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BACKGROUND: Acute liver failure is one of the most intractable clinical problems. The use of bioartificial livers may solve donor shortage problems. Human umbilical cord mesenchymal stem cells (hUCMSCs) are an excellent seed cell choice for artificial livers because they change their characteristics to resemble hepatocyte-like cells (HLCs) following artificial liver transplantation. OBJECTIVE: This study aimed to determine whether the immunological characteristics of hUCMSCs are changed after being transformed into hepatocyte-like cells. METHODS: HUCMSCs were isolated by the adherent method. The following hUCMSC surface markers were detected using flow cytometry: CD45, CD90, CD105, CD34, and octamer-binding transcription factor 4 (OCT-4). Functional detection of adipogenic differentiation was performed. The hUCMSCs were cultured in complete medium (control group) or induction medium (induction group), and flow cytometry was used to detect cell surface markers. Peritoneal lavage fluid was collected after intraperitoneal injection of 1 × 106 cells/mouse over 40 minutes. The leukocyte count, labeled CD45, CD3, CD4 and CD8 antibodies, and flow detection of T lymphocyte subsets were determined using the peritoneal lavage fluid. RESULTS: Using phenotypic and functional identification, hUCMSCs were successfully isolated using a two-step induction method. The surface markers of the hUCMSCs cells changed after HLC induction. In vivo immune results showed that hUCMSCs and HLsC induced leukocyte production. CONCLUSION: Hepatic induction of hUCMSCs changes their cell surface markers. Both HLCs and hUCMSCs cause leukocytosis in vivo, but the immune response induced by HLCs is slightly stronger.

Cations with suitable sizes to occupy an interstitial site of perovskite crystals have been widely used to inhibit ion migration and promote the performance and stability of perovskite optoelectronics. However, such interstitial doping inevitably leads to lattice microstrain that impairs the long-range ordering and stability of the crystals, causing a sacrificial trade-off. Here, we unravel the evident influence of the valence states of the interstitial cations on their efficacy to suppress the ion migration. Incorporation of a trivalent neodymium cation (Nd3+) effectively mitigates the ion migration in the perovskite lattice with a reduced dosage (0.08%) compared to a widely used monovalent cation dopant (Na+, 0.45%). The photovoltaic performances and operational stability of the prototypical perovskite solar cells are enhanced with a trace amount of Nd3+ doping while minimizing the sacrificial trade-off.

Nowadays, in the context of the Internet of things and artificial intelligence, nationalization is an advanced school running concept. In China, some colleges have carried out an international school running mode and achieved certain results which provides theoretical support for the international operation of relevant university education, and also provides reference for the comprehensive benefit evaluation of other similar international university education. As an advanced school running concept, it has attracted the attention of many universities at home and abroad. Promoting the internationalization of universities is the general trend and a need of the development of higher education. Although some universities have started the practice of internationalization, there are differences and misunderstandings in the theory and practice of the internationalization of university education in China. There are many reasons for the differences, including the basic level of development, the level of theoretical understanding, the level of regional environmental background, and the level of specific operation and implementation. However, one of the important reasons is the lack of quantitative evaluation of the comprehensive benefits of the nationalization of university education. This study attempts to start from the reality of each university, adopt a systematic and scientific comprehensive benefit evaluation index system of university international operation, study the applicable and effective comprehensive benefit evaluation methods of university education international operation under the background of the Internet of things, and put forward suggestions and improvement measures for university education international operation, so as to provide theoretical support for China’s university education international operation. It provides reference and reference for the comprehensive benefit evaluation of international running of university education similar to other sample units.

