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The impact of relative humidity (RH) on organic new particle formation (NPF) from ozonolysis of monoterpenes remains an area of active debate. Previous reports provide contradictory results indicating both depression and enhancement of NPF under conditions of moderate RH, while others do not indicate a potential impact. Only several reports have suggested that the effect may depend on absolute mixing ratio of the precursor volatile organic compound (VOC, ppbv). Herein we report on the impact of RH on NPF from dark ozonolysis of α- and β-pinene at mixing ratios ranging from 0.2 to 80 ppbv. We show that RH enhances NPF (by a factor of eight) at the lowest α-pinene mixing ratio, with a very strong dependence on α-pinene mixing ratio from 4 to 22 ppbv. At higher mixing ratios, the effect of RH plateaus, with resulting modest decreases in NPF. In the case of α- and β-pinene, NPF is enhanced at low mixing ratios due to a combination of chemistry, accelerated kinetics, and reduced partitioning of semi-volatile oxidation products to the particulate phase. Reduced partitioning would limit particle growth, permitting increased gas-phase concentrations of semi- and low-volatility products, which could favor NPF. 

This preliminary study explored how many representations of standard videos, animations/comics, and 360 videos are being used in mathematics methods courses to teach future teachers. Drawing on knowledge from prior studies on standard videos, this study aimed to address the gaps in literature to encompass other representations that are being utilized and obtained. Analyses show that standard videos are the primary medium being used to teach future teachers in math methods, followed by animations/comics, and then 360 videos. Findings suggest that teacher educators are more likely to use a medium that they are more familiar with than a medium with greater perceived usefulness. Further, findings indicate that teacher educators perceived usefulness and frequency of use as not related to their level of familiarity with all representation types, suggesting more factors are at play. 

Numerous threats are putting pollinator health and essential ecosystem pollination services in jeopardy. Although individual threats are widely studied, their co-occurrence may exacerbate negative effects, as posited by the multiple stressor hypothesis. A prominent branch of this hypothesis concerns pesticide–pathogen co-exposure. A landscape analysis demonstrated a positive association between local chlorothalonil fungicide use and microsporidian pathogen ( Nosema bombi ) prevalence in declining bumblebee species ( Bombus spp.), suggesting an interaction deserving further investigation. We tested the multiple stressor hypothesis with field-realistic chlorothalonil and N. bombi exposures in worker-produced B. impatiens microcolonies. Chlorothalonil was not avoided in preference assays, setting the stage for pesticide–pathogen co-exposure. However, contrary to the multiple stressor hypothesis, co-exposure did not affect survival. Bees showed surprising tolerance to Nosema infection, which was also unaffected by chlorothalonil exposure. However, previously fungicide-exposed infected bees carried more transmission-ready spores. Our use of a non-declining bumblebee and potential higher chlorothalonil exposures under some scenarios could mean stronger individual or interactive effects in certain field settings. Yet, our results alone suggest consequences of pesticide co-exposure for pathogen dynamics in host communities. This underlies the importance of considering both within- and between-host processes when addressing the multiple stressor hypothesis in relation to pathogens. 

Immersive videos for training pre-service teachers (PST) are becoming increasingly important and, yet, inadequately investigated. This article focuses on the role of presence as a possible aid in 360 videos for future educators, presenting the results of a study involving 118 PSTs. A multiple factor analysis of the Extended Reality Presence Scale was directed for understanding possible subfactors covering this construct and the potential role of content area and major in influencing PSTs’ viewing experiences. In addition, written noticings regarding 360 videos were collected for exploring correlations between themes noticed and degrees of presence. Results point at 1) three subfactors – i.e., emotional connectivity, co-presence, and awareness of self – composing the feeling of presence, 2) the impact of PSTs’ major on experiencing co-presence, and 3) how presence is positively correlated to a better focus on students and negatively correlated to content in participants’ noticing.