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1. $$C^\infty $$C∞ Smoothing for Weak Solutions of the Inhomogeneous Landau Equation

   https://doi.org/10.1007/s00205-019-01465-7  

   Henderson, Christopher; Snelson, Stanley (April 2020, Archive for Rational Mechanics and Analysis)
2. Study of the doubly charmed tetraquark $${{{{{{\rm{T}}}}}}}_{{{{{{\rm{c}}}}}}{{{{{\rm{c}}}}}}}^{+}$$

   https://doi.org/10.1038/s41467-022-30206-w  

   Aaij, R.; Abdelmotteleb, A. S.; Beteta, C. Abellán; Gallego, F. J.; Ackernley, T.; Adeva, B.; Adinolfi, M.; Afsharnia, H.; Agapopoulou, C.; Aidala, C. A.; et al (December 2022, Nature Communications)

   Abstract Quantum chromodynamics, the theory of the strong force, describes interactions of coloured quarks and gluons and the formation of hadronic matter. Conventional hadronic matter consists of baryons and mesons made of three quarks and quark-antiquark pairs, respectively. Particles with an alternative quark content are known as exotic states. Here a study is reported of an exotic narrow state in the D 0 D 0 π + mass spectrum just below the D *+ D 0 mass threshold produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The state is consistent with the ground isoscalar $${{{{{{\rm{T}}}}}}}_{{{{{{\rm{c}}}}}}{{{{{\rm{c}}}}}}}^{+}$$ T c c + tetraquark with a quark content of $${{{{{\rm{c}}}}}}{{{{{\rm{c}}}}}}\overline{{{{{{\rm{u}}}}}}}\overline{{{{{{\rm{d}}}}}}}$$ c c u ¯ d ¯ and spin-parity quantum numbers J P  = 1 + . Study of the DD mass spectra disfavours interpretation of the resonance as the isovector state. The decay structure via intermediate off-shell D *+ mesons is consistent with the observed D 0 π + mass distribution. To analyse the mass of the resonance and its coupling to the D * D system, a dedicated model is developed under the assumption of an isoscalar axial-vector $${{{{{{\rm{T}}}}}}}_{{{{{{\rm{c}}}}}}{{{{{\rm{c}}}}}}}^{+}$$ T c c + state decaying to the D * D channel. Using this model, resonance parameters including the pole position, scattering length, effective range and compositeness are determined to reveal important information about the nature of the $${{{{{{\rm{T}}}}}}}_{{{{{{\rm{c}}}}}}{{{{{\rm{c}}}}}}}^{+}$$ T c c + state. In addition, an unexpected dependence of the production rate on track multiplicity is observed. 

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3. Synthesis and properties of chiral rhenium pentatetraenylidene complexes of the formula [(η5-C5Me5)Re(NO)(PPh3)(CCCCCAr2)]+BF4− (CAr2=9-fluorenylidene)

   https://doi.org/10.1016/S0022-328X(00)00201-1  

   Szafert, Slawomir; Haquette, Pierre; Falloon, Stephen B.; Gladysz, J.A. (June 2000, Journal of Organometallic Chemistry)
4. C – C Coupling of Ethyne to the Carbido Ligand in Products from Reactions with Ru5(μ5-C)(CO)15

   https://doi.org/10.1016/j.jorganchem.2022.122262  

   Adams, Richard D.; Akter, Humaiara; Smith, Mark D. (January 2022, Journal of Organometallic Chemistry)
5. Advancing the Logic of Chemical Synthesis: C−H Activation as Strategic and Tactical Disconnections for C−C Bond Construction

   https://doi.org/10.1002/anie.202011901  

   Lam, Nelson Y. S.; Wu, Kevin; Yu, Jin‐Quan (February 2021, Angewandte Chemie International Edition)

   Abstract The design of synthetic routes by retrosynthetic logic is decisively influenced by the transformations available. Transition‐metal‐catalyzed C−H activation has emerged as a powerful strategy for C−C bond formation, with myriad methods developed for diverse substrates and coupling partners. However, its uptake in total synthesis has been tepid, partially due to their apparent synthetic intractability, as well as a lack of comprehensive guidelines for implementation. This Review addresses these issues and offers a guide to identify retrosynthetic opportunities to generate C−C bonds by C−H activation processes. By comparing total syntheses accomplished using traditional approaches and recent C−H activation methods, this Review demonstrates how C−H activation enabled C−C bond construction has led to more efficient retrosynthetic strategies, as well as the execution of previously unattainable tactical maneuvers. Finally, shortcomings of existing processes are highlighted; this Review illustrates how some highlighted total syntheses can be further economized by adopting next‐generation ligand‐enabled approaches. 

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