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This paper is concerned with numerical algorithms for Biot model. By introducing an intermediate variable, the classical 2-field Biot model is written into a 3-field formulation. Based on such a 3-field formulation, we propose a coupled algorithm, some time-extrapolation based decoupled algorithms, and an iterative decoupled algorithm. Our focus is the analysis of the iterative decoupled algorithm. It is shown that the convergence of the iterative decoupled algorithm requires no extra assumptions on physical parameters or stabilization parameters. Numerical experiments are provided to demonstrate the accuracy and efficiency of the proposed method. 

Does interdisciplinary collaboration make a difference when it comes to communicating engineering concepts to community audiences? This research focuses on the effect of communication strategies on community attitudes toward engineering research. Two cohorts of four academic researchers each, representing eight different disciplinary backgrounds (aviation planning, cancer research, math education, musicology, chemical/biomolecular engineering, material science, soil science, and theater) developed research communication outputs for the public by creating: 1) an individual video presenting their research through the lens of their discipline alone; and 2) a convergent video where they collaboratively discussed their research with others in their cohort around a common theme, integrating all of their disciplinary lenses. Using a panel of respondents (n = 2,938) procured through Qualtrics, and purposefully recruited to create a diverse sample in age and racial/ethnic background, the research team randomly assigned respondents to watch one of three video treatments: one individual video, multiple individual videos, or a convergent video. Then, respondents answered a series of questions about their interest and knowledge of several STEM topics, both before and after watching the video(s). This retrospective pre/post questionnaire technique helps to alleviate response-shift bias present in self-assessed changes in learning attitudes. Our findings show that collaborative presentation videos increased self-reported audience interest in engineering, and perceptions of disciplinary relatedness more than the non-collaborative, individual presentations made by the same researchers. These results suggest a beneficial role for collaborative communication strategies to foster interest in engineering among public audiences, even among people without a background in STEM. Further, collaborative communication led to an increased sense of relatedness among different disciplines, which may be useful for effective public research communication about interdisciplinary engineering projects. 

Aims. We perform a simulation using the Astrophysical Multipurpose Software Environment of the Orion Trapezium star cluster in which the evolution of the stars and the dynamics of planetary systems are taken into account. Methods. The initial conditions from earlier simulations were selected in which the size and mass distributions of the observed circumstellar disks in this cluster are satisfactorily reproduced. Four, five, or size planets per star were introduced in orbit around the 500 solar-like stars with a maximum orbital separation of 400 au. Results. Our study focuses on the production of free-floating planets. A total of 357 become unbound from a total of 2522 planets in the initial conditions of the simulation. Of these, 281 leave the cluster within the crossing timescale of the star cluster; the others remain bound to the cluster as free-floating intra-cluster planets. Five of these free-floating intra-cluster planets are captured at a later time by another star. Conclusions. The two main mechanisms by which planets are lost from their host star, ejection upon a strong encounter with another star or internal planetary scattering, drive the evaporation independent of planet mass of orbital separation at birth. The effect of small perturbations due to slow changes in the cluster potential are important for the evolution of planetary systems. In addition, the probability of a star to lose a planet is independent of the planet mass and independent of its initial orbital separation. As a consequence, the mass distribution of free-floating planets is indistinguishable from the mass distribution of planets bound to their host star. 

The ALICE Collaboration reports measurements of the large relative transverse momentum ( $k_T$) component of jet substructure in $pp$and Pb-Pb collisions at center-of-mass energy per nucleon pair $\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$. Enhancement in the yield of such large- $k_{\mathrm{T}}$emissions in head-on Pb-Pb collisions is predicted to arise from partonic scattering with quasiparticles of the quark-gluon plasma. The analysis utilizes charged-particle jets reconstructed by the anti- $k_{\mathrm{T}}$algorithm with resolution parameter $R=0.2$in the transverse-momentum interval $60<p_{\mathrm{T},\mathrm{ch},\mathrm{jet}}<80\mathrm{GeV}/c$. The soft drop and dynamical grooming algorithms are used to identify high transverse momentum splittings in the jet shower. Comparison of measurements in Pb-Pb and $pp$collisions shows medium-induced narrowing, corresponding to yield suppression of high- $k_T$splittings, in contrast to the expectation of yield enhancement due to quasiparticle scattering. The measurements are compared to theoretical model calculations incorporating jet modification due to jet-medium interactions (“jet quenching”), both with and without quasiparticle scattering effects. These measurements provide new insight into the underlying mechanisms and theoretical modeling of jet quenching. 

