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1.
Small ; 20(22): e2309009, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38100243

RESUMEN

Using seeds to control the crystallization of perovskite film is an effective strategy for achieving high-efficiency perovskite solar cells (PSCs). Owing to their excellent environmental stability brought by their long alkyl chain, n-butylammonium (BA) cations are widely used for fabricating efficient and stable PSCs. However, BA-based 2D perovskite is seldom been investigated as a seed. Here, BA2PbI4 is employed to regulate the crystallization of PbI2, acting as nucleation centers. As a result, porous PbI2 film with high crystallinity is obtained, which allows the realization of perovskite film with preferential crystal orientations of (001) and large grain size of over 2 µm. The corresponding PSC achieves a high power conversion efficiency (PCE) of 24.30% and exhibits satisfactory stability, retaining 91.70% of the initial PCE after 300 h of thermal aging at 85°C.

2.
Angew Chem Int Ed Engl ; : e202414118, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160140

RESUMEN

Trap-assisted non-radiative recombination losses and moisture-induced degradation significantly impede the development of highly efficient and stable inverted (p-i-n) perovskite solar cells (PSCs), which require high-quality perovskite bulk. In this research, we mitigate these challenges by integrating thermally stable perovskite layers with Lewis base covalent organic frameworks (COFs). The ordered pore structure and surface binding groups of COFs facilitate cyclic, multi-site chelation with undercoordinated lead ions, enhancing the perovskite quality across both its bulk and grain boundaries. This process not only reduces defects but also promotes improved energy alignment through n-type doping at the surface. The inclusion of COF dopants in p-i-n devices achieves power conversion efficiencies (PCEs) of 25.64% (certified 24.94%) for a 0.0748-cm2 device and 23.49% for a 1-cm2 device. Remarkably, these devices retain 81% of their initial PCE after 978 hours of accelerated aging at 85˚C, demonstrating remarkable durability. Additionally, COF-doped devices demonstrate excellent stability under illumination and in moist conditions, even without encapsulation.

3.
Angew Chem Int Ed Engl ; 62(41): e202311865, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37615050

RESUMEN

Passivating the interfaces between the perovskite and charge transport layers is crucial for enhancing the power conversion efficiency (PCE) and stability in perovskite solar cells (PSCs). Here we report a dual-interface engineering approach to improving the performance of FA0.85 MA0.15 Pb(I0.95 Br0.05 )3 -based PSCs by incorporating Ti3 C2 Clx Nano-MXene and o-TB-GDY nanographdiyne (NanoGDY) into the electron transport layer (ETL)/perovskite and perovskite/ hole transport layer (HTL) interfaces, respectively. The dual-interface passivation simultaneously suppresses non-radiative recombination and promotes carrier extraction by forming the Pb-Cl chemical bond and strong coordination of π-electron conjugation with undercoordinated Pb defects. The resulting perovskite film has an ultralong carrier lifetime exceeding 10 µs and an enlarged crystal size exceeding 2.5 µm. A maximum PCE of 24.86 % is realized, with an open-circuit voltage of 1.20 V. Unencapsulated cells retain 92 % of their initial efficiency after 1464 hours in ambient air and 80 % after 1002 hours of thermal stability test at 85 °C.

4.
J Recept Signal Transduct Res ; 42(2): 117-124, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33349105

RESUMEN

Cadmium (Cd) has a direct toxic effect on bones. Statins such as simvastatin have protective effects on various diseases, including on tissue injury. The current study revealed the efficacy of simvastatin on Cd-induced preosteoblast injury. Preosteoblast MC3T3-E1 cells were incubated with various doses of CdCl2 for 12 h, 24 h and 48 h, and then the cell cytotoxicity was assessed using MTT assay and flow cytometry, respectively. The expression level of Nox4 was assessed by Western blot and qRT-PCR. The morphological appearance of MC3T3-E1 cells was observed under a microscope. Cells exposed to CdCl2 (5 µM) were further treated by simvastatin at various doses, subsequently cell viability, apoptosis and the expression of Nox4 were measured. Furthermore, to confirm the protective effects of simvastatin on Cd-induced pre-osteoblast injury, functional rescue assays were performed after corresponding cell treatment by simvastatin (10-8 M), CdCl2 (5 µM), and overexpression of Nox4. Expressions of cell apoptosis-related markers were measured by Western blot and qRT-PCR. The results revealed that CdCl2 caused MC3T3-E1 cell injury because the cell viability was decreased and the apoptosis was increased. Nox4 expression was up-regulated with the increase of CdCl2 concentrations. Simvastatin increased the cell viability, relieved the cell apoptosis and Nox4 expression previously increased by CdCl2. The effects of CdCl2 on MC3T3-E1 cells and Nox4 expression could be attenuated by simvastatin, and promoted by Nox4 overexpression. The current study found that simvastatin protects Cd-induced preosteoblast injury via Nox4, thus, it can be used as a potential drug for treating cadmium-induced bone injury.


