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1.
ACS Appl Mater Interfaces ; 13(6): 7355-7369, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33534550

RESUMO

Ni-rich high-energy-density lithium ion batteries pose great risks to safety due to internal short circuits and overcharging; they also have poor performance because of cation mixing and disordering problems. For Ni-rich layered cathodes, these factors cause gas evolution, the formation of side products, and life cycle decay. In this study, a new cathode electrolyte interphase (CEI) for Ni2+ self-oxidation is developed. By using a branched oligomer electrode additive, the new CEI is formed and prevents the reduction of Ni3+ to Ni2+ on the surface of Ni-rich layered cathode; this maintains the layered structure and the cation mixing during cycling. In addition, this new CEI ensures the stability of Ni4+ that is formed at 100% state of charge in the crystal lattice at high temperature (660 K); this prevents the rock-salt formation and the over-reduction of Ni4+ to Ni2+. These findings are obtained using in situ X-ray absorption spectroscopy, operando X-ray diffraction, operando gas chromatography-mass spectroscopy, and X-ray photoelectron spectroscopy. Transmission electron microscopy reveals that the new CEI has an elliptical shape on the material surface, which is approximately 100 nm in length and 50 nm in width, and covers selected particle surfaces. After the new CEI was formed on the surface, the Ni2+ self-oxidation gradually affects from the surface to the bulk of the material. It found that the bond energy and bond length of the Ni-O are stabilized, which dramatically inhibit gas evolution. The new CEI is successfully applied in a Ni-rich layered compound, and the 18650- and the punch-type full cells are fabricated. The energy density of the designed cells is up to 300 Wh/kg. Internal short circuit and overcharging safety tests are passed when using the standard regulations of commercial evaluation. This new CEI technology is ready and planned for future applications in electric vehicle and energy storage.

2.
ACS Appl Mater Interfaces ; 13(5): 6156-6167, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33507065

RESUMO

Li-CO2 batteries have recently attracted attention as promising candidates for next-generation energy storage devices due to their extremely high theoretical energy density. The real application of Li-CO2 cells involves addressing several drawbacks, including high charging potential, poor coulombic efficiency, and low rechargeability. Molybdenum disulfide supported on carbon nanotubes (MoS2/CNT) with various ratios functioned as a cathode catalyst for Li-CO2 batteries. The optimal MoS2/CNT composite achieved a maximum discharge capacity of 8551 mAh g-1 with a coulombic efficiency of 96.7%. This hybrid also obtained an initial charging plateau of 3.87 V at a current density of 100 mA g-1 with a cutoff capacity of 500 mAh g-1. It provided ideal electrochemical stability of 142 cycles at the current densities of 100 mA g-1, which was comparable with that of some precious metal catalysts. This optimized MoS2/CNT was also cycled at 200 and 400 mA g-1 for 112 and 55 times, respectively. Density functional theory calculations demonstrated that the sulfided Mo-edge (s-Mo-edge) on MoS2 materials showed appropriate adsorption strengths of Li, CO2, and Li2CO3. Moreover, joint results of Raman profiles and extended X-ray absorption fine structure spectra elucidated that the catalytic efficiencies of MoS2/CNT hybrids were proportional to the quantities of exposed s-Mo-edge active sites.

3.
ACS Appl Mater Interfaces ; 12(15): 17353-17363, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32202752

RESUMO

Li-CO2 batteries are of great interest among researchers due to their high energy density and utilization of the greenhouse gas CO2 to produce energy. However, several shortcomings have been encountered in the practical applications of Li-CO2 batteries, among which their poor cyclability and high charge overpotential necessary to decompose the highly insulating discharge product (Li2CO3) are the most important. Herein, the spinel zinc cobalt oxide porous nanorods with carbon nanotubes (ZnCo2O4@CNTs) composite is employed as a cathode material in Li-CO2 batteries to improve the latter's cycling performance. The ZnCo2O4@CNT cathode-based Li-CO2 battery exhibited a full discharge capacity of 4275 mAh g-1 and excellent cycling performance over 200 cycles with a charge overpotential below 4.3 V when operated at a current density of 100 mA g-1 and fixed capacity of 500 mAh g-1. The superior performance of the ZnCo2O4@CNT cathode composite was attributed to the synergistic effects of ZnCo2O4 and CNT. The highly porous ZnCo2O4 nanorod structures in the ZnCo2O4@CNT catalyst showed enhanced catalytic activity/stability, which effectively promoted CO2 diffusion during the discharging process and accelerated Li2CO3 decomposition at a low charge overpotential.

