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The anhydrous alkaline earth metal carbonate Be(CO 3 ) was synthesized in a laser-heated diamond anvil cell at moderate pressures and temperatures (20(2) GPa and 1500(200) K) by a reaction of BeO with CO 2 . It crystallizes in the acentric, trigonal space group P 3 1 21 with Z = 3. The crystal structure was obtained from synchrotron single crystal X-ray diffraction data and confirmed by density functional theory-based calculations in combination with Raman spectroscopy. Second harmonic generation measurements were employed to verify the acentric space group symmetry. The crystal structure of Be(CO 3 ) is characterized by the presence of isolated [CO 3 ] 2- -groups and BeO 4 -tetrahedra. This is a new structure type and such a topology has not been observed in carbonates before. Be(CO 3 ) can be recovered to ambient conditions and is not undergoing a phase transition during decompression.

In this study, we conduct extensive high-pressure experiments to investigate phase stability in the cobalt-nitrogen system. Through a combination of synthesis in a laser-heated diamond anvil cell, first-principles calculations, Raman spectroscopy, and single-crystal X-ray diffraction, we establish the stability fields of known high-pressure phases, hexagonal NiAs-type CoN, and marcasite-type CoN 2 within the pressure range of 50-90 GPa. We synthesize and characterize previously unknown nitrides, Co 3 N 2 , Pnma-CoN and two polynitrides, CoN 3 and CoN 5 , within the pressure range of 90-120 GPa. Both polynitrides exhibit novel types of polymeric nitrogen chains and networks. CoN 3 feature branched-type nitrogen trimers (N 3 ) and CoN 5 show π-bonded nitrogen chain. As the nitrogen content in the cobalt nitride increases, the CoN 6 polyhedral frameworks transit from face-sharing (in CoN) to edge-sharing (in CoN 2 and CoN 3 ), and finally to isolated (in CoN 5 ). Our study provides insights into the intricate interplay between structure evolution, bonding arrangements, and high-pressure synthesis in polynitrides, expanding the knowledge for the development of advanced energy materials., (© 2024 Wiley-VCH GmbH.)

The inorganic pyrocarbonate salt Na 2 [C 2 O 5 ] crystallizes in the acentric, monoclinic space group P 2 1 with Z = 2. It contains monovalent alkali metal cations together with isolated pyrocarbonate anions. The [C 2 O 5 ] 2- -groups consist of two planar [CO 3 ] 2- -groups which are slightly tilted with respect to each other around the bridging oxygen atom. Na 2 [C 2 O 5 ] was synthesized in a laser-heated diamond anvil cell at 20(2) GPa by heating a mixture of Na 2 [CO 3 ] + CO 2 to ≈800(200) K. Its crystal structure was obtained by single crystal synchrotron X-ray diffraction and confirmed by density functional theory-based calculations in combination with Raman spectroscopy. Second harmonic generation measurements verified the acentric space group symmetry. The crystal structure is characterized by alternating layers of Na + -cations and [C 2 O 5 ] 2- -complex anions.

The stabilization of nitrogen-rich phases presents a significant chemical challenge due to the inherent stability of the dinitrogen molecule. This stabilization can be achieved by utilizing strong covalent bonds in complex anions with carbon, such as cyanide CN - and NCN 2- carbodiimide, while more nitrogen-rich carbonitrides are hitherto unknown. Following a rational chemical design approach, we synthesized antimony guanidinate SbCN 3 at pressures of 32-38 GPa using various synthetic routes in laser-heated diamond anvil cells. SbCN 3 , which is isostructural to calcite CaCO 3 , can be recovered under ambient conditions. Its structure contains the previously elusive guanidinate anion [CN 3 ] 5- , marking a fundamental milestone in carbonitride chemistry. The crystal structure of SbCN 3 was solved and refined from synchrotron single-crystal X-ray diffraction data and was fully corroborated by theoretical calculations, which also predict that SbCN 3 has a direct band gap with the value of 2.20 eV. This study opens a straightforward route to the entire new family of inorganic nitridocarbonates., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Silicon pernitride, SiN 2 , was synthesized from the elements at 140 GPa in a laser-heated diamond anvil cell. Its crystal structure was solved and refined by means of synchrotron-based single-crystal X-ray diffraction data. The title compound crystallizes in the pyrite structure type (space group Pa , No. 205). The Si atom occupies a site with multiplicity 4 (Wyckoff letter b , site symmetry ..), while the N atom is located on a site with multiplicity 8 (Wyckoff letter c , site symmetry .3.). The crystal structure of SiN 2 is comprised of slightly distorted [SiN 6 ] octa-hedra inter-connected with each other by sharing vertices. Crystal chemical analysis of bond lengths suggests that Si has a formal oxidation state of +IV, while nitro-gen forms pernitride anions (N-N) 4- ., (© Jurzick et al. 2023.)