Asunto(s)
Cadmio , Simvastatina , Apoptosis , Cadmio/metabolismo , Cadmio/farmacología , Línea Celular , Osteoblastos , Simvastatina/metabolismo , Simvastatina/farmacología
5.
BMC Cardiovasc Disord ; 21(1): 96, 2021 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-33593294

RESUMEN

BACKGROUND: Sevoflurane postconditioning (SevP) effectively relieves myocardial ischemia/reperfusion (I/R) injury but performs poorly in the diabetic myocardium. Previous studies have revealed the important role of increased oxidative stress in diabetic tissues. Notably, mitochondrial fission mediated by dynamin-related protein 1 (Drp1) is an upstream pathway of reactive oxygen production. Whether the ineffectiveness of SevP in the diabetic myocardium is related to Drp1-dependent mitochondrial fission remains unknown. This study aimed to explore the important role of Drp1 in the diabetic myocardium and investigate whether Drp1 inhibition could restore the cardioprotective effect of SevP. METHODS: In the first part of the study, adult male Sprague-Dawley rats were divided into 6 groups. Rats in the diabetic groups were fed with high-fat and high-sugar diets for 8 weeks and injected intraperitoneally with streptozotocin (35 mg/kg). Myocardial I/R was induced by 30 min of occlusion of the left anterior descending branch of the coronary artery followed by 120 min of reperfusion. SevP was applied by continuous inhalation of 2.5 % sevoflurane 1 min before reperfusion, which lasted for 10 min. In the second part of the study, we applied mdivi-1 to investigate whether Drp1 inhibition could restore the cardioprotective effect of SevP in the diabetic myocardium. The myocardial infarct size, mitochondrial ultrastructure, apoptosis index, SOD activity, MDA content, and Drp1 expression were detected. RESULTS: TTC staining and TUNEL results showed that the myocardial infarct size and apoptosis index were increased in the diabetic myocardium. However, SevP significantly alleviated myocardial I/R injury in the normal myocardium but not in the diabetic myocardium. Additionally, we found an elevation in Drp1 expression, accompanied by more severe fission-induced structural damage and oxidative stress in the diabetic myocardium. Interestingly, we discovered that the beneficial effect of SevP was restored by mdivi-1, which significantly suppressed mitochondrial fission and oxidative stress. CONCLUSIONS: Our study demonstrates the crucial role of mitochondrial fission dependent on Drp1 in the diabetic myocardium subjected to I/R, and strongly indicates that Drp1 inhibition may restore the cardioprotective effect of SevP in diabetic rats.


Asunto(s)
Anestésicos por Inhalación/farmacología , Diabetes Mellitus Experimental/metabolismo , Dinaminas/metabolismo , Infarto del Miocardio/prevención & control , Daño por Reperfusión Miocárdica/prevención & control , Miocitos Cardíacos/efectos de los fármacos , Sevoflurano/farmacología , Animales , Apoptosis/efectos de los fármacos , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/patología , Masculino , Mitocondrias Cardíacas/efectos de los fármacos , Mitocondrias Cardíacas/metabolismo , Mitocondrias Cardíacas/patología , Dinámicas Mitocondriales/efectos de los fármacos , Infarto del Miocardio/complicaciones , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Daño por Reperfusión Miocárdica/complicaciones , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Estrés Oxidativo/efectos de los fármacos , Ratas Sprague-Dawley
6.
J Nanosci Nanotechnol ; 17(2): 1350-355, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29683630

RESUMEN

α-Fe2O3 and graphene composite (α-Fe2O3/G) was prepared by a facile one-step hydrothermal method with an aim of improving photocatalytic efficiency of the α-Fe2O3. Composition of reduced graphene oxide and α-Fe2O3 were simultaneously achieved during the hydrothermal reaction. The structures and morphologies of the composites were characterized by X-ray diffraction and transmission electron microscopy. The photoelectrochemical properties were investigated by the Mott-Schottky, electrochemical impedance spectra and UV-vis diffusion spectra measurements. The photodegradation results showed that α-Fe2O3/G composites had a much better photocatalytic performance than pure α-Fe2O3 due to extended light absorption range and lower electron­hole recombination rate. It provided a new insight into the effect of graphene on photocatalytic activity for high efficient catalysts.

