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1.
Adv Mater ; : e2313673, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503278

RESUMO

Organic-inorganic hybrid perovskites have emerged as highly promising candidates for photovoltaic applications, owing to the exceptional optoelectronic properties and low cost. Nonetheless, the performance and stability of solar cells suffer from the defect states of perovskite films aroused by non-optically active phases and non-centralized crystal orientation. Herein, a versatile organic molecule, Hydantoin, to modulate the crystallization of perovskite, is developed. Benefiting from the diverse functional groups, more spatially oriented perovskite films with high crystallinity are formed. This enhancement is accompanied by a conspicuous reduction in defect density, yielding efficiency of 25.66% (certified 25.15%), with superb environmental stability. Notably, under the standard measurement conditions (ISOS-L-1I), the maximum power point (MPP) output maintains 96.8% of the initial efficiency for 1600 h and exhibits excellent ion migration suppression. The synergistic regulation of crystallization and spatial orientation offers novel avenues for propelling perovskite solar cell (PSC) development.

2.
Sensors (Basel) ; 24(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38339751

RESUMO

To address the complexities, inflexibility, and security concerns in traditional data sharing models of the Industrial Internet of Things (IIoT), we propose a blockchain-based data sharing and privacy protection (BBDSPP) scheme for IIoT. Initially, we characterize and assign values to attributes, and employ a weighted threshold secret sharing scheme to refine the data sharing approach. This enables flexible combinations of permissions, ensuring the adaptability of data sharing. Subsequently, based on non-interactive zero-knowledge proof technology, we design a lightweight identity proof protocol using attribute values. This protocol pre-verifies the identity of data accessors, ensuring that only legitimate terminal members can access data within the system, while also protecting the privacy of the members. Finally, we utilize the InterPlanetary File System (IPFS) to store encrypted shared resources, effectively addressing the issue of low storage efficiency in traditional blockchain systems. Theoretical analysis and testing of the computational overhead of our scheme demonstrate that, while ensuring performance, our scheme has the smallest total computational load compared to the other five schemes. Experimental results indicate that our scheme effectively addresses the shortcomings of existing solutions in areas such as identity authentication, privacy protection, and flexible combination of permissions, demonstrating a good performance and strong feasibility.

3.
Sensors (Basel) ; 23(18)2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37765967

RESUMO

Simultaneous localization and mapping (SLAM) algorithms are widely applied in fields such as autonomous driving and target tracking. However, the effect of moving objects on localization and mapping remains a challenge in natural dynamic scenarios. To overcome this challenge, this paper proposes an algorithm for dynamic point cloud detection that fuses laser and visual identification data, the multi-stage moving object identification algorithm (MoTI). The MoTI algorithm consists of two stages: rough processing and precise processing. In the rough processing stage, a statistical method is employed to preliminarily detect dynamic points based on the range image error of the point cloud. In the precise processing stage, the radius search strategy is used to statistically test the nearest neighbor points. Next, visual identification information and point cloud registration results are fused using a method of statistics and information weighting to construct a probability model for identifying whether a point cloud cluster originates from a moving object. The algorithm is integrated into the front-end of the LOAM system, which significantly improves the localization accuracy. The MoTI algorithm is evaluated on an actual indoor dynamic environment and several KITTI datasets, and the results demonstrate its ability to accurately detect dynamic targets in the background and improve the localization accuracy of the robot.

4.
Sensors (Basel) ; 23(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37430600

RESUMO

This paper is concerned with the problem of state estimation for nonlinear multi-sensor systems with cross-correlated noise and packet loss compensation. In this case, the cross-correlated noise is modeled by the synchronous correlation of the observation noise of each sensor, and the observation noise of each sensor is correlated with the process noise at the previous moment. Meanwhile, in the process of state estimation, since the measurement data may be transmitted in an unreliable network, data packet dropout will inevitably occur, leading to a reduction in estimation accuracy. To address this undesirable situation, this paper proposes a state estimation method for nonlinear multi-sensor systems with cross-correlated noise and packet dropout compensation based on a sequential fusion framework. Firstly, a prediction compensation mechanism and a strategy based on observation noise estimation are used to update the measurement data while avoiding the noise decorrelation step. Secondly, a design step for a sequential fusion state estimation filter is derived based on an innovation analysis method. Then, a numerical implementation of the sequential fusion state estimator is given based on the third-degree spherical-radial cubature rule. Finally, the univariate nonstationary growth model (UNGM) is combined with simulation to verify the effectiveness and feasibility of the proposed algorithm.

