Cell size-dependent species sensitivity to nanoparticles underlies changes in phytoplankton diversity and productivity.

Nanoparticle pollution has been shown to affect various organisms. However, the effects of nanoparticles on species interactions, and the role of species traits, such as body size, in modulating these effects, are not well-understood. We addressed this issue using competing freshwater phytoplankton species exposed to copper oxide nanoparticles. Increasing nanoparticle concentration resulted in decreased phytoplankton species growth rates and community productivity (both abundance and biomass). Importantly, we consistently found that nanoparticles had greater negative effects on species with smaller cell sizes, such that nanoparticle pollution weakened the competitive dominance of smaller species and promoted species diversity. Moreover, nanoparticles reduced the growth rate differences and competitive ability differences of competing species, while having little effect on species niche differences. Consequently, nanoparticle pollution reduced the selection effect on phytoplankton community abundance, but increased the selection effect on community biomass. Our results suggest cell size as a key functional trait to consider when predicting phytoplankton community structure and ecosystem functioning in the face of increasing nanopollution.

Rotational Spectrum and Ring Structures of Silacyclohex-2-ene and 1,1-Difluorosilacyclohex-2-ene.

Silacyclohex-2-ene and 1,1-difluorosilacyclohex-2-ene have been synthesized, and the chirped-pulse, Fourier-transform microwave spectra of each have been observed and analyzed from 4.9 to 23.1 GHz. Quantum chemical calculations have been performed at the B3LYP-D3BJ/Def2TZVP level of theory and predict µa to be the largest dipole moment component with a significantly larger value in this component for 1,1-difluorosilacyclohex-2-ene. In accordance with this prediction, the spectra were predominantly a-type with the observation of a few b- and c-type transitions. The signal-to-noise ratio was adequate in both spectra to observe 29Si, 30Si, and all singly substituted 13C isotopologues in natural abundance. All spectra have been fit to a semirigid rotational Hamiltonian and are presented. Analysis of the physical meaning of the fitted parameters is explored and determined to hold for the rotational constants while being more empirical for the centrifugal distortion terms. Experimental structures of both molecules indicate that the quantum chemically calculated structures for the atoms in the ring are a very close depiction of the experimentally determined structures. The structures of each molecule are compared to similar molecules for context, where it is shown that both molecules possess a similar "half-chair" conformation to that of the all-carbon analogue, cyclohexene.

The molecular structure and curious motions in 1,1-difluorosilacyclopent-3-ene and silacyclopent-3-ene as determined by microwave spectroscopy and quantum chemical calculations.

The molecules 1,1-difluorosilacyclopent-3-ene (3SiCPF2) and silacyclopent-3-ene (3SiCP) have been synthesized and studied using chirped pulse, Fourier transform microwave (CP-FTMW) spectroscopy. For 3SiCP this is the first ever microwave study of the molecule and, for 3SiCPF2, the spectra reported in this work have been combined with that of previous work in a global fit. The spectra of each contain splitting which has been fit using a Hamiltonian consisting of semirigid and Coriolis coupling parameters. A refit of the original 3SiCPF2 work was also carried out. All fits and approaches are reported. Analyses of the spectra provide evidence that the molecule is planar which is in agreement with the high-level calculations, but the source of the splitting in the spectra has not been determined.

Building point-of-care ultrasound capacity in rural emergency departments: An educational innovation.

INTRODUCTION: Point-of-care ultrasound (POCUS) use is the standard of care in emergency medicine (EM), but rural physicians face barriers to obtaining and retaining this skill and cite low confidence in their use of POCUS. Without access to high-quality educational opportunities, this important clinical tool may not be used to its full potential in rural hospitals. The Hands-On Ultrasound Education (HOUSE) programme, launched in 2015 by the University of British Columbia's (BC) Division of Rural Continuing Professional Development, is a rurally focused POCUS training and education programme that travels to rural and remote communities and aims to build a rural POCUS community of practice within BC. In this study, we present and evaluate the HOUSE programme. METHODS: The HOUSE programme is described. A comprehensive qualitative evaluation of semi-structured interviews pertaining to HOUSE was conducted in the 4th year of the programme to assess participant experience and programme outcomes. RESULTS: Results from 52 semi-structured interviews indicate that there is a significant increase in self-reported confidence on specific POCUS applications and increased POCUS use after completion of the course, and we report positive experiences with the HOUSE programme. CONCLUSION: By providing a customizable, accessible, hands-on training opportunity, the HOUSE programme removes barriers to POCUS training and education for physicians in rural and remote BC. The rurally focused elements have contributed to education for rural participants that demonstrates increased confidence and the use of POCUS as a clinical tool.

Résumé Introduction: L'échographie ciblée est la norme de soins en médecine d'urgence, mais les médecins des régions rurales ont de la difficulté à acquérir et à retenir cette compétence, et affirment avoir peu d'assurance à utiliser l'échographie ciblée. Privés d'activités d'apprentissage de bonne qualité, les médecins des hôpitaux ruraux n'utilisent pas pleinement cet important outil clinique. Le programme Hands-On Ultrasound Education (HOUSE), lancé en 2015 par la division de formation professionnelle continue en milieu rural de l'Université de la Colombie-Britannique, est un programme de formation axé sur la pratique rurale portant sur l'échographie ciblée. Le programme se déplace dans les communautés rurales et éloignées et il vise à créer une communauté de pratique rurale sur l'échographie ciblée en Colombie-Britannique. Dans cette étude, nous présentons et évaluons le programme HOUSE. Méthodes: Description du programme HOUSE. Une évaluation qualitative complète d'entrevues semi-structurées portant sur HOUSE a été réalisée durant la quatrième année du programme dans le but d'évaluer l'expérience des participants et les résultats du programme. Résultats: Les résultats de 52 entrevues semi-structurées indiquent que la confiance rapportée à l'égard de certaines applications d'échographie ciblée a significativement augmenté, et que l'utilisation de l'échographie ciblée a augmenté après le cours, et nous rapportons des expériences positives envers le programme HOUSE. Conclusion: En offrant des activités d'apprentissage personnalisables, accessibles et pratiques, le programme HOUSE fait tomber les obstacles à la formation sur l'échographie ciblée des médecins des régions rurales et éloignées de la C.-B. Les éléments axés sur les régions rurales ont contribué à l'éducation des participants ruraux qui démontrent une plus grande confiance et une plus grande utilisation de l'échographie ciblée comme outil clinique. Mots-clés: échographie ciblée, formation médicale, médecine d'urgence en milieu rural.

Lingering misinterpretations in garden-path sentences: evidence from a paraphrasing task.

Using a forced-choice question-answering paradigm, K. Christianson, A. Hollingworth, J. F. Halliwell, and F. Ferreira (2001) showed that the original misinterpretation built during the analysis of a garden-path sentence lingers even after reanalysis has occurred. However, their methodology has been questioned (R. P. G. van Gompel, M. J. Pickering, J. Pearson, & G. Jacob, 2006). In this study, the authors report evidence for lingering misinterpretations using a paraphrasing methodology, which is less biased than previous methodologies. Using paraphrasing, they found that garden-path sentences are paraphrased according to a partially reanalyzed interpretation. This finding suggests that the arguments put forward by Christianson et al. are correct: Comprehenders' final interpretations of sentences are often incorrect and do not correspond to the initial input. These findings support the theory that comprehension can occur in a "good-enough" manner (F. Ferreira, V. Ferraro, & K. G. D. Bailey, 2002; F. Ferreira & N. Patson, 2007).