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1.
Adv Mater ; : e2401236, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38599344

RESUMO

Common polymeric conductive electrodes, such as polyethylene terephthalate (PET) coated with indium tin oxide, face a major challenge due to their low processing-temperature limits, attributed to PET's low glass transition temperature (Tg) of (70-80 °C). This limitation significantly narrows the scope of material selection, limits the processing techniques applicable to the low Tg, and hinders the ripened technology transfer from glass substrates to them. Addressing the temperature constraints of the flexible substrates is impactful yet underexplored, with broader implications for fields beyond photovoltaics. Here, a new thermal radiation annealing methodology is introduced to address this issue. By applying the above Tg radiation annealing in conjunction with thermoelectric cooling, highly ordered molecular packing on PET substrates is successfully created, which is exclusively unachievable due to PET's low thermal tolerance. As a result, in the context of perovskite solar cells, this approach enables the circumvention of high-temperature annealing limitations of PET substrates, leading to a remarkable flexible device efficiency of 22.61% and a record fill factor of 83.42%. This approach proves especially advantageous for advancing the field of flexible optoelectronic devices.

2.
Angew Chem Int Ed Engl ; : e202403068, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687308

RESUMO

Organic self-assembled molecules (OSAMs) based hole transporting materials play a pivotal role in achieving highly efficient and stable inverted perovskite solar cells (IPSCs). However, the reported carbazol-based OSAMs have serious drawbacks, such as poor solubility in alcohol solution, worse matched energy arrangement with perovskite, and limited molecular species, which greatly limit the device performance. To address above problems, a novel OSAM 4-(3,6-glycol monomethyl ether-9H-carbazol-9-yl) butyl]phosphonic acid (GM-4PACz) was synthesized as hole-transporting material by introducing glycol monomethyl ether (GM) side chains at carbazolyl unit. GM groups enhance the surface energy of Indium Tin Oxide (ITO)/SAM substrate to facilitate the nucleation and growth of up perovskite film, suppress cation defects, release the residual stress at SAM/perovskite interface, and evaluate energy level for matching with perovskite. Consequently, the GM-4PACz based IPSC achieves a champion PCE of 25.52%, a respectable open-circuit voltage (VOC) of 1.21 V, a high stability, possessing 93.29% and 91.75% of their initial efficiency after aging in air for 2000 h or tracking at maximum power point for 1000 h, respectively.

3.
Adv Mater ; 35(31): e2301140, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36972593

RESUMO

Surface-defect-triggered non-radiative charge recombination and poor stability have become the main roadblock to continued improvement in inorganic perovskite solar cells (PSCs). Herein, the main culprits are identified on the inorganic perovskite surface by first-principles calculations, and to purposefully design a brand-new passivator, Boc-S-4-methoxy-benzyl-l-cysteine (BMBC), whose multiple Lewis-based functional groups (NH, S and CO) to suppress halide vacancies and coordinate with undercoordinated Pb2+ through typical Lewis baseacid reactions. The tailored electron-donating methoxyl group (CH3 O-) can cause an increased electron density on the benzene ring, which strengthens the interaction with undercoordinated Pb2+ via electrostatic interactions. This BMBC passivation can reduce the surface trap density, enlarge grains, prolong the charge lifetime, and cause a more suitable energy-level alignment. In addition, the hydrophobic tert-butyl in butoxycarbonyl (Boc-) group ensures that BMBC is uniformly covered and prevents harmful aggregation through steric repulsion at the perovskite/hole-transporting layer (HTL) interface, thus providing a hydrophobic umbrella to resist moisture invasion. Consequently, the combination of the above increases the efficiency of CsPbI3-x Brx PSC from 18.6% to 21.8%, the highest efficiency for this type of inorganic metal halide PSCs so far, as far as it is known. Moreover, the device exhibits higher environmental and thermal stability.

4.
Adv Sci (Weinh) ; 9(36): e2204486, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36344454

RESUMO

Doping of all-inorganic lead halide perovskites to enhance their photovoltaic performance and stability has been reported to be effective. Up to now most studies have focused on the doping of elements in to the perovskite lattice. However, most of them cannot be doped into the perovskite lattice and the roles of these dopants are still controversial. Herein,the authors introduce CdI2 as an additive into CsPbI3-x Brx and use it as active layer to fabricate high-performance inorganic perovskite solar cells (PSCs). Cd with a smaller radius than Pb can partially substitute Pb in the perovskite lattice by up to 2 mol%. Meanwhile, the remaining Cd stays on the surface and grain boundaries (GB) of the perovskite film in the form of Cs2 CdI4-x Br-x , which is found to reduce non-radiative recombination. These effects result in prolonged charge carrier lifetime, suppressed defect formation, decreased GBs, and an upward shift of energybands in the Cd-containing film. A champion efficiency of 20.8% is achieved for Cd-incorporated PSCs, together with improved device ambient stability. This work highlights the importance of simultaneous lattice engineering, defectcontrol and atomic-level characterization in achieving high-performance inorganic PSCs with well-defined structure-property relationships.

