Association of circulating omentin level and metabolic-associated fatty liver disease: a systematic review and meta-analysis.

Background: Metabolic-associated fatty liver disease (MAFLD) is closely associated with omentin, a novel adipokine that plays a vital role in metabolic balance. The literature about the relationship between circulating omentin and MAFLD is conflicting. Therefore, this meta-analysis evaluated circulating omentin levels in patients with MAFLD compared with healthy controls to explore the role of omentin in MAFLD. Methods: The literature search was performed up to April 8, 2022, using PubMed, Cochrane Library, EMBASE, CNKI, Wanfang, CBM, Clinical Trials Database and Grey Literature Database. This meta-analysis pooled the statistics in Stata and presented the overall results using the standardized mean difference (SMD) and 95% confidence interval (CI). Results: Twelve studies with 1624 individuals (927 cases and 697 controls) were included, and all of them were case-control studies. In addition, ten of twelve included studies were conducted on Asian participants. Patients with MAFLD had significantly lower circulating omentin levels than healthy controls (SMD=-0.950 [-1.724, -0.177], P=0.016). Subgroup analysis and meta-regression demonstrated that fasting blood glucose (FBG) might be the source of heterogeneity and was inversely associated with omentin levels (coefficient=-0.538, P=0.009). No significant publication bias existed (P>0.05), and outcomes were robust in the sensitivity analysis. Conclusion: Lower circulating omentin levels were associated with MAFLD, and FBG might be the source of heterogeneity. Since Asian studies accounted for a significant portion of the meta-analysis, the conclusion might be more applicable to the Asian population. By investigating the relationship between omentin and MAFLD, this meta-analysis laid the foundation for the development of diagnostic biomarkers and treatment targets. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022316369.

Graphene-Based Moisture Actuator with Oriented Microstructures Prepared by One-Step Laser Reduction for Accurately Controllable Responsive Direction and Position.

Actuators with fast and precise controllable responses are highly in demand for implementing agilely accurate mechanical movements in smart robots, intelligent sensors, biomimetic devices, and so on. Here, we report a graphene-based moisture actuator with accurately controllable direction and position responses achieved by a fast, controlled, and even programmable one-step laser reduction method. The laser reduction-induced oriented microstructures help to precisely guide the direction and location of the moisture response in graphene-based Janus films. The excellent moisture-mechanical response behaviors in these novel moisture actuators originate from the Janus structures and the periodic microstructures of a line-scanned layer. Our customized complex intelligent devices such as drums, bands, and three-dimensional wave humidity drives can highly match and verify the finite element simulations, which will inspire the creation of further smart robot designs for accurate deformation.

Bio-Inspired High Sensitivity of Moisture-Mechanical GO Films with Period-Gradient Structures.

Moisture actuators can accomplish humidity-triggered energy-conversion process, through material screening and structural design. Inspired by natural caterpillars and the hydrophilic properties of graphene oxide (GO), this work proposes a geometrical design of period-gradient structures in GO films for fabricating moisture actuators. These novel period-gradient-structured GO films exhibit excellent dynamic performance that they could deform at 1000° with a small radius in several seconds at a high relative humidity (RH ≈ 80%). The properties of fast actuating speed and high response to deformation are achieved through the structural designing of the sole GO film by a one-step formation process. A mechanics-based theoretical model combined with the finite element simulation is presented to demonstrate the actuating mechanism in geometry, moisture, and mechanics, which lays the foundation for potential applications of GO films in remote control, environmental monitoring, and man-machine interactions.

Nonfullerene Ternary Organic Solar Cell with Effective Charge Transfer between Two Acceptors.