5.
Angew Chem Int Ed Engl ; 62(15): e202300314, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36788422

RESUMO

Hole transport materials (HTMs) with high hole mobility, good band alignment and ease of fabrication are highly desirable for perovskite solar cells (PSCs). Here, we designed and synthesized novel organic HTMs, named T3, which can be synthesized in high yields with commercially available materials, featuring a substituted pyrrole core and triphenylamine peripheral arms. The capability of functionalization in the final synthetic step provides an efficient way to obtain a variety of T3-based HTMs with tunable energy levels and other properties. Among them, fluorine-substituted T3 (T3-F) exhibits the best band alignment and hole extraction properties, leading to PSCs with outstanding PCEs of 24.85 % and 24.03 % (certified 23.46 %) for aperture areas of 0.1 and 1 cm2 , respectively. The simple structure and tunable performance of T3 can inspire further optimization for efficient PSCs.

7.
Adv Mater ; 35(13): e2205027, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36681866

RESUMO

Organic-inorganic hybrid perovskites exhibit outstanding performances in perovskite solar cells (PSCs). However, the complex solution chemistry of perovskites precursors renders it difficult to prepare large-area devices in a reproducible way, which is a prerequisite for the technology to make an impact beyond lab scale. Vacuum processing, instead, is an established technology for large-scale coating of thin films. However, with respect to the hybrid perovskites it is highly challenging due to the high vapor pressure of the organic ammonium halide. In this work, vacuum evaporation of lead iodide and solution processing of organic ammonium halide is combined to produce large-area homogeneous perovskite films with large grains in a highly reproducible way. The resulting PSCs achieve a power conversion efficiency (PCE) of 24.3% (certified 23.9%) on small area (0.10 cm2 ), 24.0% (certified 23.7%) on large area (1 cm2 ) and 20.0% for minimodule (16 cm2 ), and maintain 90% of its initial efficiency after 1000 h 1-sun operation. The vacuum evaporation prevents advert environmental effects on lead halide formation and guarantees a reproducible fabrication of high-quality large-area perovskite films, which opens a promising way for large-scale fabrication of perovskite optoelectronics.

8.
Nanomicro Lett ; 15(1): 12, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36512180

RESUMO

Perovskite solar cells (PSCs) have become the representatives of next generation of photovoltaics; nevertheless, their stability is insufficient for large scale deployment, particularly the reverse bias stability. Here, we propose a transparent conducting oxide (TCO) and low-cost metal composite electrode to improve the stability of PSCs without sacrificing the efficiency. The TCO can block ion migrations and chemical reactions between the metal and perovskite, while the metal greatly enhances the conductivity of the composite electrode. As a result, composite electrode-PSCs achieved a power conversion efficiency (PCE) of 23.7% (certified 23.2%) and exhibited excellent stability, maintaining 95% of the initial PCE when applying a reverse bias of 4.0 V for 60 s and over 92% of the initial PCE after 1000 h continuous light soaking. This composite electrode strategy can be extended to different combinations of TCOs and metals. It opens a new avenue for improving the stability of PSCs.

9.
Oncol Rep ; 48(6)2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36222297

RESUMO

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that certain of the western blot data shown in Figs. 4B and 7, the stratch­wound assay data shown in Figs. 2B and E and Fig. 6B, and the cellular images shown in Fig. 3 were strikingly similar to data appearing in different form in other articles written by different authors in different research institutions. Owing to the fact that the contentious data in the above article had already been published elsewhere prior to its submission to Oncology Reports, the Editor has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [Oncology Reports 38: 1075­1082, 2017; DOI: 10.3892/or.2017.5781].

