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Theoretical modeling of the solid‐state photocatalysis is one of the important issues as various useful photocatalysts have been developed to date. In this work, we investigated the mechanism of the alcohol photooxidation on niobium oxide (Nb2O5) which was experimentally developed, using the density functional theory (DFT)/time‐dependent (TD)DFT calculations based on the cluster model. The alcohol adsorption and the first hydrogen transfer from hydroxy group to surface occur in the ground state, while the second hydrogen transfer from CH proceeds in the excited states during the photoirradiation of UV or visible light. The spin crossing was identified and the low‐lying triplet states were solved for the reaction pathway. The photoabsorption in the visible light region was characterized as the charge transfer transition from O 2p of alcohol to Nb 4d of the Nb2O5 surface. The spin density and the natural population analysis indicated the generation of spin density in the moiety of carbonyl compound and its dissipation to the interface of the surface, which partly explains the electron paramagnetic resonance measurement. It was confirmed that the rate determining step is the desorption of carbonyl compound and water molecule in agreement with the experimental rate equation analysis. The present findings with the theoretical modeling will provide useful information for the further studies of the solid‐state photocatalysis. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: As the promising catalysts for the water‐gas shift (WGS) reaction, the activity of Au‐CeO2 composites is susceptible to the aggregation size and electronic state of Au species. Previous reports were extensively focused on the discrepancy between nonmetallic Au and metallic Au nanoparticles, whereas the understanding of the authentic role of the isolated Au atoms was limited. Herein, we investigated the catalytic behavior and structural information over two types of Au/CeO2 catalysts, in which the predominant conjunctions were isolated Au1‐CeO2 and Aun‐CeO2, respectively. Based on comprehensive characterizations, particularly by in‐situ Raman and in‐situ DRIFTS, we found that the isolated Au atoms were responsible for enhancing the reducibility of the CeO2 matrix. The CO adsorption ability on the isolated Au sites was significantly inferior to clustered Au atoms, especially at relatively high temperatures (> 200 °C). As a result, the boosted O vacancy on the isolated Au1‐CeO2 conjunctions could improve the H2O activation ability for the Au‐CeO2 catalysts and demonstrate a comparable activity to the clustered Aun‐CeO2 sites. This work might deepen understanding of the catalytic function for the isolated Au1 site within Au/CeO2 systems while catalyzing the WGS reaction. [ABSTRACT FROM AUTHOR]

The oxides and active metals at the interface synergistically activate reactants and thus promote the reaction, but the interface structure often changes dynamically during the reaction. In the conventional supported catalysts, the metals at the interface have been extensively studied, while the structural evolution of oxides is often overlooked due to the interference of the bulk phase signal. In this work, CeO2−CuO inverse catalysts are designed to reveal the dynamic structure evolution of CeO2 in the CeO2−CuO system during the water gas shift (WGS) reaction by in situ Raman, in situ XRD, quasi in situ XPS, and near ambient pressure XPS (NAP‐XPS). CeO2 is partially concealed in the CuO phase in the un‐pretreated catalyst and gradually exposed to the surface, forming an inverse CeOx/Cu structure during the reducing process. This structure exhibits a high catalytic activity in the WGS reaction and remains durable under the reductive conditions. When the inverse CeOx/Cu structure is exposed to the non‐redox conditions, the reconfiguration of the reduced oxide is observed which is caused by the oxygen migration of CeO2. This work explores the structure evolution of CeO2 in CeO2−CuO inverse catalyst under different conditions by in situ characterization technique and provides a reference for monitoring the dynamic changes of oxide structure. [ABSTRACT FROM AUTHOR]

