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1.
Hepatology ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39028901

RESUMEN

BACKGROUND AND AIMS: The liver possesses a remarkable regenerative capacity in response to injuries or viral infections. Various growth factors and cytokines are involved in regulating liver regeneration. Prostaglandin D 2 , a pro-resolution lipid mediator, is the most abundant hepatic prostanoid. However, the role of prostaglandin D 2 in the injury-induced liver regeneration remains unclear. APPROACH AND RESULTS: Two-thirds partial hepatectomy (70% PH), massive hepatectomy (85% resection), and carbon tetrachloride-induced chronic injury were performed in mice to study the mechanisms of live regeneration. Hepatic prostaglandin D 2 production was elevated in mice after PH. Global deletion of D prostanoid receptor (DP) 1, but not DP2, slowed PH-induced liver regeneration in mice, as evidenced by lower liver weight to body weight ratio, less Ki67 + hepatocyte proliferation, and G2/M phase hepatocytes. In addition, DP1 deficiency, specifically in resident KCs, and not in endothelial cells or HSCs, retarded liver regeneration in mice after PH. Conversely, the overexpression of exogenous DP1 in KCs accelerated liver regeneration in mice. Mechanistically, DP1 activation promoted Wnt2 transcription in a PKA/CREB-dependent manner in resident KCs and mediated hepatocyte proliferation through Frizzled8/ß-catenin signaling. Adeno-associated virus vector serotype 8-mediated Frizzled8 knockdown in hepatocytes attenuated accelerated liver regeneration in KC-DP1 transgenic mice after PH. Treatment with the DP1 receptor agonist BW245C promotes PH-induced liver regeneration in mice. CONCLUSIONS: DP1 activation mediates crosstalk between KCs and hepatocytes through Wnt2 and facilitates liver regeneration. Hence, DP1 may serve as a novel therapeutic target in acute and chronic liver diseases.

2.
Opt Lett ; 49(6): 1413-1416, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38489413

RESUMEN

Tunable optical filters at the chip scale play a crucial role in fulfilling the need for reconfigurability in channel routing, optical switching, and wavelength division multiplexing systems. In this Letter, we propose a tunable double notch filter on thin-film lithium niobate using dual microring architecture. This unique integrated filter is essential for complex photonic integrated circuits, along with multiple channels and various frequency spacing. With only one loaded voltage, the device demonstrates a wide frequency spacing tunability from 16.1 to 89.9 GHz by reversely tuning the resonances of the two microrings while the center wavelength between the two resonances remains unaltered. Moreover, by utilizing the pronounced electro-optic properties of lithium niobate associated with the tight light confined nanophotonic waveguides, the device demonstrates a spacing tunability of 0.82 GHz/V and a contrast of 10-16 dB. In addition, the device has an ultracompact footprint of 0.0248 mm2.

3.
Nanotechnology ; 35(42)2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39025078

RESUMEN

Flexible electronic device requires a novel micro-supercapacitors (MSCs) energy conversion-storage system based on two-dimensional (2D) materials to solve the problems of stiffness and complexity. Herein, we report a novel catalytic introduction method of graphene with adjustable porosity by high-energy photon beam. The graphene/Ti3C2Txheterostructure was constructed by electrostatic self-assembly, has a high cycle life (98% after 8000 cycles), energy density (11.02 mWh cm-3), and demonstrate excellent flexible alternating current line-filtering performance. The phase angle of -79.8° at 120 Hz and a resistance-capacitance constant of 0.068 ms. Furthermore, the porous graphene/Ti3C2Txstructures produced by multiple catalytic inductions allowed ions to deeply penetrate the electrode, thereby increasing the stacking density. The special 'pore-layer nesting' graphene structure with adjustable pores effectively increased the specific surface area, and its superior matching with electrolyte solutions greatly improved surface-active site utilization. This work offers an alternative strategy for fabricating a 2D heterostructure for an MSC.