4.
ACS Appl Mater Interfaces ; 11(43): 39827-39840, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31597424

RESUMO

Self-terminated oligomer additives synthesized from bismaleimide and barbituric acid derivatives improve the safety and performance of lithium-ion batteries (LIBs). This study investigates the interface interaction of these additives and the cathode material. Two additives were synthesized by Michael addition (additive A) and aza-Michael addition (additive B). The electrochemical performances of bare and modified LiNi0.6Mn0.2Co0.2O2 (NMC622) materials are studied. The cycling stability and rate capability of NMC622 considerably improve on surface modification with additive B. According to the differential scanning calorimetry results, the exothermic heat of fully deliathiated NMC622 is dramatically decreased through surface modification with both additives. The electrode surface kinetics and interface interaction phenomena of the additives are determined through surface plasma resonance measurements in operando gas chromatography-mass spectroscopy (GCMS) and in situ soft X-ray absorption spectroscopy (XAS). The binding rate constant of additive B onto NMC622 particles is 1.2-2.3 × 104 M-1 s-1 in the temperature range of 299-311 K, which is ascribed to the strong binding affinity toward the electrode surface. This affinity enhances Li+ diffusion, which allows the electrode modified by additive B to provide high electrochemical performance with superior thermal stability. In operando GCMS reveals that gas evolution due to the electrolyte degradation at the NMC622 surface contributes to safety hazards in the bare NMC622 material. In situ soft XAS indicates the occurrence of structural transformation in the bare NMC622 material after it is fully charged and at elevated temperatures. The NMC622 material is stabilized by incorporating additives. The unique performance of additive B can be attributed to its linear structure that allows superior electrode surface adhesion compared with that of additive A. Therefore, this study presents an optimized working principle of self-terminated oligomers, which can be developed and applied to improve the safety and performance of LIBs.

5.
Yi Chuan ; 40(12): 1112-1119, 2018 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-30559100

RESUMO

Clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) system is the third-generation genome editing tools that was developed and widely used in recent years. However, Streptococcus pyogenes Cas9 (SpCas9) in this system could only recognize NGG PAM (protospacer adjacent motif), which largely restricts the range of genome editing. The VQR (D1135V/R1335Q/T1337R) variant of SpCas9 could recognize NGAA, NGAG and NGAT PAMs in rice. However, whether VQR variant could recognize NGAC PAM remains unclear. In this study, three low editing efficiency sites of the VQR variant, NAL1-Q1, NAL1-Q2 and LPA1-Q, were selected for genome editing using the improved CRISPR/VQR system. The improved CRISPR/VQR system effectively edited these target sites, and the gene editing efficiency was 9.75%, 43.90% and 29.26% respectively. To ensure the recognition of NGAC PAM by the improved CRISPR/VQR system, two NGAC PAM containing sites (NAL-C and GL1-C) in the NARROW LEAF 1 (NAL1) for leaf length and GLOSSY1 (GL1) genes for wax biosynthesis were selected for genome editing in rice in this study, and 57 transgenic plants were obtained. The PCR amplification and sequencing results showed that 27 plants (47.36%) had mutation in the NAL1-C site, 44 plants (77.19%) had mutation in the GL1 gene, and 26 plants (45.61%) had mutation in the NAL-C and GL1-C sites. Further analysis revealed that there were four types of mutations caused by the CRISPR/VQR system, respectively for the hybrid mutation, biallelic mutation, chimeric mutation and homozygous mutations. Among them, heterozygous mutation and biallelic mutation were dominant changes. These results indicated that the improved CRISPR/VQR system could efficiently edit the NGAC PAM sites of the rice and produce abundant mutant types. This study provides a theoretical basis for NGAC PAM editing in rice and other related plants.


