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We have illustrated the presence of spin-glass-like freezing in the Mn-doped spin-chain compounds Ca3Co2-xMnxO6, which was not reported previously. With increasing Mn composition, the magnetic relaxation due to spin freezing is gradually suppressed. Interestingly, the magnetization in the intermediate Mn compositions relaxes more slowly (characteristic time is significantly enhanced) than those in x = 0.0 and 1.0. This could be understood within the framework of disorder with randomness or imperfections, which plays an important role in the formation of spin-glass-like feature in intermediate Mn compositions, quite different from the cases in x = 0.0 with strong spin frustration and in x ∼ 1.0 with perfect Co/Mn ionic order. [ABSTRACT FROM AUTHOR]

We have demonstrated that in Ca3Co2-xScxO6, substitution of nonmagnetic Sc3+ (S = 0) for high-spin Cotrig, even up to the solid solubility limit of x = 0.5-0.6, does not dramatically modify the intrachain ferromagnetic (FM) interaction. This is quite different from the cases of Ir- and Rh-doping, which much enhance the intrachain FM interaction, and the cases of Mn-, Fe-, and Cr-doping, which gradually reduce the intrachain FM interaction, simultaneously introducing antiferromagnetic interaction. The results of band-structure calculations of x = 0.5 are qualitatively consistent with our magnetization data. [ABSTRACT FROM AUTHOR]

Various types of anomalies of inverse dc susceptibility (H/M) have been observed in spin-chain compounds Ca3Co2-xMnxO6. For x = 1.0, the H/M curve exhibits a field-dependent downturn from the paramagnetic Curie-Weiss behavior, signaling the presence of a Griffiths-like cluster phase. A slight decrease of x leads to a rapid suppression of the Griffiths-like singularity, followed by an appearance of field-independent, non-Griffiths-like behavior at x = 0.92. This feature persists until x = 0.33, at and below which the H/M curve presents an unambiguous, field-independent upturn from the Curie-Weiss law. These Mn-doping-dependent anomalies of H/M curves are associated with complex competing magnetic interactions. [ABSTRACT FROM AUTHOR]

Triangular-lattice antiferromagnets with the general formula ATO2 (A =alkali metal, T =3d transition metal) often adopt a slightly distorted crystal structure at low temperatures, accompanying a lifting of magnetic frustration and the appearance of long-range magnetic ordering and sometimes a particular orbital ordering. Taking NaVO2 as an example, we successfully demonstrate that the tiny structural distortion with a ratio of lattice parameters, am/bm =1.755, and the formation of orbital ordering observed in recent neutron-diffraction experiments can be well interpreted by first-principles calculations including 3d electron correlations with parameter Ueff =3.6 eV. This distinct study on "pure" structural distortion is expected to be applied in other triangular-lattice antiferromagnetic systems. [ABSTRACT FROM AUTHOR]

Unusual short-range ferromagnetic (FM) correlations, which can be understood in terms of a Griffiths-like singularity, have been illustrated in the spin-chain compound Ca3CoMnO6 by systematic magnetization measurements. First, these FM correlations can be dramatically suppressed by a small stoichiometric mismatch of Co/Mn atoms. Second, these FM correlations develop at TG = ~125 K, a temperature much higher than the ordering temperature of TN = ~13 K, and survive in magnetic fields of more than 2 T, indicating their robustness. This feature is quite different from the general case—a Griffiths-like anomaly was usually observed in very low magnetic fields and, in many cases, was suppressed in a field of several kilo-oersted. [ABSTRACT FROM AUTHOR]

Importance: Many plant viruses are transmitted by insect vectors in a circulative manner. For efficient transmission, the entry of the virus from vector hemolymph into the primary salivary gland (PSG) is a step of paramount importance. Yet, vector components mediating virus entry into PSG remain barely characterized. Here, we demonstrate the role of clathrin-mediated endocytosis and early endosomes in begomovirus entry into whitefly PSG. Our findings unravel the key components involved in begomovirus transport within the whitefly body and transmission by their whitefly vectors and provide novel clues for blocking begomovirus transmission., Competing Interests: The authors declare no conflict of interest.