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Glycols as novel solvents for synthesis of squaraine dyes
No full textGlycols are non-volatile, non-flammable solvents for efficient, facile, and environmentally benign syntheses of various types of symmetric and non-symmetric squaraine dyes, thus providing a viable alternative to conventionally used n-butanol/toluene system
Community-based clean-up schemes in urban parks can improve water sources for bats
No full textBats are essential to ecosystems, providing services like pollination, seed dispersal, and pest control, yet their populations are declining globally due to human-driven habitat loss. To counter these effects, conservationists promote strategies like enhancing habitats, even in urban areas. Yet to support healthy bat communities, they need to offer suitable resources such as water. Water access for bats depends on both availability and accessibility. Accessibility is often limited by "clutter"--physical obstructions such as vegetation, rocks, or debris that restrict bats ability to drink in flight. Urban litter, primarily non-biodegradable items, degrades aquatic habitats, potentially restricting access for wildlife. Targeted litter removal, therefore, has the potential to reduce habitat degradation and improve access for species like bats. To investigate this, we implemented a community-based cleanup at select water sources in Fort Worth, Texas, from 2021 to 2024, recording bat activity with thermal and acoustic tools before and after cleanup to assess the impact of litter removal on bat drinking activity.
Post-clean up, overall bat presence increased significantly at both sites, with drinking activity increasing for hoary bats (Lasiurus cinereus), silver-haired bats (Lasionycteris noctivagans), and Mexican free-tailed bats (Tadarida brasiliensis), These findings reveal that litter does act as clutter, thereby limiting access to water for certain bat species with open-space flight patterns. Overall, our results highlight the value of litter-free water sources in urban environments for promoting bat species diversity and resource use. By demonstrating the positive impact of community clean-ups on bat activity, this project underscores the role of citizen-led conservation initiatives in fostering urban biodiversity, improving ecosystem health, and supporting local conservation strategies
The impact of State of Surrender on the relationship between engagement in substance use treatment and meaning in life presence: a pilot study
No full textThe current study examined the construct of State of Surrender (SoS)�defined as a willingness to accept, without resistance, what is to come�and investigated SoS as a statistical mediator of the relationship between engagement in substance use treatment and meaning in life (MIL). Using a cross-sectional design, participants were 123 people involved with the legal system participating in a 6-month residential treatment program for substance use. Results showed that measures of treatment engagement, including treatment participation, counselor rapport, and peer support, were all positively associated with SoS scores (R2s???21.16). Moreover, while controlling for time spent in treatment, SoS statistically mediated the positive association between aspects of treatment engagement and MIL. State of Surrender may be a targetable process in substance use treatment that aids in recovery by orienting clients toward what they find meaningful in life. Future directions and practical considerations are discussed
Short peptides based on the conserved regions of MIEN1 protein exhibit anticancer activity by targeting the MIEN1 signaling pathway
No full textMigration and invasion enhancer 1 (MIEN1) overexpression characterizes several cancers and facilitates cancer cell migration and invasion. Leveraging conserved immunoreceptor tyrosine-based activation motif and prenylation motifs within MIEN1, we identified potent anticancer peptides. Among them, bioactive peptides LA3IK and RP-7 induced pronounced transcriptomic and protein expression changes at sub-IC50 concentrations. The peptides effectively inhibited genes and proteins driving cancer cell migration, invasion, and epithelial-mesenchymal transition pathways, concurrently suppressing epidermal growth factor-induced nuclear factor kappa B nuclear translocation in metastatic breast cancer cells. Specifically, peptides targeted the same signal transduction pathway initiated by MIEN1. Molecular docking and CD spectra indicated the formation of MIEN1-peptide complexes. The third-positioned isoleucine in LA3IK and CVIL motif in RP-7 were crucial for inhibiting breast cancer cell migration. This is evident from the limited migration inhibition observed when MDA-MB-231 cells were treated with scrambled peptides LA3IK SCR and RP-7 SCR. Additionally, LA3IK and RP-7 effectively suppressed tumor growth in an orthotopic breast cancer model. Notably, mice tolerated high intraperitoneal (ip) peptide doses of 90 mg/Kg well, surpassing significantly lower doses of 5 mg/Kg intravenously (iv) and 30 mg/Kg intraperitoneally (ip) used in both in vivo pharmacokinetic studies and orthotopic mouse model assays. D-isomers of LA3IK and RP-7 showed enhanced anticancer activity compared to their L-isomers. D-LA3IK remained stable in mouse plasma for 24 h with 75% remaining, exhibiting superior pharmacokinetic properties over D/L-RP-7. In summary, our findings mark the first report of short peptides based on MIEN1 protein sequence capable of inhibiting cancer signaling pathways, effectively impeding cancer progression both in vitro and in vivo
The Making of LiterAce: Combating Real-World Communication Problems by Building and Sustaining a Brand through Advertising and Public Relations Techniques
No full textThis project details the development and sustainment of an anti-misinformation brand using a combination of classic and revolutionary advertising and public relations tactics. The brand, LiterAce, uses a form of artificial intelligence (AI) known as natural language processing (NLP) to calculate the reliability of media sources and prevent internet users from spreading misinformation. Several key campaigns have been designed for this brand's launch; some are designed to handle an array of controversies that could potentially arise from LiterAce's launch, while others are purely intended to build and maintain positive brand awareness both before and after the brand launches
