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The crystal structure of manganotychite has been refined using the holotype specimen from the Alluaiv Mountain, Lovozero massif, Kola peninsula, Russia. The mineral is cubic, Fd$\overline{3}$, a = 14.0015(3) Å, V = 2744.88(18) ų, Z = 8, R₁ = 0.020 for 388 independently observed reflections. Manganotychite is isotypic to tychite and ferrotychite. Its crystal structure is based upon a three-dimensional infinite framework formed by condensation of MnO₆ octahedra and CO₃ groups by sharing common O atoms. The sulfate groups and Na⁺ cations reside in the cavities of the octahedral-triangular metal-carbonate framework. In terms of symmetry and basic construction of the octahedral-triangular framework, the crystal structure of manganotychite is identical to that of northupite, Na₃Mg(CO₃)₂Cl. The transition northupite → tychite can be described as a result of the multiatomic 2Cl⁻ → (SO₄)²⁻ substitution, where both chlorine and sulfate ions are the extra-framework constituents. However, the positions occupied by sulfate groups and chlorine ions correspond to different octahedral cavities within the skeletons of Na atoms. The crystal structure of northupite can be considered as an interpenetration of two frameworks: anionic [Mg(CO₃)₂]²⁻ octahedral-triangular framework and cationic [ClNa₃]²⁻ framework with the antipyrochlore topology. Both manganotychite and northupite structure types can be described as a modification of the crystal structure of diamond (or the dia net) via the following steps: (i) replacement of a vertex of the dia net by an M₄ tetrahedron (no symmetry reduction); (ii) attachment of (CO₃) triangles to the triangular faces of the M₄ tetrahedra (accompanied by the Fd$\overline{3}$m → Fd$\overline{3}$ symmetry reduction); (iii) filling voids of the resulting framework by Na⁺ cations (no symmetry reduction); and (iv) filling voids of the Na skeleton by either sulfate groups (in tychite-type structures) or chlorine atoms (in northupite). As a result, the information-based structural complexity of manganotychite and northupite exceeds that of the dia net. Full article

Improving the toughness of diamond composites has become an industrial demand. In this work, Co₅₀Ni₄₀Fe₁₀ multi-element alloy was designed as binder for diamond-based composites prepared by high temperature and high pressure (HTHP). Two methods of mixing-sintering and infiltration-sintering were used to prepare diamond-based composites with different diamond contents. The phase diagrams of Co-C and Co₅₀Ni₄₀Fe₁₀-C at 6 GPa were calculated by Thermo-Calc. The results show that Co₅₀Ni₄₀Fe₁₀ multi-element alloy promotes the sintering of diamond powder than element Co. The transverse rupture strength (TRS) of sintered diamond with Co₅₀Ni₄₀Fe₁₀ (Co₅₀Ni₄₀Fe₁₀-75 vol% diamond) is higher than that of Co-Comp (Co-75 vol% diamond). The TRS of polycrystalline diamond (PCD) with Co₅₀Ni₄₀Fe₁₀ alloy binder is up to 1360.3 MPa, which is 19.2% higher than Co-PCD. Compared with Co, using Co₅₀Ni₄₀Fe₁₀ as binder results in a less metal residue in PCD, while the metal cluster area is smaller and the metal distribution is more uniform. Full article

In this paper, the compression behavior of a triply minimal periodic surface (Shwartz Diamond) fabricated by selective laser melting (SLM) under different loading rates was studied. A quasi-static strain rate of 2.22 × 10⁻³/s was tested using a universal testing machine, and a strain rate of 650/s was tested by Hopkinson pressure bar (SHPB). The results showed that the yield stress of all structures increased under dynamic load, and the DIF of sheet structure was higher than that of the skeleton structure, among which the DIF of GSHD was the largest and most sensitive to strain rate. However, the normalized SEA of USHD was the highest. Full article

Ribosomopathies are a group of rare diseases in which genetic mutations cause defects in either ribosome biogenesis or function, given specific phenotypes. Ribosomal proteins, and multiple other factors that are necessary for ribosome biogenesis (rRNA processing, assembly of subunits, export to cytoplasm), can be affected in ribosomopathies. Despite the need for ribosomes in all cell types, these diseases result mainly in tissue-specific impairments. Depending on the type of ribosomopathy and its pathogenicity, there are many potential therapeutic targets. The present manuscript will review our knowledge of ribosomopathies, discuss current treatments, and introduce the new therapeutic perspectives based on recent research. Diamond–Blackfan anemia, currently treated with blood transfusion prior to steroids, could be managed with a range of new compounds, acting mainly on anemia, such as L-leucine. Treacher Collins syndrome could be managed by various treatments, but it has recently been shown that proteasomal inhibition by MG132 or Bortezomib may improve cranial skeleton malformations. Developmental defects resulting from ribosomopathies could be also treated pharmacologically after birth. It might thus be possible to treat certain ribosomopathies without using multiple treatments such as surgery and transplants. Ribosomopathies remain an open field in the search for new therapeutic approaches based on our recent understanding of the role of ribosomes and progress in gene therapy for curing genetic disorders. Full article