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(−)-Cylindrocyclophane A is a 22-membered C₂-symmetric [7.7]paracyclophane that bears bis-resorcinol functionality and six stereocenters. We report a synthetic strategy for (−)-cylindrocyclophane A that uses 10 C−H functionalization reactions, resulting in a streamlined route with high enantioselectivity and efficiency (17 steps). The use of chiral dirhodium tetracarboxylate catalysis enabled the C–H functionalization of primary and secondary positions, which was complemented by palladium-catalyzed C(sp²)–C(sp²) cross-couplings, resulting in the rapid formation of the macrocyclic core and all stereocenters with high regio-, diastereo-, and enantioselectivity. The use of a late-stage palladium-catalyzed fourfold C(sp²)–H acetoxylation installed the bis-resorcinol moieties. This research exemplifies how multilaboratory collaborations can produce substantial modernizations of complex total synthesis endeavors. 

Question-asking in collaborative dialogue has long been established as key to knowledge construction, both in internal and collaborative problem solving. In this work, we examine probing questions in collaborative dialogues: questions that explicitly elicit responses from the speaker`s interlocutors. Specifically, we focus on modeling the causal relations that lead directly from utterances earlier in the dialogue to the emergence of the probing question. We model these relations using a novel graph-based framework of *deliberation chains*, and realize the problem of constructing such chains as a coreference-style clustering problem. Our framework jointly models probing and causal utterances and the links between them, and we evaluate on two challenging collaborative task datasets: the Weights Task and DeliData. Our results demonstrate the effectiveness of our theoretically-grounded approach compared to both baselines and stronger coreference approaches, and establish a standard of performance in this novel task. 

The power and scope of disease modeling can be markedly enhanced through the incorporation of broad genetic diversity. The introduction of pathogenic mutations into a single inbred mouse strain sometimes fails to mimic human disease. We describe a cross-species precision disease modeling platform that exploits mouse genetic diversity to bridge cell-based modeling with whole organism analysis. We developed a universal protocol that permitted robust and reproducible neural differentiation of genetically diverse human and mouse pluripotent stem cell lines and then carried out a proof-of-concept study of the neurodevelopmental geneDYRK1A. Results in vitro reliably predicted the effects of genetic background onDyrk1aloss-of-function phenotypes in vivo. Transcriptomic comparison of responsive and unresponsive strains identified molecular pathways conferring sensitivity or resilience toDyrk1a1Aloss and highlighted differential messenger RNA isoform usage as an important determinant of response. This cross-species strategy provides a powerful tool in the functional analysis of candidate disease variants identified through human genetic studies. 

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.