Background: Interleukin (IL)‐17A is involved in the pathogenesis of allergic rhinitis (AR). Increased expression of IL‐17A is correlated with disease severity and nasal eosinophilia. However, the molecular mechanisms by which IL‐17A contributes to T‐helper 2 cytokine IL‐13‒driven pathology in AR remain unclear. We sought to obtain mechanistic insight into how IL‐17A and IL‐13 regulate the epithelial production of eotaxin‐3 representing eosinophilic inflammation in AR. Methods: Human nasal epithelial cells (HNECs) from AR patients were cultured and stimulated with IL‐17A, IL‐13, or IL‐17A and IL‐13. Phosphorylated signal transducer activator of transcription 6 (p‐STAT6) and suppressor of cytokine signaling 1 (SOCS1) in HNECs were assayed using Western blotting. Immunocytochemistry was used to determine p‐STAT6‒positive expression in the cells. Eotaxin‐3 expression in the cells and culture supernatants was evaluated using real‐time polymerase chain reaction and enzyme‐linked immunosorbent assays. Results: Stimulation with IL‐13 alone induced STAT6 phosphorylation and promoted p‐STAT6 nuclear translocation, leading to eotaxin‐3 production by HNECs. These effects were further enhanced by cotreatment with IL‐13 and IL‐17A, whereas IL‐17A alone had no impact on STAT6 or eotaxin‐3 expression. Incubation with IL‐17A or IL‐13 increased the level of SOCS1 protein in the cells, whereas the addition of IL‐17A attenuated IL‐13‒induced SOCS1 expression. Conclusion: IL‐17A potentiated IL‐13‒driven STAT6 activation through the downregulation of SOCS1 expression, leading to enhancement of eotaxin‐3 production by HNECs. These factors contributed to eosinophilic inflammation in AR. [ABSTRACT FROM AUTHOR]

Aims/Introduction: The aim of the present study was to identify candidate differentially expressed genes (DEGs) and pathways using bioinformatics analysis, and to improve our understanding of the cause and potential molecular events of diabetic nephropathy. Materials and Methods: Two cohort profile datasets (GSE30528 and GSE33744) were integrated and used for deep analysis. We sorted DEGs and analyzed differential pathway enrichment. DEG‐associated ingenuity pathway analysis was carried out. The screened gene expression feature was verified in the db/db mouse kidney cortex. Then, rat mesangial cells cultured with high‐concentration glucose were used for verification. The target genes of transcriptional factor E26 transformation‐specific‐1 (ETS1) were predicted with online tools and validated using chromatin immunoprecipitation assay quantitative polymerase chain reaction. Results: The two GSE datasets identified 89 shared DEGs; 51 were upregulated; and 38 were downregulated. Most of the DEGs were significantly enriched in cell adhesion, the plasma membrane, the extracellular matrix and the extracellular region. Quantitative reverse transcription polymerase chain reaction analysis validated the upregulated expression of Itgb2, Cd44, Sell, Fn1, Tgfbi and Il7r, and the downregulated expression of Igfbp2 and Cd55 in the db/db mouse kidney cortex. Chromatin immunoprecipitation assay quantitative polymerase chain reaction showed that Itgb2 was the target gene of transcription factor Ets1. ETS1 knockdown in rat mesangial cells decreased integrin subunit beta 2 expression. Conclusion: We found that EST1 functioned as an important transcription factor in diabetic nephropathy development through the promotion of integrin subunit beta 2 expression. EST1 might be a drug target for diabetic nephropathy treatment. [ABSTRACT FROM AUTHOR]

Although the existence of Stone-Wales (5-7) defect at graphene edge has been clarified experimentally, theoretical study on the formation mechanism is still imperfect. In particular, the regioselectivity of multistep reactions at edge (self-reconstruction and growth with foreign carbon feedstock) is essential to understand the kinetic behavior of reactive boundaries but investigations are still lacking. Herein, by using finite-sized models, multistep reconstructions and carbon dimer additions of a bared zigzag edge are introduced using density functional theory calculations. The zigzag to 5-7 transformation is proved as a site-selective process to generate alternating 5-7 pairs sequentially and the first step with largest barrier is suggested as the rate-determining step. Conversely, successive C2 insertions on the active edge are calculated to elucidate the formation of 5-7 edge during graphene growth. A metastable intermediate with a triple sequentially fused pentagon fragment is proved as the key structure for 5-7 edge formation. © 2017 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

