Catechol on TiO 2 is a model system for a class of molecules that bind and interact very strongly with metal oxides. This interaction gives rise to a marked charge-transfer absorption band that can be used to sensitize the complex to visible light. In solar cells, these are called type II sensitizers in contrast with type I sensitizers where an excitation of the molecule with subsequent charge injection is the main mechanism for placing an electron in the conduction band of the semiconductor. The adsorption geometry of these molecules is critical in their functioning. Nuclear magnetic resonance (NMR) spectroscopic methods can be used to elucidate structural information about the local geometry at the substrate−molecule interface. NMR methods coupled with density functional theory (DFT) allow for the detailed characterization of molecular binding modes. In the present work, we report a solid-state NMR and DFT study of catechol on TiO 2 . DFT-GIPAW chemical shift predictions for the 13 C CP-MAS experiments unambiguously indicate the presence of a chelated geometry. 1 H → 13 C cross-polarization build-up kinetics were used to determine the protonation state of additional geometries and point toward the presence of molecular species. The most stable adsorption modes on regular slab models were found to be bidentate, and it is only in the presence of defective surfaces where the chelated mode is stabilized in the presence of undercoordinated titanium surface sites. The combined NMR and DFT approach thus allows characterization of the binding geometry, which is a stepping stone in the design of more complex light-harvesting architectures. This work constitutes, to the best of our knowledge, the first detailed instance of combined solid-state NMR and DFT studies on this class of materials.

Many FDA-approved anti-cancer therapies, targeted toward a wide array of molecular targets and signaling networks, have been demonstrated to activate the unfolded protein response (UPR). Despite a critical role for UPR signaling in the apoptotic execution of cancer cells by many of these compounds, the authors are currently unaware of any instance whereby a cancer drug was developed with the UPR as the intended target. With the essential role of the UPR as a driving force in the genesis and maintenance of the malignant phenotype, a great number of pre-clinical studies have surged into the medical literature describing the ability of dozens of compounds to induce UPR signaling in a myriad of cancer models. The focus of the current work is to review the literature and explore the role of the UPR as a mediator of chemotherapy-induced cell death in squamous cell Carcinomas of the head and neck (HNSCC) and oral cavity (OCSCC), with an emphasis on preclinical studies.

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Objective: To evaluate the cost-effectiveness of open versus endoscopic surgical repair of Zenker’s diverticulum. Methods: In this study, an economic decision tree was utilized to compare the cost-effectiveness of open surgery compared to endoscopic surgery. The primary outcome in this analysis was the incremental cost-effectiveness ratio (ICER) that was calculated based on the economic decision tree. The probability of post-operative esophageal perforation complications, revision rates, and effectiveness of each procedure along with associated costs were extracted to construct the decision tree. Univariate sensitivity analysis was then utilized to determine how changes in esophageal perforation rate affect the cost-effectiveness of each surgical approach. Results: The ICER of open surgery for Zenker’s diverticulum was $67 877, above most acceptable willingness to pay (WTP) thresholds. Additionally, if the probability of esophageal perforation with endoscopic surgery is above 5%, then open surgery becomes a more cost-effective option. Probabilistic sensitivity analysis using Monte Carlo simulations also showed that at the WTP thresholds of $30 000 and $50 000, endoscopic surgery is the most cost-effective method with 83.9% and 67.6% certainty, respectively. Conclusion: Open surgery and endoscopic surgery are 2 treatment strategies for Zenker’s diverticulum that each have their own advantages and disadvantages that can complicate the decision-making process. With no previous cost-effectiveness analysis of open versus endoscopic surgery for Zenker’s diverticulum, our results support the endoscopic approach at most common WTP thresholds. Particularly with the current focus on rising healthcare costs, our results can serve as an important adjunct to medical decision-making for patients undergoing treatment for Zenker’s diverticulum.