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Abstract This study presents an experimentally validated demonstration of an inverse-optimized binary phase-only gallium oxide diffractive optical element (DOE). This DOE transforms an incident Gaussian beam into a square flat-top beam at the working plane. The design methodology for this binary phase-only DOE beam shaper is founded on an efficient process that integrates the modified Gerchberg-Saxton algorithm and the adjoint method. Experimental characterization of the fabricated device on a single crystal$$(\overline{2} \; 01)$$gallium oxide substrate is conducted at a wavelength of 532 nm, confirming its ability to transform an incident Gaussian beam into a focused square flat-top beam. Such a device holds significant promise for various high-power laser applications, notably in laser welding and similar domains. Furthermore, because of the ultrawide bandgap of gallium oxide, DOEs operating at shorter wavelengths in the UV are also possible based on this technique. 

Abstract Spatial voting models are widely used in political science to analyze legislators’ preferences and voting behavior. Traditional models assume that legislators’ ideal points are static across different types of votes. This article extends the Bayesian spatial voting model to incorporate hierarchical Bayesian methods, allowing for the identification of covariates that explain differences in legislators’ ideal points across voting domains. We apply this model to procedural and final passage votes in the U.S. House of Representatives from the 93rd through 113th Congresses. Our findings indicate that legislators in the minority party and those representing moderate constituencies are more likely to exhibit different ideal points between procedural and final passage votes. This research advances the methodology of ideal point estimation by simultaneously scaling ideal points and explaining variation in these points, providing a more nuanced understanding of legislative voting behavior. 

Abstract In this work, we experimentally measured the pinch‐off of a gas bubble on a biphilic surface, which consisted of an inner circular superhydrophobic region and an outer hydrophilic region. The superhydrophobic region had a radius ofR_SHvarying from 2.8 to 19.0 mm, where the largeR_SHmodeled an infinitely large superhydrophobic surface. We found that during the pinch‐off, the contact line had two different behaviors: for smallR_SH, the contact line was fixed at the boundary of superhydrophobic and hydrophilic regions, and the contact angle gradually increased; in contrast, for largeR_SH, the contact angle was fixed, and the contact line shrank toward the bubble center. Furthermore, we found that regardless of bubble size and contact line behavior, the minimum neck radius collapsed onto a single curve after proper normalizations and followed a power–law relation where the exponent was close to that for bubble pinch‐off from a nozzle. The local surface shapes near the neck were self‐similar. Our results suggest that the surface wettability has a negligible impact on the dynamics of pinch‐off, which is primarily driven by liquid inertia. Our findings improve the fundamental understanding of bubble pinch‐off on complex surfaces. 

Many viscous liquids behave effectively as incompressible under high pressures but display a pronounced dependence of viscosity on pressure. The classical incompressible Navier-Stokes model cannot account for both features, and a simple pressure-dependent modification introduces questions about the well-posedness of the resulting equations. This paper presents the first study of a second-gradient extension of the incompressible Navier-Stokes model, recently introduced by the authors, which includes higher-order spatial derivatives, pressure-sensitive viscosities, and complementary boundary conditions. Focusing on steady flow down an inclined plane, we adopt Barus' exponential law and impose weak adherence at the lower boundary and a prescribed ambient pressure at the free surface. Through numerical simulations, we examine how the flow profile varies with the angle of inclination, ambient pressure, viscosity sensitivity to pressure, and internal length scale. 

Chimeric antigen receptor (CAR) T cell therapy is a relatively new and powerful way of transforming T cells with receptors needed to recognize and kill diseased cells. Traditionally, it involves extraction of T cells from a patient, ex vivo transformation of them with CARs, expansion, and subsequent re-infusion into the patient. Recent developments aim to avoid this lengthy, costly patient-specific procedure by using var- ious viral and non-viral vector particles for direct in vivo delivery of CAR-encoding genes. In this paper we highlight several fundamental connections between in vitro and in vivo aspects of this process. We dis- cuss the proposed use of in vitro-reconstituted virus-like particles (VLPs), prepared from purified CAR- encoding mRNA and viral capsid protein, and functionalized with a T cell-targeting antibody. We compare and contrast these particles – and their use as gene vectors – with the several modalities currently employed that involve in cellulo generation of lentiviral or AAV vectors or in vitro complexation of nucleic acids with cationic polymers or lipid vesicles. We report the unique stoichiometric preciseness and ther- modynamic stability of VLPs formed from anti-HIV-glycoprotein CAR-encoding mRNA and the capsid pro- tein from a plant virus, and quantify the extent to which these monodisperse spherical VLPs are RNase resistant and lead to strong CAR expression in T cells. Further, in vitro cell-killing experiments are pro- posed, in which these CAR VLP-transformed T cells are mixed with HIV-infected cells, to be followed by in vivo experiments involving injection of the particles into HIV-infected humanized mice. 