High-surface-area Co-SiO2 nanocomposites were synthesized by a simple two-step procedure with activated carbon as the template. These materials catalyze the decomposition of ammonia to produce COx-free hydrogen. The fresh and used catalysts were characterized by various techniques including X-ray diffraction, N2 adsorption-desorption, and transmission electron microscopy. Furthermore, temperature-programmed reduction by hydrogen combined with the corresponding in situ XRD analysis was performed to investigate the redox properties of the as-prepared catalysts. The strong interaction between the cobalt species and silica can effectively prevent the active cobalt nanoparticles from agglomerating during calcination and the ammonia decomposition reaction. The ammonia reaction rate reached about 7000 mol NH3 molCo-1 h-1 with a very high GHSV of 124 000 cm3gcat-1 h-1 at 600 8C; this rate was maintained for 48h without any observable deactivation of the as-obtained Co-SiO2 nanocomposite catalyst. [ABSTRACT FROM AUTHOR]

The open edge reconstruction of half-saturated (6,0) zigzag carbon nanotube (CNT) was introduced by density functional calculations. The multistep rearrangement was demonstrated as a regioselective process to generate a defective edge with alternating pentagons and heptagons. Not only the thermal stability was found to be enhanced significantly after reconstruction but also the total spin of CNT was proved to be reduced gradually from high-spin septet to close-shell singlet, revealing the critical role of deformed edge on the geometrical and magnetic properties of open-ended CNTs. Kinetically, the initial transformation was confirmed as the rate-determining step with relatively the largest reaction barrier and the following steps can take place spontaneously. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Iminosulfane(phosphane)carbon(0) derivatives (iSPCs; Ar3P→C←SPh2(NMe); Ar=Ph ( 1), 4-MeOC6H4 ( 2), 4-(Me2N)C6H4 ( 3)) have been successfully synthesized and the molecular structure of 3 characterized. Carbone 3 is the first thermally and hydrolytically stable carbone stabilized by phosphorus and sulfur ligands. DFT calculations reveal the electronic structures of 1- 3, which have two lone pairs of electrons at the carbon center. First and second proton affinity values are theoretically calculated to be in the range of 286.8-301.1 and 189.6-208.3 kcal mol−1, respectively. Cyclic voltammetry measurements reveal that the HOMO energy levels follow the order of 3> 2> 1 and the HOMO of 3 is at a higher energy than those of bis(chalcogenane)carbon(0) (BChCs). The reactivities of these lone pairs of electrons are demonstrated by the C-diaurated and C-proton-aurated complexes. These results are the first experimental evidence of phosphorus- and sulfur-stabilized carbones behaving as four-electron donors. In addition, the reaction of hydrochloric salts of the carbones with Ag2O gives the corresponding AgI complexes. The resulting silver(I) carbone complexes can be used as carbone transfer agents. This synthetic protocol can also be used for moisture-sensitive carbone species. [ABSTRACT FROM AUTHOR]

A series of novel bis‐benzothiazole derivatives with head‐to‐head orientation were designed, synthesized, and evaluated for their anti‐proliferative activities on U937, HL60, and HeLa cells. A significant part of the targets exhibited considerable in vitro anticancer activity, and some of them were more potent than the reference 5‐FU. Molecular modeling, fluorescence, and viscosimetry studies revealed that these compounds could bind into the minor groove of DNA. Amongst them, the most active compound 7 with IC50 in a range of 6.76 to 8.67 μM against the tested three cell lines, which was 1.46–2.47 and 3.48–4.93 times more potent than 5‐FU and Hoechst 33258, respectively, warrant further investigations. [ABSTRACT FROM AUTHOR]