Assuntos
Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas , Edição de Genes , Oryza/genética
6.
Eur J Cancer Prev ; 24(6): 508-16, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25642791

RESUMO

This meta-analysis was conducted to assess the association between fruit and vegetable intake and bladder cancer risk. Eligible studies published up to August 2014 were retrieved both through a computer search of PubMed, Embase and the Cochrane library and through a manual review of references. The summary relative risks with 95% confidence intervals (CIs) for the highest versus the lowest intakes of fruits and vegetables were calculated with random-effects models. Heterogeneity and publication bias were also evaluated. Potential sources of heterogeneity were detected with metaregression. Subgroup analyses and sensitivity analyses were also performed. A total of 27 studies (12 cohort and 15 case-control studies) were included in this meta-analysis. The summary relative risks for the highest versus lowest were 0.84 (95% CI: 0.72-0.96) for vegetable intake and 0.81 (95% CI: 0.73-0.89) for fruit intake. The dose-response analysis showed that the risk of bladder cancer decreased by 8% (relative risk=0.92; 95% CI: 0.87-0.97) and 9% (relative risk=0.91; 95% CI: 0.83-0.99) for every 200 g/day increment in vegetable and fruit consumption, respectively. Sensitivity analysis confirmed the stability of the results. Our findings suggest that intake of vegetables and fruits may significantly reduce the risk of bladder cancer. Further well-designed prospective studies are warranted to confirm these findings.


Assuntos
Dieta , Frutas , Neoplasias da Bexiga Urinária/prevenção & controle , Verduras , Comportamento Alimentar , Humanos , Estudos Observacionais como Assunto
7.
Nutr Cancer ; 67(3): 392-400, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25706900

RESUMO

This meta-analysis was conducted to assess the association between coffee consumption and prostate cancer risk. Thirteen cohort studies with 34,105 cases and 539,577 participants were included in the meta-analysis. The summary relative risks (RRs) with 95% confidence intervals (CIs) for different coffee intake levels were calculated. Dose-response relationship was assessed using generalized least square trend estimation. The pooled RR for the highest vs. lowest coffee intake was 0.90 (95% CI: 0.85-0.95), with no significant heterogeneity across studies (P = 0.267; I(2) = 17.5%). The dose-response analysis showed a lower cancer risk decreased by 2.5% (RR = 0.975; 95% CI: 0.957-0.995) for every 2 cups/day increment in coffee consumption. Stratifying by geographic region, there was a statistically significant protective influence of coffee on prostate cancer risk among European populations. In subgroup analysis of prostate cancer grade, the summary RRs were 0.89 (95% CI: 0.83-0.96) for nonadvanced, 0.82 (95% CI: 0.61-1.10) for advanced and 0.76 (95% CI: 0.55-1.06) for fatal diseases. Our findings suggest that coffee consumption may be associated with a reduced risk of prostate cancer and it also has an inverse association with nonadvanced prostate cancer. Because of the limited number of studies, more prospective studies with large sample size are needed to confirm this association.


Assuntos
Café , Neoplasias da Próstata/prevenção & controle , Estudos de Coortes , Humanos , Masculino , Neoplasias da Próstata/etiologia , Viés de Publicação , Risco
8.
World J Gastroenterol ; 20(40): 14821-30, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25356042

RESUMO

Glucagon-like peptide1 (GLP-1) is secreted from Langerhans cells in response to oral nutrient intake. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are a new class of incretin-based anti-diabetic drugs. They function to stimulate insulin secretion while suppressing glucagon secretion. GLP-1-based therapies are now well established in the management of type 2 diabetes mellitus (T2DM), and recent literature has suggested potential applications of these drugs in the treatment of obesity and for protection against cardiovascular and neurological diseases. As we know, along with change in lifestyles, the prevalence of non-alcoholic fatty liver disease (NAFLD) in China is rising more than that of viral hepatitis and alcoholic fatty liver disease, and NAFLD has become the most common chronic liver disease in recent years. Recent studies further suggest that GLP-1RAs can reduce transaminase levels to improve NAFLD by improving blood lipid levels, cutting down the fat content to promote fat redistribution, directly decreasing fatty degeneration of the liver, reducing the degree of liver fibrosis and improving inflammation. This review shows the NAFLD-associated effects of GLP-1RAs in animal models and in patients with T2DM or obesity who are participants in clinical trials.