7.
Exp Gerontol ; 195: 112540, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39122228

RESUMEN

BACKGROUND: Myocardial ischemia-reperfusion (MI/R) can lead to structural and functional abnormalities in the hippocampal neurons of the brain. High-mobility group box-l (HMGB1) is implicated in the activation of immune cells and the stimulation of inflammatory responses. However, the specific role of HMGB1 in cognitive impairment induced by MI/R in elderly rats has yet to be elucidated. METHODS: Elderly rats underwent surgical procedures to induce MI/R. To evaluate the learning and memory abilities of these rats, a water maze test and a new-object recognition test were administered. Nissl staining was utilised to examine hippocampal neuron damage. Enzyme-linked immunosorbent assay, western blotting, and real-time quantitative polymerase chain reaction (RT-qPCR) analyses were conducted to measure the expression levels of HMGB1, inflammatory cytokines, and molecular pathways. RESULTS: The study found that MI/R induced cognitive impairment in elderly rats. There was an observed increase in serum HMGB1 levels, along with elevated concentrations of pro-inflammatory cytokines in the plasma and hippocampus, accompanied by a decrease in anti-inflammatory cytokines. Moreover, substantial damage was evident in the hippocampal neurons of rats exposed to MI/R. In the brains of these rats, there was an increased expression of HMGB1, the receptor for advanced glycation end products (RAGE), toll-like receptor 4 (TLR4), phosphorylated p65, interleukin-1ß (IL-1ß), IL-6, IL-23, tumour necrosis factor-α (TNF-α), caspase-3, and Bax. In contrast, the expression of B-cell lymphoma 2 was decreased. The RT-qPCR analyses indicated elevated levels of HMGB1, RAGE, TLR4, IL-1ß, IL-6, IL-23, TNF-α, caspase-3, and Bax mRNA. CONCLUSION: The increased concentration of serum and hippocampal inflammatory factors in the brains of elderly rats subjected to MI/R suggests that cognitive impairment may be induced through the activation of the HMGB1/TLR4/NF-κB signalling pathway.


Asunto(s)
Disfunción Cognitiva , Citocinas , Proteína HMGB1 , Hipocampo , Daño por Reperfusión Miocárdica , Ratas Sprague-Dawley , Animales , Proteína HMGB1/metabolismo , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/etiología , Disfunción Cognitiva/patología , Masculino , Hipocampo/metabolismo , Hipocampo/patología , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Ratas , Citocinas/metabolismo , Receptor Toll-Like 4/metabolismo , Aprendizaje por Laberinto , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Modelos Animales de Enfermedad , Neuronas/metabolismo , Neuronas/patología , FN-kappa B/metabolismo , Envejecimiento , Transducción de Señal
8.
J Phys Chem Lett ; 15(23): 6031-6037, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38819116

RESUMEN

The phase of BiFeO3 (BFO) as well as its domain configuration can be tuned by strain engineering. Phase change may greatly influence the properties of the polarization field and hence charge separation. However, the photoelectrochemical properties of different BFO phases have rarely been addressed. Here, the photoelectrochemical study of tetragonal (T-) and rhombohedral (R-) phase BFO films was conducted under visible light illumination. The photocurrent density of R-BFO is 5 times that of T-BFO. A ferroelectric domain study shows that T-BFO features single domain structure in contrast to the polydomain structure of R-BFO. Higher charge separation efficiency is achieved in R-BFO, dominated by the domain walls as conducting pathways for efficient charge separation and transfer. This work provides a fundamental understanding of the photoelectrochemical properties of T- and R-BFO, offering valuable insights for the development of BFO-based materials for solar energy conversion.

