Lanthanum(III) triggers AtrbohD- and jasmonic acid-dependent systemic endocytosis in plants

Trivalent rare earth elements (REEs) are widely used in agriculture. Aerially applied REEs enter leaf epidermal cells by endocytosis and act systemically to improve the growth of the whole plant. The mechanistic basis of their systemic activity is unclear. Here, we show that treatment of Arabidopsis leaves with trivalent lanthanum [La(III)], a representative of REEs, triggers systemic endocytosis from leaves to roots. La(III)-induced systemic endocytosis requires AtrbohD-mediated reactive oxygen species production and jasmonic acid. Systemic endocytosis impacts the accumulation of mineral elements and the development of roots consistent with the growth promoting effects induced by aerially applied REEs. These findings provide insights into the mechanistic basis of REE activity in plants.

Structural distortions of orthorhombic RFeO3 and RMnO3

We will address in detail the structural distortions responsible for the symmetry lowering of the ideal cubic Pm-3m perovskite to the orthorhombic Pnma structure of RFeO3 and RMnO3 (R = trivalent rare-earth cation), important to the stabilization of the different magnetic and multiferroic phases in these materials. We will also show how the Amplimodes tool of Bilbao Crystallographic Server is useful in quantifying these distortions and establish which phonons can be used as probes of both the octahedra tilting and deformation.

The Silicon-hybrid Carbon Dot Derived from Rice Husk: A promising fluorescent probe for trivalent rare earth element ions in aqueous media

Silicon-hybrid carbon dot (Si-CD) was synthesized using the rice husk as a raw material via the carbonization and further acid-cutting method. The as-prepared Si-CD can be well dispersed in water...

Distorted Te nets in the modulated crystal structures of RETe1.94(1) (RE = La, Pr, Nd)

The two-dimensionally incommensurately modulated crystal structures of the compounds RETe1.94(1) (RE = La, Pr, Nd) were investigated by single-crystal X-ray diffraction. The compounds crystallize in the tetragonal superspace group P4/n(αβ½)00(−βα½)00 (No. 85.2.58.2) with q 1 = αa*+βb*+½c* and q 2 = −βa*+αb*+½c* and share a common motif of an alternating stacking of a puckered [RETe] layer and a planar [Te] layer. This basic structural motif is observed for all reported compounds with unusually large anisotropic displacement parameters in the planar [Te] layer. Taking the modulation into account, a distortion from this perfect square planar net is noted along with vacancies in the planar [Te] layer. The distortion leads to the formation of different discrete anions, like Te2−, Te2 2− and Te3 2−, similar to previously reported structures for RE X 2–δ compounds (RE = trivalent rare earth metal, X = S, Se, Te). The Te–Te distances in the modulated [Te] layer are found in a narrow range as compared to those in the corresponding sulfides and selenides.

Kinetics of luminescence calcium gallate activated by Yb3+, Er3+ ions

The paper presents the results of a study of the luminescent properties of calcium gallate activated by trivalent rare earth ions Yb3+ and Er3+. IR luminescence spectra of samples with a single activator Ca1‑хYbxGa2O4,Ca1‑хErxGa2O4 were studied when excited by radiation sources with a wavelength of 940 and 790 nm, respectively. The dependence of the luminescence intensity of samples on the concentration of rare earth ions is obtained. When the two-activator composition of Ca1‑х‑yYbxEryGa2O4 is excited by a semiconductor laser diode with a wavelength of 940 nm, IR luminescence is registered in the regions of 980-1100 nm and 1450-1670 nm. The radiation in these bands corresponds to electronic transitions in Yb3+ and Er3+ ions, respectively. For a luminescence band with a maximum at a wavelength of 1540 nm, the excitation spectra were measured, the maximum intensity is at the wavelengths: 930, 941, 970, 980 nm. The dependence of the IR luminescence intensity of a solid solution of Ca1‑х‑yYbxEryGa2O4 on the concentration of Er3+ ions was studied. With an increase in the concentration of Er3+ ions in the luminescence spectra, there is a redistribution in the intensity of the bands belonging to Yb3+ and Er3+ ions, which indicates the presence of energy transfer processes between these ions. The kinetics of IR luminescence attenuation was studied for series with one and two activators: Ca1‑хYbxGa2O4,Ca1‑хErxGa2O4, Ca1‑х‑yYbxEryGa2O4. It is established that the luminescence attenuation occurs mainly according to the exponential law, which indicates the predominance of the intracenter luminescence mechanism in the studied structures. Based on the analysis of the excitation and luminescence spectra of experimental samples, conclusions are made about the interaction of Yb3+ and Er3+ activator ions in the crystal lattice of calcium gallate.

Influence of trivalent rare earth (Dy3+) ions substitution on the structural, magnetic and dielectric properties of nanosized Ni0.6Cd0.4DyxFe2‒xO4 ferrites

The authors have requested that this preprint be withdrawn due to erroneous posting.