Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Opt Lett ; 48(2): 295-298, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36638441

RESUMO

Ytterbium (Yb)-ions-doped sesquioxide crystal is an attractive gain medium for a tunable and pulsed laser owing to its high thermal conductivity. In particular, it has been identified that Yb:LuScO3 has the largest energy storage property compared with other sesquioxide crystals, which is favorable for passive Q switching. In this Letter, continuous wave (CW) and the first, to the best of our knowledge, passively Q switched laser operations were demonstrated with a Yb:LuScO3 crystal. For CW laser operation, it generated the maximum output power of 8.68 W, corresponding to a slope efficiency up to 78.3%. Using Cr:YAG crystals as saturable absorbers, stable passive Q switching lasers were obtained with the Yb:LuScO3 crystal. Both the CW and Q switched lasers operate on the strongest fluorescence emission peak of 1038 nm. With Cr:YAG as the saturable absorber, efficient passively Q switched lasers with a slope efficiency of 45% were obtained with the pulse width, pulse energy, and peak power of 5.9 ns, 116 µJ, and 18.5 kW, respectively.

2.
Cardiol Young ; 28(9): 1106-1114, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29978770

RESUMO

BACKGROUND: We previously reported four heterozygous missense mutations of MYH7, KCNQ1, MYLK2, and TMEM70 in a single three-generation Chinese family with dual Long QT and hypertrophic cardiomyopathy phenotypes for the first time. However, the clinical course among the family members was various, and the potential myocardial dysfunction has not been investigated. OBJECTIVES: The objective of this study was to investigate the echocardiographic and electrocardiographic characteristics in a genetic positive Chinese family with hypertrophic cardiomyopathy and further to explore the association between myocardial dysfunction and electric activity, and the identified mutations. METHODS: A comprehensive echocardiogram - standard two-dimensional Doppler echocardiography and three-dimensional speckle tracking echocardiography - and electrocardiogram were obtained for members in this family. RESULTS: As previously reported, four missense mutations - MYH7-H1717Q, KCNQ1-R190W, MYLK2-K324E, and TMEM70-I147T - were identified in this family. The MYH7-H1717Q mutation carriers had significantly increased left ventricular mass indices, elevated E/e' ratio, deteriorated global longitudinal stain, but enhanced global circumferential and radial strain compared with those in non-mutation patients (all p<0.05). The KCNQ1-R190W carriers showed significantly prolonged QTc intervals, and the MYLK2-K324E mutation carriers showed inverted T-waves (both p<0.05). However, the TMEM70-I147T mutation carriers had similar echocardiography and electrocardiographic data as non-mutation patients. CONCLUSIONS: Three of the identified four mutations had potential pathogenic effects in this family: MYH7-H1717Q was associated with increased left ventricular thickness, elevated left ventricular filling pressure, and altered myocardial deformation; KCNQ1-R190W and MYLK2-K324E mutations were correlated with electrocardiographic abnormalities reflected in long QT phenotype and inverted T-waves, respectively.


Assuntos
Cardiomiopatia Hipertrófica Familiar/diagnóstico , Ecocardiografia Doppler/métodos , Ecocardiografia Tridimensional/métodos , Predisposição Genética para Doença , Ventrículos do Coração/fisiopatologia , Contração Miocárdica/fisiologia , Volume Sistólico/fisiologia , Adolescente , Adulto , Idoso , Miosinas Cardíacas/genética , Miosinas Cardíacas/metabolismo , Cardiomiopatia Hipertrófica Familiar/genética , Cardiomiopatia Hipertrófica Familiar/fisiopatologia , Criança , China/epidemiologia , Eletrocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Mutação de Sentido Incorreto , Linhagem , Fenótipo , Adulto Jovem
3.
Minim Invasive Ther Allied Technol ; 27(2): 97-100, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28949276

RESUMO

A 70-year-old woman presented with severe hypertrophic obstructive cardiomyopathy (HOCM) (maximum ventricular septum thickness of 28 mm, peak pressure gradient (PG) in the left ventricular outflow tract (LVOT) of 153 mmHg). We performed percutaneous trans-apex intra-septal radiofrequency ablation (PTAISRA) of the interventricular septum under guidance of transthoracic echocardiography. At six-months follow up, the symptoms were significantly relieved; the septal thickness was reduced to 18 mm and the peak LVOT PG reduced to 44 mmHg. This case highlights a novel use of radiofrequency ablation for the treatment of HOCM. Long-term safety and efficacy merit evaluation.