5.
World J Clin Cases ; 9(20): 5535-5539, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34307606

RESUMO

BACKGROUND: Primary cardiac tumors are uncommon, of which cardiac myxoma accounts for 50%-80%. Left ventricular myxoma has been rarely reported, accounting for only 3%-4% of all cardiac myxomas. Multiple left ventricular myxomas are, relatively, even rarer. CASE SUMMARY: In this report, we present a case of multiple left ventricular myxomas combined with severe rheumatic valve lesions. Symptomatically, the patient presented with fatigue, shortness of breath, and palpitation after activities. The patient underwent complete surgical resection of multiple left ventricular myxomas combined with mechanical replacement of the mitral and aortic valves, tricuspid valvuloplasty. The patient recovered well after the operation, with no obvious related complications. CONCLUSION: Multiple left ventricular myxomas may coexist with severe rheumatic valve disease. Operation is an effective treatment.

6.
High Alt Med Biol ; 22(3): 285-292, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34143663

RESUMO

Wang, Man, Mengxue Liu, Jia Huang, Dan Fan, Shengzhong Liu, Tao Yu, Keli Huang, Xinchuan Wei, and Qian Lei. Long-term high-altitude exposure does not increase the incidence of atrial fibrillation associated with organic heart diseases. High Alt Med Biol. 22:285-292, 2021. Background: Atrial fibrillation (AF) is one of the most common arrhythmias and is associated with several complications following cardiac surgery. However, the differences in the incidence of AF associated with organic heart diseases between highland and lowland populations have not been comprehensively studied. Methods: In this retrospective study, a total of 2,316 highland and lowland patients who underwent cardiac surgery between January 2013 and December 2018 in a single center were enrolled. According to the altitude of residence, patients were divided into high-altitude (>1,500 m) and low-altitude (<1,500 m) groups. A propensity score matching analysis was performed to estimate the association of lifetime high-altitude exposure with AF. Results: Among the enrolled patients, 239 (10.9%) were from a high-altitude plateau, while 1,946 (89.1%) were from a low-altitude area. There were statistical differences in age, gender, European System for Cardiac Operative Risk Evaluation, and other factors, between the two groups (p < 0.05). According to the propensity score, 237 patients in the high-altitude group were successfully matched to 237 patients in the low-altitude group without significant difference in baseline data (p > 0.05). Among the matched patients, 125 patients (26.4%) suffered from AF, with 66 (27.8%) in the high-altitude group and 59 (24.9%) in the low-altitude group. The incidence of AF was statistically similar between the two groups and not significantly influenced by long-term high-altitude exposure (odds ratio 1.07; 95% confidence interval 0.71-1.60, p > 0.05). Conclusion: Long-term high-altitude exposure did not significantly increase the occurrence of AF in patients with organic heart diseases. Clinical Trial No. ChiCTR1900028612.


Assuntos
Fibrilação Atrial , Cardiopatias , Altitude , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/etiologia , Humanos , Incidência , Masculino , Estudos Retrospectivos , Fatores de Risco
7.
J Phys Chem Lett ; 10(19): 5687-5693, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31495169

RESUMO

Two-dimensional (2D) hybrid organic-inorganic metal halide perovskites (HOIPs) with considerably hydrophobic phenyl ethylammonium (PEA) organic cations have been used in highly efficient solar cells and LEDs, which are stable and enjoy a long lifetime, even when exposed to moisture. Different from other 2D HOIPs with alkyl amine cations, a benzene ring is present in the PEA cation. Until recently, an understanding of the effects of PEA on the structural, electronic, and optical properties of 2D HOIPs under pressure has remained limited. We find that there is a direct-indirect band gap transition at around 5.8 GPa and that the direct band gap recovers when the pressure is released. The stacking order of the benzene rings in the PEA cation plays a critical role in the mechanical and electronic properties. Our present work demonstrates that 2D HOIPs with organic cations containing benzene rings prove highly attractive for use in flexible optoelectronics.