Objective: We aimed to characterise glioblastomas of adolescents and young adults (AYAs) that were isocitrate dehydrogenase (IDH) wild type (wt) and H3wt. Materials and Methods: Fifty such patients (aged 16–32) were studied by methylation profiling, targeted sequencing and targeted RNA‐seq. Results: Tumours predominantly clustered into three methylation classes according to the terminology of Capper et al. (2018): (anaplastic) pleomorphic xanthoastrocytoma (PXA) (21 cases), GBM_midline (15 cases) and glioblastoma RTK/mesenchymal (seven cases). Two cases clustered with ANA_PA, four cases with LGG classes and one with GBM_MYCN. Only fifteen cases reached a calibrated score >0.84 when the cases were uploaded to DKFZ Classifier. GBM_midline‐clustered tumours had a poorer overall survival (OS) compared with the PXA‐clustered tumours (p = 0.030). LGG‐clustered cases had a significantly better survival than GBM_midline‐clustered tumours and glioblastoma RTK/mesenchymal‐clustered tumours. Only 13/21 (62%) of PXA‐clustered cases were BRAF V600E mutated. Most GBM_midline‐clustered cases were not located in the midline. GBM_midline‐clustered cases were characterised by PDGFRA amplification/mutation (73.3%), mutations of mismatch repair genes (40.0%), and all showed H3K27me3 and EZH1P loss, and an unmethylated MGMT promoter. Across the whole cohort, MGMT promoter methylation and wt TERT promoter were favourable prognosticators. Mismatch repair gene mutations were poor prognosticators and together with methylation class and MGMT methylation, maintained their significance in multivariate analyses. BRAF mutation was a good prognosticator in the PXA‐clustered tumours. Conclusion: Methylation profiling is a useful tool in the diagnosis and prognostication of AYA glioblastomas, and the methylation classes have distinct molecular characteristics. The usual molecular diagnostic criteria for adult IDHwt glioblastoma should be applied with caution within the AYA age group. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Transition metal‐rare earth oxide catalysts had the ability to catalyze ammonia decomposition according to recent years' scientific reports. However, most of those catalysts had their own limitations: the catalytic activity was poor, and/or the active species could not clearly be identified. Here we report the CoaSmbOx catalysts with good dispersion, controllable content, and excellent catalytic performance for ammonia decomposition. The various content catalysts were synthesized by aerosol‐assisted self‐assembly approach. These catalysts had high dispersion and great morphology according to the images of the transmission electron microscope (TEM) and the scanning electron microscope (SEM). The temperature‐programmed reduction by hydrogen (H2‐TPR) and in‐situ X‐ray diffraction (XRD) results indicated that the interaction between cobalt oxide and samarium oxide influenced the redox properties of cobalt oxide. Combined with in‐situ Raman, we found that Co0 was an active species of the CoaSmbOx catalysts in ammonia decomposition. Moreover, the temperature‐programmed desorption of NH3 (NH3‐TPD) data illustrated that the addition of Sm was beneficial to the adsorption of NH3. In general, we successfully obtained the CoaSmbOx catalyst with high activity and good stability. More importantly, we have identified the structure‐function relationship of catalysts by exploring the active species in the reaction process. [ABSTRACT FROM AUTHOR]

Electronic effects on the central carbon atom of carbone, generated by the replacement of the SIV ligand of carbodisulfane (CDS) with other chalcogen ligands (Ph2E, E=S or Se), were investigated. The carbones Ph2E→C←SPh2(NMe) [E=S( 1) or Se( 2)] were synthesized from the corresponding salts, and their molecular structures and electronic properties were characterized. The carbone 2 is the first carbone containing selenium as the coordinated atom. DFT calculations revealed the electronic structures of 1 and 2, which have two lone pairs of electrons at the carbon center. The trend in HOMO energy levels, estimated by cyclic voltammetry measurements, for the carbones and CDS follows the order of 2> 1>CDS. Analysis of a doubly protonated dication and trication complex revealed that the central carbon atom of 2 behaves as a four-electron donor. [ABSTRACT FROM AUTHOR]

