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The values of cross-section ratio Rk1 of direct k-fold ionization cross section (σk) to direct single ionization cross section (σ1) of Ne impacted by Cq+ (q = 1–3) ions in an energy range of 10 keV/u–500 keV/u are measured in this work. The experimental data are compared with the results from our multi-electron classical over-barrier ionization (ME-COBI) model, showing that the model can give a good estimate to the experimental data. [ABSTRACT FROM AUTHOR]

There exists an interplay between borane and a Lewis base in their adducts. However, studies on these adducts so far have mainly focused on the different reactions of B-H bonds with limited attention given to the influence of borane on the chemistry of the Lewis base, except for BF 3 and BAr 3 . Herein, we have synthesized novel borane adducts with pyridine derivatives, Py·B 3 H 7 , in which the coordination of B 3 H 7 efficiently achieved the intra-molecular charge transfer. The strong B-N bond in these adducts resulted in the formation of stable dearomatic intermediates of pyridine derivatives, confirmed by 1 H and 11 B NMR spectroscopy, from which different reactions have transpired to realize C(sp 3 )-H and C(sp 2 )-H functionalization under mild conditions. The B 3 H 7 pyridine derivatives are stable and do not dissociate or decompose during the reaction process. The high stability of the B-N bond makes this method a good option for boron-containing drugs with potential for use in boron neutron capture therapy (BNCT)., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

MN1 C-terminal truncation (MCTT) syndrome was first reported in 2020 and only 28 patients have been recorded to date. Since MCTT syndrome is a newly defined and rare syndrome with many clinical features, the present study reviewed the manifestations and management of oral and dental anomalies. Gene variants of MCTT syndrome and their positive phenotypes were summarised. The phenotypes of variants in two exons differed from each other mainly in the craniomaxillofacial region, including brain MRI abnormalities and palatal morphology. Pathogenic mechanisms, especially in craniofacial and oral anomalies, were discussed. Appropriate treatments in the stomatology and respiratory departments could improve the symptoms of MCTT syndrome. The different sites of MN1 gene variants may influence the clinical symptoms and there may be racial differences in MCTT syndrome. We recommend oral and pulmonary evaluations for the multidisciplinary treatment of MCTT syndrome.

An efficient method for the synthesis of M 2 B 10 H 14 (M = Na and K) has been developed. The two possible formation mechanisms of the B 10 H 14 2- anion are proposed, in which the NH 2 BH 3 - anion acts as a proton abstractor and a hydride donor. Furthermore, the B 10 H 13 - and B 10 H 15 - intermediates were detected.

The design, synthesis, and applications of new boranes are eternal topics in boron chemistry. A new bis(borane)alkanethiolate salt, K[BH 3 S(CH 3 )BH 3 ], was synthesized in high yield by the reaction of K with (CH 3 ) 2 S·BH 3 at room temperature. The formation mechanism was elucidated based on experimental and theoretical studies. The single-crystal structure of the K[BH 3 S(CH 3 )BH 3 ]·18-crown-6 adduct was determined in which the B-S-B bonding information of K[BH 3 S(CH 3 )BH 3 ] was illustrated for the first time. Using K[BH 3 S(CH 3 )BH 3 ] as a starting material, KB 3 H 8 was successfully synthesized.

All-solid-state potassium batteries are promising candidates in the fields of large-scale energy storage owing to their intrinsic safety, stability, and cost-effectiveness. However, a suitable solid-state electrolyte with high ionic conductivity and favorable interfacial stability is a major challenge for the design and development of these batteries. Herein, we report the synthesis of new KB 3 H 8 · n NH 3 B 3 H 7 ( n = 0.5 and 1) complexes to develop suitable solid-state K-ion conductors for batteries. Both the complexes undergo a reversible phase transition below the thermal decomposition temperature. The optimal KB 3 H 8 ·NH 3 B 3 H 7 delivers a solid-state K-ion conductivity of 1.3 × 10 -4 S cm -1 at 55 °C with an activation energy of 0.44 eV after a transition from a monoclinic to an orthorhombic phase, which is the highest value of K borohydrides reported to date and places KB 3 H 8 ·NH 3 B 3 H 7 among the leading solid-state K-ion conductors. Moreover, KB 3 H 8 ·NH 3 B 3 H 7 reveals a K-ion transference number of nearly 0.93, an electrochemical stability window of 1.2 to 3.5 V vs K + /K, a good capability of K dendrite suppression, and a remarkable stability against the K metal anode due to the formation of the stable interface. These performances make KB 3 H 8 ·NH 3 B 3 H 7 a promising electrolyte for all-solid-state potassium batteries.