Designing polymeric photocatalysts at the molecular level to modulate the photogenerated charge behavior is a promising and challenging strategy for efficient hydrogen peroxide (H2O2) photosynthesis. Here, we introduce electron-deficient 1,4-dihydroxyanthraquinone (DHAQ) into the framework of resorcinol-formaldehyde (RF) resin, which modulates the donor/acceptor ratio from the perspective of molecular design for promoting the charge separation. Interestingly, H2O2 can be produced via oxygen reduction and water oxidation pathways, verified by isotopic labeling and in situ characterization techniques. Density functional theory (DFT) calculations elucidate that DHAQ can reduce the energy barrier for H2O2 production. RF-DHAQ exhibits excellent overall photosynthesis of H2O2 with a solar-to-chemical conversion (SCC) efficiency exceeding 1.2%. This work opens a new avenue to design polymeric photocatalysts at the molecular level for high-efficiency artificial photosynthesis.

Semi-transparent organic photovoltaics (OPVs) are an emerging solar-energy-harvesting technology with promising applications, such as rooftop energy supplies for environmentally friendly greenhouses. However, the poor operational stability of OPVs poses challenges to their feasibility as incessantly serving facilities. Here we report a reductive interlayer structure for semi-transparent OPVs that improves the operational stability of OPVs under continuous solar radiation. The interlayer effectively suppresses the generation of radicals from the electron transport layer under sunlight and prevents the structural decomposition of the organic photoactive layer during operation. The defects that serve as the charge carrier recombination sites are nullified by the electron-donating functional groups of the reduced molecules, which improves photovoltaic performance. The semi-transparent OPVs demonstrate a power conversion efficiency of 13.5% and an average visible transmittance of 21.5%, with remarkable operational stability (84.8% retention after 1,008 h) under continuous illumination. Greenhouse results show that the semi-transparent OPV roof benefits the survival rate and growth of the crops, indicating the importance of our approach in addressing food and energy challenges.

A back-excitation transient reflection spectroscopy was developed to visualize longitudinal carrier transport in perovskite films, showing that the longitudinal diffusion coefficient decreases sharply with increasing thickness-to-grain-size ratio.

Precise control of the growth of 2D perovskites on 3D perovskites to form “trans-grain boundaries” 2D/3D structure for the preparation of flexible perovskite solar cells with a certified PCE up to 22.1% and excellent mechanical stability.

Coexistence of nonvolatile unipolar and volatile threshold resistive switching is observed in the Pt/LaMnO3 (LMO)/Pt heterostructures. The nonvolatile unipolar memory is achieved by applying a negative bias, while the volatile threshold resistive switching is obtained under a positive bias. Additionally, the pristine low resistance state (LRS) could be switched to high resistance state (HRS) by the positive voltage sweeping, which is attributed to the conduction mechanism of Schottky emission. Subsequently, the insulator-to-metal transition in the LMO film due to formation of ferromagnetic metallic phase domain contributes to the volatile threshold resistive switching. However, the nonvolatile unipolar switching under the negative bias is ascribed to the formation/rupture of oxygen-vacancy conducting filaments. The simultaneously controllable transition between nonvolatile and volatile resistance switching by the polarity of the applied voltage exhibits great significance in the applications of in-memory computing technology.

With large specific capacity, wide voltage window, and high energy density, Li-rich layered oxides have been considered as a promising cathode candidate for advanced lithium-ion batteries (LIBs). However, their commercial application is challenging due to severe capacity degradation and voltage fading caused by irreversible oxygen evolution and phase transition upon repeated cycling. This work proposes an effective strategy to improve the long-term electrochemical performances of Li

Summary Although great progress is being made toward improving the power conversion efficiency (PCE) and the operational stability of perovskite solar cells (PSCs), little attention is being paid to their mechanical reliability, which is particularly important for flexible PSCs (f-PCSs). Here, we have grown low-dimensional (LD) metal-halide perovskite (MHP) thin capping layer over the 3D MHP light-absorber thin film in f-PSCs in situ to improve their mechanical reliability. This resulted in f-PSCs with unprecedented, simultaneous improvements in PCE (21.0%), operational stability (T90, retention of 90% of the initial PCE, >800 h), and bending durability (T80 = 20,000 tension-only bending cycles). These synergistic virtuous effects are attributed to the LD MHP capping layer enhancing photocarriers extraction, providing protection against the environment, and “sealing” surface flaws on the 3D MHP thin film. The latter reduces the propensity for cracking in bending, which results in improved environmental stability and bending durability.