High power conversion efficiency can be realized by using a ternary bulk heterojunction with complementary absorption spectra in organic solar cells. However, as the development of nonfullerene acceptors with a broad absorption spectrum makes the absorption efficiency of the photovoltaic devices close to optimal, such a strategy needs modifying. In particular, charge transfer between the two acceptors is necessary to be considered. Herein, we purposely design a ternary system based on PTB7-Th:COi8DFIC:ITIC-4F. Though the presence of ITIC-4F in PTB7-Th:COi8DFIC could not broaden the absorption spectrum obviously, the formed cascade-energy-level alignment is beneficial for promoting and balancing exciton separation and charge transport between the donor and two acceptors and even between the acceptors. Insights into the charge transport route in the completed system are provided via using the techniques including photoluminescence spectroscopy and pump-probe photoconductivity spectroscopy. This work provides a new idea for designing highly efficient ternary organic solar cells.

Optimizing the component ratio of PEDOT:PSS by water rinse for high efficiency organic solar cells over 16.7.

For the state-of-the-art organic solar cells (OSCs), PEDOT:PSS is the most popularly used hole transport material for the conventional structure. However, it still suffers from several disadvantages, such as low conductivity and harm to ITO due to the acidic PSS. Herein, a simple method is introduced to enhance the conductivity and remove the additional PSS by water rinsing the PEDOT:PSS films. The photovoltaic devices based on the water rinsed PEDOT:PSS present a dramatic improvement in efficiency from 15.98% to 16.75% in comparison to that of the untreated counterparts. Systematic characterization and analysis reveal that although part of the PEDOT:PSS is washed away, it still leaves a smoother film and the ratio of PEDOT to PSS is higher than before in the remaining films. It can greatly improve the conductivity and reduce the damage to substrates. This study demonstrates that finely modifying the charge transport materials to improve conductivity and reduce defeats has great potential for boosting the efficiency of OSCs.

A wrinkled structure with broadband and omnidirectional light-trapping abilities for improving the performance of organic solar cells with low defect density.

Fabricating thin film solar cells on the light-trapping structures is an effective way to improve the absorption of the active layer. Here, we report a non-fullerene organic solar cell based on a PBDB-T:ITIC active layer, a wrinkled metal rear electrode, and a MoO3/Ag/ZnS front transparent electrode. Optical characterization shows that the wrinkled metal structure can remarkably increase the absorption of the active layer in a broadband range. The resulting device shows a power conversion efficiency of 8.2%, which increases by 4.6% compared to that of the flat counterpart. Apart from higher absorption, the improved performance can also be ascribed to the efficient charge transport and collection in the device due to the lower defect density, larger interfacial area, and smaller active layer thickness. A device with a power conversion efficiency of 10.19% based on the flat ITO/glass substrate is also achieved. Accordingly, a power conversion efficiency of about 10.66% is predicted under the condition where the wrinkled rear electrode and the ITO front electrode are employed. In addition, the power conversion efficiency of the wrinkled device could increase by about 50.48% compared to that of the flat device under an incident angle of 60 °C, illustrating that a better omnidirectional ability is achieved.

Insights into Charge Separation and Transport in Ternary Polymer Solar Cells.

Although ternary polymer solar cells have more potential in realizing a high power conversion efficiency than the binary counterparts, the mechanism of exciton separation and charge transport in such complicated ternary systems is far from being understood. Herein, we focus on this issue and give a clear view on the detailed roles of the ternary components contributing to the device performance, through utilizing the technique of pump-probe photoconductivity spectroscopy combined with transient photoluminescence spectroscopy, for the first time for ternary polymer solar cells. The ternary photovoltaic devices are based on PBDB-T:ITIC:PC71BM and present a dramatic improvement in efficiency in comparison to that of the binary counterparts. Systematic investigation reveals that the excitons generated in ITIC could be separated at the interface of PBDB-T:ITIC rather than ITIC:PC71BM with holes injecting to PBDB-T. These holes together with those generated in PBDB-T contribute to the photocurrent of the devices. The aggregation of holes in PBDB-T would also weaken the exciton generation herein, and the electron injection to PC71BM and ITIC would also be influenced. The key role of PC71BM in the ternary devices is accepting the electrons from PBDB-T and transporting them to the cathode with a higher rate than that of ITIC. Thus, this article is of importance in constructing high-efficiency ternary polymer solar cells.