Context Preventing the development of disability in activities of daily living is an important goal in older adults, yet relatively little is known about the disabling process. Objectives To evaluate the relationship between 2 types of intervening events (hospitalization and restricted activity) and the development of disability and to determine whether this relationship is modified by the presence of physical frailty. Design, Setting, and Participants Prospective cohort study, conducted in the general community in greater New Haven, Conn, from March 1998 to March 2003, of 754 persons aged 70 years or older, who were not disabled (ie, required no personal assistance) in 4 essential activities of daily living: bathing, dressing, walking inside the house, and transferring from a chair. Participants were categorized into 2 groups according to the presence of physical frailty (defined on the basis of slow gait speed) and were followed up with monthly telephone interviews for up to 5 years to ascertain exposure to intervening events and determine the occurrence of disability. Main Outcome Measure Disability, defined as the need for personal assistance in bathing, dressing, walking inside the house, or transferring from a chair. Results During the 5-year follow-up period, disability developed among 417 (55.3%) participants, 372 (49.3%) were hospitalized and 600 (79.6%) had at least 1 episode of restricted activity. The multivariable hazard ratios for the development of disability were 61.8 (95% confidence interval [CI], 49.0-78.0) within a month of hospitalization and 5.54 (95% CI, 4.27-7.19) within a month of restricted activity. Strong associations were observed for participants who were physically frail and those who were not physically frail. Hospital admissions for falls were most likely to lead to disability. Intervening events occurring more than a month prior to disability onset were not associated with the development of disability. The populationattributable fractions associated with new exposure to hospitalization and restricted activity, respectively, were 0.48 and 0.19; 0.40 and 0.20, respectively, for frail participants and 0.61 and 0.16, respectively, for nonfrail participants. Conclusions Illnesses and injuries leading to either hospitalization or restricted activity represent important sources of disability for older persons living in the community, regardless of the presence of physical frailty. These intervening events may be suitable targets for the prevention of disability.

Predicting protein–ligand binding affinities and the associated thermodynamics of biomolecular recognition is a primary objective of structure-based drug design. Alchemical free energy simulations offer a highly accurate and computationally efficient route to achieving this goal. While the AMBER molecular dynamics package has successfully been used for alchemical free energy simulations in academic research groups for decades, widespread impact in industrial drug discovery settings has been minimal because of the previous limitations within the AMBER alchemical code, coupled with challenges in system setup and postprocessing workflows. Through a close academia-industry collaboration we have addressed many of the previous limitations with an aim to improve accuracy, efficiency, and robustness of alchemical binding free energy simulations in industrial drug discovery applications. Here, we highlight some of the recent advances in AMBER20 with a focus on alchemical binding free energy (BFE) calculations, which are less computationally intensive than alternative binding free energy methods where full binding/unbinding paths are explored. In addition to scientific and technical advances in AMBER20, we also describe the essential practical aspects associated with running relative alchemical BFE calculations, along with recommendations for best practices, highlighting the importance not only of the alchemical simulation code but also the auxiliary functionalities and expertise required to obtain accurate and reliable results. This work is intended to provide a contemporary overview of the scientific, technical, and practical issues associated with running relative BFE simulations in AMBER20, with a focus on real-world drug discovery applications.

Functional dependence is an age-related condition leading to poor quality of life, if :^--increased health-related care costs, and increased mortality.

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Mobility disability in older persons is a highly dynamic process, characterized by frequent transitions between states of independence and disability. Programs designed to enhance independent mobility should focus not only on the prevention of mobility disability but also on the restoration and maintenance of independent mobility in older persons who become disabled.