Tedious trial-and-error procedures are commonly practiced for surface modification of the perovskite solar cell (PSC) active layers. A guideline to rationally choose the passivating functional groups of the polymeric structure that is eminently effective in passivating the charged defects and elongating the device lifetime is hence in urgent demand. Herein, three prototypical polymers, poly(vinyl acetate) (PVA), polyethylene glycol (PEG), and poly(9-vinylcarbazole) (PVK), are selected to investigate the structural effect of the polymeric modification agents on the PSCs. We found that PVA possesses the Lewis base functional group with the minimized steric hindrance and the strongest electron-donating ability, enabling the most effective defect passivation on the perovskite film surface and the most enhanced carrier diffusion capacity. It demonstrates a power conversion efficiency (PCE) of 23.20% and noticeably enhanced operational stability. Our work provides important insights toward the selection of polymeric modification agents for high-performance and long-term stable PSCs.

All-inorganic perovskite materials have emerged as highly promising materials for solar cells and photoelectronic applications. However, the poor stability of perovskites in ambient conditions significantly hampers their practical applications. In this work, we report a three-step synthesis of size tunable CsPbX3 (X = Br, Cl, or I) quantum dots (QDs) embedded in zeolite-Y (CsPbX3-Y), which involves efficient chemical transformation of non-luminescent Cs4PbX6 to highly luminescent CsPbX3 by stripping CsX through an interfacial reaction with water. We show that the size and the emission of CsPbX3 in CsPbX3-Y can be tuned by the amount of water added as well as the halide composition. More importantly, the as-prepared CsPbX3-Y show significantly enhanced stability against moisture upon protection by zeolite-Y. This work not only reports a new pathway for the preparation of highly luminescent CsPbX3 but also provided new insights into the chemical transformation behavior and stabilization mechanism of these emerging perovskites.

The realization of highly efficient neuromorphic computing necessitates the development of fast artificial synaptic devices. Mott insulator artificial synapses, in particular, provide tremendous potential for ultrafast neuromorphic devices. In this work, based on Pt/LaMnO3/Pt heterostructures, a variety of synaptic plasticity has been realized, including paired-pulse facilitation/depression, spike rate-dependent plasticity (SRDP) and four types of spike time-dependent plasticity. Furthermore, Bienenstock–Cooper–Munro learning rules with a sliding frequency threshold have been found from SRDP. These findings make a significant contribution to brain-like neuromorphic computing.

Understanding the photoinduced carrier dynamics in Cs2AgBiBr6 double perovskites is essential for their application in optoelectronic devices. Herein, we report an investigation on the temperature-...

Currently, three-dimensional (3D) organic–inorganic hybrid metallic halide perovskites are emerging as optoelectronic materials, but they demonstrate poor stability against heat and moisture and are vulnerable to oxidation and photodegradation upon exposure to ultraviolet (UV) light. Herein, for the first time, 1,6-diaminohexane ammonium (HDAD+) is demonstrated to be a unique cation spacer to prepare a two-dimensional Dion–Jacobson phase (DJP) perovskite that is ultimately used to construct a 2D/3D stacking structure. Compared to 3D perovskites and Ruddlesden–Popper phase (RPP)-2D perovskites, the DJP-2D perovskite demonstrates superior UV stability and can efficiently protect the 3D layer underneath from being damaged by the UV light. Moreover, the DJP-2D perovskite can also act as an interfacial layer to passivate the defects located on top of the 3D perovskite, resulting in a notably increased photoluminescence lifetime and suppression of interfacial charge recombination. As a result, the power conversion efficiency (PCE) is enhanced from 19.22% (3D) to 20.31% (2D/3D) and is accompanied by improved moisture and thermal stabilities.

Manganese(II)-doped perovskite nanocrystals (NCs), because of their unique dual-color (from host excitons and Mn-dopants) emission property, are promising materials for various optical applications...

