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Abstract Ethylene glycol or one of its oxidation products are believed to serve as reducing agents in the shape‐controlled synthesis of Ag nanocubes (NCs) by the polyol process. The identity of end‐groups of polyvinylpyrrolidone (PVP) impacts shape control with alcohol and aldehyde moieties serving as a primary Ag reducing agent. We explored the role of PVP end‐groups in the polyol process by measuring the dependence of particle number density of Ag NCs produced on the initial concentration(s) of Ag and PVP using small angle x‐ray scattering and statistically large particle size distributions analyzed by scanning electron microscopy. The number density of Ag NCs is strongly dependent on the starting concentration of PVP chains demonstrating PVP end‐groups play an important role in the nucleation of NCs. The concentration of Ag⁺is 2 orders of magnitude higher than the end‐groups suggesting ethylene glycol must participate in the reduction of Ag⁺during growth. Perturbation experiments and analysis of resultant particle size distribution reveal nucleation is fast relative to growth of NCs, reinforcing the synergy between PVP end‐groups and ethylene glycol. The evidence demonstrates PVP end‐groups and ethylene glycol are tandem reducing agents operative in temporally distinct phases of the polyol synthesis of Ag NCs. 

Abstract Identifying ways to enable people to reach their creative potential is a core goal of creativity research with implications for education and professional attainment. Recently, we identified a potential barrier to creative achievement: creativity anxiety (i.e., anxiety specific to creative thinking). Initial work found that creativity anxiety is associated with fewer real-world creative achievements. However, the more proximal impacts of creativity anxiety remain unexplored. In particular, understanding how to overcome creativity anxiety requires understanding how creativity anxiety may or may not impact creative cognitive performance, and how it may relate to state-level anxiety and effort while completing creative tasks. The present study sought to address this gap by measuring creativity anxiety alongside several measures of creative performance, while concurrently surveying state-level anxiety and effort. Results indicated that creativity anxiety was, indeed, predictive of poor creative performance, but only on some of the tasks included. We also found that creativity anxiety predicted both state anxiety and effort during creative performance. Interestingly, state anxiety and effort did not explain the associations between creativity anxiety and creative performance. Together, this work suggests that creativity anxiety can often be overcome in the performance of creative tasks, but likewise points to increased state anxiety and effort as factors that may make creative performance and achievement fragile in more demanding real-world contexts. 

Declining coral populations worldwide place a special premium on identifying risks and drivers that precipitate these declines. Understanding the relationship between disease outbreaks and their drivers can help to anticipate when the risk of a disease pandemic is high. Populations of the iconic branching Caribbean elkhorn coralAcropora palmatahave collapsed in recent decades, in part due to white pox disease (WPX). To assess the role that biotic and abiotic factors play in modulating coral disease, we present a predictive model for WPX inA. palmatausing 20 yr of disease surveys from the Florida Keys plus environmental information collected simultaneouslyin situand via satellite. We found that colony size was the most influential predictor for WPX occurrence, with larger colonies being at higher risk. Water quality parameters of dissolved oxygen saturation, total organic carbon, dissolved inorganic nitrogen, and salinity were implicated in WPX likelihood. Both low and high wind speeds were identified as important environmental drivers of WPX. While high temperature has been identified as an important cause of coral mortality in both bleaching and disease scenarios, our model indicates that the relative influence of HotSpot (positive summertime temperature anomaly) was low and actually inversely related to WPX risk. The predictive model developed here can contribute to enabling targeted strategic management actions and disease surveillance, enabling managers to treat the disease or mitigate disease drivers, thereby suppressing the disease and supporting the persistence of corals in an era of myriad threats. 

Relational reasoning is a complex form of human cognition involving the evaluation of relations between mental representations of information. Prior studies have modified stimulus properties of relational reasoning problems and examined differences in difficulty between different problem types. While subsets of these stimulus properties have been addressed in separate studies, there has not been a comprehensive study, to our knowledge, which investigates all of these properties in the same set of stimuli. This investigative gap has resulted in different findings across studies which vary in task design, making it challenging to determine what stimulus properties make relational reasoning—and the putative formation of mental models underlying reasoning—difficult. In this article, we present the Multidimensional Relational Reasoning Task (MRRT), a task which systematically varied an array of stimulus properties within a single set of relational reasoning problems. Using a mixed-effects framework, we demonstrate that reasoning problems containing a greater number of the premises as well as multidimensional relations led to greater task difficulty. The MRRT has been made publicly available for use in future research, along with normative data regarding the relative difficulty of each problem.