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Practicing counter-meta-standardization in Japanese-as-a-Foreign-Language classroom in the US
No full textMathematical modeling insights into improving CAR T cell therapy for solid tumors with bystander effects
No full textAs an adoptive cellular therapy, Chimeric Antigen Receptor T cell (CAR T cell) therapy has shown remarkable success in hematological malignancies but only limited efficacy against solid tumors. Compared with blood cancers, solid tumors present a series of challenges that ultimately combine to neutralize the function of CAR T cells. These challenges include, but are not limited to, antigen heterogeneity - variability in the expression of the antigen on tumor cells, as well as trafficking and infiltration into the solid tumor tissue. A critical question for solving the heterogeneity problem is whether CAR T therapy induces bystander effects, such as antigen spreading. Antigen spreading occurs when CAR T cells activate other endogenous antitumor CD8 T cells against antigens that were not originally targeted. In this work, we develop a mathematical model of CAR T cell therapy for solid tumors that considers both antigen heterogeneity and bystander effects. Our model is based on in vivo treatment data that includes a mixture of target antigen-positive and target antigen-negative tumor cells. We use our model to simulate large cohorts of virtual patients to better understand the relationship involving bystander killing. We also investigate several strategies for enhancing bystander effects, thus increasing CAR T cell therapy’s overall efficacy for solid tumors
Lessons from the Classroom: MEI for Data Scientists
No full textMany data science and computer science students today are familiar with JSON, and may even have worked with APIs to extract data from the web. Ask about XML, however, let alone TEI or MEI, and you are often met with quizzical looks. Yet XML files contain much information that can be productively analyzed with modern data science tools, so training students to leverage these materials is a worthwhile endeavor. The article shows some of the methods we use to help students understand XML as a hierarchical network of elements, how to traverse this network in search of relevant data, and how to harvest XML elements and attributes as tabular data for further analysis. It also reflects on some of the larger lessons learned through all of this work, as students were encouraged to consider the implications of representing the same knowledge in different ways, or what is gained or lost in the transformation of that knowledge from one representation to another
Characterization of human lightness discrimination thresholds for independent spectral variations
No full textThe lightness of an object is an intrinsic property that depends on its surface reflectance spectrum. The visual system estimates an object\u27s lightness from the light reflected off its surface. However, the reflected light also depends on object extrinsic properties of the scene, such as the light source. For stable perception, the visual system needs to discount the variations due to the object extrinsic properties. We characterize this perceptual stability for variation in two spectral properties of the scene: the reflectance spectra of background objects and the intensity of light sources. We measure human observers’ thresholds of discriminating computer-generated images of 3D scenes based on the lightness of a spherical target object in the scene. We measured change in discrimination thresholds as we varied the reflectance spectra of the objects and the intensity of the light sources in the scene, both individually and simultaneously. For small amounts of extrinsic variations, the discrimination thresholds remained nearly constant indicating that the thresholds were dominated by observers’ intrinsic representation of lightness. As extrinsic variation increased, it started affecting observers’ lightness judgment and the thresholds increased. We estimated that the effects of extrinsic variations were comparable to observers’ intrinsic variation in the representation of object lightness. Moreover, for simultaneous variation of these spectral properties, the increase in threshold squared compared to the no-variation condition was a linear sum of the corresponding increase in threshold squared for the individual properties, indicating that the variations from these independent sources combine linearly
Fermi Surface Topology and Magneto-transport Properties of Superconducting Pd3Bi2Se2
No full textPd3Bi2Se2 is a rare realization of a superconducting metal with a nonzero 2 topological invariant. Here, we report the growth of high-quality single crystals of layered Pd3Bi2Se2 with a superconducting transition at c ≈ 0.80 K and upper critical fields of ∼10 and ∼5 mT for the in-plane and out-of-plane directions, respectively. Our density-functional theory (DFT) calculations reveal three pairs of doubly degenerate bands crossing the Fermi level, all displaying clear three-dimensional dispersion consistent with the overall low electronic anisotropy (\u3c2). The multiband electronic nature of Pd3Bi2Se2 is evident in magnetotransport measurements, yielding a sign-changing Hall resistivity at low temperatures. The magnetoresistance is nonsaturating and follows Kohler\u27s scaling rule. We interpret the magnetotransport data in terms of open orbits that are revealed in the DFT-calculated Fermi surface. de Haas–van Alphen (dHvA) oscillation measurements using torque magnetometry on single crystals yield four frequencies for out-of-plane fields: =150±26T, =293±10T, =375±20T, and =1017±12T, with the low frequency dominating the spectrum. Through the measurement of angular-dependent dHvA oscillations and DFT calculations we identify the frequency with an approximately ellipsoidal electron pocket centered on the 2 point of the Brillouin zone. Lifshitz-Kosevich analysis of the dHvA oscillations reveals a small cyclotron effective mass *=(0.11±0.02)0 and a nontrivial Berry phase for the dominant orbit. The presence of nontrivial topology in a bulk superconductor positions Pd3Bi2Se2 as a potential candidate for exploring topological superconductivity
High-Temperature Oxidation-Resistance of Rare-Earth Transition Metal Silicides: Crystal Chemistry Insights from the Sc–Os–Si System
No full textAmid growing interest in space exploration and the development of next-generation nuclear reactors, the demand for multifunctional materials capable of enduring extreme environments is growing. In this context, intermetallic compounds have re-emerged as an area of interest due to their notable structural properties including the ability to withstand high temperatures. The potential for forming ternary and higher-order intermetallics makes them particularly attractive to tune the properties and satisfy the stringent requirements of these applications. The research herein focuses on identifying materials suitable for high-temperature structural applications by synthesizing and characterizing rare-earth transition metal silicides within the Sc–Os–Si system. This system is particularly intriguing because seven unique compounds are uncovered displaying diverse but related crystal chemistries. These include identifying a new, previously unreported structure type and demystifying a previously reported, yet unclear structure type. Each compound’s potential was assessed through Vickers microhardness indentation and thermogravimetric analysis up to 1000 °C. The best-performing material, Sc3Os2Si6, further exhibited outstanding oxidation resistance for over 10 days at 1000 °C, a result attributed to the formation of a passivation layer composed of complex oxides. This study connects the crystal structures across the Sc–Os–Si system while underscoring the potential of identifying resilient materials through fundamental studies of underexplored phase spaces
Rapidly Piloting Real-time Linguistic Assistance for Simultaneous Interpreters with Untrained Bilingual Surrogates
No full textSimultaneous interpretation is a cognitively taxing task, and even seasoned professionals benefit from real-time assistance. However, both recruiting professional interpreters and evaluating new assistance techniques are difficult. We present a novel, realistic simultaneous interpretation task that mimics the cognitive load of interpretation with crowdworker surrogates. Our task tests different real-time assistance methods in a Wizard-of-Oz experiment with a large pool of proxy users and compares against professional interpreters. Both professional and proxy participants respond similarly to changes in interpreting conditions, including improvement with two assistance interventions—translation of specific terms and of numbers—compared to a no-assistance control