Electronic effects on the central carbon atom of carbone, generated by the replacement of the SIV ligand of carbodisulfane (CDS) with other chalcogen ligands (Ph2E, E=S or Se), were investigated. The carbones Ph2E→C←SPh2(NMe) [E=S( 1) or Se( 2)] were synthesized from the corresponding salts, and their molecular structures and electronic properties were characterized. The carbone 2 is the first carbone containing selenium as the coordinated atom. DFT calculations revealed the electronic structures of 1 and 2, which have two lone pairs of electrons at the carbon center. The trend in HOMO energy levels, estimated by cyclic voltammetry measurements, for the carbones and CDS follows the order of 2> 1>CDS. Analysis of a doubly protonated dication and trication complex revealed that the central carbon atom of 2 behaves as a four-electron donor. [ABSTRACT FROM AUTHOR]

In the 2016, WHO classification of tumors of the central nervous system, isocitrate dehydrogenase (IDH) mutation is a main classifier for lower grade astrocytomas and IDH‐mutated astrocytomas is now regarded as a single group with longer survival. However, the molecular and clinical heterogeneity among IDH mutant lower grade (WHO Grades II/III) astrocytomas have only rarely been investigated. In this study, we recruited 160 IDH mutant lower grade (WHO Grades II/III) astrocytomas, and examined PDGFRA amplification, CDKN2A deletion and CDK4 amplification by FISH analysis, TERT promoter mutation by Sanger sequencing and ATRX loss and p53 expression by immunohistochemistry. We identified PDGFRA amplification, CDKN2A homozygous deletion and CDK4 amplification in 18.8%, 15.0% and 18.1% of our cohort respectively, and these alterations occurred in a mutually exclusive fashion. PDGFRA amplification was associated with shorter PFS (P = 0.0003) and OS (P < 0.0001). In tumors without PDGFRA amplification, CDKN2A homozygous deletion or CDK4 amplification was associated with a shorter OS (P = 0.035). Tumors were divided into three risk groups based on the presence of molecular alterations: high risk (PDGFRA amplification), intermediate risk (CDKN2A deletion or CDK4 amplification) and low risk (neither CDKN2A deletion and CDK4 amplification nor PDGFRA amplification). These three risk groups were significantly different in overall survival with mean survivals of 40.5, 62.9 and 71.5 months. The high‐risk group also demonstrated a shorter PFS compared to intermediate‐ (P = 0.036) and low‐risk (P < 0.0001) groups. One limitation of this study is the relatively short follow‐up period, a common confounding factor for studies on low‐grade tumors. Our data illustrate that IDH mutant lower grade astrocytomas is not a homogeneous group and should be molecularly stratified for risk. [ABSTRACT FROM AUTHOR]

