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1. Intra- and interband excitations induced residue decay of the Bose polaron in a one-dimensional double-well

   https://doi.org/10.1088/1367-2630/ac51ed  

   Chen, Jie; Mistakidis, Simeon I; Schmelcher, Peter (March 2022, New Journal of Physics)

   Abstract We investigate the polaronic properties of a single impurity immersed in a weakly interacting bosonic environment confined within a one-dimensional double-well potential using an exact diagonalization approach. We find that an increase of the impurity–bath coupling results in a vanishing residue, signifying the occurrence of the polaron orthogonality catastrophe. Asymptotic configurations of the systems’ ground state wave function in the strongly interacting regime are obtained by means of a Schmidt decomposition, which in turn accounts for the observed orthogonality catastrophe of the polaron. We exemplify that depending on the repulsion of the Bose gas, three distinct residue behaviors appear with respect to the impurity–bath coupling. These residue regimes are characterized by two critical values of the bosonic repulsion and originate from the interplay between the intra- and the interband excitations of the impurity. Moreover, they can be clearly distinguished in the corresponding species reduced density matrices with the latter revealing a phase separation on either the one- or the two-body level. The impact of the interspecies mass-imbalance on the impurity’s excitation processes is appreciated yielding an interaction shift of the residue regions. Our results explicate the interplay of intra- and interband excitation processes for the polaron generation in multiwell traps and for designing specific polaron entangled states motivating their exposure in current experiments. 

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2. Dual nature of magnetic nanoparticle dispersions enables control over short-range attraction and long-range repulsion interactions

   https://doi.org/10.1038/s42004-022-00687-3  

   Al Harraq, Ahmed; Hymel, Aubry A.; Lin, Emily; Truskett, Thomas M.; Bharti, Bhuvnesh (June 2022, Communications Chemistry)

   Abstract Competition between attractive and repulsive interactions drives the formation of complex phases in colloidal suspensions. A major experimental challenge lies in decoupling independent roles of attractive and repulsive forces in governing the equilibrium morphology and long-range spatial distribution of assemblies. Here, we uncover the ‘dual nature’ of magnetic nanoparticle dispersions, particulate and continuous, enabling control of the short-range attraction and long-range repulsion (SALR) between suspended microparticles. We show that non-magnetic microparticles suspended in an aqueous magnetic nanoparticle dispersion simultaneously experience a short-range depletion attraction due to the particulate nature of the fluid in competition with an in situ tunable long-range magnetic dipolar repulsion attributed to the continuous nature of the fluid. The study presents an experimental platform for achieving in situ control over SALR between colloids leading to the formation of reconfigurable structures of unusual morphologies, which are not obtained using external fields or depletion interactions alone. 

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3. Quantization of the zigzag model

   https://doi.org/10.1007/JHEP08(2022)047  

   Donahue, John C.; Dubovsky, Sergei (August 2022, Journal of High Energy Physics)

   A bstract The zigzag model is a relativistic integrable N -body system describing the leading high-energy semiclassical dynamics on the worldsheet of long confining strings in massive adjoint two-dimensional QCD. We discuss quantization of this model. We demonstrate that to achieve a consistent quantization of the model it is necessary to account for the non-trivial geometry of phase space. The resulting Poincaré invariant integrable quantum theory is a close cousin of $$ T\overline{T} $$ T T ¯ deformed models. 

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4. Developmental transcriptomes of the sea star, Patiria miniata, illuminate how gene expression changes with evolutionary distance

   https://doi.org/10.1038/s41598-019-52577-9  

   Gildor, Tsvia; Cary, Gregory A.; Lalzar, Maya; Hinman, Veronica F.; Ben-Tabou de-Leon, Smadar (November 2019, Scientific Reports)

   Abstract Understanding how changes in developmental gene expression alter morphogenesis is a fundamental problem in development and evolution. A promising approach to address this problem is to compare the developmental transcriptomes between related species. The echinoderm phylum consists of several model species that have significantly contributed to the understanding of gene regulation and evolution. Particularly, the regulatory networks of the sea star,Patiria miniata(P.miniata), have been extensively studied, however developmental transcriptomes for this species were lacking. Here we generated developmental transcriptomes ofP.miniataand compared these with those of two sea urchins species. We demonstrate that the conservation of gene expression depends on gene function, cell type and evolutionary distance. With increasing evolutionary distance the interspecies correlations in gene expression decreases. The reduction is more severe in the correlations between morphologically equivalent stages (diagonal elements) than in the correlation between morphologically distinct stages (off-diagonal elements). This could reflect a decrease in the morphological constraints compared to other constraints that shape gene expression at large evolutionary divergence. Within this trend, the interspecies correlations of developmental control genes maintain their diagonality at large evolutionary distance, and peak at the onset of gastrulation, supporting the hourglass model of phylotypic stage conservation. 

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5. Genome-Wide SNPs Clarify a Complex Radiation and Support Recognition of an Additional Cat Species

   https://doi.org/10.1093/molbev/msab222  

   Trindade, Fernanda J; Rodrigues, Maíra R; Figueiró, Henrique V; Li, Gang; Murphy, William J; Eizirik, Eduardo (July 2021, Molecular Biology and Evolution)

   Yoder, Anne (Ed.)

   Abstract Phylogenetic reconstruction and species delimitation are often challenging in the case of recent evolutionary radiations, especially when postspeciation gene flow is present. Leopardus is a Neotropical cat genus that has a long history of recalcitrant taxonomic problems, along with both ancient and current episodes of interspecies admixture. Here, we employ genome-wide SNP data from all presently recognized Leopardus species, including several individuals from the tigrina complex (representing Leopardus guttulus and two distinct populations of Leopardus tigrinus), to investigate the evolutionary history of this genus. Our results reveal that the tigrina complex is paraphyletic, containing at least three distinct species. While one can be assigned to L. guttulus, the other two remain uncertain regarding their taxonomic assignment. Our findings indicate that the “tigrina” morphology may be plesiomorphic within this group, which has led to a longstanding taxonomic trend of lumping these poorly known felids into a single species. 

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