10.
PLoS One ; 17(10): e0274092, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36288268

RESUMO

This study examines urban innovation activities from the perspective of improving the efficiency of innovation chains and explored their operational patterns. The connotation of the urban innovation chain was analyzed following the process of the innovation chain and the characteristics of urban innovation activities. The urban innovation chain can be divided into the following three stages: original, technological, and innovation transformation. An indicator system for evaluating the three capacities of the urban innovation chain was established. Furthermore, the development level of strategic emerging industries was used as an indicator to measure the chain's efficiency and analyze the relationship between these three constructed capacities in Chinese national innovative cities. Data published on the national innovative cities were used to measure the capacity of the urban innovation chain. The development of Strategic emerging industries indicates cities' innovation performance, and an inductive approach was applied to analyze the relationship between the capacity construction of the urban innovation chain and innovation performance in innovative cities. This study found that the capacity of the urban innovation chain positively affected urban innovation performance and that the balanced development of the three capacities positively affected urban innovation performance. When urban innovation performance was at its highest, the contribution of original innovation capacity to innovation performance was significantly greater than that of the other two capacities; thus, an inverted U-curve illustrates the relationship between the improvement of urban innovation performance and the balance of the three capacities of the urban innovation chain. This study's conclusions enrich the relevant theories of the innovation chain, provide a reference for the construction of the urban innovation chain, and promote the development of Strategic emerging industries.


Assuntos
Eficiência , Indústrias , Cidades , China , Desenvolvimento Econômico
11.
ACS Appl Mater Interfaces ; 14(38): 43917-43925, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36107732

RESUMO

Lithium metal batteries have become potential high-energy storage devices because lithium metal has excellent theoretical capacity and low reduction potential. Unfortunately, the reckless growth of lithium dendrites leads to the decrease in Coulombic efficiency and the attenuation of cycle performance. Herein, we propose a collaborative assembly approach for a fluorine-enriched heterostructured solid electrolyte interphase (SEI) on lithium metal to enable stable and ultralong-life lithium metal batteries. The fluorine-enriched heterostructured SEI consists of an artificial precursor substrate K2ZrF6 and an epigenetically assembled LiF layer, and the composite structure cooperatively realizes the rapid conduction of Li+ ions and inhibits the formation of lithium dendrites. Benefiting from the heterostructured SEI, the symmetric cell exhibits an ultralong-time stable cycle of more than 7000 h at a high current and capacity density (4 mA cm-2 and 4 mA h cm-2, respectively), much longer than that of the lithium cell. Besides, the LiFePO4 full battery (LFP||Li-Zr) enables substantially enhanced cyclability over 800 cycles at 1 C. This work paves the way for dendrite-free and long-life lithium metal batteries with well-balanced heterostructured SEI engineering.

12.
Innovation (Camb) ; 3(6): 100310, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36160942

RESUMO

Flexible perovskite solar cells (FPSCs) have emerged as power sources in versatile applications owing to their high-efficiency characteristics, excellent flexibility, and relatively low cost. Nevertheless, undesired strain in perovskite films greatly impacts the power-conversion efficiency (PCE) and stability of PSCs, particularly in FPSCs. Herein, a novel multifunctional organic salt, methylammonium succinate, which can alleviate strain and reinforce grain boundaries, was incorporated into the perovskite film, leading to relaxed microstrain and a lower defect concentration. As a result, a PCE of 25.4% for rigid PSCs and a record PCE of 23.6% (certified 22.5%) for FPSCs have been achieved. In addition, the corresponding FPSCs exhibited excellent bending durability, maintaining ∼85% of their initial efficiency after bending at a 6 mm radius for 10 000 cycles.

13.
Sci Adv ; 8(28): eabo7422, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35857518

RESUMO

Vacuum evaporation is promising for the high-throughput fabrication of perovskite solar cells (PSCs) because of its solvent-free characteristic, precise control of film thickness, and compatibility with large-scale production. Nevertheless, the power conversion efficiency (PCE) of PSCs fabricated by vacuum evaporation lags behind that of solution-processed PSCs. Here, we report a Cl-containing alloy-mediated sequential vacuum evaporation approach to fabricate perovskite films. The presence of Cl in the alloy facilitates organic ammonium halide diffusion and the subsequent perovskite conversion reaction, leading to homogeneous pinhole-free perovskite films with few defects. The resulting PSCs yield a PCE of 24.42%, 23.44% (certified 22.6%), and 19.87% for 0.1, 1.0, and 14.4 square centimeters (mini-module, aperture area), respectively. The unencapsulated PSCs show good stability with negligible decline in performance after storage in dry air for more than 4000 hours. Our method provides a reproducible approach for scalable fabrication of large-area, high-efficiency PSCs and other perovskite-based optoelectronics.

