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  1. Cores and downhole measurements recovered during International Ocean Discovery Program (IODP) Expedition 376 to Brothers volcano in the Kermadec arc provided unprecedented in situ data in an active submarine arc caldera with extensive hydrothermal alteration. Pressure (P)-wave velocities were measured on the R/V JOIDES Resolution at atmospheric pressures and saturated with seawater. To complement these shipboard measurements, seven new samples were selected representing various primary lithologic and alteration mineralogic compositions in the three deepest holes (U1527C, U1528D, and U1530A) for further shore-based laboratory testing. P- and shear (S)-wave velocities and porosity were measured on seven samples at atmospheric pressure andmore »dry conditions. In addition, P- and S-wave velocities of two of these samples were measured under effective pressure dry and brine saturated. Such data aids in situ porosity, saturation, and pressure sensitivity elastic data interpretation from downhole measurements acquired in Hole U1530A. The clear waveforms obtained and overall similarities to measurements from the nearest shipboard samples ensure that the results are reliable at atmospheric pressures. All shore-based samples have higher porosity than shipboard samples. This difference could be explained by gas- versus water-connected porosity. The two saturated samples measured at effective pressures of the borehole sample depths show that P-wave speeds are 13%–20% higher than the ship atmospheric pressure measurements. The pressure dependence of wave speeds also enables the qualitative interpretation of pore shapes for these submarine, hydrothermally altered rocks.« less
    Free, publicly-accessible full text available August 15, 2023
  2. Free, publicly-accessible full text available October 1, 2023
  3. Abstract We report an Atacama Large Millimeter/submillimeter Array 0.88 mm (Band 7) continuum detection of the accretion disk around SR 12 c, an ∼11 M Jup planetary-mass companion (PMC) orbiting its host binary at 980 au. This is the first submillimeter detection of a circumplanetary disk around a wide PMC. The disk has a flux density of 127 ± 14 μ Jy and is not resolved by the ∼0.″1 beam, so the dust disk radius is likely less than 5 au and can be much smaller if the dust continuum is optically thick. If, however, the dust emission is opticallymore »thin, then the SR 12 c disk has a comparable dust mass to the circumplanetary disk around PDS 70 c but is about five times lower than that of the ∼12 M Jup free-floating OTS 44. This suggests that disks around bound and unbound planetary-mass objects can span a wide range of masses. The gas mass estimated with an accretion rate of 10 −11 M ☉ yr −1 implies a gas-to-dust ratio higher than 100. If cloud absorption is not significant, a nondetection of 12 CO(3–2) implies a compact gas disk around SR 12 c. Future sensitive observations may detect more PMC disks at 0.88 mm flux densities of ≲100 μ Jy.« less
    Free, publicly-accessible full text available April 28, 2023
  4. Free, publicly-accessible full text available March 1, 2023
  5. ABSTRACT Cells do not make fate decisions independently. Arguably, every cell-fate decision occurs in response to environmental signals. In many cases, cell-cell communication alters the dynamics of the internal gene regulatory network of a cell to initiate cell-fate transitions, yet models rarely take this into account. Here, we have developed a multiscale perspective to study the granulocyte-monocyte versus megakaryocyte-erythrocyte fate decisions. This transition is dictated by the GATA1-PU.1 network: a classical example of a bistable cell-fate system. We show that, for a wide range of cell communication topologies, even subtle changes in signaling can have pronounced effects on cell-fate decisions.more »We go on to show how cell-cell coupling through signaling can spontaneously break the symmetry of a homogenous cell population. Noise, both intrinsic and extrinsic, shapes the decision landscape profoundly, and affects the transcriptional dynamics underlying this important hematopoietic cell-fate decision-making system. This article has an associated ‘The people behind the papers’ interview.« less
    Free, publicly-accessible full text available December 15, 2022
  6. Topological line defects are ubiquitous in nature and appear at all physical scales, including in condensed matter systems, nuclear physics, and cosmology. Particularly useful systems to study line defects are nematic liquid crystals (LCs), where they describe singular or nonsingular frustrations in orientational order and are referred to as disclinations. In nematic LCs, line defects could be relatively simply created, manipulated, and observed. We consider cases where disclinations are stabilized either topologically in plane-parallel confinements or by chirality. In the former case, we report on studies in which defect core transformations are investigated, the intriguing dynamics of strength disclinations inmore »LCs exhibiting negative dielectric anisotropy, and stabilization and manipulation of assemblies of defects. For the case of chiral nematics, we consider nanoparticle-driven stabilization of defect lattices. The resulting line defect assemblies could pave the way to several applications in photonics, sensitive detectors, and information storage devices. These excitations, moreover, have numerous analogs in other branches of physics. Studying their universal properties in nematics could deepen understanding of several phenomena, which are still unresolved at the fundamental level.« less
    Free, publicly-accessible full text available March 1, 2023
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  10. Abstract During progression from carcinoma in situ to an invasive tumor, the immune system is engaged in complex sets of interactions with various tumor cells. Tumor cell plasticity alters disease trajectories via epithelial-to-mesenchymal transition (EMT). Several of the same pathways that regulate EMT are involved in tumor-immune interactions, yet little is known about the mechanisms and consequences of crosstalk between these regulatory processes. Here we introduce a multiscale evolutionary model to describe tumor-immune-EMT interactions and their impact on epithelial cancer progression from in situ to invasive disease. Through simulation of patient cohorts in silico, the model predicts that a controllablemore »region maximizes invasion-free survival. This controllable region depends on properties of the mesenchymal tumor cell phenotype: its growth rate and its immune-evasiveness. In light of the model predictions, we analyze EMT-inflammation-associated data from The Cancer Genome Atlas, and find that association with EMT worsens invasion-free survival probabilities. This result supports the predictions of the model, and leads to the identification of genes that influence outcomes in bladder and uterine cancer, including FGF pathway members. These results suggest new means to delay disease progression, and demonstrate the importance of studying cancer-immune interactions in light of EMT.« less
    Free, publicly-accessible full text available December 1, 2022