8.
Transplant Proc ; 51(6): 2060-2065, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31399184

RESUMO

OBJECTIVE: To explore the protective effect and underlying mechanism of allicin (ALC) on myocardial ischemia reperfusion (MI/R) injury in rats. METHODS: The model of MI/R injury in rats was induced by ligating the left anterior descending branch of the coronary artery. Thirty male Sprague-Dawley rats were randomly divided into 3 equal groups (n = 10): sham group, MI/R injury group, and ALC precondition group. Enzyme-linked immunosorbent assay was used to examine the expression of cardiac troponin I, CK-MB, interleukin-6, tumor necrosis factor-α, and interleukin-8 in the rats' serum. Hematoxylin and eosin staining was used to observe the myocardial pathologic morphology. A physiological recorder was used to measure cardiac systolic and diastolic function. Western blot analysis was used for detecting the expression of p38 and p-p38 in myocardium. The content of malondialdehyde and the activity of superoxide dismutase, catalase, and glutathione peroxidase in myocardium were examined by automatic analysis with the thiobarbituric acid chromogenic and dinitrobenzoic acid methods, respectively. RESULTS: ALC can significantly decrease the expression of cardiac troponin I, CK-MB, interleukin-6, tumor necrosis factor-α, and interleukin-8 in the serum and reduce the myocardial pathologic injury and the expression of malondialdehyde and p-p38 in myocardial tissue. Moreover, ALC can upregulate the activity of superoxide dismutase, catalase, and glutathione peroxidase and improve myocardial systolic and diastolic function with no influence on the expression of p38. CONCLUSION: ALC can protect rats against MI/R injury by suppressing inflammation and oxidative stress. The mechanism is associated with alleviating the activation of p38 signaling.


Assuntos
Coração/efeitos dos fármacos , Inflamação/patologia , Traumatismo por Reperfusão Miocárdica/patologia , Estresse Oxidativo/efeitos dos fármacos , Ácidos Sulfínicos/farmacologia , Animais , Dissulfetos , Inflamação/metabolismo , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Ratos , Ratos Sprague-Dawley
9.
Chin Med J (Engl) ; 132(12): 1414-1419, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31205098

RESUMO

BACKGROUND: Perioperative and median-term follow-up outcomes have not been compared among procedures using radiofrequency ablation devices for permanent atrial fibrillation with concomitant rheumatic valve disease. We compared the sinus rhythm restoration efficacy of "non-irrigation" ablation forceps and an "irrigation" ablation device in patients with rheumatic valve disease undergoing a modified Cox maze radiofrequency ablation procedure due to permanent atrial fibrillation. METHODS: Data of 278 patients with rheumatic valve disease from the Cardiac Surgery Department of Sichuan Provincial People's Hospital who underwent the modified Cox maze radiofrequency ablation procedure between May 2013 and May 2017 were reviewed. The procedure was performed using "non-irrigation" ablation forceps (AtriCure, group A) in 149 patients and an "irrigation" ablation device (Medtronic, group M) in 129 patients. Data were collected prospectively, and follow-up was documented and compared between the groups. RESULTS: The radiofrequency procedure duration was 28.9 ±â€Š3.8 min in group A and 29.5 ±â€Š2.8 min in group M (t = 1.623, P = 0.106). The predicted radiofrequency time to the left atrium diameter was (Ya = 0.4964 X + 0.3762, R = 0.74) in group A and (Ym = 0.4331 X + 4.3563, R = 0.8435) in group M. The sinus rhythm (SR) conversion rate without use of anti-arrhythmic drugs was similarly good in groups A and M, with 75.2%, 72.5%, and 70.5% vs. 73.6%, 71.3%, and 69.8% at discharge, 6 and 12 months, respectively (F = 0.084, F = 0.046, F = 0.046, P > 0.05, respectively). CONCLUSION: Two types of radiofrequency ablation devices characteristic of "non-irrigation" and "irrigation" bipolar ablation forceps were similarly efficient at SR restoration.