Assuntos
Cardiomiopatia Hipertrófica/terapia , Ablação por Cateter/métodos , Idoso , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Feminino , Septos Cardíacos/diagnóstico por imagem , Humanos
4.
Cardiology ; 138(4): 228-237, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28866666

RESUMO

AIMS: We investigated the pathogenesis of MYH7-V878A and CACNA1C-A1594V mutations in a Chinese family with hypertrophic cardiomyopathy. METHODS: Clinical, electrocardiographic (ECG), echocardiographic, and cardiac magnetic resonance (CMR) examinations of members of a Chinese family were followed by exon and boarding intron analyses of 96 genes in the proband using second-generation sequencing. We confirmed the mutations by bidirectional Sanger sequencing in the members and in 300 healthy controls. RESULTS: We detected MYH7-V878A and CACNA1C-A1594V mutations in this family. The members with both mutations showed inverted T-waves and ST-segment depression in ECG recordings, severe left ventricular (LV) hypertrophy in echocardiography, and myocardial fibrosis in CMR; subject II-11 did not show late gadolinium enhancement. Among those with only the MYH7-V878A mutation, subject III-7 showed abnormal ECG recordings, asymmetric septal hypertrophy, and myocardial fibrosis, and subjects II-13 and III-15 showed some abnormal repolarization, borderline LV wall thickness, and normal CMR findings. Those with only the CACNA1C-A1594V mutation showed nearly normal readings in all examinations. The members with both mutations displayed more severe LV hypertrophy and elevated LV filling pressure than those with 1 or no mutation (p < 0.05). CONCLUSION: Our results suggest that the pathogenesis of MYH7-V878A and CACNA1C-A1594V mutations may have a cumulative effect.


Assuntos
Canais de Cálcio Tipo L/genética , Miosinas Cardíacas/genética , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/fisiopatologia , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Cadeias Pesadas de Miosina/genética , Adolescente , Adulto , Povo Asiático/genética , Estudos de Casos e Controles , Criança , Ecocardiografia , Eletrocardiografia , Éxons , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Adulto Jovem
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 34(4): 514-518, 2017 Aug 10.
Artigo em Zh | MEDLINE | ID: mdl-28777849

RESUMO

OBJECTIVE: To analyze the phenotype-genotype correlation of MYH7-V878A mutation. METHODS: Exonic amplification and high-throughput sequencing of 96-cardiovascular disease-related genes were carried out on probands from 210 pedigrees affected with hypertrophic cardiomyopathy (HCM). For the probands, their family members, and 300 healthy volunteers, the identified MYH7-V878A mutation was verified by Sanger sequencing. Information of the HCM patients and their family members, including clinical data, physical examination, echocardiography (UCG), electrocardiography (ECG), and conserved sequence of the mutation among various species were analyzed. RESULTS: A MYH7-V878A mutation was detected in five HCM pedigrees containing 31 family members. Fourteen members have carried the mutation, among whom 11 were diagnosed with HCM, while 3 did not meet the diagnostic criteria. Some of the fourteen members also carried other mutations. Family members not carrying the mutation had normal UCG and ECG. No MYH7-V878A mutation was found among the 300 healthy volunteers. Analysis of sequence conservation showed that the amino acid is located in highly conserved regions among various species. CONCLUSION: MYH7-V878A is a hot spot among ethnic Han Chinese with a high penetrance. Functional analysis of the conserved sequences suggested that the mutation may cause significant alteration of the function. MYH7-V878A has a significant value for the early diagnosis of HCM.


