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We test a subset of intonational contrasts proposed in the Autosegmental-Metrical model for American English for evidence of contrast enhancement in phonologically and phonetically longer vs. shorter intervals. F0 trajectories were assessed from 32 speakers’ imitated productions of six tonally distinct tunes, e.g., HHH, HHL. Maximally three tune shapes emerge from clustering analyses of imitated f0 trajectories, each cluster comprising imitations of two phonetically similar but phonologically distinct tunes. We find enhancement of tune contrasts between the emergent clusters in measures of f0 differences (RMSD, end f0, center of gravity). There is no evidence of enhancement for phonetically similar tunes grouped within the same cluster, though fine-grained phonetic distinctions are detected for these “lost” tune contrasts, suggesting a reanalysis as within-category variation. 

Recent work on rising declaratives proposes a distinction between steep inquisitive rising declaratives and shallow assertive rising declaratives. Yet, it is unclear whether this contrast arises from a phonological distinction of the pitch accent used or a phonetic distinction in the scaling of the boundary tone target. In two perception experiments, we evaluate the contributions of pitch accent and boundary tone in the interpretation of assertive force. In Exp. 1, we find a counterintuitive result for the weighting of pitch accent, which is better understood from the perspective of the Tonal Center of Gravity. This perspective provides a path forward for Exp. 2, which shows no evidence of a contribution from the pitch accent in the interpretation of assertive force. Results speak against a phonological contrast in subtypes of rising declaratives and suggest a need for more narrow investigation in the phonetic domain. 

What is the minimal mathematical model that can generate the F0 trajectories for a system of pitch accents? In this work, we propose a nonlinear coupled dynamical systems theory of American English pitch accents with a single basic parameter. As that parameter increases, F0 profiles for different pitch accents are generated. The terms in the differential equation are based on a novel dynamical analysis of a large database of F0 productions in terms of measurements of F0 peak, peak velocity, and the time to achieve peak velocity. We describe the basic dynamical properties of pitch accents in our database and argue for the proposed model as the simplest one that realizes all the major dynamic F0 properties of the pitch accent system. We argue that the proposed model describes both abstract phonological and concrete phonetic aspects of the system. 

Great Salt Lake hosts an ecosystem that is critical to migratory birds and international aquaculture, yet it is currently threatened by falling lake elevation and high lakewater salinity resulting from water diversions in the upstream watershed and the enduring megadrought in the western United States. Microbialite reefs underpin the ecosystem, hosting a surface microbial community that is estimated to contribute 30% of the lake’s primary productivity. We monitored exposure, desiccation, and bleaching over time in an area of microbialite reef. During this period, lake elevation fell by 1.8 m, and salinity increased from 11.0% to 19.5% in open-water portions of the outer reef, reaching halite saturation in hydrologically closed regions. When exposed, microbialite bleaching was rapid. Bleached microbialites are not necessarily dead, however, with communities and chlorophyll persisting beneath microbialite surfaces for several months of exposure and desiccation. However, superficial losses in the mat community resulted in enhanced microbialite weathering. In microbialite recovery experiments with bleached microbialite pieces, partial community recovery was rapid at salinities ≤ 17%. 16S and 18S rRNA gene sequencing indicated that recovery was driven by initial seeding from lakewater. At higher salinity levels, eventual accumulation of chlorophyll may reflect accumulation and preservation of lake material in halite crusts vs. true recovery. Our results indicate that increased water input should be prioritized in order to return the lake to an elevation that submerges microbialite reefs and lowers salinity levels. Without quick action to reverse diversions in the watershed, loss of pelagic microbial community members due to sustained high salinity could prevent the recovery of the ecosystem-critical microbialite surface communities in Great Salt Lake. 

Granulomas often form around pathogens that cause chronic infections. Here, we discover an innate granuloma model in mice with an environmental bacterium calledChromobacterium violaceum. Granuloma formation not only successfully walls off, but also clears, the infection. The infected lesion can arise from a single bacterium that replicates despite the presence of a neutrophil swarm. Bacterial replication ceases when macrophages organize around the infection and form a granuloma. This granuloma response is accomplished independently of adaptive immunity that is typically required to organize granulomas. TheC. violaceum-induced granuloma requires at least two separate defense pathways, gasdermin D and iNOS, to maintain the integrity of the granuloma architecture. This innate granuloma successfully eradicatesC. violaceuminfection. Therefore, thisC. violaceum-induced granuloma model demonstrates that innate immune cells successfully organize a granuloma and thereby resolve infection by an environmental pathogen.

 

Abstract Global pollinator declines threaten food production and natural ecosystems. The drivers of declines are complicated and driven by numerous factors such as pesticide use, loss of habitat, rising pathogens due to commercial bee keeping and climate change. Halting and reversing pollinator declines will require a multidisciplinary approach and international cooperation. Here, we summarize 20 presentations given in the symposium ‘Protecting pollinators and our food supply: Understanding and managing threats to pollinator health’ at the 19th Congress of the International Union for the Study of Social Insects in San Diego, 2022. We then synthesize the key findings and discuss future research areas such as better understanding the impact of anthropogenic stressors on wild bees.