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1.
ChemSusChem ; 15(1): e202102368, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34766733

RESUMO

Cerium (IV)-based metal-organic frameworks (MOFs) are highly desirable due to their unique potential in fields such as redox catalysis and photocatalysis. However, due to the high reduction potential of CeIV species in solution, it is still a great challenge to synthesize CeIV -MOFs with novel structures, which are extremely dominated by the hexanuclear Ce-O cluster inorganic building units (IBUs). Herein, a Ce-O IBU chain containing CeIV -MOF, CSUST-3 (CSUST: Changsha University of Science and Technology), was successfully prepared using the kinetic stabilization study of UiO-66(Ce)-NDC (H2 NDC=2,6-naphthalenedicarboxylic acid). Furthermore, owing to the superior redox activity, Lewis acidity and semiconductor-like behavior owing to Ce4+ , activated CSUST-3 was demonstrated to be an excellent catalyst for CO2 chemical fixation. One-pot synthesis of styrene carbonate from styrene and CO2 was achieved under mild conditions (1 atm CO2 , 80 °C, and solvent free). Moreover, activated CSUST-3 was shown to be a remarkable co-catalyst-free photocatalyst for overall water splitting (OWS), rendering 59 µmol g-1 h-1 of H2 and 22 µmol g-1 h-1 of O2 under simulated sunlight irradiation (Na2 S-Na2 SO3 as sacrificial agent).

2.
ACS Appl Mater Interfaces ; 13(3): 3899-3910, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33438995

RESUMO

Mixed-valence metal-organic frameworks (MOFs) have exhibited unique potential in fields such as catalysis and gas separation. However, it is still an open challenge to prepare mixed-valence MOFs with isolated Ce(IV, III) arrays due to the easy formation of CeIII under the synthetic conditions for MOFs. Meanwhile, the performance of Li-S batteries is greatly limited by the fatal shuttle effect and the slow transmission rate of Li+ caused by the inherent characteristics of sulfur species. Here, we report a mixed-valence cerium MOF, named CSUST-1 (CSUST stands for Changsha University of Science and Technology), with isolated Ce(IV, III) arrays and abundant oxygen vacancies (OVs), synthesized as guided by the facile and elaborate kinetic stability study of UiO-66(Ce), to work as an efficient separator coating for circumventing both issues at the same time. Benefiting from the synergistic function of the Ce(IV, III) arrays (redox couples), the abundant OVs, and the open Ce sites within CSUST-1, the CSUST-1/CNT composite, as a separator coating material in the Li-S battery, can remarkably accelerate the redox kinetics of the polysulfides and the Li+ transportation. Consequently, the Li-S cell with the CSUST-1/CNT-coated separator exhibited a high initial specific capacity of 1468 mA h/g at 0.1 C and maintained long-term stability for a capacity of 538 mA h/g after 1200 cycles at 2 C with a decay rate of only 0.037% per cycle. Even at a high sulfur loading of 8 mg/cm2, the cell with the CSUST/CNT-coated separator still demonstrated excellent performance with an initial areal capacity of 8.7 mA h/cm2 at 0.1 C and retained the areal capacity of 6.1 mA h/cm2 after 60 cycles.

3.
J Comput Biol ; 25(8): 907-916, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29957033

RESUMO

To identify signature genes for the pathogenesis of cancer, which provides a theoretical support for prevention and early diagnosis of cancer. The pattern recognition method was used to analyze the genome-wide gene expression data, which was collected from the The Cancer Genome Atlas (TCGA) database. For the transcription of invasive breast carcinoma, lung adenocarcinoma, lung squamous cell carcinoma, colon adenocarcinoma, renal clear-cell carcinoma, thyroid carcinoma, and hepatocellular carcinoma of the seven cancers, the signature genes were selected by means of a combination of statistical methods, such as correlation, t-test, confidence interval, etc. Modeling by artificial neural network model, the accuracy can be as high as 98% for the TCGA data and as high as 92% for the Gene Expression Omnibus (GEO) independent data, the recognition accuracy of stage I is more than 95%, which is higher compared with the previous study. The common genes emerging in five cancers were obtained from the signature genes of seven cancers, PID1, and SPTBN2. At the same time, we obtain three common pathways of cancer by using Kyoto Encyclopedia of Genes and Genomes' pathway analysis. A functional analysis of the pathways shows their close relationship at the level of gene regulation, which indicted that the identified signature genes play an important role in the pathogenesis of cancer and is very important for understanding the pathogenesis of cancer and the early diagnosis.


Assuntos
Biomarcadores Tumorais/genética , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias/epidemiologia , Neoplasias/genética , Reconhecimento Automatizado de Padrão , Humanos , Neoplasias/diagnóstico
4.
Virus Res ; 128(1-2): 58-64, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17499380

RESUMO

In the early 1970s, the Chinese Equine Infectious Anemia Virus (EIAV) vaccine, EIAV(DLA), was developed through successive passages of a wild-type virulent virus (EIAV(L)) in donkeys in vivo and then in donkey macrophages in vitro. EIAV attenuation and cell tropism adaptation are associated with changes in both envelope and long terminal repeat (LTR). However, specific LTR changes during Chinese EIAV attenuation have not been demonstrated. In this study, we compared LTR sequences from both virulent and attenuated EIAV strains and documented the diversities of LTR sequence from in vivo and in vitro infections. We found that EIAV LTRs of virulent strains were homologous, while EIAV vaccine have variable LTRs. Interestingly, experimental inoculation of EIAV(DLA) into a horse resulted in a restriction of the LTR variation. Furthermore, LTRs from EIAV(DLA) showed higher Tat transactivated activity than LTRs from virulent strains. By using chimeric clones of wild-type LTR and vaccine LTR, the main difference of activity was mapped to the changes of R region, rather than U3 region.


Assuntos
Variação Genética , Cavalos/virologia , Vírus da Anemia Infecciosa Equina/patogenicidade , Macrófagos/virologia , Monócitos/virologia , Regiões Promotoras Genéticas , Sequências Repetidas Terminais/genética , Animais , Sequência de Bases , Células Cultivadas , Equidae , Anemia Infecciosa Equina/fisiopatologia , Anemia Infecciosa Equina/virologia , Regulação Viral da Expressão Gênica , Genes tat , Doenças dos Cavalos/fisiopatologia , Doenças dos Cavalos/virologia , Vírus da Anemia Infecciosa Equina/genética , Vírus da Anemia Infecciosa Equina/metabolismo , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Sequências Repetidas Terminais/fisiologia , Ativação Transcricional , Vacinas Virais
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