Crop production is a crucial ecosystem service that requires a combination of natural and anthropogenic contributions to high and stable yields, which is a coproduction process. We analysed this coproduction based on nationally aggregated data for 15 major crops for 67 countries and the European Union with data for four time steps (2000, 2006, 2010, 2014). We found strong increases in fertilizer use, net capital stock and manure use intensity for lower-middle-income countries and stagnation or decrease of these for high-income countries. We used a multiple linear regression model predicting yield to distinguish the effect of anthropogenic contributions (crop-specific fertilizer use intensity, net capital stock intensity, manure use intensity) and natural contributions (crop-specific agricultural suitability, including soil characteristics, topography and climate). We found that in particular fertilizer use intensity, manure use intensity and agricultural suitability explained variation in yields to a considerable degree (R 2  = 0.62).

Production of eukaryotic ribosomal subunits is a highly dynamic process; pre-ribosomes undergo numerous structural rearrangements that establish the architecture present in mature complexes and serve as key checkpoints, ensuring the fidelity of ribosome assembly. Using in vivo crosslinking, we here identify the pre-ribosomal binding sites of three RNA helicases. Our data support roles for Has1 in triggering release of the U14 snoRNP, a critical event during early 40S maturation, and in driving assembly of domain I of pre-60S complexes. Binding of Mak5 to domain II of pre-60S complexes promotes recruitment of the ribosomal protein Rpl10, which is necessary for subunit joining and ribosome function. Spb4 binds to a molecular hinge at the base of ES27 facilitating binding of the export factor Arx1, thereby promoting pre-60S export competence. Our data provide important insights into the driving forces behind key structural remodelling events during ribosomal subunit assembly.

The impact of RNA structures in coding sequences (CDS) within mRNAs is poorly understood. Here, we identify a novel and highly conserved mechanism of translational control involving RNA structures within coding sequences and the DEAD-box helicase Dhh1. Using yeast genetics and genome-wide ribosome profiling analyses, we show that this mechanism, initially derived from studies of the Brome Mosaic virus RNA genome, extends to yeast and human mRNAs highly enriched in membrane and secreted proteins. All Dhh1-dependent mRNAs, viral and cellular, share key common features. First, they contain long and highly structured CDSs, including a region located around nucleotide 70 after the translation initiation site; second, they are directly bound by Dhh1 with a specific binding distribution; and third, complementary experimental approaches suggest that they are activated by Dhh1 at the translation initiation step. Our results show that ribosome translocation is not the only unwinding force of CDS and uncover a novel layer of translational control that involves RNA helicases and RNA folding within CDS providing novel opportunities for regulation of membrane and secretome proteins., (© 2017 Jungfleisch et al.; Published by Cold Spring Harbor Laboratory Press.)

Ribosome biogenesis in yeast requires 75 small nucleolar RNAs (snoRNAs) and a myriad of cofactors for processing, modification, and folding of the ribosomal RNAs (rRNAs). For the 19 RNA helicases implicated in ribosome synthesis, their sites of action and molecular functions have largely remained unknown. Here, we have used UV cross-linking and analysis of cDNA (CRAC) to reveal the pre-rRNA binding sites of the RNA helicase Rok1, which is involved in early small subunit biogenesis. Several contact sites were identified in the 18S rRNA sequence, which interestingly all cluster in the "foot" region of the small ribosomal subunit. These include a major binding site in the eukaryotic expansion segment ES6, where Rok1 is required for release of the snR30 snoRNA. Rok1 directly contacts snR30 and other snoRNAs required for pre-rRNA processing. Using cross-linking, ligation and sequencing of hybrids (CLASH) we identified several novel pre-rRNA base-pairing sites for the snoRNAs snR30, snR10, U3, and U14, which cluster in the expansion segments of the 18S rRNA. Our data suggest that these snoRNAs bridge interactions between the expansion segments, thereby forming an extensive interaction network that likely promotes pre-rRNA maturation and folding in early pre-ribosomal complexes and establishes long-range rRNA interactions during ribosome synthesis., (© 2014 Martin et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.)

We report light- and electron microscopic findings in glomerular amyloidosis (secondary amyloidosis), which occurred after recurrent empyema of the pleura. After healing of the empyema, the clinical symptoms disappeared, over a period of eight years. During the acute stage of the disease (grade II-III amyloidosis) when the nephrotic syndrome was present, amyloid deposits were seen in the mesangium and on both sides of the basement membrane of the glomerular capillaries. Furthermore, denuded basement membrane areas showing the passage of amyloid into the urinary space, and invaginations of the podocyte by straightened amyloid fibrils were found. After clinical recovery (except for a trace of proteinuria), the renal amyloidosis had electronmicroscopically transformed from an active into an inactive or resting form, while the amount of amyloid present was almost the same. In the areas of amyloid deposits, reparative changes were observed, espcially in the area of the mesangial cells and of the podocytes. The podocytes were separated from the persisting amyloid deposits by newly formed basement membrane material.