Assuntos
Anti-Inflamatórios/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hepatite/tratamento farmacológico , Incretinas/uso terapêutico , Fígado/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade/tratamento farmacológico , Receptores de Glucagon/agonistas , Animais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Receptor do Peptídeo Semelhante ao Glucagon 1 , Hepatite/sangue , Hepatite/diagnóstico , Hepatite/epidemiologia , Humanos , Lipídeos/sangue , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Cirrose Hepática/prevenção & controle , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Obesidade/sangue , Obesidade/diagnóstico , Obesidade/epidemiologia , Receptores de Glucagon/metabolismo , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
9.
Lipids Health Dis ; 13: 113, 2014 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-25015267

RESUMO

BACKGROUND: Body adiposity, especially ectopic fat accumulation, has a range of metabolic and cardiovascular effects. The aim of this study was to investigate the association between head fat and metabolic values in Chinese obese patients. METHODS: Data of this cross-sectional study from 66 obese patients were collected. Fat distribution was measured by dual-energy X-ray absorptiometry, and data of body weight, body mass index (BMI), neck circumference (NC), waist circumference (WC), hip circumference (HC), visceral index, basal metabolism (BM), glucose metabolism, lipid levels, uric acid (UA) had been collected. RESULTS: 1) Head fat was significantly associated with BMI, WC, HC, visceral index, BM, total fat and total fat excluding head fat in both males and females (p<0.05). Head fat was positively correlated with upper limb fat, trunk fat, weight, fasting plasma C peptide, fasting plasma insulin and UA in women(p<0.05), and the association was not statistically significant in male (p>0.05). Head fat was positively corrected with NC in males (p<0.05) but not females (p>0.05). There was no significant correlation between head fat and fasting plasma glucose, total choleslerolemia, triglyceridemia, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and free fat acid in either gender (p>0.05). 2) Receiver operating characteristic analysis showed that a head fat of 1925.6 g and a head fat of 1567.85 g were the best cut-off values to determine subjects with low high-density lipoprotein cholesterol and hyperuricemia respectively. CONCLUSIONS: Head fat accumulation was closely associated with increased body fat, hyperinsulinemia, hyperuricemia, and impared lipid profile, suggesting it might be used as an indicator for dyslipidemia and hyperuricemia.


Assuntos
Adiposidade , Obesidade/patologia , Adulto , Área Sob a Curva , Glicemia , Feminino , Cabeça/patologia , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/etiologia , Hiperlipidemias/patologia , Hiperuricemia/sangue , Hiperuricemia/etiologia , Hiperuricemia/patologia , Metabolismo dos Lipídeos , Masculino , Obesidade/sangue , Obesidade/complicações , Curva ROC , Gordura Subcutânea/patologia , Adulto Jovem
10.
Int J Clin Exp Med ; 7(11): 3954-63, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25550903

RESUMO

Previous studies have investigated the relationship between oral contraceptives (OCs) use and kidney cancer risk. However, they yielded inconsistent results. To our knowledge, a comprehensive assessment of the association between OC and kidney cancer risk has not been reported. Hence, we conducted a meta-analysis to quantify the association. We identified all relevant studies up to July 2014 through a literature search of using PubMed and EMBASE, and by reviewing the references from the retrieved articles. Fixed-effect and random-effect models were used to estimate summary relative risks (SRRs) and the corresponding 95% confidence intervals (CIs). A total of 12 studies were eligible and included in this meta-analysis, involving 4,206 kidney cancer cases and 638,677 participants. The SRR of kidney cancer for ever versus never OC use was 0.89 (95% CI: 0.82-0.98). The protection became stronger when compared the longest duration of OC use with never use (RR = 0.80; 95% CI: 0.68-0.94). In dose-response analysis, we found that the kidney cancer risk decreased by 2% for per 1 year increment in OC use (RR = 0.98; 95% CI: 0.96-0.99). No apparent heterogeneity was observed across studies included in this analysis. Egger's and Begg's test also indicated no publication bias. The present study suggested that OC may reduce the risk of kidney cancer, especially for long-term users. More well-conducted and large-scale prospective studies are warranted to confirm the effects of OC use on kidney cancer.

