Carbonization Studies on Mammut americanum Tusk

Many preservation attempts have been made on the tusk that the University of Northern Iowa acquired. Due to the poor preservation attempts a lot of damage has happened and has caused the tusk to be in a way of disrepair. The Carver grant is very keen on the future preservation of the tusk. The sublimation of nucleobases will be able to help guide the type of preservation methods used in order to preserve the nucleobases and possible DNA still in the tusk. The extraction of nucleobases will not only help with the future preservation of tusk but it will also help to provide a potential family tree of the Mammut americanum founded in the area.https://scholarworks.uni.edu/mastodon_posters/1004/thumbnail.jp

Dynamics and Selective Remodeling of the DNA-binding Domains of RPA

Replication protein A (RPA) coordinates important DNA metabolic events by stabilizing single-stranded DNA (ssDNA) intermediates, activating the DNA-damage response and handing off ssDNA to the appropriate downstream players. Six DNA-binding domains (DBDs) in RPA promote high-affinity binding to ssDNA yet also allow RPA displacement by lower affinity proteins. We generated fluorescent versions of Saccharomyces cerevisiae RPA and visualized the conformational dynamics of individual DBDs in the context of the full-length protein. We show that both DBD-A and DBD-D rapidly bind to and dissociate from ssDNA while RPA remains bound to ssDNA. The recombination mediator protein Rad52 selectively modulates the dynamics of DBD-D. These findings reveal how RPA-interacting proteins with lower ssDNA binding affinities can access the occluded ssDNA and remodel individual DBDs to replace RPA

Investigating Reactive Diruthenium Intermediates for C-H Bond Silylation Reactions

Diruthenium complexes have been shown to effectively catalyze the cleavage of carbon-hydrogen bonds in benzene and pyridine to form carbon-silicon bonds. However, the catalytic cycle of these diruthenium complexes is still unknown. Two stable dimethyl diruthenium complexes were synthesized using CH3MgBr and CH3I with yields between 57-68% and protonated with Brookhart\u27s acid and triflic acid. Protonation of the dimethyl diruthenium complexes resulted in promising reactive monomethyl diruthenium complexes, which have been tested as possible intermediates in the catalytic cycle

Halloween House

Since 2007, the Student Affiliates of the American Chemical Society at the University of Northern Iowa has organized a community outreach program called Halloween House. What started out as a one-room chemistry demonstration show 12 years ago, has now evolved into a huge event in collaboration with other STEM clubs on campus. The event brought in between 1000-1200 community members, mainly elementary aged-students, last fall. The collaboration amongst different STEM clubs in physics, biology, earth science, and chemistry allows students to have an interdisciplinary experience, exploring all of the sciences and seeing how they all connect. The Halloween House activities engage students with hands on activities and demonstration shows with captivating storylines that connect all of the demonstrations. Every room in the Halloween House event has a theme, for example, demonstrations involving fire are performed in the ‘Devil’s Den’ room. Approximately 35 college students partake in performing the chemistry demonstrations. Performing shows like these requires safety awareness and good communication skills on the part of the demonstrators. This is good practice for both future chemists and educators. For the audience, the demonstrations serve as an educational lesson in topics such as acid/base chemistry (rainbow connection), combustion and other exothermic reactions (lycopodium flame thrower), and intrinsic properties of different elements (flame test). After watching a demonstration, kids are asked to think critically about what they observed. After a couple of volunteers, the correct scientific explanation is given, completing the educational experience

Dermatologist-like explainable AI enhances trust and confidence in diagnosing melanoma

Abstract Artificial intelligence (AI) systems have been shown to help dermatologists diagnose melanoma more accurately, however they lack transparency, hindering user acceptance. Explainable AI (XAI) methods can help to increase transparency, yet often lack precise, domain-specific explanations. Moreover, the impact of XAI methods on dermatologists’ decisions has not yet been evaluated. Building upon previous research, we introduce an XAI system that provides precise and domain-specific explanations alongside its differential diagnoses of melanomas and nevi. Through a three-phase study, we assess its impact on dermatologists’ diagnostic accuracy, diagnostic confidence, and trust in the XAI-support. Our results show strong alignment between XAI and dermatologist explanations. We also show that dermatologists’ confidence in their diagnoses, and their trust in the support system significantly increase with XAI compared to conventional AI. This study highlights dermatologists’ willingness to adopt such XAI systems, promoting future use in the clinic