A<sc>bstract</sc> We report on the measurement of inclusive, non-prompt, and prompt J/ψ-hadron correlations by the ALICE Collaboration at the CERN Large Hadron Collider in pp collisions at a center-of-mass energy of 13 TeV. The correlations are studied at midrapidity (|y| <0.9) in the transverse momentum rangesp_T<40 GeV/cfor the J/ψand 0.15< p_T<10 GeV/cand |η|<0.9 for the associated hadrons. The measurement is based on minimum bias and high multiplicity data samples corresponding to integrated luminosities ofL_int= 34 nb⁻¹andL_int= 6.9 pb⁻¹, respectively. In addition, two more data samples are employed, requiring, on top of the minimum bias condition, a threshold on the tower energy ofE= 4 and 9 GeV in the ALICE electromagnetic calorimeters, which correspond to integrated luminosities ofL_int= 0.9 pb⁻¹andL_int= 8.4 pb⁻¹, respectively. The azimuthally integrated near and away side yields of associated charged hadrons per J/ψtrigger are presented as a function of the J/ψand associated hadron transverse momentum. The measurements are discussed in comparison to PYTHIA calculations. 

This study proposes a novel disinfection process by sequential application of peracetic acid (PAA) and ultra-violet light (UV), on the basis of elucidation of disinfection mechanisms under UV/PAA. Results show that hydroxyl radicals, generated by UV-activated PAA, contribute to the enhanced inactivation of Escherichia coli under UV/PAA compared to PAA alone or UV alone. Furthermore, the location of hydroxyl radical generation is a critical factor. Unlike UV/H2O2, which generates hydroxyl radicals mainly in the bulk solution, the hydroxyl radicals under UV/PAA are produced close to or inside E. coli cells, due to PAA diffusion. Therefore, hydroxyl radicals exert significantly stronger disinfection power under UV/PAA than under UV/H2O2 conditions. Pre-exposing E. coli to PAA in the dark followed by application of UV (i.e., a PAA-UV/PAA process) promotes diffusion of PAA to the cells and achieves excellent disinfection efficiency while saving more than half of the energy cost associated with UV compared to simultaneous application of UV and PAA. The effectiveness of this new disinfection strategy has been demonstrated not only in lab water but also in wastewater matrices. 

The production yields of the orbitally excited charm-strange mesons ${\mathrm{D}}_{\mathrm{s}1}\left(1^{+}\right)(2536{)}^{+}$and ${\mathrm{D}}_{\mathrm{s}2}^{*}\left(2^{+}\right)(2573{)}^{+}$were measured for the first time in proton-proton (pp) collisions at a center-of-mass energy of $\sqrt{s}=13\mathrm{TeV}$with the ALICE experiment at the LHC. The ${\mathrm{D}}_{\mathrm{s}1}^{+}$and ${\mathrm{D}}_{\mathrm{s}2}^{*+}$mesons were measured at midrapidity ( $\left|y\right|<0.5$) in minimum-bias and high-multiplicity pp collisions in the transverse-momentum interval $2<p_{\mathrm{T}}<24\mathrm{GeV}/c$. Their production yields relative to the ${\mathrm{D}}_{\mathrm{s}}^{+}$ground-state yield were found to be compatible between minimum-bias and high-multiplicity collisions, as well as with previous measurements in ${\mathrm{e}}^{\pm }\mathrm{p}$and ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$collisions. The measured ${\mathrm{D}}_{\mathrm{s}1}^{+}/{\mathrm{D}}_{\mathrm{s}}^{+}$and ${\mathrm{D}}_{\mathrm{s}2}^{*+}/{\mathrm{D}}_{\mathrm{s}}^{+}$yield ratios are described by statistical hadronization models and can be used to tune the parameters governing the production of excited charm-strange hadrons in Monte Carlo generators, such as 8.