Assuntos
Fibrilação Atrial/terapia , Doenças das Valvas Cardíacas/terapia , Ablação por Radiofrequência/métodos , Adulto , Ablação por Cateter/métodos , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Cardiopatia Reumática/terapia , Insuficiência da Valva Tricúspide/terapia
10.
Cardiol Res Pract ; 2019: 6280194, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31143478

RESUMO

BACKGROUND: To study the expression and clinical significance of long noncoding RNA- (lncRNA-) MIAT in patients with coronary atherosclerotic heart disease (CAD). METHODS: Serum MIAT, interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in 106 CAD patients and 89 healthy donors were detected. Correlations between serum MIAT and serum IL-6 and TNF-α were analyzed. Risk factors for patients with CAD were analyzed by multiple factor analysis. RESULTS: Compared with healthy donors, serum lncRNA-MIAT was significantly increased in CAD patients. Serum MIAT was positively correlated with serum IL-6 and TNF-α in CAD. Multivariate analysis found that hypertension (OR (95% CI) = 3.471 (2.180-4.091), P=0.011), diabetes (OR (95% CI) = 3.682 (1.698-4.897), P=0.003), HDL-C (OR (95% CI) = 3.372 (1.760-6.920), P=0.001), and serum MIAT expression (OR (95% CI) = 2.687 (1.683-7.468), P=0.001) were independent risk factors for CAD. CONCLUSIONS: Serum lncRNA-MIAT in CAD patients was significantly increased, which may be a potential marker for diagnosis and prognosis of CAD.

11.
J Cell Biochem ; 120(8): 13226-13236, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30887575

RESUMO

Myocardial infarction (MI) remains a severe cardiac disease because of its high incidence and mortality worldwide. A growing body of recent investigations have confirmed that LINC00961 acts as a tumor suppressor in diverse malignancies. However, the biological significance of LINC00961 and its molecular mechanism in MI are still elusive. Hypoxia is the leading cause of MI and induces myocardial injury. In this study, we found the upregulated expression of LINC00961 in cardiomyocytes H9c2 after hypoxia treatment. Knockdown of LINC00961 ameliorated hypoxia-induced cell injury by facilitating cell viability while repressing cell apoptosis. The significant increase of signal transducer and activator of transcription 1 (STAT1) expression and phosphorylation levels was observed in hypoxia-induced cells and proved to exacerbate hypoxia injury. In addition, STAT1 transcriptionally activated LINC00961 by binding to LINC00961 promoter. Furthermore, our results validated that suppressing LINC00961 contributed to the remarkable diminution in the phosphorylation levels of phosphoinositide 3-kinases (PI3K), AKT, and glycogen synthase kinase-3ß (GSK3ß). Inhibition of PI3K/AKT signaling or GSK3ß pathway rescued the effects of LINC00961 knockdown on the hypoxia-induced injury of cardiomyocytes. Namely, we concluded that STAT1-avtiviated LINC00961 accelerated MI via the PI3K/AKT/GSK3ß pathway, which may provide clues for the treatment of patients with MI.


Assuntos
Glicogênio Sintase Quinase 3 beta/metabolismo , Infarto do Miocárdio/metabolismo , Peptídeos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT1/metabolismo , Apoptose/genética , Apoptose/fisiologia , Linhagem Celular , Imunoprecipitação da Cromatina , Glicogênio Sintase Quinase 3 beta/genética , Humanos , Infarto do Miocárdio/genética , Peptídeos/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Fator de Transcrição STAT1/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
12.
Adv Sci (Weinh) ; 5(12): 1801216, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30581712

RESUMO

Nickel is regarded as the best alternative metal electrocatalyst to platinum for hydrogen evolution reaction (HER). Success in developing a quasi-amorphous metallic nickel (QAMN) nanopowder catalyst using a two-step chemical route for efficient and durable HER in alkaline solution is reported. It is found that the QAMN electrocatalyst exhibits essentially zero overpotential at the cathodic onset while delivering 10 mA cm-2 at an overpotential of only 240 mV; both performances are far better than what was reported previously using prior metallic nickel catalysts. Taking into account increased surface area, further enhanced activity is attributed to the superior intrinsic activity. Meanwhile, the QAMN catalyst shows excellent stability in accelerated and interrupted polarization in alkaline solution for tens of hours. This study provides a new chemical means to prepare amorphous metallic materials for more efficient catalysis.

13.
Nat Commun ; 9(1): 3880, 2018 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-30250031

RESUMO

Besides high efficiency, the stability and reproducibility of perovskite solar cells (PSCs) are also key for their commercialization. Herein, we report a simple perovskite formation method to fabricate perovskite films with thickness over 1 µm in ambient condition on the basis of the fast gas-solid reaction of chlorine-incorporated hydrogen lead triiodide and methylamine gas. The resultant thick and smooth chlorine-incorporated perovskite films exhibit full coverage, improved crystallinity, low surface roughness and low thickness variation. The resultant PSCs achieve an average power conversion efficiency of 19.1 ± 0.4% with good reproducibility. Meanwhile, this method enables an active area efficiency of 15.3% for 5 cm × 5 cm solar modules. The un-encapsulated PSCs exhibit an excellent T80 lifetime exceeding 1600 h under continuous operation conditions in dry nitrogen environment.