Background: Porcine infectious pleuropneumonia caused by Actinobacillus pleuropneumoniae (App) is one of the most serious infectious diseases in pigs and has brought huge economic losses to the world pig industry. The aim of this trial was to evaluate the effect of enteric‐coated tilmicosin granule in the treatment and control of artificial infection of App. Methods: Sixty Duroc and Yorkshire crossbred pigs (50 of which were artificially infected) were divided into six groups: BCG (Blank control group), ICG (Infection‐only control group), HDG (High‐dose enteric‐coated tilmicosin granules), MDG (Medium‐dose enteric‐coated tilmicosin granules), LDG (Low‐dose enteric‐coated tilmicosin granules) and TPG (Tilmicosin premix drug control group). The cure rate, mortality, clinical respiratory score, body temperature score, weight gain, lung score and so on were recorded. Results: The cure rate of HDG and MDG was as high as 90%, the mortality was 10%, and the clinical signs recovered quickly. Conclusion: The results showed that enteric‐coated tilmicosin granules had obvious therapeutic effect on artificial infection, which could reduce the damage caused by the disease and reduce the mortality. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRs) were involved in numerous cardiovascular diseases, especially ischemic heart diseases, but the miR changes during cardiac ischemia–reperfusion (I/R) injury following sevoflurane (SEV) preconditioning are still unknown. This study aims to investigate the effect of miR‐874 on cardiac I/R injury in mouse models pretreated with SEV. Following establishment of mouse models with myocardial I/R injury, mice were pretreated with SEV. The functional mechanism of miR‐874 in I/R injury was explored when miR‐874 and the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway were inhibited. Terminal deoxynucleotidyl transferase (TdT)‐mediated dUTP biotin nick‐end labeling (TUNEL) staining was used to detect cardiomyocyte apoptosis and dual luciferase reporter gene assay to identify the targeting relationship between miR‐874 and STAT3. Expression of the JAK2/STAT3 signaling pathway and apoptosis‐related genes was determined. Initially, upregulated miR‐874 was observed in I/R mice. Then, miR‐874 inhibition improved cardiac function of I/R mice, inhibited cardiomyocyte apoptosis (also shown as decreased Bcl‐2 associated X protein B [Bax] and increased B‐cell lymphoma‐2 [Bcl‐2]), and activated the JAK2/STAT3 signaling pathway. STAT3, a target gene of miR‐874, was upregulated following miR‐874 inhibition. Finally, we also observed that the effect of miR‐874 was lost when the JAK2/STAT3 signaling pathway was blocked. The findings indicate miR‐874 as a contributory role in cardiac I/R injury, with miR‐874 inhibition alleviating cardiac I/R injury in mice following SEV pretreatment by targeting STAT3 through the JAK2/STAT3 signaling pathway. The findings indicate microRNA (miR)‐874 as a contributory role in cardiac ischemia–reperfusion injury (I/R) injury, with miR‐874 inhibition alleviating cardiac I/R injury in mice following sevoflurane pretreatment by targeting signal transducer and activator of transcription 3 (STAT3) through the Janus kinase 2 (JAK2)/STAT3 signaling pathway. [ABSTRACT FROM AUTHOR]

Lithium metal anodes suffer from poor cycling stability and potential safety hazards. To alleviate these problems, Li thin‐film anodes prepared on current collectors (CCs) and Li‐free types of anodes that involve direct Li plating on CCs have received increasing attention. In this study, the atomic‐scale design of Cu‐CC surface lithiophilicity based on surface lattice matching of the bcc Li(110) and fcc Cu(100) faces as well as electrochemical achievement of Cu(100)‐preferred surfaces for smooth Li deposition with a low nucleation barrier is reported. Additionally, a purposely designed solid–electrolyte interphase is created for Li anodes prepared on CCs. Not only is a smooth planar Li thin film prepared, but a uniform Li plating/stripping on the skeleton of 3D CCs is achieved as well by high utilization of the surface and cavities of the 3D CCs. This work demonstrates surface electrochemistry approaches to construct stable Li metal–electrolyte interphases towards practical applications of Li anodes prepared on CCs. Get in touch with lithium: The generation of surface lithiophilicity on planar and 3D Cu hosts for Li metal anodes is reported. Enabled by a lattice matching of Cu(100) and Li(110), smooth deposition of Li thin films and the creation of ultra‐smooth ultra‐thin SEI on the Cu hosts is made possible. This allows a high utilization of not only the surface but also cavities of the Cu hosts. [ABSTRACT FROM AUTHOR]

Lithium metal anodes suffer from poor cycling stability and potential safety hazards. To alleviate these problems, Li thin‐film anodes prepared on current collectors (CCs) and Li‐free types of anodes that involve direct Li plating on CCs have received increasing attention. In this study, the atomic‐scale design of Cu‐CC surface lithiophilicity based on surface lattice matching of the bcc Li(110) and fcc Cu(100) faces as well as electrochemical achievement of Cu(100)‐preferred surfaces for smooth Li deposition with a low nucleation barrier is reported. Additionally, a purposely designed solid–electrolyte interphase is created for Li anodes prepared on CCs. Not only is a smooth planar Li thin film prepared, but a uniform Li plating/stripping on the skeleton of 3D CCs is achieved as well by high utilization of the surface and cavities of the 3D CCs. This work demonstrates surface electrochemistry approaches to construct stable Li metal–electrolyte interphases towards practical applications of Li anodes prepared on CCs. [ABSTRACT FROM AUTHOR]