14.
Cell Death Dis ; 13(5): 512, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35641492

RESUMO

Atherosclerosis is a maladaptive chronic inflammatory disease, which remains the leading cause of death worldwide. The NLRP3 inflammasome constitutes a major driver of atherosclerosis, yet the mechanism of action is poorly understood. Mitochondrial dysfunction is essential for NLRP3 inflammasome activation. However, whether activated NLRP3 inflammasome exacerbates mitochondrial dysfunction remains to be further elucidated. Herein, we sought to address these issues applying VX765, a well-established inhibitor of caspase 1. VX765 robustly restrains caspase 1-mediated interleukin-1ß production and gasdermin D processing. Our study assigned VX765 a novel role in antagonizing NLRP3 inflammasome assembly and activation. VX765 mitigates mitochondrial damage induced by activated NLRP3 inflammasome, as evidenced by decreased mitochondrial ROS production and cytosolic release of mitochondrial DNA. VX765 blunts caspase 1-dependent cleavage and promotes mitochondrial recruitment and phosphorylation of Parkin, a key mitophagy regulator. Functionally, VX765 facilitates mitophagy, efferocytosis and M2 polarization of macrophages. It also impedes foam cell formation, migration and pyroptosis of macrophages. VX765 boosts autophagy, promotes efferocytosis, and alleviates vascular inflammation and atherosclerosis in both ApoE-/- and Ldlr-/- mice. However, these effects of VX765 were abrogated upon ablation of Nlrp3 in ApoE-/- mice. This work provides mechanistic insights into NLRP3 inflammasome assembly and this inflammasome in dictating atherosclerosis. This study highlights that manipulation of caspase 1 paves a new avenue to treatment of atherosclerotic cardiovascular disease.


Assuntos
Aterosclerose , Inibidores de Caspase , Inflamassomos , Mitofagia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Aterosclerose/tratamento farmacológico , Caspase 1 , Inibidores de Caspase/farmacologia , Camundongos , Camundongos Knockout para ApoE , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética
15.
Int J Gen Med ; 14: 733-739, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33688244

RESUMO

BACKGROUND: Previous studies have reported that patients with stroke have a high incidence of cognitive decline. The aim was to elucidate the association between serum E-selectin levels and cognitive function in stroke patients. MATERIALS AND METHODS: Serum levels of E-selectin were measured in 322 patients with stroke at baseline. Cox proportional hazard analysis was used to evaluate the predictive value of serum E-selectin for predicting cognitive decline (end point) in patients with stroke. RESULTS: Multivariate linear regression analysis revealed that serum E-selectin levels were independently associated with MOCA score after adjusting for age, gender, BMI, current smoker, current drinker, admission systolic and diastolic BP, CVD history and laboratory measurements in patients with stroke at baseline (Sß= -0.156; 95% CI, - 0.170- - 0.074; P<0.001). The multivariate Cox proportional hazard analysis revealed that serum E-selectin (HR=2.481, 95% CI 1.533-4.327, P-trend <0.001) was an independent prognostic factor for cognitive decline in these patients with stroke during the follow-up period. CONCLUSION: Our results showed that increased serum E-selectin levels were significantly and independently associated with cognitive decline and had independent predictive value for cognitive decline in patients with stroke. Serum E-selectin might enable early recognition of cognitive decline among stroke patients.

16.
ISA Trans ; 114: 150-170, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33419570

RESUMO

This paper studies the fixed-time stability of attitude coordination control for spacecraft formation flying (SFF) in the presence of some external disturbance. Firstly, to ensure that the states converge to the origin within a fixed time, a novel nonsingular terminal sliding mode surface (NTSMS) is designed. The convergence time is bounded by some predefined constants. Secondly, an attitude synchronization controller is proposed based on the designed NTSMS, which guarantees the fixed-time stability of SFF under an undirected communication topology. Finally, a fixed-time adaptive control law is designed for cases in which the boundary of the external disturbance is unknown. The fixed-time stability is guaranteed by a revised form of the proposed NTSMS. Simulation results show that the proposed controllers provide fixed-time stability and outperform existing finite-time controllers.

17.
Adv Mater ; 32(21): e2000865, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32285563

RESUMO

Excess lead iodide (PbI2 ), as a defect passivation material in perovskite films, contributes to the longer carrier lifetime and reduced halide vacancies for high-efficiency perovskite solar cells. However, the random distribution of excess PbI2 also leads to accelerated degradation of the perovskite layer. Inspired by nanocrystal synthesis, here, a universal ligand-modulation technology is developed to modulate the shape and distribution of excess PbI2 in perovskite films. By adding certain ligands, perovskite films with vertically distributed PbI2 nanosheets between the grain boundaries are successfully achieved, which reduces the nonradiative recombination and trap density of the perovskite layer. Thus, the power conversion efficiency of the modulated device increases from 20% to 22% compared to the control device. In addition, benefiting from the vertical distribution of excess PbI2 and the hydrophobic nature of the surface ligands, the modulated devices exhibit much longer stability, retaining 72% of their initial efficiency after 360 h constant illumination under maximum power point tracking measurement.