Assuntos
Povo Asiático/genética , Miosinas Cardíacas/genética , Cardiomiopatia Hipertrófica/genética , Mutação/genética , Cadeias Pesadas de Miosina/genética , Adulto , Sequência de Aminoácidos , Feminino , Estudos de Associação Genética/métodos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Adulto Jovem
6.
J Integr Plant Biol ; 56(3): 315-32, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24325391

RESUMO

In halophytic plants, the high-affinity potassium transporter HKT gene family can selectively uptake K⁺ in the presence of toxic concentrations of Na⁺. This has so far not been well examined in glycophytic crops. Here, we report the characterization of SbHKT1;4, a member of the HKT gene family from Sorghum bicolor. Upon Na⁺ stress, SbHKT1;4 expression was more strongly upregulated in salt-tolerant sorghum accession, correlating with a better balanced Na⁺ /K⁺ ratio and enhanced plant growth. Heterogeneous expression analyses in mutants of Saccharomyces cerevisiae and Arabidopsis thaliana indicated that overexpressing SbHKT1;4 resulted in hypersensitivity to Na⁺ stress, and such hypersensitivity could be alleviated with the supply of elevated levels of K⁺, implicating that SbHKT1;4 may mediate K⁺ uptake in the presence of excessive Na⁺. Further electrophysiological evidence demonstrated that SbHKT1;4 could transport Na⁺ and K⁺ when expressed in Xenopus laevis oocytes. The relevance of the finding that SbHKT1;4 functions to maintain optimal Na⁺ /K⁺ balance under Na⁺ stress to the breeding of salt-tolerant glycophytic crops is discussed.


Assuntos
Proteínas de Transporte de Cátions/genética , Família Multigênica , Proteínas de Plantas/genética , Potássio/metabolismo , Sódio/metabolismo , Sorghum/genética , Sorghum/fisiologia , Estresse Fisiológico/genética , Simportadores/genética , Sequência de Aminoácidos , Animais , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Transporte de Cátions/química , Proteínas de Transporte de Cátions/metabolismo , Evolução Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Teste de Complementação Genética , Ativação do Canal Iônico/efeitos dos fármacos , Cinética , Dados de Sequência Molecular , Mutação/genética , Oócitos/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Salinidade , Plantas Tolerantes a Sal/efeitos dos fármacos , Plantas Tolerantes a Sal/genética , Plantas Tolerantes a Sal/fisiologia , Cloreto de Sódio/farmacologia , Sorghum/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Simportadores/química , Simportadores/metabolismo , Fatores de Tempo , Xenopus
7.
Materials (Basel) ; 17(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38793494

RESUMO

X65 pipeline steel is widely used in the field of offshore oil and gas exploitation due to its excellent performance. However, due to the complex environment in the ocean, X65 pipeline steel is faced with a great risk of microbial corrosion failure. Therefore, it is of great significance to study the corrosion mechanism of X65 pipeline steel by microorganisms. In this paper, the corrosion effect of Pseudomonas aeruginosa (P. aeruginosa) secreting phenazine compounds on X65 pipeline steel was studied by the weight loss method, biofilm scanning electron microscopy analysis, surface corrosion morphology observation, electrochemical testing and medium pH test corrosion products. The results showed that the inoculation of P. aeruginosa accelerated the corrosion of X65 steel. After knocking out the phzM and phzS genes that regulate the synthesis of PYO, P. aeruginosa can still produce biofilms on the surface of X65 steel consistent with the morphology of wild-type P. aeruginosa, but the corrosion of X65 steel is significantly reduced. It is proved that PYO plays an important role in the corrosion process of P. aeruginosa on steel.

8.
BMJ Open ; 14(2): e078887, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38355185

RESUMO

OBJECTIVE: We hope to reveal the changing trends of chronic obstructive pulmonary disease (COPD) burden attributable to particulate matter pollution (PM2.5) and its age, period and cohort effects in China, Japan and Korea. DESIGN: We analysed the trend of COPD disease burden attributable to PM2.5 from 1990 to 2019 based on the latest Global Burden of Disease Database (GBD 2019) using JoinPoint model and analysed the effect of age, period and cohort on COPD burden attributable to PM2.5 in China, Japan and Korea from 1990 to 2019 using age-period-cohort model (model). SETTING: GBD data from 1990 to 2019. PARTICIPANTS: Data were publicly available and individuals were not involved. MAIN OUTCOMES: Outcomes included the age standardised mortality rate (ASMR), the age-standardised disability-adjusted life year (DALY), average annual per cent change (AAPC), net drift, local drift, longitudinal age curves, period (cohort) rate ratios, age (period, cohort) bias coefficient. RESULTS: From 1990 to 2019, the ASMR of COPD attributable to PM2.5 in China (AAPC=-5.862), Japan (AAPC=-1.715) and Korea (AAPC=-1.831) showed a downward trend. The age-standardised DALY of COPD attributable to PM2.5 in China (AAPC=-5.821), Japan (AAPC=-1.39) and Korea (AAPC=-1.239) showed a downward trend. Mortality of COPD attributable to PM2.5 increased slowly with age in Korea and Japan. Mortality of COPD attributable to PM2.5 in China decreased after rising (95% CI: 404.66 to 466.01). Mortality of COPD attributable to PM2.5 decreased over time in China and Korea, while it increased in Japan from 2015 to 2019. In China and Japan, mortality of COPD attributable to PM2.5 was approximately lower the later the birth, while in Korea it decreased after an increase (95% CI: 2.13 to 2.40) in the 1900-1910. CONCLUSIONS: Most COPD burden attributable to PM2.5 is on the decline; COPD mortality attributable to PM2.5 both increased with age and decreased with time and cohort. Countries with high burden should develop targeted measures to control PM2.5.