11.
Chin J Cancer ; 29(2): 212-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20109354

RESUMO

BACKGROUND AND OBJECTIVE: Primary renal synovial sarcoma is rare and might be misdiagnosed as another renal tumor. This study demonstrates the clinicopathologic and immunohistochemical features, differential diagnosis, and prognosis of such tumors. METHODS: Histologic slides and clinical data were reviewed for 4 patients with primary renal synovial sarcoma and immunohistochemical staining was performed. Molecular analysis was performed on 2 cases to demonstrate the presence of the SYT-SSX gene fusion transcripts by reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: The patients were 2 women and 2 men aged from 32 to 48 years. The tumors were 10.0-15.0 cm in diameter, grey-white and solid, and hemorrhage or necrosis was observed. Microscopically, the tumors consisted of mitotically active, monomorphic plump spindle cells with indistinct cell borders growing in short, intersecting fascicles. Hypocellular myxoid areas and a prominent hemangiopericytomatous pattern were present in all cases. The average mitotic rate was 5-8 mitoses/10 high-power fields. Hemorrhage and tumor necrosis were easily found. Scattered small cysts lined with flat, cuboidal, or hobnailed epithelia were found in 3 cases. Tumor cells are immunoreactive for Vimentin (4/4), Bcl-2 (4/4), CD99 (4/4), and CD56 (3/4), and focally for EMA (3/4) and Cytokeratin (3/4). SYT-SSX1 gene fusion was detected in the 2 cases in which RT-PCR analysis was performed. One patient had tumor metastasis to the lung 6 months after surgery and died 5 months later. Multiple metastasis to the liver occurred in one patient and the patient died 13 months after the initial surgery. The other 2 patients had tumors recur at 8 and 15 months and died at 18 and 21 months, respectively, after the initial operation. CONCLUSION: Primary renal synovial sarcoma is rare, with poor prognosis, characterized by SYT-SSX gene fusion, and needs to be differentiated from other renal sarcomas.


Assuntos
Neoplasias Renais/cirurgia , Nefrectomia , Proteínas de Fusão Oncogênica/metabolismo , Sarcoma Sinovial/cirurgia , Antígeno 12E7 , Adulto , Antígenos CD/metabolismo , Antígeno CD56/metabolismo , Moléculas de Adesão Celular/metabolismo , Feminino , Seguimentos , Humanos , Queratinas/metabolismo , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Mucina-1/metabolismo , Recidiva Local de Neoplasia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sarcoma Sinovial/metabolismo , Sarcoma Sinovial/patologia , Sarcoma Sinovial/secundário , Taxa de Sobrevida , Vimentina/metabolismo
12.
Yi Chuan Xue Bao ; 32(10): 1082-8, 2005 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16252704

RESUMO

Using an estrogen-inducible expression XVE (LexA-VP16-Estragon Receptor) system, we have generated approximately 40 000 independent T-DNA insertion lines of Arabidopsis thaliana. Segregation analyses of about 18000 lines indicated that 51.6% of them contain single T-DNA insertions and that the average insertion number is 1.38 copies per line. Mutants displaying a variety of morphological alterations were identified, including those that affect development of roots,hypocotyls, leaves, floral organs and seeds as well as the flowering time.


Assuntos
Arabidopsis/genética , DNA Bacteriano/genética , Mutagênese Insercional/métodos , Plantas Geneticamente Modificadas/genética , Arabidopsis/anatomia & histologia , Arabidopsis/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Clonagem Molecular , Estrogênios/farmacologia , Vetores Genéticos/genética , Proteína Vmw65 do Vírus do Herpes Simples/genética , Mutagênese Insercional/efeitos dos fármacos , Fenótipo , Plantas Geneticamente Modificadas/anatomia & histologia , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plasmídeos/genética , Receptores de Estrogênio/genética , Serina Endopeptidases/genética , Ativação Transcricional/efeitos dos fármacos
13.
Yi Chuan ; 26(3): 403-8, 2004 May.
Artigo em Chinês | MEDLINE | ID: mdl-15640029

RESUMO

Transcription factors play important roles in the regulation of plant growth and development, as well as its response to environment. A typical higher plant transcription factor usually contains a DNA-binding domain, a transcription regulation domain, oligomerization site and a nuclear localization domain. Transcription factors interact with cis-elements and regulate the expression of target genes through these domains. Recent studies show that transcription factors are efficient new molecular tools for the manipulation of plant growth and development. In this review, we will summarize the current knowledge in the study of higher plant transcription factor, with emphasis on the regulation of transcription factor on higher plant development and morphogenesis, as well as the application of transcription factor in plant improvement.


Assuntos
Genes de Plantas/genética , Proteínas de Domínio MADS/genética , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição de Choque Térmico , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Proteínas de Domínio MADS/metabolismo , Proteínas de Domínio MADS/fisiologia , Mutação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia , Transcrição Gênica
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