, and how those studies are evolving and helping scientists to better prepare and predict hurricanes. Regarding tropical aerosols, we discuss how satellite-based dust detection has improved the comprehension of Saharan dust as a driver of drought in locations far from the dust source region while simultaneously altering tropical cyclone variability. Finally, our review shows that there have been significant advances in tropical hydroclimatic studies in order to better investigate monsoons, flooding, and drought, helping scholars of tropical climatology to better understand its extreme events
Visual programming-based Geospatial Cyberinfrastructure for open-source GIS education 3.0
No full textOpen-ource GIS plays a pivotal role in advancing GIS education, fostering research collaboration, and supporting global sustainability by enabling the sharing of data, models, and knowledge. However, the integration of big data, deep learning methods, and artificial intelligence deep learning in geospatial research presents significant challenges for GIS education. These include increasing software learning costs, higher computational power demand, and the management of fragmented information in the Web 2.0 context. Addressing these challenges while integrating emerging GIS innovations and restructuring GIS knowledge systems is crucial for the evolution of GIS Education 3.0. This study introduces a Visual Programming-based Geospatial Cyberinfrastructure (V-GCI) framework, integrated with the replicable and reproducible (R&R) framework, to enhance GIS function compatibility, learning scalability, and web GIS application interoperability. Through a case study on spatial accessibility using the generalized two-step floating catchment area method (G2SFCA), this paper demonstrates how V-GCI can reshape the GIS knowledge tree and its potential to enhance replicability and reproducibility within open-source GIS Education 3.0
A Molecular Dynamics Modeling Framework for Shape Memory Vitrimers
No full textVitrimers with self-healing, recycling, and remolding capabilities are changing the paradigm for thermoset polymer design. In the past several years, vitrimers that exhibit shape memory effects and are curable by ultraviolet (UV) light have made significant progress in the realm of 4D printing. Herein, we report a molecular dynamics (MD) modeling framework to model UV curable shape memory vitrimers. We used our framework and compared our modeling results with one UV curable shape memory vitrimer found in the literature, bisphenol A glycerolate dimethacrylate. The comparison showed reasonable agreement between the modeling and experimental results in terms of thermomechanical and shape memory properties, along with self-healing efficiency. It was found that during recycling, it was important for the network to percolate through a majority of the system to get reasonably high recovery stress and recycling efficiency. Once this was achieved, a topological descriptor that was found to represent the compactness of the network was identified as having a very high correlation with recovery stress and recycling efficiency for networks that percolated 70% or more of the monomers in a system
Does increasing absolute conditioned reinforcement rate improve sensitivity to relative conditioned reinforcement rate?
No full textPrevious research has demonstrated several procedural modifications that improve the sensitivity of human behavior to relative rates of conditioned reinforcement or S+ production. Denser rates of reinforcement have proved useful in related human operant research, but the influence of denser rates of S+ production has yet to be evaluated. The purpose of the current study was to evaluate how the absolute S+ production rate influenced sensitivity to relative S+ production rate. Thirty undergraduate students were randomly assigned to three groups for which the absolute rate of S+ production varied but the programmed relative rate of S+ production was held constant across groups. Results similar to those of previous research were obtained with many participants; however, the absolute rate of S+ production exerted no systematic effect on sensitivity or the quality of fits of the generalized matching equation. Exploratory analyses suggest that methods ensuring steady-state responding and improving the predictive value of S+ are important directions for future research
Simulations of Molecular Strong-Field Ionization: Two-Color Orientation-Dependent Yields and Second Ionization as a Probe of Attosecond Charge Migration
No full textIn this dissertation we present computer simulations of two related processes: molecules undergoing strong-field tunneling ionization (SFI) due to an intense external laser fields, and SFI-induced charge migration (CM), which is the coherent movement of positive electron-hole along a molecule, following ionization. We investigate the angle-dependent ionization of oriented polar molecules and demonstrate SFI as a probing technique of CM using bromoacetylene molecule as a test case via second ionization. In the first part of the dissertation, we present orientation-dependent two-color ionization of NO, OCS, and CH3Br using real-time time-dependent density functional theory (RT-TDDFT) with auxiliary basis functions, a tuned range-separated hybrid functional, and a complex absorbing potential (CAP). The highest ionization yields are obtained at θ = 50o for NO and θ = 120o for both OCS and CH3Br, where θ is the angle between the permanent molecular dipole moment and the positive field direction. In these molecules, the ionization yield is maximum when the force on the electrons points from O→N, O→S, and C→Br. In NO, the butterfly-shaped peaks clearly resemble the highest occupied molecular orbital (HOMO), whereas OCS and CH3Br exhibits a more multichannel character to the ionization. These results were also used to validate weak-field asymptotic theory (WFAT) calculations.
In the second part of this dissertation, we use RT-TDDFT with a CAP to simulate how strong-field ionization can be used to probe CM in bromoacetylene (HCCBr). The CM is initiated using a constrained density functional theory (cDFT) sudden approximation for the first ionization, and the second ionization is caused by a single-color (CM frequency matched) laser pulse polarized perpendicular to the CM direction. We filter the initial density matrix to remove spurious high energy excitations caused by cDFT. We observe yield modulations as a function of time-delay between the first and second ionization that correlate with the location of the hole in the molecule. Specifically, ionization increases when the hole is on the triple bond (extra electrons on the bromine atom). These results suggest that SFI may be a viable approach for measuring attosecond CM
SOCIAL STORIES TO SHAPE IMPULSIVE BEHAVIORS TO INCREASE SELF-REGULATION IN PRESCHOOLERS
Get PDFABSTRACT
BACKGROUND: Students need to be able to self-regulate their behavior within the classroom, thus not interrupting instruction and keeping the classroom running smoothly. Self-regulation is a critical skill children need to succeed in multiple aspects of life. Poor self-regulation skills can lead to challenges academically as well as socially. Contrary to self-regulation is impulsivity, which surrounds not thinking before doing. Impulsivity is a common factor seen within the preschool setting, which surrounds multiple behavior variations deemed unsuitable for classroom learning. Previous research indicates that social stories can be implemented within the classroom to decrease inappropriate behaviors in preschoolers with autism (Khantreejitranon, 2018). OBJECTIVE: Social stories are utilized to model appropriate behaviors and expectations. This current study aimed to reflect the approaches taken in the previous research study and encompass the goal of teaching preschoolers in a general education classroom to self-regulate their behavior through social stories and decrease impulsivity. METHODS: Using a multi-baseline design that involved preschool-aged learners, this study sought to determine the impact of social stories on increasing self-regulation skills. The study consisted of interval recording in 15-second intervals, a data collection method where the observer records the participant\u27s behavior at regular 15-second intervals for a total of 15-minute observation sessions. The data points collected through observations measured the relationship between the intervention and the target behavior. RESULTS: The study showed increased self-regulation skills across all participants when implementing the social story intervention. CONCLUSIONS: These findings underscore the impact of social stories on decreasing impulsivity and increasing self-regulation across preschoolers, thus encouraging positive behaviors for young learners within the classroom