Assistance provided in daily tasks and difficulty experienced by caregivers for people living with dementia.

INTRODUCTION: There is a growing body of research that addresses caregivers for people living with dementia. However, there is limited research looking at the perceptions of caregivers in specific daily tasks. To address this gap, this study investigated the assistance caregivers provided and the difficulty they faced when completing daily tasks for people with dementia and, additionally, how these experiences might relate to their perceived burden. METHODS: Sixty-two caregivers for people living with dementia completed the study. Data were collected, through a survey, on the level of assistance caregivers provided, and the difficulties they experienced. The Zarit Burden Scale was used to measure the level of perceived burden. Descriptive statistics and Spearman's correlation coefficient were used to report the results and the relationship between the perceived burden, the level of assistance provided, and the difficulty experienced. RESULTS: The activities of daily living that caregivers provided the most assistance for was dressing and showering. Most instrumental activities of daily living required maximal to total assistance. Overall, the caregivers did not experience a high level of difficulty with assisting with these daily tasks in comparison to the level of assistance provided. The caregiver burden was associated significantly with the difficulties experienced in dressing, toileting, and showering (rho = 0.30-0.75), most instrumental activities of daily living (rho = 0.29-0.47), but not with the level of assistance provided. CONCLUSION: Caregivers are assisting in many daily tasks. Their level of difficulty is relatively low in comparison to the level of assistance they provide. Significant correlations were found between the difficulties experienced and the burden scale. There is a need for occupational therapists to address the specific daily tasks and the concerns experienced by caregivers and to provide them with adequate support to improve the quality of care for people with dementia.

Calculating protein-ligand binding affinities with MMPBSA: Method and error analysis.

Molecular Mechanics Poisson-Boltzmann Surface Area (MMPBSA) methods have become widely adopted in estimating protein-ligand binding affinities due to their efficiency and high correlation with experiment. Here different computational alternatives were investigated to assess their impact to the agreement of MMPBSA calculations with experiment. Seven receptor families with both high-quality crystal structures and binding affinities were selected. First the performance of nonpolar solvation models was studied and it was found that the modern approach that separately models hydrophobic and dispersion interactions dramatically reduces RMSD's of computed relative binding affinities. The numerical setup of the Poisson-Boltzmann methods was analyzed next. The data shows that the impact of grid spacing to the quality of MMPBSA calculations is small: the numerical error at the grid spacing of 0.5 Å is already small enough to be negligible. The impact of different atomic radius sets and different molecular surface definitions was further analyzed and weak influences were found on the agreement with experiment. The influence of solute dielectric constant was also analyzed: a higher dielectric constant generally improves the overall agreement with experiment, especially for highly charged binding pockets. The data also showed that the converged simulations caused slight reduction in the agreement with experiment. Finally the direction of estimating absolute binding free energies was briefly explored. Upon correction of the binding-induced rearrangement free energy and the binding entropy lost, the errors in absolute binding affinities were also reduced dramatically when the modern nonpolar solvent model was used, although further developments were apparently necessary to further improve the MMPBSA methods. © 2016 Wiley Periodicals, Inc.