Abstract The novelty of this study is to present a multilayer framework for predicting the air‐entrained porosity of cement paste based on the molecular characteristics of nonionic surfactants. Air‐entraining agents enhance concrete durability against freeze–thaw damage; however, their development is labor‐intensive and cost‐prohibitive. This research implements a multilayer approach by incorporating three hierarchical layers: the molecular properties of nonionic surfactants (Layer 1), their physicochemical characteristics (Layer 2), and the air‐entrained microstructural porosity of hardened cement paste (Layer 3). By integrating key molecular parameters—such as hydrocarbon chain length, hydrophobicity, and molecular weight—this model effectively predicts the air‐entrained porosity of cement paste. An extensive experimental study was conducted to characterize the physicochemical and microstructural properties of 59 distinct nonionic surfactants. To the best of our knowledge, this represents the first comprehensive dataset of molecular and physicochemical properties of air‐entraining agents reported in the literature. Moreover, no prior study has established such a detailed link between the molecular characteristics of nonionic surfactants and cement microstructure. This dataset served as the foundation for developing the predictive model, which demonstrated the feasibility of this approach in predicting the air‐entraining performance of nonionic admixtures. The developed model facilitates the rapid screening of candidate surfactants and the optimization of their molecular structure while minimizing the need for extensive experimentation. Furthermore, distinct trends emerged from the dataset, offering new insights into the interdependent properties that govern air entrainment in cementitious materials. 

This article considers the problem of modeling a class of nonstationary time series using piecewise autoregressive (AR) processes in the presence of outliers. The number and locations of the piecewise AR segments, as well as the orders of the respective AR processes, are assumed to be unknown. In addition, each piece may contain an unknown number of innovational and/or additive outliers. The minimum description length (MDL) principle is applied to compare various segmented AR fits to the data. The goal is to find the “best” combination of the number of segments, the lengths of the segments, the orders of the piecewise AR processes, and the number and type of outliers. Such a “best” combination is implicitly defined as the optimizer of an MDL criterion. Since the optimization is carried over a large number of configurations of segments and positions of outliers, a genetic algorithm is used to find optimal or near‐optimal solutions. Numerical results from simulation experiments and real data analyses show that the procedure enjoys excellent empirical properties. 

Rates and directions of crustal extension in a continental rift vary in time and space as the rift evolves, and these geologic records are often preserved along fault planes. Some fault-kinematic studies have been undertaken in the central to northern segments of the Rio Grande rift, but similar studies from the southern part of the Rio Grande rift of western Texas, USA, and northern Mexico are fewer. We present new fault-kinematic data from six locations in the southern Rio Grande rift of Trans-Pecos Texas, combined with U-Pb dating of calcite slickenlines, to constrain the directions and time scales of extension. All locations preserve NE-SW−oriented extension, and locations within the Sunken Block graben preserve a more complex kinematic history of multiple extension directions. Four U-Pb ages range from 30.1 ± 3.1 Ma to 13.7 ± 0.9 Ma. Combined with fault-kinematic data and assuming a constant stress regime between 30 Ma and 14 Ma, these data support the interpretation that earliest extension in the southern rift was oriented NE-SW, and extension rotated clockwise to E-W and NW-SE after 13.7 ± 0.9 Ma. Based on available data, this rotation was broadly coincident with rotation in the extension direction in the southern Española basin and in the Basin and Range Province. These differences suggest that extension in the Rio Grande rift responded to the evolving western boundary of the North American plate but included initial underlying driving forces that were supplanted by lateral forces as the transform margin lengthened. Additionally, geochronologic and kinematic data across the Sunken Block graben of the southern Rio Grande rift indicate that the locus of rifting concentrated with time toward the center of this basin; such structural narrowing has previously been demonstrated in the northern segment of the rift. This study provides a much-needed comparison between the southern and northern segments of the rift but highlights the need for more collection of combined kinematic and geochronologic data.