Assuntos
Carga Global da Doença , Doença Pulmonar Obstrutiva Crônica , Humanos , Japão/epidemiologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Efeitos Psicossociais da Doença , China/epidemiologia , República da Coreia/epidemiologia , Material Particulado/efeitos adversos , Anos de Vida Ajustados por Qualidade de Vida
9.
J Colloid Interface Sci ; 651: 172-181, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37542892

RESUMO

Transition metal borides (TMBs) or phosphides (TMPs) have attracted great attention to the design of bifunctional electrocatalysts for energy storage. The superaerophobicity and superhydrophilicity of the catalytic electrode surface are crucial factors to determine the reaction process of the gas electrode. Herein, we report a self-supported electrode of carbon nanotube (CNTs) array grown on carbon cloth (CC) modulated together by boron-doped cobalt phosphide (CoP-B/CNTs/CC). The electrode requires the overpotential of 73.8 mV and 189.5 mV at the current density of ±10 mA cm-2 for hydrogen and oxygen evolution reactions in an alkaline electrolyte (1.0 M KOH), respectively, meanwhile maintaining outstanding long-term durability for more than 300 h. The excellent activity of CoP-B/CNTs/CC is attributed to boron doping regulating its electronic structure and further enriching active sites. The attractive stability of CoP-B/CNTs/CC is due to the unique geometric structure of the self-supported electrode. Furthermore, the superaerophobicity and superhydrophilicity of the electrode surface also accelerate the reaction process of the gas electrode. Expectedly, water splitting cells assembled using CoP-B/CNTs/CC electrodes as cathode and anode, respectively, require a cell voltage of 1.54 V at 10 mA cm-2, which is lower than that of the Pt/C/CC||RuO2/CC couple (1.69 V at 10 mA cm-2). Importantly, CoP-B/CNTs/CC||CoP-B/CNTs/CC achieve stable cell voltage under the step current changes (10 mA cm-2, 50 mA cm-2, and 100 mA cm-2) over 300 h. This work highlights a new path to understanding the effects of the static and dynamic behavior of bubbles on the surface of self-supporting electrodes on catalytic performance.

10.
Clin Transl Oncol ; 25(12): 3460-3470, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37222951

RESUMO

PURPOSE: This study aimed to evaluate the role of NADPH in pancreatic ductal adenocarcinoma using bioinformatic analyses and experimental validations. METHODS: We compared the expression levels, performed GO and KEGG analysis of NADPH oxidase family and its regulatory subunits, and determined the survival of patients with pancreatic ductal adenocarcinoma by GEPIA, David and KM plotter. The relationship between their expression with immune infiltration levels, phagocytotic/NK cell immune checkpoints, recruitment-related molecules were detected by Timer 2.0 and TISIDB, respectively. Subsequently, their correlation with NK cell infiltration level was verified by immunohistochemistry. RESULTS: The expression of some members of the NADPH oxidase family and its regulatory subunits was significantly increased in pancreatic ductal adenocarcinoma tissues compared to that in normal tissues and was positively correlated with natural killer (NK) cell infiltration. Furthermore, the NADPH oxidase family and its regulatory subunits were associated with survival and immune status in patients with pancreatic ductal adenocarcinoma, including chemokines, immune checkpoints, and immune infiltration levels of NK cells, monocytes, and myeloid-derived suppressor cells. CONCLUSIONS: These results suggest the NADPH oxidase family and its regulatory subunits might serve as indicators for predicting the responsiveness to immunotherapy and outcome of patients with pancreatic ductal adenocarcinoma, providing a new perspective or strategy for immunotherapy in pancreatic ductal adenocarcinoma.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Prognóstico , NADPH Oxidases/uso terapêutico , Adenocarcinoma/patologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Imunoterapia , Biomarcadores
11.
Gene ; 888: 147739, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37633535