4.
Phys Chem Chem Phys ; 26(26): 18302-18310, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38910568

RESUMEN

This study introduces a new wide-bandgap graphene-like structure, denoted as C6BN, achieved by incorporating an eight-electron BN pair, substantially modifying its electronic properties. Utilizing extensive density functional calculations, we comprehensively analyzed the stability, electronic structure, mechanical properties, and optical-electrical characteristics of C6BN. Our investigations reveal the material's exceptional thermodynamic, mechanical, and dynamic stability. Notably, the calculated wide bandgap of 2.81 eV in C6BN, supported by analyses of energy levels, band structures, and density of states, positions it as a promising two-dimensional wide-bandgap semiconductor. Additionally, C6BN exhibits isotropic mechanical features, highlighting its inherent flexibility. Remarkably, our calculations indicate an ultra-low dielectric constant (k = 1.67) for C6BN, surpassing that of well-established third-generation semiconductors. Further exploration into the thermoelectric properties of C6BN demonstrates its promising performance, as evidenced by calculations of thermal conductivity (κ), power factor (P), and Seebeck coefficient (S). In summary, our findings underscore the significant potential of the proposed C6BN structure as a flexible two-dimensional material poised to drive future advancements in electronic and energy-related technologies.

5.
J Chem Phys ; 161(12)2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39324533

RESUMEN

It is still critical to prepare a high-quality absorber layer for high-performance Cu2ZnSnSe4 (CZTSe) multi-component thin film solar cell. The gas pressure during the selenization process is commonly referred to as the pressure of inert gas in the tube furnace, while the exact selenium partial pressure is difficult to be controlled. Therefore, the grain growth under different selenium partial pressures cannot be made clear, and the film quality cannot be controlled as well. In this work, we use a sealed quartz tube as the selenization vessel, which can provide a relatively high and controllable selenium partial pressure during the selenization process. To further tailor the grain growth, lithium doping is also utilized. We find that lithium can greatly promote the growth of CZTSe films as the selenium partial pressure is controlled near the selenium saturation vapor pressure. Combined with ALD-Al2O3, the crystallization quality of CZTSe absorber films is significantly enhanced and the efficiency of CZTSe solar cells achieved a significant improvement. This work clarifies the effect of controllable Se pressure on CZTSe film growth and can lead to better results in CZTSe and other multi-compound thin film solar cells.

6.
Artículo en Inglés | MEDLINE | ID: mdl-38819176

RESUMEN

Objective: To explore the efficacy of dapagliflozin plus pentoxifylline in the treatment of early diabetic nephropathy and its effect on serum inflammatory factors and immune function. Methods: A total of 90 patients with early diabetic nephropathy who were admitted to Cangzhou Central Hospital from January 2019 to January 2022 were recruited and randomized (1:1) into a control group and an observation group using the random number table method. The control group was treated with dapagliflozin, and the observation group was treated with pentoxifylline plus dapagliflozin. The effectiveness of urinary α (1) microglobulin (α 1-mg) was determined by immunoturbidimetric method, and urinary ß (2) microglobulin (ß 2-mg) was determined. Urine creatinine was determined enzymatically, and the urinary microprotein albumin creatinine ratio (mAlb/Cr) was calculated. The levels of inflammatory factors [interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)] were detected. Before and after treatment, 3 mL of venous blood was drawn from the two groups of patients, and serum CD4+, CD8+, and CD4+/CD8+ levels were detected. The incidence of adverse reactions between the two groups was calculated. Results: Dapagliflozin plus pentoxifylline was associated with a higher effective rate than dapagliflozin alone (96.67% vs 81.67%) (RR 0·80 [95% CI 0·61-0.98]; P = .021). Dapagliflozin plus pentoxifylline led to lower renal function parameters versus dapagliflozin alone, in favor of the observation group (RR 0.67 [95% CI 0.66-0.88]; P = .032). After treatment, the serum levels of IL-6 and TNF-α in patients treated with dapagliflozin plus pentoxifylline were lower than counterparts treated with dapagliflozin (RR 0.62 [95% CI 0.51-0.78]; P = .037). After treatment, CD4+ and CD4+/CD8+ in the two groups were increased compared with baseline parameters, and the level of CD8+ was decreased ; the increase and decrease were greater in the observation group than in the control group (RR 0.70 [95% CI 0.71-0.96]; P = .044) (RR 0.53 [95% CI 0.41-0.78]; P = .033). The two groups demonstrated similar safety profiles with no statistical difference observed in the incidence of adverse reactions between the two groups (RR 0.73 [95% CI 0.73-1.08]; P = .051). Conclusion: Dapagliflozin plus pentoxifylline might be a promising alternative in the treatment of patients with early diabetic nephropathy, it significantly mitigates the body's inflammatory response, enhances immune function, attenuates the main clinical symptoms, with a high safety profile.