9.
Medicine (Baltimore) ; 103(35): e39436, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39213208

RESUMEN

This study aimed to assess the impact of ultrasound (US)-guided nerve blocks (NBs) on anesthesia and their protective effect on pulmonary function (PF) in patients undergoing distal radius fracture (DRF) surgery. A total of 122 patients undergoing DRF surgery between April 2020 and June 2023 were included. According to the type of peripheral NB technique, these patients were randomized into a control group (CG; n = 60) receiving brachial plexus block (BPB) using blinded techniques, and an observation group (OG; n = 62) receiving US-guided supraclavicular BPB. Anesthetic effects, BPB-related indexes, adverse events, PF parameters (forced expiratory volume in 1 second, forced vital capacity, peak expiratory flow), and serum biochemical indexes (interleukin [IL]-6/10) were compared. The OG showed a relatively higher proportion of good anesthetic effects, shorter onset and completion times of block, and longer block duration compared to the CG, with a lower AE rate. Despite reductions in PF parameters and IL-10 levels after intervention, the OG maintained higher values than the CG. IL-6 levels increased significantly in the OG but remained lower than in the CG. In conclusion, US-guided NBs demonstrated significant anesthetic efficacy and apparently reduced anesthesia adverse events while also exerting a protective effect on PF in DRF surgery patients.


Asunto(s)
Fracturas del Radio , Ultrasonografía Intervencional , Humanos , Masculino , Femenino , Persona de Mediana Edad , Fracturas del Radio/cirugía , Ultrasonografía Intervencional/métodos , Bloqueo Nervioso/métodos , Anciano , Bloqueo del Plexo Braquial/métodos , Adulto , Interleucina-6/sangre , Interleucina-10/sangre , Pulmón , Pruebas de Función Respiratoria , Fracturas de la Muñeca
10.
Adv Mater ; : e2408686, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39240027

RESUMEN

Simultaneously controlling defects and film morphology at the buried interface is a promising approach to improve the power conversion efficiency (PCE) of inverted perovskite solar cells (PSCs). Here, two new donor‒acceptor type semiconductive covalent organic frameworks (COFs) are developed, COFTPA and COFICZ. The carefully designed COFs structure not only effectively regulates the morphology and defects of the buried interface film, but also realizes the alignment with the energy level of the perovskite film and enhances the extraction and transmission of the interface charge. Among them, COFICZ-treated inverted PSCs achieved a maxmum PCE of 25.68% (certified 25.14%), the inverted PCE reached a minimum PCE of 22.92% for 1 cm2 device. The efficiency of inverted PSCs with a 1.68 eV wide bandgap reached 22.92%, which is the highest datum of the reported 1.68 eV wide bandgap PSC. This lays the groundwork for the commercialization of perovskite/silicon tandem solar cells. Additionally, the unencapsulated devices demonstrated a high degree of stability during operational use and when subjected to conditions of high humidity and temperature.

11.
Adv Mater ; 35(14): e2210374, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36631722

RESUMEN

Ferroelectric materials are considered as promising photocatalysts due to their efficient charge separation via a polarization-induced built-in electric field. However, the polydomain structures hinder spatial charge separation and transfer due to the cancellation of polarization vectors in the domains. In this work, taking BiFeO3 (BFO) as a prototype, single-domain BFO nanosheets with visible-light absorption are prepared, as evident by piezoresponse force microscopy (PFM), spatially resolved surface photovoltage spectroscopy (SRSPS), and photodeposition experiments. The single-domain BFO nanosheets show nine times activity in photocatalytic water oxidation reaction under visible-light irradiation, compared with that of the polydomain BFO particles. With the asymmetric driving force for charge separation in a single domain, selective deposition of cocatalysts further enhances the photocatalytic activity of single-domain ferroelectric BFO nanosheets. These results demonstrate the role of the single-domain structure in constructing the driving force of charge separation in ferroelectric photocatalysts. The fabrication of single-domain structures in ferroelectric photocatalysts to achieve enhanced photocatalytic activity offers a path to efficiently utilize the photogenerated charges in solar energy conversion.