RESUMO

The active ingredients of many medicinal plants are the secondary metabolites associated with the growth period. Lonicera japonica Thunb. is an important traditional Chinese medicine, and the flower development stage is an important factor that influences the quality of medicinal ingredients. In this study, transcriptomics and metabolomics were performed to reveal the regulatory mechanism of secondary metabolites during flowering of L. japonica. The results showed that the content of chlorogenic acid (CGA) and luteolin gradually decreased from green bud stage (Sa) to white flower stage (Sc), especially from white flower bud stage (Sb) to Sc. Most of the genes encoding the crucial rate-limiting enzymes, including PAL, C4H, HCT, C3'H, F3'H and FNSII, were down-regulated in three comparisons. Correlation analysis identified some members of the MYB, AP2/ERF, bHLH and NAC transcription factor families that are closely related to CGA and luteolin biosynthesis. Furthermore, differentially expressed genes (DEGs) involved in hormone biosynthesis, signalling pathways and flowering process were analysed in three flower developmental stage.


Assuntos
Ácido Clorogênico , Lonicera , Ácido Clorogênico/metabolismo , Luteolina , Perfilação da Expressão Gênica , Lonicera/genética , Flores/genética , Flores/metabolismo , Hormônios/metabolismo , Transcriptoma/genética
12.
Heliyon ; 8(12): e12588, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36643323

RESUMO

Microbiologically influenced corrosion (MIC) has caused great losses to many industries. This paper aimed to study the corrosion behavior of P. aeruginosa on X65 steel. The corrosion behavior of P. aeruginosa on X65 steel under aerobic and anaerobic conditions was studied by scanning electron microscopy, energy dispersive spectrometer and electrochemical analysis techniques. The results showed that the corrosion rate of X65 steel in bacterial environment is higher than that in sterile environment. In anaerobic environment, the corrosion of P. aeruginosa is mainly secreted acidic metabolites, and alkaline substances are corroded in aerobic environment. In general, the corrosion of X65 steel by P. aeruginosa in aerobic environment is more serious than that in anaerobic environment.

13.
Microsyst Nanoeng ; 8: 91, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051747

RESUMO

The geometric designs of MEMS devices can profoundly impact their physical properties and eventual performances. However, it is challenging for researchers to rationally consider a large number of possible designs, as it would be very time- and resource-consuming to study all these cases using numerical simulation. In this paper, we report the use of deep learning techniques to accelerate the MEMS design cycle by quickly and accurately predicting the physical properties of numerous design candidates with vastly different geometric features. Design candidates are represented in a nonparameterized, topologically unconstrained form using pixelated black-and-white images. After sufficient training, a deep neural network can quickly calculate the physical properties of interest with good accuracy without using conventional numerical tools such as finite element analysis. As an example, we apply our deep learning approach in the prediction of the modal frequency and quality factor of disk-shaped microscale resonators. With reasonable training, our deep learning neural network becomes a high-speed, high-accuracy calculator: it can identify the flexural mode frequency and the quality factor 4.6 × 103 times and 2.6 × 104 times faster, respectively, than conventional numerical simulation packages, with good accuracies of 98.8 ± 1.6% and 96.8 ± 3.1%, respectively. When simultaneously predicting the frequency and the quality factor, up to ~96.0% of the total computation time can be saved during the design process. The proposed technique can rapidly screen over thousands of design candidates and promotes experience-free and data-driven MEMS structural designs.

