Fluorine effect in nucleophilic fluorination at C4 of 1,6-anhydro-2,3-dideoxy-2,3-difluoro-ß-D-hexopyranose.

In this work, we have developed a simple synthetic approach using Et3N·3HF as an alternative to the DAST reagent. We controlled the stereochemistry of the nucleophilic fluorination at C4 of 1,6-anhydro-2,3-dideoxy-2,3-difluoro-4-O-triflate-ß-ᴅ-talopyranose using Et3N·3HF or in situ generated Et3N·1HF. The influence of the fluorine atom at C2 on reactivity at C4 could contribute to a new fluorine effect in nucleophilic substitution. Finally, with the continuous objective of synthesizing novel multi-vicinal fluorosugars, we prepared one difluorinated and one trifluorinated alditol analogue.

Effectiveness and Cost of Implementing Evidence-Based Interventions to Increase Colorectal Cancer Screening Among an Underserved Population in Chicago.

With funding from the Centers for Disease Control and Prevention's Colorectal Cancer Control Program, The University of Chicago Center for Asian Health Equity partnered with a federally qualified health center (FQHC) to implement multiple evidence-based interventions (EBIs) in order to improve colorectal cancer (CRC) screening uptake. The purpose of this study is to determine the effectiveness and cost of implementing a provider reminder system entered manually and supplemented with patient reminders and provider assessment and feedback. The FQHC collected demographic characteristics of the FQHC and outcome data from January 2015 through December 2015 (preimplementation period) and cost from January 2016 through September 2017 (implementation period). Cost data were collected for the implementation period. We report on the demographics of the eligible population, CRC screening order, completion rates by sociodemographic characteristics, and, overall, the effectiveness and cost of implementation. From the preimplementation phase to the implementation phase, there was a 21.2 percentage point increase in CRC screens completed. The total cost of implementing EBIs was $40908.97. We estimated that an additional 283 screens were completed because of the interventions, and the implementation cost of the interventions was $144.65 per additional screen. With the interventions, CRC screening uptake in Chicago increased for all race/ethnicity and demographic backgrounds at the FQHC, particularly for patients aged 50 to 64 years and for Asian, Hispanic, and uninsured patients.

Richardson-Gaudin mean-field for strong correlation in quantum chemistry.

Ground state eigenvectors of the reduced Bardeen-Cooper-Schrieffer Hamiltonian are employed as a wavefunction Ansatz to model strong electron correlation in quantum chemistry. This wavefunction is a product of weakly interacting pairs of electrons. While other geminal wavefunctions may only be employed in a projected Schrödinger equation, the present approach may be solved variationally with polynomial cost. The resulting wavefunctions are used to compute expectation values of Coulomb Hamiltonians, and we present results for atoms and dissociation curves that are in agreement with doubly occupied configuration interaction data. The present approach will serve as the starting point for a many-body theory of pairs, much as Hartree-Fock is the starting point for weakly correlated electrons.