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Textural studies of pumice clasts have been used for decades to estimate eruption styles, particularly through bubble size distribution (BSD) analysis along with quantification of vesicle sizes, numbers, connectivity, and crystallization textures. In more recent years, studies have evolved to include finer-scale analysis by scanning electron microscopy (SEM) and large-scale digital elevation models (DEM). By integrating textural, geochemical, and SEM analysis of the vesicularity of pumice clasts, a comprehensive conduit model can be constructed, which can be further used to estimate volatile content and explosivity. In this contribution, we investigate pumice from two Quaternary deposits from the Black Rock Desert and Mineral Mountains located in west central Utah, a first-of-its kind study for these units. In hand sample, the 2.4 Ma crystal-poor Cudahy Mine pumice (SiO2 = 76.1 wt.%) appears characterized by small, uniform bubbles, whereas the <1 Ma Ranch Canyon pumice (SiO2 = 77.5%) contains ample K-feldspar phenocrysts and elongated fibrous vesicles. We employ X-ray tomographic and scanning electron microscopies to determine bubble sphericity and interconnectivity, crystal volumes, and density and vesicularity estimates. Our resulting data are used to establish a model for intra-conduit processes and eruption intensity of these two anorogenic, monogenetic rhyolite volcanoes. These imaging techniques provide a unique way to understand eruption dynamics for ancient volcanoes. 

The supply chains of semiconductors and integrated devices supports industry across all economic sectors. Globally, the supply chain is experiencing a variety of stressors and disruptions, with effects that cascade across the economy, causing product delays and enterprise losses. However, quantitative models that support an understanding of how stressors influence supply chain performance are needed. Here we show how stress testing can be used for assessing the impact of disruptions on supply chain performance metrics and for characterizing system resilience. We demonstrate a framework that utilizes discrete event simulation for stress testing the resilience of a semiconductor supply chain. Our results include a comparison of resilience curves with and without risk management countermeasures, showing the resilience-enhancing benefits of various supply chain management strategies such as maintaining safety stock and sourcing from multiple suppliers. Supply chain managers can utilize stress testing principles and methodologies to configure their supply chain and engage in practices that contribute to system resilience. 

The Atlantic sea scallop supports one of the most lucrative fisheries on the Northeast U.S. shelf. Understanding the interannual variability of sea scallop size structure and associated drivers is critically important for projecting the response of population dynamics to climate change and designing coherent fishery management strategies. In this study, we constructed time series of sea scallop size structures in three rotationally closed areas in the Mid-Atlantic Bight (MAB) and decomposed their total variances using the variance partitioning method. The results suggested that the interannual variances in sea scallop size structures were associated more with thermal stress in regions shallower than 60 m but more with fishing mortality in regions deeper than 60 m. The percentages of small (large) size groups increased (decreased) with elevated thermal stress and fishing pressure. We adopted a scope for growth model to build a mechanistic link between temperature and sea scallop size. Model results suggested a gradual decrease in maximum shell height and habitat contraction under warming. This study quantified the relative contributions of thermal stress and fishing mortality to the variance of scallop size structure and discussed the need for adaptive management plans to mitigate potential socioeconomic impacts caused by size structure changes.

 

Extracting precise cosmology from weak lensing surveys requires modelling the non-linear matter power spectrum, which is suppressed at small scales due to baryonic feedback processes. However, hydrodynamical galaxy formation simulations make widely varying predictions for the amplitude and extent of this effect. We use measurements of Dark Energy Survey Year 3 weak lensing (WL) and Atacama Cosmology Telescope DR5 kinematic Sunyaev–Zel’dovich (kSZ) to jointly constrain cosmological and astrophysical baryonic feedback parameters using a flexible analytical model, ‘baryonification’. First, using WL only, we compare the $S_8$ constraints using baryonification to a simulation-calibrated halo model, a simulation-based emulator model, and the approach of discarding WL measurements on small angular scales. We find that model flexibility can shift the value of $S_8$ and degrade the uncertainty. The kSZ provides additional constraints on the astrophysical parameters, with the joint WL + kSZ analysis constraining $S_8=0.823^{+0.019}_{-0.020}$. We measure the suppression of the non-linear matter power spectrum using WL + kSZ and constrain a mean feedback scenario that is more extreme than the predictions from most hydrodynamical simulations. We constrain the baryon fractions and the gas mass fractions and find them to be generally lower than inferred from X-ray observations and simulation predictions. We conclude that the WL + kSZ measurements provide a new and complementary benchmark for building a coherent picture of the impact of gas around galaxies across observations.

 

Species interactions drive ecosystem processes and are a major focus of global change research. Among the most consequential interactions expected to shift with climate change are those between insect herbivores and plants, both of which are highly sensitive to temperature. Insect herbivores and their host plants display varying levels of synchrony that could be disrupted or enhanced by climate change, yet empirical data on changes in synchrony are lacking. Using evidence of herbivory on herbarium specimens collected from the northeastern United States and France from 1900 to 2015, we provide evidence that plant species with temperature-sensitive phenologies experience higher levels of insect damage in warmer years, while less temperature-sensitive, co-occurring species do not. While herbivory might be mediated by interactions between warming and phenology through multiple pathways, we suggest that warming might lengthen growing seasons for phenologically sensitive plant species, exposing their leaves to herbivores for longer periods of time in warm years. We propose that elevated herbivory in warm years may represent a previously underappreciated cost to phenological tracking of climate change over longer timescales.