14.
ACS Appl Mater Interfaces ; 8(28): 18165-72, 2016 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-27348055

RESUMO

Ag nanoparticle (NP)-sensitized WO3 hollow nanospheres (Ag-WO3-HNSs) are fabricated via a simple sonochemical synthesis route. It is found that the Ag-WO3-HNS shows remarkable performance in gas sensors. Field-emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM) images reveal that the Agx-WO3 adopts the HNS structure in which WO3 forms the outer shell framework and the Ag NPs are grown on the inner wall of the WO3 hollow sphere. The size of the Ag NPs can be controlled by adjusting the addition amount of WCl6 during the reaction. The sensor Agx-WO3 exhibits extremely high sensitivity and selectivity toward alcohol vapor. In particular, the Ag(15nm)-WO3 sensor shows significantly lower operating temperature (230 °C), superior detection limits as low as 0.09 ppb, and faster response (7 s). Light illumination was found to boost the sensor performance effectively, especially at 405 and 900 nm, where the light wavelength resonates with the absorption of Ag NPs and the surface oxygen vacancies of WO3, respectively. The improved sensor performance is attributed to the localized surface plasmon resonance (LSPR) effect.

15.
Nanoscale ; 8(16): 8696-703, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27053379

RESUMO

By taking advantages of both grinding and sonication, an effective exfoliation process is developed to prepare two-dimensional (2D) molybdenum oxide (MoO3) nanosheets. The approach avoids high-boiling-point solvents that would leave a residue and cause aggregation. Gas sensors fabricated using the 2D-MoO3 nanosheets provide a significantly enhanced chemical sensor performance. Compared with the sensors using bulk MoO3, the response of the 2D-MoO3 sensor increases from 7 to 33; the sensor response time is reduced from 27 to 21 seconds, and the recovery time is shortened from 26 to 10 seconds. We attribute the superior performance to the 2D-structure with a much increased surface area and reactive sites.

16.
Colloids Surf B Biointerfaces ; 117: 346-53, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24681046

RESUMO

Cisplatin-encapsulating maleimide-polyethylene glycol- Poly(d,l-lactic-co-glycolide) (cis-encapsulating mal-PEG-PLGA) particles were produced using the electrospray technique and bioconjugated with CD44 monoclonal antibody, targeting the counterpart receptor. The produced suspension of cis-encapsulating CD44-PEG-PLGA particles contains an antibody loading of 12.65-15.17 µg/mL and efficiently targets a CD44-overexpressed ovarian cancer cell line, such as CP70 and SKOV-3, within 6h of treatment, which was determined by Bradford assay, immunofluorescence analysis, and confocal laser scanning microscopic (CLSM) study. Most importantly, no tedious multi-step bioconjugation procedures are needed to synthesize mal-PEG-PLGA vehicles for antibody and drug loading, avoiding the undesirable hydrolysis of mal-PEG moiety and so successfully generating the cis-encapsulating mal-PEG-PLGA particles within one step. After conjugation of the CD44 antibody, the produced cis-encapsulating CD44-PEG-PLGA particles exhibited a better anti-proliferative ability against ovarian cancer cells compared to free form of cisplatin and PLGA particles without CD44 conjugation. Notably, the cis-encapsulating CD44-PEG-PLGA particles have approximately 10-14% greater the anti-proliferative ability against CP70 and SKOV-3 cells at a concentration of 1.25 µM, which falls within the concentrations used in chemotherapy. The proposed antibody-functionalization strategy represents an excellent platform for preparing particles with targeting ability in cancer therapy in vitro or in vivo.


Assuntos
Anticorpos/química , Cisplatino/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Ácido Láctico/química , Neoplasias Ovarianas/tratamento farmacológico , Tamanho da Partícula , Polietilenoglicóis/química , Ácido Poliglicólico/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/química , Cisplatino/farmacologia , Feminino , Fluoresceína-5-Isotiocianato/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Maleimidas/química , Microscopia Confocal , Microscopia Eletrônica de Varredura , Neoplasias Ovarianas/patologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
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