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1. PAIRING BY A DYNAMICAL INTERACTION IN A METAL

   https://doi.org/10.31857/S004445102104012X  

   CHUBUKOV, A. V.; ABANOV, AR. (January 2021, ЖУРНАЛ ЭКСПЕРИМЕНТАЛЬНОЙ И ТЕОРЕТИЧЕСКОЙ ФИЗИКИ)

   null (Ed.)
2. Deoxydehydration of polyols catalyzed by a molybdenum dioxo-complex supported by a dianionic ONO pincer ligand

   https://doi.org/10.1039/C9DT03759D  

   Tran, Randy; Kilyanek, Stefan M. (November 2019, Dalton Transactions)

   Deoxydehydration (DODH) is the net reduction of diols and polyols to alkenes or dienes and water. Molybdenum cis -dioxo bis-phenolate ONO complexes were synthesized and have been shown to be active for DODH. Catalysts were screened for activity at 150–190 °C, and appreciable yields of up to 59% were obtained. PPh 3 , Na 2 SO 3 , Zn, C, 3-octanol and 2-propanol were screened as reductants. Additionally, the reactivities of a variety of diols were screened. With ( R , R )-(+)-hydrobenzoin as substrate, DODH occurs via a mechanism where reduction of the Mo catalyst is a result of diol oxidation to form two equivalents of aldehyde. These reactions result in complete conversion and near quantitative yields of trans-stilbene and benzaldehyde. 

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3. Bubble deformation by a turbulent flow

   https://doi.org/10.1017/jfm.2021.379  

   Perrard, Stéphane; Rivière, Aliénor; Mostert, Wouter; Deike, Luc (August 2021, Journal of Fluid Mechanics)

   We investigate the modes of deformation of an initially spherical bubble immersed in a homogeneous and isotropic turbulent background flow. We perform direct numerical simulations of the two-phase incompressible Navier–Stokes equations, considering a low-density bubble in the high-density turbulent flow at various Weber numbers (the ratio of turbulent and surface tension forces) using the air–water density ratio. We discuss a theoretical framework for the bubble deformation in a turbulent flow using a spherical harmonic decomposition. We propose, for each mode of bubble deformation, a forcing term given by the statistics of velocity and pressure fluctuations, evaluated on a sphere of the same radius. This approach formally relates the bubble deformation and the background turbulent velocity fluctuations, in the limit of small deformations. The growth of the total surface deformation and of each individual mode is computed from the direct numerical simulations using an appropriate Voronoi decomposition of the bubble surface. We show that two successive temporal regimes occur: the first regime corresponds to deformations driven only by inertial forces, with the interface deformation growing linearly in time, in agreement with the model predictions, whereas the second regime results from a balance between inertial forces and surface tension. The transition time between the two regimes is given by the period of the first Rayleigh mode of bubble oscillation. We discuss how our approach can be used to relate the bubble lifetime to the turbulence statistics and eventually show that at high Weber numbers, bubble lifetime can be deduced from the statistics of turbulent fluctuations at the bubble scale. 

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4. Patterning a Leaf by Establishing Polarities

   https://doi.org/10.3389/fpls.2020.568730  

   Manuela, Darren; Xu, Mingli (October 2020, Frontiers in Plant Science)

   null (Ed.)
5. Social predation by a nudibranch mollusc

   https://doi.org/10.1101/2024.07.01.600874  

   Otter, Kate; Gomidova, Saida; Katz, Paul S (July 2024, bioRxiv)

   Abstract Social predation is a common strategy used by predators to subdue and consume prey. Animals that use this strategy have many ways of finding each other, organizing behaviors and consuming prey. There is wide variation in the extent to which these behaviors are coordinated and the stability of individual roles. This study characterizes social predation by the nudibranch mollusc,Berghia stephanieae, which is a specialist predator that eats only the sea anemone,Exaiptasia diaphana. A combination of experimental and modeling approaches showed thatB. stephanieaedoes predate uponE. diaphanain groups. The extent of social feeding was not altered by length of food deprivation, suggesting that animals are not shifting strategies based on internal state. It was unclear what cues the individualBerghiaused to find each other; choice assays testing whether they followed slime trails, were attracted to injured anemones, or preferred conspecifics feeding did not reveal any cues. Individuals did not exhibit stable roles, such as leader or follower, rather the population exhibited fission-fusion dynamics with temporary roles during predation. Thus, theBerghiaprovides an example of a specialist predator of dangerous prey that loosely organizes social feeding, which persists across hunger states and uses temporary individual roles; however, the cues that it uses for aggregation are unknown. Significance StatementSocial predation is a strategy to hunt dangerous prey and minimize injury. Many nudibranchs specialize as predators of cnidarians, which are dangerous to them. Although nudibranchs are typically characterized as solitary hunters, we provide evidence that social predation strategies may be used by a species that specializes on one species of sea anemone. The study showed that the individual sea slugs assumed temporary roles for establishing groups and that the group dynamics were unstable. However, the cues that the nudibranchs use to aggregate remain elusive. 

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