Exosomes are becoming an important mediator of the interaction between tumor cells and the microenvironment. Ferroptosis is a newly discovered type of cell death. However, its role in the progression of liver cancer is largely unknown. The aim of the presents study was to analyze the mechanism by which hepatitis B virus (HBV)-positive liver cancer secretes exosomes to mediate the iron death of M1 macrophages, thereby promoting the development of liver cancer.Liver cancer tissues and peripheral blood with positive and negative clinical HBV infection were collected, and M-type macrophages, miR-142-3p, and recombinant solute carrier family 3, member 2 (The expression of miR-142-3p significantly increased in the exosomes extracted from the peripheral blood of patients with HBV-positive liver cancer. Genes related to intracellular iron metabolism and homeostasis, such as ferritin heavy chain 1 (FTH1), transferrin receptor 1 (TfR1), recombinant glutathione peroxidase 4 (GPX4), and activating transcription factor 4 (ATF4), had abnormal expression levels in M1 macrophages. HBV-positive HCC exosomes treated with M1-type macrophages had a weakened inhibitory effect on the invasion of HCC cells, but ferroptosis inhibitors could reverse the effect of HBV-positive HCC exosomes treated M1-type macrophages on HCC cells. Knockdown of the expression of miR-142-3p can also weaken the invasive ability of liver cancer cells.The results of the present study confirmed that HBV-positive liver cancer cell exosomal miR-142-3p can promote the progression of liver cancer by inducing iron death of M1-type macrophages.

Low‐dimensional hybrid metal halides are emerging as a highly promising class of single‐component white‐emitting materials for their unique broadband emission from self‐trapped excitons (STEs). Despite substantial progress in the development of these metal halides, many challenges remain to be addressed to obtain a better fundamental understanding of the structure–property relationship and realize the full potentials of this class of materials. Here, via pressure regulation, a near 100% photoluminescence quantum yield (PLQY) of broadband emission is achieved in a corrugated 1D hybrid metal halide C5N2H16Pb2Br6, which possesses a highly distorted structure with an initial PLQY of 10%. Compression reduces the overlap between STE states and ground state, leading to a suppressed phonon‐assisted non‐radiative decay. The PL evolution is systematically demonstrated to be controlled by the pressure‐regulated exciton–phonon coupling which can be quantified using Huang–Rhys factor S. Detailed studies of the S‐PLQY relation for a series of 1D hybrid metal halides (C5N2H16Pb2Br6, C4N2H14PbBr4, C6N2H16PbBr4, and (C6N2H16)3Pb2Br10) reveal a quantitative structure–property relationship that regulating S factor toward 28 leads to the maximum emission., This work demonstrates a quantitative relationship between photoluminescence quantum yield (PLQY) and exciton–phonon coupling in a series of 1D hybrid metal halides. Using pressure to regulate the exciton–phonon interaction, a near 100% PLQY of broadband emission from self‐trapped excitons is achieved in a corrugated 1D compound C5N2H16Pb2Br6 whose initial PLQY is 10%.

Na3V2(PO4)3 (NVP) is a promising cathode for high-energy density sodium-ion batteries, whereas its electrochemical performance is also degraded by its intrinsically inferior electronic conductivity and interfacial side reactions. Herein, Li+, Al3+, and Ti4+ ions were incorporated into the near-surface, and NVP particles were encapsulated by a solid Na+ superionic conductor electrolyte Li1.4Al0.4Ti1.6(PO4)3 (LATP) and carbon (C). Typically, the 0.2 wt. % LATP/C-modified NVP electrode delivers a high initial discharge capacity of 91.22 mA h g−1 and a remarkable rate performance of 56.5 mA h g−1 (20 C). Intensive explorations manifest that the significant improvement in the electrochemical performance of NVP/C could be attributed to the synergistic effects of Li+, Al3+, and Ti4+ doping and the characteristic NVP/LATP/C sandwich coating structure. The modification strategy established in this work synchronously enhanced the electronic conductivity and structural stability of NVP, and this study also provides insight into well-designed electrode microstructures in high-performance batteries.