A newly designed electron donor-acceptor conjugate consisting of an endohedral dimetallofullerene (La2@ Ih-C80) and phenoxazine (POZ) was successfully synthesized under Prato conditions. Our results document that the 1,3-dipolar cycloaddition took place across the [5,6] junction to afford exclusively the corresponding [5,6] cycloadduct. The structure of the conjugate was characterized by means of NMR spectroscopy, absorption spectroscopy, and electrochemical studies. Computational calculations suggest that the electron density of the highest occupied molecular orbital (HOMO) is distributed on the POZ moiety, whereas that of the lowest unoccupied molecular orbital (LUMO) is located at the endohedral La atoms, leading to efficient separation of the HOMO and LUMO in the conjugate. Time-resolved absorption spectroscopic investigations and spectroelectrochemical measurements corroborate the formation of the energetically low-lying (La2@ Ih-C80).−-(POZ).+ radical-ion-pair state by means of ultrafast through-space electron transfer. [ABSTRACT FROM AUTHOR]

Bis(sulfane)carbon(0) (BSC; Ph2S→C←SPh2 ( 1)) is successfully synthesized by deprotonation of the corresponding protonated salt 1⋅HTfO. The diprotonated salt 1⋅(HTfO)2 as the starting material can be also easily accessed by the deimination of iminosulfane(sulfane)carbon(0) (iSSC) ⋅HBF4. Density functional theory calculations revealed the peculiar electronic structure of 1, which has two lone pairs of electrons at the central carbon atom. The largest proton affinities (PA(1): 297.5 kcal mol−1; PA(2): 183.7 kcal mol−1) and the highest energy levels of the HOMOs (HOMO: −4.89 eV; HOMO−1: −5.02 eV) for 1 among the two-sulfur-stabilized carbones clearly indicate the strong donor ability of carbon center stabilized by two SII ligands. The donating ability of these lone pairs of electrons is demonstrated by the C-diaurated and C-proton-aurated complexes, which provide the first experimental evidence for two-sulfurstabilized carbones behaving as four-electron donors. Furthermore, the syntheses and application of AgI carbone complexes as carbone transfer agents are also reported. [ABSTRACT FROM AUTHOR]

The thermal stability of oxidized single-walled carbon nanotubes (SWNTs) with various degrees of oxidation was investigated. The oxidized SWNTs exhibited lower absorption and radial breathing mode (RBM) peaks and a higher intensity ratio of the D band to the G band (D/G) in their absorption and Raman spectra than those of the pristine SWNTs. After the thermal treatment, the D/G ratio of the oxidized SWNTs almost recovered its original intensity, regardless of the degree of oxidation. The absorption, photoluminescence (PL), and RBM peaks could not recover their original intensities when the oxidation degree was high. The results indicate that the elimination and decomposition reactions proceeded competitively depending on the degree of oxidation. In addition, a new PL peak was observed in the near-infrared region, and the PL peak intensity increased with the subsequent thermal treatment. The theoretical calculations provided an insight into the possible pathways for the decomposition of oxidized SWNTs, showing that the O2 elimination and CO/CO2 evolution proceed competitively during thermal treatment. [ABSTRACT FROM AUTHOR]

Bis-silylated and bis-germylated derivatives of Lu3N@ Ih-C80 ( 3, 4, 5) were successfully synthesized by the photochemical addition of disiliranes 1 a, 1 b or digermirane 2, and fully characterized by spectroscopic, electrochemical, and theoretical studies. Interestingly, digermirane 2 reacts more efficiently than disiliranes 1 a and 1 b because of its good electron-donor properties and lower steric hindrance around the GeGe bond. The 1,4-adduct structures of 3, 4, 5 were unequivocally established by single-crystal X-ray crystallographic analyses. The electrochemical and theoretical studies reveal that the energy gaps between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the 1,4-adducts are remarkably smaller than those of Lu3N@ Ih-C80, because the electron-donating groups effectively raise the HOMO levels. It is also observed that germyl groups are slightly more electron-donating than the silyl groups on the basis of the redox properties and the HOMO-LUMO energies of 4 and 5. Bis-silylation and bis-germylation are effective and versatile methods for tuning the electronic characteristics of endohedral metallofullerenes. [ABSTRACT FROM AUTHOR]