12.
J Pain Res ; 16: 1321-1332, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37101519

RESUMEN

Purpose: Globally, the incidence of herpes zoster (HZ) is increasing, and the resulting zoster-associated pain (ZAP) severely affects the quality of life of patients. Therefore, active treatment of ZAP and prevention of postherpetic neuralgia (PHN) are very important for patients in the early stage of the disease. This retrospective observational study aimed to evaluate the effect of CT-guided pulsed radiofrequency (PRF) combined with ozone injection on zoster-associated pain. Patients and Methods: From 2018 to 2020, 84 patients with AHN (n=28), SHN (n=32), or PHN (n=24) underwent PRF combined with ozone injection treatment after pharmacologic and conservative therapies failed. The visual analogue scale (VAS), the Pittsburgh Sleep Quality Index (PSQI), and pregabalin consumption were recorded at baseline, post-PRF, and at 1, 3, 6, and 12 months after treatment. The number of remediations performed and adverse reactions were recorded, and treatment inefficiency was calculated using a VAS score greater than 3 as the criterion. Results: The pooled results demonstrated statistically significant decreases in VAS scores, PSQI scores and consumption of pregabalin post-PRF and at 1, 3, 6, and 12 months follow-up (P<0.05). Compared with the PHN group, both the AHN and SHN groups showed clinical and statistical improvement in VAS scores and PSQI scores and in consumption of pregabalin (P< 0.05). At 1 year after the operation, the PHN group had a significantly greater number of remediation events and greater treatment inefficiency than the other two groups. No serious adverse events were observed during the procedure or during the follow-up period. Conclusion: CT-guided PRF combined with ozone injection is safe and effective for individuals with ZAP, and its short-term and long-term effects are significant. In a sense, early PRF combined with ozone injection is more effective.

13.
Nat Commun ; 13(1): 4245, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35869136

RESUMEN

Ferroelectrics are considered excellent photocatalytic candidates for solar fuel production because of the unidirectional charge separation and above-gap photovoltage. Nevertheless, the performance of ferroelectric photocatalysts is often moderate. A few studies showed that these types of photocatalysts could achieve overall water splitting. This paper proposes an approach to fabricating interfacial charge-collecting nanostructures on positive and negative domains of ferroelectric, enabling water splitting in ferroelectric photocatalysts. The present study observes efficient accumulations of photogenerated electrons and holes within their thermalization length (~50 nm) around Au nanoparticles located in the positive and negative domains of a BaTiO3 single crystal. Photocatalytic overall water splitting is observed on a ferroelectric BaTiO3 single crystal after assembling oxidation and reduction cocatalysts on the positively and negatively charged Au nanoparticles, respectively. The fabrication of bipolar charge-collecting structures on ferroelectrics to achieve overall water splitting offers a way to utilize the energetic photogenerated charges in solar energy conversion.

14.
Front Microbiol ; 11: 346, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32194535

RESUMEN

In order to improve the thermostability of lipases derived from Rhizopus chinensis, we identified lipase (Lipr27RCL) mutagenesis sites that were associated with enhanced flexibility based upon B-factor analysis and multiple sequence alignment. We found that two mutated isoforms (Lipr27RCL-K64N and Lipr27RCL-K68T) exhibited enhanced thermostability and improved residual activity, with respective thermal activity retention values of 37.88% and 48.20% following a 2 h treatment at 50°C relative to wild type Lipr27RCL. In addition, these Lipr27RCL-K64N and Lipr27RCL-K68T isoforms exhibited 2.4- and 3.0-fold increases in enzymatic half-life following a 90 min incubation at 60°C. Together these results indicate that novel mutant lipases with enhanced thermostability useful for industrial applications can be predicted based upon B-factor analysis and constructed via site-directed mutagenesis.

15.
J Mater Sci ; 52(11): 6754-6766, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28356603

RESUMEN

A novel dot-like Cu2O-loaded TiO2/reduced graphene oxide (rGO) nanoheterojunction was synthesized via UV light reduction for the first time. Cu2O with size of ca. 5 nm was deposited on rGO sheet and TiO2 nanosheets. The products were characterized by infrared spectroscopy, Raman spectrum, UV-Vis diffuse reflectance spectra, XPS techniques, photoluminescence spectra. The results demonstrated that Cu2O and rGO enhanced the absorption for solar light, separation efficiency of electron-hole pairs, charge shuttle and transfer, and eventually improved photoelectrochemical and photocatalytic performance for contaminants degradation. The reaction time and anion precursor could affect the final copper-containing phase. As extending UV irradiation time, Cu2+ was be first reduced to Cu2O and then transformed to metal Cu. In comparison with CH3COO- (copper acetate), NO3- (copper nitrate) and Cl- (copper chloride), SO42- (copper sulfate) was the optimum for synthesizing pure Cu2O phase.

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