The growth behavior and electrical transport properties of ZnO films was found to be strongly dependent on the deionized water soaking treatment of 0.7 wt% (111) SrTiO3:Nb substrates. Comparing the ZnO films on soaked SrTiO3:Nb substrates with those on unsoaked ones, the out-of-plane orientation of ZnO films are both along the c-axis, while there is an in-plane rotation of ZnO thin films. According to the variable frequency capacitance–voltage measurements, a much higher interface state density is found in the ZnO/soaked-SrTiO3:Nb heterojunction than that in the ZnO/unsoaked-SrTiO3:Nb heterojunction. Moreover, a rectification and bipolar resistive switching effect were observed in the ZnO/unsoaked-SrTiO3:Nb and ZnO/soaked-SrTiO3:Nb heterojunctions, respectively. The transition from rectification to a bipolar resistive switching effect can be ascribed to an increase of oxygen vacancies, the migration of which plays an important part in the resistive switching.

Understanding the photoinduced carrier dynamics in Cs

The toxic kernel cake of Jatropha curcas (KCakeJ) is an emerging health and environmental concern. Although phorbol esters are widely recognized as the major toxin of KCakeJ, convincing evidence is absent. Here, we show that rather than phorbol esters an isomeric mixture of 11-hydroxy-9E-octadecenoic acid, 12-hydroxy-10E-octadecenoic acid and 12-hydroxy-10Z-octadecenoic acid (hydroxy-octadecenoic acids, molecular formula C18H34O3) is the major toxic component. The toxicities of hydroxy-octadecenoic acids on experimental animals, e.g. acute lethality, causing inflammation, pulmonary hemorrhage and thrombi, allergies, diarrhea and abortion, are consistent with those on human/animals caused by Jatropha seed and/or KCakeJ. The hydroxyl group and the double bond are essential for hydroxy-octadecenoic acids’ toxicity. The main pathway of the toxicity mechanism includes down-regulating UCP3 gene expression, promoting ROS production, thus activating CD62P expression (platelet activation) and mast cell degranulation. The identification of the major toxin of KCakeJ lays a foundation for establishing an environmentally friendly Jatropha biofuel industry.

Coexistence of nonvolatile unipolar memory and volatile threshold resistive switching was observed in Pt/LaMnO 3 /Pt system. Specifically, nonvolatile unipolar memory was achieved by applying a negative bias, while volatile threshold resistive switching was obtained at a positive bias. The formation/rupture of conducting filaments and insulator-metal transition are supposed to induce nonvolatile unipolar memory and volatile threshold resistive switching, respectively. The convenient transition between nonvolatile and volatile switching by polarity is very useful for applications in in-memory computing technology.

The growth behavior and electrical transport properties of ZnO films was found to be strongly dependent on the deionized water soaking treatment of 0.7 wt% (111) SrTiO

NiO films grown on Pt and Nb:SrTiO3 (NSTO) substrates display filament-type and interface-type resistance switching (RS), respectively. The resistance retention studies show that these two different RSs also lead to distinct resistance evolutions. For Pt/NiO/Pt, both high and low resistance states have good retention property, demonstrating that the conducting filament is stable once it is formed. However, for Pt/NiO/NSTO/In, all resistance states show time-relaxation, and the relaxation trend depends on the polarity of the write bias. The resistive relaxation and nonvolatile features are attributed to the charge migration and electron trapping scenario, respectively.

