The role of tunneling in enzyme catalysis of C–H activation

AbstractRecent data from studies of enzyme catalyzed hydrogen transfer reactions implicate a new theoretical context in which to understand C–H activation. This is much closer to the Marcus theory of electron transfer, in that environmental factors influence the probability of effective wave function overlap from donor to acceptor atoms. The larger size of hydrogen and the availability of three isotopes (H, D and T) introduce a dimension to the kinetic analysis that is not available for electron transfer. This concerns the role of gating between donor and acceptor atoms, in particular whether the system in question is able to tune distance between reactants to achieve maximal tunneling efficiency. Analysis of enzyme systems is providing increasing evidence of a role for active site residues in optimizing the inter-nuclear distance for nuclear tunneling. The ease with which this optimization can be perturbed, through site-specific mutagenesis or an alteration in reaction conditions, is also readily apparent from an analysis of the changes in the temperature dependence of hydrogen isotope effects

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Mapping psychological, organizational, and technological factors that play a rol in the adoption and optimal use of Electronic Health Records (EHRs) for end users in hospitals: A Scoping Review

Countries across the world have introduced EHRs (Electronic Health Records). EHRs have been linked to public health benefits, including increased information exchange between healthcare providers, improved medical decision-making, better chronic disease management, and risk group identification. Optimal EHR use has the potential to reduce costs, increase security and quality of care, and enhance EHR system trustworthiness, thus contributing to sustainable, resilient healthcare. However, problems regarding EHR acceptance and use among healthcare professionals are frequently reported. As EHRs develop fast, optimal EHR use requires resilience from healthcare organizations and professionals: continuous learning and adaptation to system changes and new functionalities. Due to the current corona crisis, EHRs may progress even faster because of the need to provide more efficient distance healthcare, track COVID-19 spreading, and gather information on this new coronavirus. Challenges surrounding technological healthcare innovations involve a complex interplay between professionals, organizations, and technologies, a thorough understanding of critical success factors for optimal EHR use requires a multidisciplinary approach. On the individual level, Smart EHR Use is likely affected by both ability and motivation. Psychology literature suggests that technological self-efficacy, one’s confidence in one’s ability to use a technology, may be a key factor in technology acceptance and use. Furthermore, a sense of autonomy, competence, and relatedness are essential for intrinsic motivation (Self-Determination Theory). EHRs may erode these basic psychological needs (e.g. when physicians feel that EHRs ‘tell them what to do’), but may also satisfy these needs (e.g. when physicians feel that EHRs improve their skills/care). This may affect the motivation to use EHRs smartly. While system design partly affects such user experiences, individual differences (e.g. computer literacy) and implementation practices likely play an important role, too. Despite their relevance for understanding Smart EHR Use, self-efficacy and self-determination have received limited attention in previous EHR use literature. Healthcare professionals’ self-efficacy and self-determination can be influenced by HR practices and structural organizational factors. Important HR practices that stimulate positive work behaviour (like Smart EHR Use) include involvement and empowerment. Furthermore, implementing new professional behaviour requires management practices focusing on development. Importantly, changing individual and collective work routines is relevant for successful implementation of technological innovations (expansive learning theories). Finally, perceptions regarding the healthcare organization’s capability to anticipate change may affect Smart EHR Use (Dynamic Capabilities Framework). While successful EHR usage is known to be an organization-wide effort, research on EHR use is rarely multidisciplinary. This scoping review will combine insights from psychology, HRM, education, and information sciences to gain a clear insight of which facilitators and barriers play a role in the optimization of EHR use

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least 4 m. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the 6.5 m James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 yr, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit