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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. 

A<sc>bstract</sc> Thep_T-differential cross section ofωmeson production in pp collisions at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV at midrapidity (|y| <0.5) was measured with the ALICE detector at the LHC, covering an unprecedented transverse-momentum range of 1.6< p_T<50 GeV/c. The meson is reconstructed via theω→π⁺π⁻π⁰decay channel. The results are compared with various theoretical calculations: PYTHIA8.2 with the Monash 2013 tune overestimates the data by up to 50%, whereas good agreement is observed with Next-to-Leading Order (NLO) calculations incorporatingωfragmentation using a broken SU(3) model. Theω/π⁰ratio is presented and compared with theoretical calculations and the available measurements at lower collision energies. The presented data triples thep_Tranges of previously available measurements. A constant ratio ofC^ω/π0= 0.578 ± 0.006 (stat.) ± 0.013 (syst.) is found above a transverse momentum of 4 GeV/c, which is in agreement with previous findings at lower collision energies within the systematic and statistical uncertainties. 

In this Letter, the first evidence of the ${}_{\overline{\mathrm{\Lambda }}}{}^4\overline{\mathrm{He}}$antihypernucleus is presented, along with the first measurement at the LHC of the production of (anti)hypernuclei with mass number $A=4$, specifically $\left(\mathrm{anti}\right){}_{\mathrm{\Lambda }}{}^4\mathrm{H}$and $\left(\mathrm{anti}\right){}_{\mathrm{\Lambda }}{}^4\mathrm{He}$. In addition, the antiparticle-to-particle ratios for both hypernuclei ( ${}_{\overline{\mathrm{\Lambda }}}{}^4\overline{\mathrm{H}}/{}_{\mathrm{\Lambda }}{}^4\mathrm{H}$and ${}_{\overline{\mathrm{\Lambda }}}{}^4\overline{\mathrm{He}}/{}_{\mathrm{\Lambda }}{}^4\mathrm{He}$) are shown, which are sensitive to the baryochemical potential of the strongly interacting matter created in heavy-ion collisions. The results are obtained from a data sample of central Pb-Pb collisions, collected during the 2018 LHC data taking at a center-of-mass energy per nucleon pair of $\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$. The yields measured for the average of the charge-conjugated states are found to be $[0.78\pm 0.19\left(\mathrm{stat}\right)\pm 0.17\left(\mathrm{syst}\right)]\times {10}^{-6}$for the $\left(\mathrm{anti}\right){}_{\mathrm{\Lambda }}{}^4\mathrm{H}$and $[1.08\pm 0.34\left(\mathrm{stat}\right)\pm 0.20\left(\mathrm{syst}\right)]\times {10}^{-6}$for the $\left(\mathrm{anti}\right){}_{\mathrm{\Lambda }}{}^4\mathrm{He}$, and the measured antiparticle-to-particle ratios are in agreement with unity. The presence of $\left(\mathrm{anti}\right){}_{\mathrm{\Lambda }}{}^4\mathrm{H}$and $\left(\mathrm{anti}\right){}_{\mathrm{\Lambda }}{}^4\mathrm{He}$excited states is expected to strongly enhance the production yield of these hypernuclei. The yield values exhibit a combined deviation of $3.3\sigma$from the theoretical ground-state-only expectation, while the inclusion of the excited states in the calculations leads to an agreement within $0.6\sigma$with the present measurements. Additionally, the measured $\left(\mathrm{anti}\right){}_{\mathrm{\Lambda }}{}^4\mathrm{H}$and $\left(\mathrm{anti}\right){}_{\mathrm{\Lambda }}{}^4\mathrm{He}$masses are compatible with the world-average values within the uncertainties. © 2025 CERN, for the ALICE Collaboration2025CERN 

A<sc>bstract</sc> Short-range correlations between charged particles are studied via two-particle angular correlations in pp collisions at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV. The correlation functions are measured as a function of the relative azimuthal angle ∆φand the pseudorapidity separation ∆ηfor pairs of primary charged particles within the pseudorapidity interval |η|<0.9 and the transverse-momentum range 1< p_T<8 GeV/c. Near-side (|∆φ|<1.3) peak widths are extracted from a generalised Gaussian fitted over the correlations in full pseudorapidity separation (|∆η|<1.8), while the per-trigger associated near-side yields are extracted for the short-range correlations (|∆η|<1.3). Both are evaluated as a function of charged-particle multiplicity obtained by two different event activity estimators. The width of the near-side peak decreases with increasing multiplicity, and this trend is reproduced qualitatively by the Monte Carlo event generators PYTHIA 8, AMPT, and EPOS. However, the models overestimate the width in the low transverse-momentum region (p_T<3 GeV/c). The per-trigger associated near-side yield increases with increasing multiplicity. Although this trend is also captured qualitatively by the considered event generators, the yield is mostly overestimated by the models in the considered kinematic range. The measurement of the shape and yield of the short-range correlation peak can help us understand the interplay between jet fragmentation and event activity, quantify the narrowing trend of the near-side peak as a function of transverse momentum and multiplicity selections in pp collisions, and search for final-state jet modification in small collision systems. 

A<sc>bstract</sc> The production of (multi-)strange hadrons is measured at midrapidity in proton-proton collisions at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV as a function of the local charged-particle multiplicity in the pseudorapidity interval |η|<0.5 and of the very-forward energy measured by the ALICE Zero-Degree Calorimeters. The latter provides information on the effective energy, i.e. the energy available for particle production in the collision once subtracted from the centre-of-mass energy. The yields of$$ {\textrm{K}}_{\textrm{S}}^0 $$ $K_S^0$,$$ \Lambda +\overline{\Lambda} $$ $\Lambda +\overline{\Lambda }$, and$$ {\Xi}^{-}+{\overline{\Xi}}^{+} $$ ${\Xi }^{-}+{\overline{\Xi }}^{+}$per charged-particle increase with the effective energy. In addition, this work exploits a multi-differential approach to decouple the roles of local multiplicity and effective energy in such an enhancement. The results presented in this article provide new insights into the interplay between global properties of the collision, such as the initial available energy in the event, and the locally produced final hadronic state, connected to the charged-particle multiplicity at midrapidity. Notably, a strong increase of strange baryon production with effective energy is observed for fixed charged-particle multiplicity at midrapidity. These results are discussed within the context of existing phenomenological models of hadronisation implemented in different tunes of the PYTHIA 8 event generator. 

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.