The continuous phase transformation from the layered structure to the spinel-like phase seriously degrades the electrochemical properties of Li-rich layered oxides in Lithium-ion batteries. Herein, heterostructured Li-rich cathode materials Li[Li 0.2 Ni 0.17 Co 0.07 Mn 0.56 ]O 2 in conjunction with different contents of Zr-containing phosphate (ZCP) coating layers were prepared. The structural and electrochemical characterizations reveal that the ZCP surface layer, which not only prevents electrolyte from eroding the Li-rich core and thus suppressing the fast growth of solid electrolyte interface film and charge transfer resistance on the surface of oxide particles, but also enhances the structural and thermal stabilities of the electrode. As a result, the 3 wt .% coated sample delivers an initial discharge capacity of 216 mAh g ⿿1 with a coulombic efficiency of 80%, compared to 202 mAh g ⿿1 and 71%, respectively, for the bare sample. Particularly, the coated sample demonstrates excellent cycling stability with a capacity retention of 91% within 100 cycles, and higher thermal stability.

Bi2MoO6/BiPO4 composites were successfully synthesized via a simple one-pot hydrothermal method. The samples were characterized by X-ray diffraction, field emission scanning electron microscope, transmission electron microscope and UV–Vis diffuse reflectance spectroscopy. The resulting Bi2MoO6/BiPO4 composites exhibit excellent photocatalytic activity and stability to methylene blue degradation under visible light (λ > 420 nm). The Mo:P = 3:4 sample shows the highest photocatalytic activity at different molar ratios. Different pH values have a considerable effect on the composites. When the pH value is 9, the sample shows the highest photocatalytic activity. The photocatalytic mechanism of Bi2MoO6/BiPO4 composites is mainly due to the higher separation efficiency of electron–hole pairs. A possible pathway of degradation of MB was proposed in this study. The effect of pH on the Bi2MoO6/BiPO4 composites is discussed.

The films of photocatalysts have been widely used in decomposition in organic pollutants. In this study, ZnWO 4 and g-C 3 N 4 /ZnWO 4 photocatalysts were made into films. The samples were evidently investigated by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), UV–vis diffuse reflectance spectroscopy (DRS), field emission on scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray photo-electron spectroscopy (XPS), thermal gravimetric analysis (TGA), Brunauer–Emmett–Teller (BET) and electrochemical experiments. After modified by g-C 3 N 4 , the g-C 3 N 4 /ZnWO 4 films presented a significantly enhanced photocatalytic performance in degrading phenol under UV irradiation (about 2 times than pure ZnWO 4 ). In conclusion, it was g-C 3 N 4 increasing the separation efficiency of photogenerated electron–hole pairs that contribute to the enhancement of photocatalytic performances. This work is of great value for preparation of photocatalysts films.

Temperature- and pulse amplitude/width dependent current-voltage characteristics were performed to study the variance of negative differential resistance (NDR) features accompanying bipolar resistive switching. Interestingly, the absolute value of the NDR peak intensity is enhanced at first and then weakened, while the NDR peak position gradually shifts toward the lower absolute bias value with an increase in temperature from 140 to 300 K, and shifts toward the larger absolute bias value with an increase in temperature from 300 to 400 K. Furthermore, the NDR peak is absent after applying a small and narrow positive pulse, while it gradually increases with increasing the applied pulse amplitude or width. These temperature- and pulse-dependent NDR behaviors can be fully understood based on a model of generation and drift of ionized oxygen vacancies coupled with trapping/detrapping electrons. The clarification of the mechanism will pave the way for practical applications.

A g-C3N4/bismuth oxychloride (BiOCl) heterojunction was prepared by ultrasonic method. The microstructure, morphology, properties, and photocatalytic activity of the heterojunction were characterized using X-ray diffraction, UV–Vis diffuse reflection spectroscopy, field emission scanning electron microscopy, Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy and electro-chemical experiments. After hybridized with g-C3N4, the absorption edge of g-C3N4/BiOCl showed a red shift that reached 440 nm, with a band gap (E g) calculated to be 2.82 eV. Under visible-light irradiation, the hybrid photocatalyst also showed activity for methylene-blue photodegradation that was approximately 6.3 times higher than the activity of pure BiOCl. The mechanism of photocatalytic activity enhancement involved increased separation of electrons and holes between g-C3N4 and BiOCl. This work significantly contributed to the improvement in photocatalytic activity of BiOCl.