All-solid-state K batteries are ideal energy storage devices for grid-scale applications of renewable energies. A novel electrolyte K[B 3 H 7 NH 2 BH 2 NH 2 B 3 H 7 ] with weakly coordinating anions was synthesized. It has a high K + conductivity of 1.01 × 10 -4 S cm -1 at 75 °C, which is probably due to the increased electrostatic potential and size of the anions.

Improved methods for the synthesis of KB 3 H 8 , NH 3 B 3 H 7 , and N -alkyl analogues of NH 3 B 3 H 7 have been developed based on previous works. KB 3 H 8 was synthesized by the reaction of metallic potassium (K) with borane dimethyl sulfide ((CH 3 ) 2 S·BH 3 ) with high yield and atom-economy. In the preparation of NH 3 B 3 H 7 and its N -alkyl analogues, KB 3 H 8 served as a starting material and was converted to THF·B 3 H 7 first through reactions with HCl diethyl ether solution or oxidation agent CoCl 2 . Then, the formed THF·B 3 H 7 in situ reacted with the corresponding ammonia or amines to form the amine borane final products. This work paves an alternative way for preparing organic-inorganic hybrid materials containing B, N, and C atoms.

Objective: To analyze and predict the effect of coronavirus infection on hematopoietic system and potential intervention drugs, and explore their significance for coronavirus disease 2019 (COVID-19)., Methods: The gene expression omnibus (GEO) database was used to screen the whole genome expression data related with coronavirus infection. The R language package was used for differential expression analysis and KEGG/GO enrichment analysis. The core genes were screened by PPI network analysis using STRING online analysis website. Then the self-developed apparent precision therapy prediction platform (EpiMed) was used to analyze diseases, drugs and related target genes., Results: A database in accordance with the criteria was found, which was derived from SARS coronavirus. A total of 3606 differential genes were screened, including 2148 expression up-regulated genes and 1458 expression down-regulated genes. GO enrichment mainly related with viral infection, hematopoietic regulation, cell chemotaxis, platelet granule content secretion, immune activation, acute inflammation, etc. KEGG enrichment mainly related with hematopoietic function, coagulation cascade reaction, acute inflammation, immune reaction, etc. Ten core genes such as PTPRC, ICAM1, TIMP1, CXCR5, IL-1B, MYC, CR2, FSTL1, SOX1 and COL3A1 were screened by protein interaction network analysis. Ten drugs with potential intervention effects, including glucocorticoid, TNF-α inhibitor, salvia miltiorrhiza, sirolimus, licorice, red peony, famciclovir, cyclosporine A, houttuynia cordata, fluvastatin, etc. were screened by EpiMed plotform., Conclusion: SARS coronavirus infection can affect the hematopoietic system by changing the expression of a series of genes. The potential intervention drugs screened on these grounds are of useful reference significance for the basic and clinical research of COVID-19.

The reactions of sodium amidoborane (NaNH 2 BH 3 ) with NiBr 2 have been investigated, and the results showed that black precipitate 1 including the NiBNH x composites could be obtained. From the aqueous solution of the precipitate 1 , the hydrolysis product Ni-B ( 2 ) was isolated and characterized. Both the in situ formed precipitate 1 and the hydrolysis product 2 can catalyze the formation of Na[BH 3 (NH 2 BH 2 ) 2 H]. CoCl 2 showed comparable performance with NiBr 2 . Based on these results, a facile method for the synthesis of Na[BH 3 (NH 2 BH 2 ) 2 H] has been developed. This work provides insights into studying experimental methods for the synthesis of long B/N chain complexes and developing boron and nitrogen chemistry.