7.
Sensors (Basel) ; 24(12)2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38931658

RESUMEN

This article describes a novel fusion of a generative formal model for three-dimensional (3D) shapes with deep learning (DL) methods to understand the geometric structure of 3D objects and the relationships between their components, given a collection of unorganized point cloud measurements. Formal 3D shape models are implemented as shape grammar programs written in Procedural Shape Modeling Language (PSML). Users write PSML programs to describe complex objects, and DL networks estimate the configured free parameters of the program to generate 3D shapes. Users write PSML programs to enforce fundamental rules that define an object class and encode object attributes, including shapes, components, size, position, etc., into a parametric representation of objects. This fusion of the generative model with DL offers artificial intelligence (AI) models an opportunity to better understand the geometric organization of objects in terms of their components and their relationships to other objects. This approach allows human-in-the-loop control over DL estimates by specifying lists of candidate objects, the shape variations that each object can exhibit, and the level of detail or, equivalently, dimension of the latent representation of the shape. The results demonstrate the advantages of the proposed method over competing approaches.

8.
Sensors (Basel) ; 24(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38610416

RESUMEN

This article presents an analysis of current state-of-the-art sensors and how these sensors work with several mapping algorithms for UAV (Unmanned Aerial Vehicle) applications, focusing on low-altitude and high-speed scenarios. A new experimental construct is created using highly realistic environments made possible by integrating the AirSim simulator with Google 3D maps models using the Cesium Tiles plugin. Experiments are conducted in this high-realism simulated environment to evaluate the performance of three distinct mapping algorithms: (1) Direct Sparse Odometry (DSO), (2) Stereo DSO (SDSO), and (3) DSO Lite (DSOL). Experimental results evaluate algorithms based on their measured geometric accuracy and computational speed. The results provide valuable insights into the strengths and limitations of each algorithm. Findings quantify compromises in UAV algorithm selection, allowing researchers to find the mapping solution best suited to their application, which often requires a compromise between computational performance and the density and accuracy of geometric map estimates. Results indicate that for UAVs with restrictive computing resources, DSOL is the best option. For systems with payload capacity and modest compute resources, SDSO is the best option. If only one camera is available, DSO is the option to choose for applications that require dense mapping results.

9.
Molecules ; 29(4)2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38398631

RESUMEN

Aqueous zinc ion batteries (AZIBs) have emerged as a promising battery technology due to their excellent safety, high capacity, low cost, and eco-friendliness. However, the cycle life of AZIBs is limited by severe side reactions and zinc dendrite growth on the zinc electrode surface, hindering large-scale application. Here, an electrolyte optimization strategy utilizing the simplest dipeptide glycylglycine (Gly-Gly) additive is first proposed. Theoretical calculations and spectral analysis revealed that, due to the strong interaction between the amino group and Zn atoms, Gly-Gly preferentially adsorbs on zinc's surface, constructing a stable and adaptive interfacial layer that inhibits zinc side reactions and dendrite growth. Furthermore, Gly-Gly can regulate zinc ion solvation, leading to a deposition mode shift from dendritic to lamellar and limiting two-dimensional dendrite diffusion. The symmetric cell with the addition of a 20 g/L Gly-Gly additive exhibits a cycle life of up to 1100 h. Under a high current density of 10 mA cm-2, a cycle life of 750 cycles further demonstrates the reliable adaptability of the interfacial layer. This work highlights the potential of Gly-Gly as a promising solution for improving the performance of AZIBs.

10.
Angew Chem Int Ed Engl ; : e202412245, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39226232

RESUMEN

Single atom catalysts (SACs) are promising non-precious catalysts for oxygen reduction reaction (ORR). Unfortunately, the ORR SACs usually suffer from unsatisfactory activity and in particular poor stability. Herein, we report atomically dispersed manganese (Mn) embedded on nitrogen and sulfur co-doped graphene as an efficient and robust electrocatalyst for ORR in alkaline electrolyte, realizing a half-wave potential (E1/2) of 0.883 V vs. reversible hydrogen electrode (RHE) with negligible activity degradation after 40,000 cyclic voltammetry (CV) cycles in 0.1 M KOH. Introducing sulfur (S) to form Mn-S coordination changes the spin state of single Mn atom from high-spin to low-spin, which effectively optimizes the oxygen intermediates adsorption over the single Mn atomic sites and thus greatly improves the ORR activity.

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