Gelation in Photoinduced ATRP with Tuned Dispersity of the Primary Chains.

We investigated gelation in photoinduced atom transfer radical polymerization (ATRP) as a function of Cu catalyst loading and thus primary chain dispersity. Using parallel polymerizations of methyl acrylate with and without the addition of a divinyl crosslinker (1,6-hexanediol diacrylate), the approximate values of molecular weights and dispersities of the primary chains at incipient gelation were obtained. In accordance with the Flory-Stockmayer theory, experimental gelation occurred at gradually lower conversions when the dispersity of the primary chains increased while maintaining a constant monomer/initiator/crosslinker ratio. Theoretical gel points were then calculated using the measured experimental values of dispersity and initiation efficiency. An empirical modification to the Flory-Stockmayer equation for ATRP was implemented, resulting in more accurate predictions of the gel point. Increasing the dispersity of the primary chains was found not to affect the distance between the theoretical and experimental gel points and hence the extent of intramolecular cyclization. Furthermore, the mechanical properties of the networks, such as equilibrium swelling ratio and shear storage modulus showed little variation with catalyst loading and depended primarily on the crosslinking density.

Self-Assembled, Hierarchical Structured Surfaces for Applications in (Super)hydrophobic Antiviral Coatings.

A versatile method for the creation of multitier hierarchical structured surfaces is reported, which optimizes both antiviral and hydrophobic (easy-clean) properties. The methodology exploits the availability of surface-active chemical groups while also manipulating both the surface micro- and nanostructure to control the way the surface coating interacts with virus particles within a liquid droplet. This methodology has significant advantages over single-tier structured surfaces, including the ability to overcome the droplet-pinning effect and in delivering surfaces with high static contact angles (>130°) and good antiviral efficacy (log kill >2). In addition, the methodology highlights a valuable approach for the creation of mechanically robust, nanostructured surfaces which can be prepared by spray application using nonspecialized equipment.

Examining the prevalence of epilepsy and delivery of epilepsy care in Ireland.

PURPOSE: To examine the prevalence of epilepsy and delivery of epilepsy care in Ireland. METHODS: A multiple case ascertainment methodology was employed examining five nationwide data sources. Data were obtained via (1) a nationwide population-based health survey, (2) secondary data analysis of all reimbursements for prescriptions of antiepilepsy medication nationwide from 2002 to 2005, (3) a nationwide survey of primary care community-based physicians, (4) a nationwide survey of specialist care hospital-based neurologists, and (5) secondary data analysis of inpatient discharges from acute hospitals nationwide for persons with a diagnosis of epilepsy between 2000 and 2005. RESULTS: The findings indicate that nationwide approximately (1) 10 per 1,000 persons (n = 31,000) 18 years and older have self-reported lifetime prevalence of epilepsy, (2) 8.3-9 per 1,000 (approximately 33,000-36,000) persons 5 years and older are being treated for epilepsy using antiepilepsy medication, (3) the typical general practitioner provides care to an average of 13 patients with active epilepsy and epilepsy in remission with treatment, (4) specialist care is provided on a weekly basis to approximately 442 persons with active epilepsy and epilepsy in remission with treatment, and (5) approximately 67 discharges for persons with a primary or secondary diagnosis of epilepsy are reported from acute hospitals weekly. DISCUSSION: This study is distinguished as the first nationwide prevalence study of epilepsy in Europe and provides previously unavailable data on this population in Ireland. Moreover, this study illustrates the merits of secondary data analysis of existing sources when access to clinical sources for the purpose of identifying epidemiologic samples is limited.