Correction for 'Unravelling a general mechanism of converting ionic B/N complexes into neutral B/N analogues of alkanes: Hδ+Hδ- dihydrogen bonding assisted dehydrogenation' by Xi-Meng Chen et al., Chem. Commun., 2019, 55, 12239-12242.

B/N anionic aminoborane linear or branched chain complexes, [BH3(NH2BH2)nH]- (n = 1, 2, and 3) and [BH(NH2BH3)3]-, have been synthesized through the controlled reactions of ammonia borane (NH3BH3) with NaH by adjusting the reactant ratios and reaction temperatures. The possible reaction mechanisms were elucidated based on experimental and theoretical studies.

Long-sought mechanisms for the conversion of diammoniate of diborane ([NH3BH2NH3]+[BH4]-) into NH3BH3 and [NH2BH2]n as well as ammonium aminodiborane ([NH4]+[BH3NH2BH3]-) into a butane analogue, NH3BH2NH2BH3, have been elucidated on the basis of extensive experimental and theoretical studies. The [NH4]+ ammonium cation and the (η2-H2)BH2R moiety are found to be critical in B/N chain expansion.

An efficient synthetic method for MB3H8 (M = Li and Na) has been developed with improved yields on the basis of the investigation of the interconversion between THF·B3H7 and corresponding MB3H8. The mechanism was tentatively proposed based on the understanding of the nucleophilicity of the B-H bonding pair electrons.

Objective: To analyze the molecular markers associated with occurrence, development and poor prognosis of acute myeloid leukemia (AML) by using the data of GEO and TCGA database, as well as multiomics analysis., Methods: The transcriptome data meeting requirements were down-loaded from GEO database, the differentially expressed genes were screened by using the R language limma package, and the GO function enrichment analysis and KEGG pathway analysis were performed for differentially expressed genes, at the same time, the protein interaction network was contracted by using STRING database and cytoscape software to screen out the hub gene, then the prognosis analysis was carried out for hub gene by combination with the clinical information affected in TCGA database., Results: 620 differentially expressed genes were screened out, among which 162 differentially expressed genes were up-regulated, and 458 differentially expressed genes were down-regulated. Based on the results of GO functional enrichment, the KEGG pathway enrichment and protein interaction network, CXCL4, CXCR4, CXCR1, CXCR2, CCL5 and JUN were selected as hub genes. The survival analysis showed that the high expression of CXCL4, CXCR1, and CCL5 was a risk factor for poor prognosis of patiants., Conclusion: CXCL4, CXCR1 and CCL5 can be used as biomarkers for the occurrence and development of AML, which relateds with the unfavorable prognosis and can provide a basis for further study.