18.
Oncol Rep ; 38(2): 1075-1082, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28677798

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of malignant pancreatic tumor. MicroRNAs (miRNAs) are a group of small, non-protein coding, endogenous RNAs that play critical roles in tumorigenesis and progression of PDAC. In the present study, we demonstrated that miR-448 expression was downregulated in PDAC tissues and cell lines. Clinical association analysis indicated that low expression of miR-448 was associated with poor prognostic features and conferred a significant reduced survival of PDAC patients. Overexpression of miR-448 suppressed PDAC cell migration and invasion, while its loss showed the opposite effects on these cellular processes. In vivo experiments revealed that miR-488 restoration prohibited liver metastasis of PDAC in nude mice. Moreover, we found that Janus kinase 1 (JAK1) was a direct target gene of miR-448 in PDAC cells. We further demonstrated that the expression of JAK1 mRNA was upregulated in PDAC tissues. Notably, the expression of JAK1 mRNA was inversely correlated with the level of miR-448 in PDAC tissues. In addition, JAK1 knockdown showed similar effects of miR-448 on the metastasis of PDAC cells. JAK1/STAT3 pathway may be involved in the function of miR-448 in PDAC cells. Taken together, these findings suggest that miR-448 functions as a tumor suppressor in the development of PDAC through targeting the JAK1/STAT3 pathway.


Assuntos
Adenocarcinoma/prevenção & controle , Carcinoma Ductal Pancreático/prevenção & controle , Janus Quinase 1/antagonistas & inibidores , Neoplasias Hepáticas/prevenção & controle , MicroRNAs/genética , Neoplasias Pancreáticas/prevenção & controle , Fator de Transcrição STAT3/antagonistas & inibidores , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/secundário , Animais , Apoptose , Biomarcadores Tumorais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/secundário , Estudos de Casos e Controles , Movimento Celular , Proliferação de Células , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Janus Quinase 1/genética , Janus Quinase 1/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Metástase Linfática , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Prognóstico , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
19.
BMC Cardiovasc Disord ; 15: 116, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26446519

RESUMO

BACKGROUND: Oxidative stress is closely associated with cardiac fibrosis. However, the effect of copper, zinc-superoxide dismutase (SOD1) as a therapeutic agent is limited due to the insufficient transduction. This study was aimed to investigate the effect of PEP-1-SOD1 fusion protein on angiotensin II (ANG II)-induced collagen metabolism in rat cardiac myofibroblasts (MCFs). METHODS: MCFs were pretreated with SOD1 or PEP-1-SOD1 fusion protein for 2 h followed by incubation with ANG II for 24 h. Cell proliferation was measured by Cell Counting Kit-8. Superoxide anion productions were detected by both fluorescent microscopy and Flow Cytometry. MMP-1 and TIMP-1 were determined by ELISA. Intracellular MDA content and SOD activity were examined by commercial assay kits. Protein expression was analyzed by western blotting. RESULTS: PEP-1-SOD1 fusion protein efficiently transduced into MCF, scavenged intracellular O2 (-), decreased intracellular MDA content, increased SOD activity, suppressed ANG II-induced proliferation, reduced expression of TGF-ß1, α-SMA, collagen type I and III, restored MMP-1 secretion, and attenuated TIMP-1 secretion. CONCLUSION: PEP-1-SOD1 suppressed MCF proliferation and differentiation and reduced production of collagen type I and III. Therefore, PEP-1-SOD1 fusion protein may be a potential novel therapeutic agent for cardiac fibrosis.


Assuntos
Colágeno Tipo III/metabolismo , Colágeno Tipo I/metabolismo , Cisteamina/análogos & derivados , Miofibroblastos/metabolismo , Peptídeos/farmacologia , Superóxido Dismutase/farmacologia , Angiotensina II , Animais , Proliferação de Células/efeitos dos fármacos , Cisteamina/farmacologia , Masculino , Malondialdeído/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Superóxido Dismutase-1 , Superóxidos/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo
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