Synthetic Approaches Toward Phosphorus-Containing BODIPY and Squaraine Dyes: Enhancing Versatility of Small-Molecule Fluorophores
No full textPhosphorus-containing fluorophores provide a versatile framework for tailoring photophysical properties, enabling the design of advanced fluorogenic materials for various applications. Boron dipyrromethene (BODIPY) and squaraine dyes are of interest due to their multifaceted modularity and synthetic accessibility. Incorporating phosphorus-based functional groups into BODIPY or squaraine scaffolds has been achieved through a plethora of synthetic methods, including post-dye assembly functionalization. These modifications often influence key spectroscopic properties and molecular functionality by expanding their utility in bioimaging, sensing, photosensitization, and theranostic applications. By leveraging the tunable nature of phosphorus-containing moieties, these dyes hold immense promise for addressing current challenges in spectroscopy, imaging, and material designs while unlocking new opportunities for advanced functional systems in chemistry, biology, and medicine
Förster Resonance Energy Transfer and Enhanced Emission in Cs4PbBr6 Nanocrystals Encapsulated in Silicon Nano-Sheets for Perovskite Light Emitting Diode Applications
No full textEncapsulating Cs4PbBr6 quantum dots in silicon nano-sheets not only stabilizes the halide perovskite, but also takes advantage of the nano-sheet for a compatible integration with the traditional silicon semiconductor. Here, we report the preparation of un-passivated Cs4PbBr6 ellipsoidal nanocrystals and pseudo-spherical quantum dots in silicon nano-sheets and their enhanced photoluminescence (PL). For a sample with low concentrations of quantum dots in silicon nano-sheets, the emission from Cs4PbBr6 pseudo-spherical quantum dots is quenched and is dominated with Pb2+ ion/silicene emission, which is very stable during the whole measurement period. For a high concentration of Cs4PbBr6 ellipsoidal nanocrystals in silicon nano-sheets, we have observed F�rster resonance energy transfer with up to 87% efficiency through the oscillation of two PL peaks when UV excitation switches between on and off, using recorded video and PL lifetime measurements. In an area of a non-uniform sample containing both ellipsoidal nanocrystals and pseudo-spherical quantum dots, where Pb2+ ion/silicene emissions, broadband emissions from quantum dots, and bandgap edge emissions (515 nm) appear, the 515 nm peak intensity increases five times over 30 min of UV excitation, probably due to a photon recycling effect. This irradiated sample has been stable for one year of ambient storage. Cs4PbBr6 quantum dots encapsulated in silicon nano-sheets can lead to applications of halide perovskite light emitting diodes (PeLEDs) and integration with traditional semiconductor materials
Helping hampered bidders—Do subsidy auctions work as intended?
No full textThe use of preference or discriminatory auctions, where one class of bidders is offered favored treatment over another class, has received mixed attention in the literature. Research has shown there is often an economic benefit of such policies in procurement auctions thanks to lower costs for buyers as incentives are offered to disadvantaged sellers. In this paper, we study one type of preferential procurement auction: the subsidy. Using a set of controlled experiments, we compare actual bidder behavior to what is predicted in equilibrium and find consistent (but overly aggressive) patterns overall. By testing a common bid strategy assumption, we also identify a behavioral framing bias that may trap sellers in these suboptimal strategies. Finally, we compare subsidies to another common discriminatory mechanism—the price preference—and find evidence that buyers interested in increasing the welfare of disadvantaged sellers should use subsidies instead of price preference auctions, thanks to a surprising difference in outcomes between preference types. Due to the wide use of bid preference auctions to support both policy and social aims, our findings have both financial and societal implications
Unincorporation in counties as a political determinant of health: An exploration of five states
No full textLocal government policies and practices shape the context of the places that can alter a population's life chances through socioeconomic factors, built environments, and healthcare access. County governments, one of the most ubiquitous U.S. political structures, impact health outcomes within their jurisdiction through multiple policy levers and pathways. By identifying which political determinants within counties are associated with variation in life expectancy and premature death, we can better intervene on modifiable factors. One overlooked political determinant from public health studies is the county's responsibility as the primary local government for approximately a third of the U.S. population and 93% of land in unincorporated areas. To conduct an ecological study and assess associations between county population health and county responsibility for unincorporated areas and populations, we created and tested two county indicators of unincorporation. Multilevel multivariable regression results showed that larger proportions of unincorporated land within a county are associated with lower average county life expectancy. More testing of the measurement is needed to understand the relationship between unincorporation, county government, and population health outcomes
THE RELATIONSHIP BETWEEN THE INVERTED YIELD CURVE AND RECESSION PROBABILITIES
No full textThis study investigates whether the underlying factors of the yield curve, investor confidence (CBOE), consumer confidence (CSI), and money supply (M2), serve as key predictors of recession probabilities, and whether incorporating these factors enhances predictive accuracy compared to the yield spread alone. Using logistic regression models, the research evaluates these variables across three cases: no time lag, a 3-month lag, and a 6-month lag. The findings reveal that all four factors are significant predictors of recession probabilities, with their impacts varying by timing. Future research could refine this framework by optimizing time lags for individual variables, further enhancing its accuracy in predicting economic downturns