14.
RSC Adv ; 12(35): 22555-22563, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36105998

RESUMO

The investigation of crystal field effects is significant for elucidating the spectral characteristics of Yb3+-doped sesquioxide crystals for ultrafast laser generation. The narrow spectra of Yb3+-doped single sesquioxide crystals limit the generation of ultrafast lasers; in this study, the Y3+ ions were introduced into Lu2O3 single crystals by the employment of ion replacement to broaden the spectra. To analyze the spectral broadening, the responsible crystal field parameters (CFPs) were calculated. The conversion of the host dominant ion and the distortion of the ligand affected the values and signs of the CFPs, and further determined the energy level splitting and fluorescence spectra. A linear relationship expressed by the semi-empirical equations for Yb3+-doped sesquioxide crystals was produced, which could be used for high throughput spectral prediction. Opposite variations of high- and low-frequency vibrational energies and the influence of the electron-phonon coupling on the spectra were also achieved. The redshift from the crystal field and the blueshift from the electron-phonon coupling make the optimal spectral broadening appear when x = 1.19 in the Yb:Lu x Y2-x O3 crystals. The results of these analyses could provide some key clues for the development of Yb3+-doped crystals for the generation and amplification of ultrafast lasers.

15.
ACS Appl Mater Interfaces ; 14(51): 56847-56855, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36524830

RESUMO

Electrocatalytic water splitting is a desirable and sustainable strategy for hydrogen production yet still faces challenges due to the sluggish kinetics and rapid deactivation of catalysts in the oxygen evolution process. Herein, we utilized the metal-catalyzed growth technology and phosphating process to fabricate self-supported electrodes (CoxPy@CNT-CC) composed of carbon nanotube (CNT) arrays grown on carbon cloth (CC); thereinto, cobalt-based phosphide nanoparticles (CoxPy) are uniformly encapsulated in the cavity of the CNTs. After further optimization, when the nanoparticles are in the composite phase (CoP2/Co2P), CoP2/Co2P@CNT-CC served as catalytic electrodes with the highest activity and stability for electrocatalytic water splitting in an alkaline medium (1.0 M KOH). The as-prepared CoP2/Co2P@CNT-CC integrates the advantages of the abundant active sites and confinement effect of CNTs, imparting promising electrocatalytic activities and stability in catalyzing both hydrogen evolution reaction and oxygen evolution reaction. Remarkably, electrocatalytic water splitting cells assembled using CoP2/Co2P@CNT-CC electrodes as the cathode and anode, respectively, require a cell voltage of 1.55 V at 10 mA cm-2, which is lower than that of the commercially noble Pt/C/CC and RuO2/CC catalyst couple (1.68 V). Besides, a CoP2/Co2P@CNT-CC||CoP2/Co2P@CNT-CC system shows outstanding durability for a period of 100 h at 10 mA cm-2. This work may provide new ideas for designing bifunctional electrocatalysts for applications in electrocatalytic water splitting.

16.
Int Immunopharmacol ; 94: 107474, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33611056

RESUMO

Platycodin D (PLD) is a saponin found in Platycodon grandiflorum, which has been reported to have anti-inflammatory effects. However, the effects of PLD on ulcerative colitis (UC) remain unknown. In this study, PLD showed the potential to reduce inflammation, ameliorate intestinal damage, and maintain intestinal integrity in DSS-induced colitis. However, the beneficial effect of PLD was reduced when macrophages were depleted, indicating the key role of macrophages in the beneficial effect of PLD in DSS-induced colitis. Meanwhile, we found that PLD inhibited the expression of M1 markers and promoted the expression of M2 markers in colon. Similarly, we found PLD significantly attenuated the levels of pro-inflammatory cytokines, increased the level of anti-inflammatory cytokine and altered macrophage proportions in LPS-stimulated RAW 264.7 cells in vitro. Moreover, treating LPS-stimulated RAW 264.7 cells with PLD increased the activation of the PI3K/Akt signaling pathway and decreased activation of NF-κB pathway. Furthermore, we found that the anti-inflammatory and macrophage polarization regulatory effects of PLD was Adenosine 5'-monophosphate-activated protein kinase (AMPK)-dependent. These results indicate that PLD attenuates DSS-induced colitis and LPS-induced inflammation, and the mechanism behind the phenomenon may be regulating macrophage polarization via activation of AMPK. Our study provides a theoretical basis for PLD to be used as a potential treatment of colitis.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/tratamento farmacológico , Saponinas/uso terapêutico , Triterpenos/uso terapêutico , Proteínas Quinases Ativadas por AMP/imunologia , Animais , Anti-Inflamatórios/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Colite/induzido quimicamente , Colite/imunologia , Colite/patologia , Colo/efeitos dos fármacos , Colo/imunologia , Colo/patologia , Citocinas/genética , Sulfato de Dextrana , Escherichia coli , Lipopolissacarídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7 , Saponinas/farmacologia , Triterpenos/farmacologia
17.
J Phys Chem Lett ; 12(3): 1018-1024, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33470817

