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Emergency medical services (EMS) providers often face significant challenges in their work, including collecting, integrating, and making sense of a variety of information. Despite their criticality, EMS work is one of the very few medical domains with limited technical support. To design and implement effective decision support, it is essential to examine and gain a holistic understanding of the fine-grained process of sensemaking in the field. To that end, we reviewed 25 video recordings of EMS simulations to understand the nuances of EMS sensemaking work, including 1) the types of information and situation that are collected and made sense of in the field; 2) the work practices and temporal patterns of EMS sensemaking work; and 3) the challenges in EMS sensemaking and decision-making process. Based on the results, we discuss implications for technology opportunities to support rapid information acquisition and sensemaking in time-critical, high-risk medical settings such as EMS. 

The receiver function (RF) is a widely used crustal imaging technique. In principle, it assumes relatively noise-free traces that can be used to target receiver-side structures following source deconvolution. In practice, however, mode conversions and reflections may be severely degraded by noisy conditions, hampering robust estimation of crustal parameters. In this study, we use a sparsity-promoting Radon transform to decompose the observed RF traces into their wavefield contributions, i.e., direct conversions, multiples, and incoherent noise. By applying a crustal mask on the Radon-transformed RF, we obtain noise-free RF traces with only Moho conversions and reflections. We demonstrate, using a synthetic experiment and a real data example from the Sierra Nevada, that our approach can effectively de-noise the RFs and extract the underlying Moho signals. This greatly improves the robustness of crustal structure recovery as exemplified by subsequent $H-\kappa$ stacking. We further demonstrate, using a station sitting on loose sediments in the Upper Mississippi Embayment, that a combination of our approach and frequency-domain filtering can significantly improve crustal imaging in reverberant settings. We expect that our technique will enable high-resolution crustal imaging and inspire more applications of Radon transforms in seismic signal processing. 

Molecular clocks are the basis for dating the divergence between lineages over macroevolutionary timescales (~10⁵to 10⁸years). However, classical DNA-based clocks tick too slowly to inform us about the recent past. Here, we demonstrate that stochastic DNA methylation changes at a subset of cytosines in plant genomes display a clocklike behavior. This “epimutation clock” is orders of magnitude faster than DNA-based clocks and enables phylogenetic explorations on a scale of years to centuries. We show experimentally that epimutation clocks recapitulate known topologies and branching times of intraspecies phylogenetic trees in the self-fertilizing plantArabidopsis thalianaand the clonal seagrassZostera marina, which represent two major modes of plant reproduction. This discovery will open new possibilities for high-resolution temporal studies of plant biodiversity.

 

We propose a V-shape PSF generated from double axicon lenses in the collection path of wide-field microscopes for 3D high-resolution imaging with an extended depth of field. 

In recent decades, the widespread use of wind power has led to the rise of a new environmental issue
in the form of wind turbine blade waste. To combat the landfilling and incineration of what is
projected to be millions of tons GFRP blades, the Re-Wind Network aims to find solutions to
repurpose wind blades in structural applications. This paper reports on the design and analysis of three
options for an 18.5 meter pedestrian bridge made using decommissioned 53-meter blades. Maximum
strains and deflections found through structural analysis of these BladeBridges are used to assess the
feasibility of each option.