Creative destruction in science

Drawing on the concept of a gale of creative destruction in a capitalistic economy, we argue that initiatives to assess the robustness of findings in the organizational literature should aim to simultaneously test competing ideas operating in the same theoretical space. In other words, replication efforts should seek not just to support or question the original findings, but also to replace them with revised, stronger theories with greater explanatory power. Achieving this will typically require adding new measures, conditions, and subject populations to research designs, in order to carry out conceptual tests of multiple theories in addition to directly replicating the original findings. To illustrate the value of the creative destruction approach for theory pruning in organizational scholarship, we describe recent replication initiatives re-examining culture and work morality, working parents\u2019 reasoning about day care options, and gender discrimination in hiring decisions. Significance statement It is becoming increasingly clear that many, if not most, published research findings across scientific fields are not readily replicable when the same method is repeated. Although extremely valuable, failed replications risk leaving a theoretical void\u2014 reducing confidence the original theoretical prediction is true, but not replacing it with positive evidence in favor of an alternative theory. We introduce the creative destruction approach to replication, which combines theory pruning methods from the field of management with emerging best practices from the open science movement, with the aim of making replications as generative as possible. In effect, we advocate for a Replication 2.0 movement in which the goal shifts from checking on the reliability of past findings to actively engaging in competitive theory testing and theory building. Scientific transparency statement The materials, code, and data for this article are posted publicly on the Open Science Framework, with links provided in the article

Restoration choices for endodontically treated posterior teeth

There aren't any generally accepted guidelines for the restoration of an endodontically treated tooth. With a questionnaire among dental general practitioners and endodontists, several restorative treatment options for endodontically treated molars and premolars were identified. The questionnaire inventoried the influence of various parameters on treatment preferences. For each case, additional questions were put about material choice, cuspal coverage and the use of root canal posts. Both groups identified the vertical root fracture as the most common reason for extraction. The dentist general practitioner waited longer than the endodontist to make a permanent restoration in the case of apical periodontitis. Treatment preferences were found to be the same for premolars and molars. In the case of premolars, a root canal post was indicated more often and the location of the wall (bearing/non-bearing) influenced the choice of cuspal coverage. Of the dentist general practitioners and endodontists, 51-53% and 75-94%, respectively, preferred a partial over a full crown preparation in the case of single-walled teeth

Canopy gradients in leaf intercellular CO2 mole fractions revisited: interactions between leaf irradiance and water stress need consideration

Intercellular CO2 mole fractions (Ci) are lower in the upper canopy relative to the lower canopy leaves. This canopy gradient in Ci has been associated with enhanced rates of carbon assimilation at high light, and concomitant greater draw-downs in Ci. However, increases in irradiance in the canopy are generally also associated with decreases in leaf water availability. Thus, stress effects on photosynthesis rates (A) and stomatal conductance (G), may provide a further explanation for the observed Ci gradients. To test the hypotheses of the sources of canopy variation in Ci, and quantitatively assess the influence of within-canopy differences in stomatal regulation on A, the seasonal and diurnal variation in G was studied in relation to seasonal average daily integrated quantum flux density (Qint) in tall shadeintolerant Populus tremula L. trees. Daily time-courses of A were simulated using the photosynthesis model of Farquhar et al. (Planta 149, 78–90, 1980). Stable carbon isotope composition of a leaf carbon fraction with rapid turnover rate was used to estimate canopy gradient in Ci during the simulations. Daily maximum G(Gmax) consistently increased with increasing Qint. However, canopy differences in Gmax decreased as soil water availability became limiting during the season. In water-stressed leaves, there were strong mid-day decreases in G that were poorly associated with vapour pressure deficits between the leaf and atmosphere, and the magnitude of the mid-day decreases in G occasionally interacted with long-term leaf light environment. Simulations indicated that the percentage of carbon lost due to mid-day stomatal closure was of the order of 5–10%, and seasonal water stress increased this percentage up to 20%. The percentage of carbon lost due to stomatal closure increased with increasing Qint. Canopy differences in light environment resulted in a gradient of daily average Ci of approximately 20 m mol mol-1. The canopy variation in seasonal and diurnal reductions in G led to a Ci gradient of approximately 100 m mol mol-1, and the actual canopy Ci gradient was of the same magnitude according to leaf carbon isotope composition. This study demonstrates that stress effects influence Ci more strongly than within-canopy light gradients, and also that leaves acclimated to different irradiance and water stress conditions may regulate water use largely independent of foliar photosynthetic potentials