Hydrogen sulphide ( H2S), one of three signalling gasotransmitters, plays an important role in oxidative stress and apoptosis. However, the effects of H2S on oxidative stress-induced apoptosis in focal cerebral ischaemic injury in rats have not been clarified., In the present study, sodium hydrosulphide ( NaHS) was used as the H2S donor. Eighty-four Sprague- Dawley rats were randomly divided into six groups: sham, sham + low-dose (2.8 mg/kg) NaHS, sham + high-dose (11.2 mg/kg) NaHS, infarct, infarct + low-dose NaHS and infarct + high-dose NaHS. The focal cerebral ischaemic model was created by cranially inserting a nylon thread with a rounded tip into an internal carotid artery. Rats were killed 21 h after administration of NaHS., In the infarct + low-dose NaHS compared with infarct group, infarct volume was significantly decreased and injury to the mitochondria in nerve cells was mitigated. Furthermore, significant increases were seen in mitochondrial superoxide dismutase and glutathione peroxidase activity and neuronal bcl-2 protein levels, whereas mitochondrial malondialdehyde content and neuronal bax and caspase 3 protein levels were significantly decreased, in the infarct + low-dose NaHS compared with infarct group. The effects seen in the infarct group were significantly aggravated in the infarct + high-dose NaHS group., The findings of the present study provide novel evidence for the dual effects of H2S on focal cerebral ischaemic injury via modulation of oxidative stress-induced apoptosis. [ABSTRACT FROM AUTHOR]

The cover page of the 2014 issue of the journal "Angewandte Chemie," International Edition is presented.

The cover picture shows the molecular structure of a La2@Ih‐C80–phenoxazine conjugate and its differential absorption spectra observed upon femtosecond flash photolysis in tetrahydrofuran. Spectroscopic investigations corroborate the formation of the energetically low‐lying radical‐ion‐pair‐state by means of ultrafast through‐space electron transfer. Details are given in the Full Paper by Takeshi Akasaka, Dirk M. Guldi and co‐workers on page 1067 in Issue 7, 2017 (DOI: 10.1002/cplu.201600391). [ABSTRACT FROM AUTHOR]

Two‐sulfur‐stabilized carbones: the presence of a “second” lone pair on a coordinated atom significantly enhances the electron‐donating ability of the central carbon in carbones. The strongest electron‐donating ability of bis(sulfane)carbon(0) (BSC) among the two‐sulfur‐stabilized carbones was demonstrated by the generation of diprotonated salt BSC⋅H2+. The C‐digold(I) complexes of two‐sulfur‐stabilized carbones provide the first experimental proof of their four‐electron‐donating ability. More information can be found in the Full Paper by T. Fujii et al. on page 8694. [ABSTRACT FROM AUTHOR]

Invited for the cover of this issue are the groups of M. Kako (The University of Electro-Communications, Japan), M. M. Olmstead (University of California, USA), A. L. Balch (University of California, USA), S. Nagase (Kyoto University, Japan), T. Akasaka (University of Tsukuba, Japan). The image depicts the 1,4-bis-silylated and 1,4-bis-germylated structures of Lu3N@ I h -C80, which represent rare examples of the crystallographic studies of functionalized Lu3N@ I h -C80. Read the full text of the article at . [ABSTRACT FROM AUTHOR]

The article presents cover page of the journal featuring a diagram related to an article on structural determination and characterization of electronic properties of bis-silylated compound by M. Kako and colleagues.