RESUMO

The inorganic perovskite CsPbI3 that exists in the form of a quantum dot (QD) shows a stable cubic structure, attracting much attention for its application in solar cells. However, too many grain boundaries in the perovskite QD (PQD) layer block the transport of carriers, resulting in the potential loss of solar cells. Herein, we devise a gradient-band alignment (GBA) homojunction, which is constructed from three layers of PQDs with different band-gaps to form a gradient energy alignment. The GBA structure facilitated the charge extraction and increased the carrier diffusion length of the PQD layer because of the additional driving force for the electrons. In addition, the homojunction made from the same substance could minimize the lattice mismatch of the active layer. As a result, the champion solar cell based on the GBA homojunction layer achieved a high open voltage VOC of 1.25 V and a power conversion efficiency (PCE) of 13.2%.

18.
Nanomaterials (Basel) ; 9(12)2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31817681

RESUMO

A technique for scalable spray coating of colloidal CdSeTe quantum dots (QDs) for photovoltaics and photodetector applications is presented. A mixture solvent with water and ethanol was introduced to enhance the adhesive force between QDs and the substrate interface. The performance of the detector reached the highest values with 40 spray coating cycles of QD deposition. The photodetectors without bias voltage showed broadband response in the wavelength range of 300-800 nm, and high responsivity of 15 mA/W, detectivity of more than 1011 Jones and rise time of 0.04 s. A large size QD-logo pattern film (10 × 10 cm2) prepared by the spray coating process displayed excellent uniformity of thickness and absorbance. The large area detectors (the active area 1 cm2) showed almost the same performance as the typical laboratory-size ones (the active area 0.1 cm2). Our study demonstrates that the spray coating is a very promising film fabrication technology for the industrial-scale production of optoelectronic devices.

19.
J Phys Chem Lett ; 10(21): 6720-6726, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31549508

RESUMO

Colloidal InP quantum dots (QDs) have been considered as one of the most promising candidates for display and biolabeling applications because they are intrinsically toxicity-free and exhibit high photoluminescence. On account of the uncontrollable nucleation and growth during the synthesis of InP, obtaining high-quality blue-emitting InP QDs with uniform size distribution remains a challenge. Herein, we employ a novel synthetic approach for producing blue-emitting InP/ZnS core/shell QDs with the assistance of copper cations. The studies reveal that the copper ions could combine with phosphorus precursor to form hexagonal Cu3-xP nanocrystals, which competed with the nucleation process of InP QDs, resulting in the smaller sized InP QDs with blue photoluminescence emission. After the passivation of InP QDs with the ZnS shell, the synthesized InP/ZnS core/shell QDs present bright blue emission (∼425 nm) with a photoluminescence quantum yield of ∼25%, which is the shortest wavelength emission for InP QDs to date. This research provides a new way to synthesize ultrasmall semiconductor nanocrystals.

20.
ACS Appl Mater Interfaces ; 10(41): 35656-35663, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30251817

RESUMO

A novel hybrid hole transport layer (HTL) of CuInSe2 quantum dots (QDs)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) was developed to enhance the performance of halide metal perovskite (MAPbI3)-based photodetectors. The introduction of CuInSe2 QDs not only improved the wettability of the PEDOT:PSS HTL for the growth of perovskite crystals but also facilitated the transportation of holes from the perovskite to the HTL. As a result, both responsivity and detectivity of the device were increased dramatically by CuInSe2 QDs hybrid HTL, showing excellent photoresponsivity of 240 mA/W, larger ratio of photocurrent density to dark current density of 4.1 × 106, fast on-off switching properties of <0.02 s, and remarkable detectivity values of 1.02 × 1013 Jones at 580 nm and above 5.01 × 1012 Jones over the visible light region without an external bias voltage. In addition, the photodetectors also showed excellent thermal stability in the range of 10-110 °C. Therefore, a unique design idea of a hole transport material would be an anticipated direction for efficient halide metal perovskite-based devices.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA