Investigation Of New Ligand Architechtures Towards Proton And Water Reduction Catalysis By Cobalt Complexes

We designed several redox-active ligand architectures to optimize and understand the redox, electronic, and catalytic properties of their respective cobalt complexes. Ligand design was varied from pentadentate donor phenolate to tetradentate acceptor oxime in order to reduce the overpotential of hydrogen generation in organic solvents. We altered the substitution, axial ligands and axial ligand substitutions to vary electronic and catalytic properties for such tetra- or pentadentate ligand systems. Knowledge of the nature of the active species for catalysis enabled us to design the pentadentate oxime ligand which exhibited rich reaction chemistry along with suitable catalytic property in organic solvent. Presence of several polar groups like -OH and -NH and the absence of any aromatic rings make this complex water soluble which is an added advantage. Additionally, this complex exhibited excellent catalytic properties in water with low onset overpotential and high turnover number. We developed similar redox-active π-acceptor pentadentate phenylene-bridged pyridine-rich ligand which provided extremely versatile reaction chemistry after complexation with cobalt. These complexes displayed catalytic properties at moderate to low-overpotential in acetonitrile with good turnover numbers. Furthermore, the water solubility and tunability of such complexes make them suitable candidates for water reduction. Therefore, water reduction was carried out with these complexes showing low onset overpotentials and high turnover numbers. Finally, we incorporated [Ru(bpy)2]2+-based photosensitized with one of the catalytic module (cobalt tetradentate oxime) to generate heterobimetallic [RuIICoIII] species which displayed quenching of CoIII upon electron transfer from RuII* excited state

The role of prospect theory in screening behavior decision-making in a health-insured population of South Africa

Background: Prospect theory suggests that people avoid risks when faced with the benefits of a decision but take risks when faced with the costs of a decision. Screening for diseases can be defined as a ‘risk’, in the context of uncertainty. The outcome can either be a ‘benefit’ of good health or a ‘cost’ of ill health or poor-quality health. Purpose: To assess whether prospect theory can predict screening behavior in the context of a chronic disease diagnosis as well as the exposure to incentives to screen. Methods: A retrospective longitudinal case-control study for the period 2008-2011 was conducted using a random 1% sample of 170,471 health-insured members, assessing screening for cancers, chronic diseases of lifestyle and HIV, some of whom voluntarily join an incentivized wellness program. Results: Individuals diagnosed with a chronic disease screened up to 9.0% less for some diseases over time. Mammogram screening however increased (p<0.001). Where a family member was diagnosed with a chronic disease, individual screening decreased up to 8.6%. Similarly females in families where a member was diagnosed with a chronic disease screened more for breast cancer (p<0.001). Males were more sensitive to incentives only for HIV screening (p<0.001), while the female responses to incentives were inconsistent. Conclusion: A chronic disease diagnosis or the risk of developing a chronic disease resulted in reduced future screening behavior for most diseases. The role of incentives was inconsistent. Prospect theory adequately predicts screening behavior when diagnosed or faced with a possible chronic disease diagnosis for most screening tests except for females screening for breast cancer

Predictors of adherence to screening guidelines for chronic diseases of lifestyle, cancers, and HIV in a health-insured population in South Africa

Background: Adherence to screening guidelines has been widely accepted to reduce morbidity, mortality, and cost outcomes. The aim of this study was to identify predictors of adherence to screening guidelines for chronic diseases of lifestyle (CDL), cancers, and HIV in a health-insured population in South Africa, some of whom voluntarily opt into a wellness program that incentivizes screening. Method: A cross-sectional study for the period 2007-2011 was conducted using a random sample of 170,471 health insurance members from a single insurer. Adherence to screening guidelines was calculated from medical claims data. Results: Adherence to screening guidelines ranged from 1.1% for colorectal cancer to 40.9% for cholesterol screening. Members of the wellness program were up to three times more likely to screen for diseases (odds ratio [OR]=3.2 for HIV screening, confidence interval [CI]=2.753.73). Plan type (full comprehensive plan) was most strongly associated with cholesterol screening (OR=3.53, CI=3.273.80), and most negatively associated (hospital-only core plan) with cervical cancer screening (OR=0.44, CI=0.280.70). Gender was a negative predictor for glucose screening (OR=0.88, CI=0.820.96). Provincial residence was most strongly associated with cervical cancer screening (OR=1.89, CI=0.655.54). Conclusion: Adherence to screening recommendations was <50%. Plan type, gender, provincial residence, and belonging to an incentivized wellness program were associated with disproportionate utilization of screening services, even with equal payment access

PHC re-engineering may relieve overburdened tertiary hospitals in South Africa

Under the National Health Insurance, a hospital is expected to provide service to patients based on its category. However, in reality the tertiary hospitals offer every level of care, resulting in poor quality of care and over-expenditure. The Polokwane/Mankweng Hospital Complex is a provincial tertiary hospital that delivers tertiary care as well as dealing with some secondary and primary care cases. This study evaluated the hospital casualty department in the Polokwane/Mankweng Hospital Complex. A sample of 250 patients’ records was selected by simple random sampling from a cohort of 14 113 patients who attended the Polokwane Hospital Casualty Department during the 1-year study period. Most patients were admitted in the casualty department as a result of injuries (25%). Only 20% (N=51) of the patients were referred from other health facilities. Half of the patients could have been managed at a regional or district hospital. The overall expenditure for the casualty unit during the 1-year study period was R10  321 401.42 and the combined unit cost was estimated at R731.34 per single emergency care patient excluding the capital costs. Referral systems must be strengthened to manage patients at regional and district level to reduce the burden on the Polokwane/Mankweng Hospital Complex. It is hoped that the Primary Health Care (PHC) Re-engineering Policy will address this by strengthening the referral system in PHC facilities