A facile synthesis of heavy alkali metal octahydrotriborates (MB 3 H 8 ; M=K, Rb, and Cs) has been developed. It is simply based on reactions of the pure alkali metals with THF⋅BH 3 , does not require the use of electron carriers or the addition of other reaction media such as mercury, silica gel, or inert salts as for previous procedures, and delivers the desired products at room temperature in very high yields. However, no reactions were observed when pure Li or Na was used. The reaction mechanisms for the heavy alkali metals were investigated both experimentally and computationally. The low sublimation energies of K, Rb, and Cs were found to be key for initiation of the reactions. The syntheses can be carried out at room temperature because all of the elementary reaction steps have low energy barriers, whereas reactions of LiBH 4 /NaBH 4 with THF⋅BH 3 have to be carried out under reflux. The high stability and solubility of KB 3 H 8 were examined, and a crystal structure thereof was obtained for the first time., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To screen genes associated with poor prognosis of hepatocellular carcinoma (HCC) and to explore the clinical significance of these genes., Methods: The proper expression profile data of HCC was obtained from the Gene Expression Omnibus (GEO) database, and the differentially expressed genes (DEGs) were identified by differential expression analysis. The DAVID and String database were used for function enrichment analysis and to construct the protein-protein interaction (PPI) network respectively. The Cancer Genome Atlas (TCGA) database and the Cox Proportional Hazard Model were used for prognosis analysis of the DEGs., Results: A eligible human HCC data set (GSE84402) met the requirements. A total of 1141 differentially expressed genes were identified, including 720 up-regulated and 421 down-regulated genes. The results of function enrichment analysis and PPI network performed that CDK1、CDC6、CCNA2、CHEK1、CENPE 、PIK3R1、RACGAP1、BIRC5、KIF11 and CYP2B6 were prognosis key genes. And the prognosis analysis showed that the expressions of CDC6、PIK3R1、KIF11 and RACGAP1 were increased, and the expression of CENPE was decreased, which was closely related to prognosis of HCC., Conclusion: CDC6、CENPE、PIK3R1、KIF11 and RACGAP1 may be closely related to poor prognosis of HCC, and can be used as molecular biomarkers for future research of HCC prognosis.

Objective: To investigate the prognosis-related miRNA histological features and clinical significance of lung adenocarcinoma., Methods: Using The Cancer Genome Atlas (TCGA) data, the miRNA expression profile data of human lung adenocarcinoma were searched for differential analysis, and the prognosis-related miRNAs were screened by Cox risk regression model. The targeted miRNAs were predicted by mirwalk analysis platform, KEGG functional enrichment analysis, and finally, predict the function of prognosis-related miRNAs., Results: A total of 46 differential miRNAs in lung adenocarcinoma were screened, including 19 up-regulated and 27 down-regulated. Six prognostic-related miRNAs were screened by Cox survival analysis, namely hsa-mir-21, hsa-mir-142, hsa-mir-200a high expression, hsa-mir-101, hsa-let-7c, hsa-mir-378e low expression, hsa-mir-21 and hsa-mir-378e were associated with poor prognosis in patients with lung adenocarcinoma, and the survival time was shortened significantly ( P <0.05, AUC=0.618). KEGG analysis showed that the above prognosis-related miRNA targeting regulatory genes were related with immune response pathways, miRNA and cancer pathways, metabolic pathways and so on., Conclusions: Hsa-mir-21 and hsa-mir-378e are associated with poor prognosis of lung adenocarcinoma, and may be used as a molecular marker for prognosis of lung adenocarcinoma after further clinical verification.

Boron compounds are well-known electrophiles. Much less known are their nucleophilic properties. By recognition of the nucleophilicity of the B-H bond, the formation mechanism of octahydrotriborate (B 3 H 8 - ) was elucidated on the bases of both experimental and computational investigations. Two possible routes from the reaction of BH 4 - and THF·BH 3 to B 3 H 8 - were proposed, both involving the B 2 H 6 and BH 4 - intermediates. The two pathways consist of a set of complicated intermediates, which can convert to each other reversibly at room temperature and can be represented by a reaction circle. Only under reflux can the B 2 H 6 and BH 4 - intermediates be converted to B 2 H 5 - and BH 3 (H 2 ) via a high energy barrier, from which H 2 elimination occurs to yield the B 3 H 8 - final product. The formation of B 2 H 6 from THF·BH 3 by nucleophilic substitution of the B-H bond was captured and identified, and the reaction of B 2 H 6 with BH 4 - to produce B 3 H 8 - was confirmed experimentally. On the bases of the formation mechanisms of B 3 H 8 - , we have developed a facile synthetic method for MB 3 H 8 (M = Li and Na) in high yields by directly reacting the corresponding MBH 4 salts with THF·BH 3 . In the new synthetic method for MB 3 H 8 , no electron carriers are needed, allowing convenient preparation of MB 3 H 8 in large scales and paving the way for their wide applications.