4 research outputs found
Expanding the Alternating Propagation–Chain Transfer-Based Polymerization Toolkit: The Iodo–Ene Reaction
Analogous to the thiol–ene
and phosphane–ene polymerizations,
radical-mediated iodo–ene reactions are described here that
proceed via alternating propagation and chain transfer (i.e., APT)
reactions between perfluoroiodide- and vinyl-bearing monomers. The
thermal polymerization of a diiodo/tetraene formulation yielded a
cross-linked, homogeneous polymer that was approximately seven times
as radiopaque as aluminum owing to its high iodine content. Visible-light
photopolymerizations of model iodo–ene monomers were monitored
using mid-IR spectroscopy, revealing that the perfluoroiodide functional
group consumption exceeded that of the vinyl, a discrepancy that decreased
with increasing irradiation intensities and hence polymerization rates.
The functional group conversions in resin formulations with a large
initial perfluoroiodide excess exacerbated secondary side reactions
that led to off-stoichiometric functional group consumption; nevertheless,
photopolymerization of resin formulations with excess vinyl stoichiometry
proceeded according to the ideal APT mechanism
Public health in the Canadian Arctic: Contributions from International Polar Year research
The contributions of several IPY health projects are highlighted in the context of population health indicators for Inuit Nunangat. Food and housing are two critical social determinants of health contributing to health issues on many levels. The nutritional deficit associated with food insecurity and the transition away from traditional and towards market foods represents a dual risk with profound consequences. Knowledge of the physiological benefits associated with traditional food consumption is increasing, including for mental health and chronic disease. Ensuring the safety of traditional foods in terms of zoonotic diseases is thus highly valuable and efforts to institute adequate monitoring and address knowledge gaps are underway. Acute respiratory disease among the young remains a significant public health issue with potential long term effects. The human papilloma virus is manifesting itself among women across northern Canada with high risk types that are more similar to profiles observed in Europe than in North America with possible implications for immunization programs. Despite a high prevalence of Hepatitis B virus infections among residents of Inuit Nunangat, the outcomes appear to be relatively beni