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Converting biomass to produce renewable chemicals is one of the significant ways to realize the development of green chemistry and sustainable chemical industry. As the main component of lignocellulosic biomass, lignin is the most abundant natural polyphenol. Its unique phenolic properties and high carbon content make it potentially exploited. Biomass lignin depolymerization can be divided into thermochemical, chemical catalysis, electrocatalysis, and biological depolymerization methods. In this review, the catalytic reaction systems involved in different methods of lignin depolymerization were extensively described from various aspects, and the degradation products and reaction mechanisms were discussed and analyzed. The effects of novel green-deep eutectic solvents on biomass lignin depolymerization were reviewed in particular. Each method of biomass lignin depolymerization has its own advantages and disadvantages. The different sources of biomass lignin should be selected objectively according to its compositional structure, so as to achieve efficient biomass lignin depolymerization. In addition, the challenges and future development prospects of biomass lignin depolymerization were also discussed.

We report a pulsed-voltage method using a pseudocapacitive electrode to improve the efficiency of the electrochemical reaction for aqueous Cr(vi) detoxification.

BackgroundGlycogen synthase kinase 3β (GSK3β) was originally discovered to regulate glycogen synthesis and show a relationship to tumors. However, the biological functions of GSK3β in tumor-associated macrophages (TAMs) in cancers including hepatocellular carcinoma (HCC) remain unclear.MethodsThe enrichment of GSK3β in tumor tissues was assessed by Gene Expression Omnibus (GEO) database. The in vitro and in vivo assays assisted in evaluating how GSK3β in TAMs affected HCC in terms of proliferation, invasion and migration. Immunofluorescence was used to assess GSK3β expression in TAMs in the anti-PD1 therapy non-responsive HCC group and the responsive group. Western blot and coimmunoprecipitation were performed to demonstrate the interaction between GSK3β and PD-L1. We carried out in vivo experiments in a C57BL/6 mouse model of HCC established through subcutaneous injection.ResultsGEO single-cell RNA sequencing data suggested that GSK3β was highly enriched in TAMs of HCC. According to in vitro and in vivo experiments, reducing GSK3β in TAMs inhibits the cancer cell proliferation, invasion, and migration. The immunofluorescence and immunohistochemistry results confirmed that the GSK3β is significantly upregulated in TAMs of the anti-PD1 therapy non-responsive group in comparison with the responsive group. In vitro and in vivo experiments confirmed that reduced GSK3β in TAMs are capable of enhancing the sensitivity of anti-PD1 immunotherapy for HCC by decreasing PD-L1 ubiquitination. Mass spectrometry results suggested that high expression of CD14+GSK3β+in the peripheral blood mononuclear cell (PBMC) can predict non-responsive to anti-PD1 treatment. Moreover, escitalopram is confirmed to act as GSK3β inhibitor that can increase the sensitivity of anti-PD1 immunotherapy for HCC.ConclusionsThis study revealed that macrophage GSK3β deficiency can inhibit the development of HCC by inhibiting the M2 phenotype and enhance the sensitivity of anti-PD1 immunotherapy for HCC by decreasing PD-L1 ubiquitination. The expression of CD14+GSK3β+in PBMC can noninvasively predict anti-PD1 sensitivity in HCC patients, which provides novel strategies to predict anti-PD1 sensitivity, increase anti-PD1 therapeutic effect, and bring new hope for HCC patients.

Liver transplantation (LT) is the most effective treatment for various end-stage liver diseases. However, the cellular complexity and intercellular crosstalk of the transplanted liver have constrained analyses of graft reconstruction after LT.We established an immune-tolerated orthotopic LT mouse model to understand the physiological process of graft recovery and intercellular crosstalk. We employed single-cell RNA sequencing and cytometry by time-of-flight to comprehensively reveal the cellular landscape.We identified an acute and stable phase during perioperative graft recovery. Using single-cell technology, we made detailed annotations of the cellular landscape of the transplanted liver and determined dynamic modifications of these cells during LT. We found that 96% of graft-derived immune cells were replaced by recipient-derived cells from the preoperative to the stable phase. However, CD206+MerTK+ macrophages and CD49a+CD49b- natural killer cells were composed of both graft and recipient sources even in the stable phase. Intriguingly, the transcriptional profiles of these populations exhibited tissue-resident characteristics, suggesting that recipient-derived macrophages and natural killer cells have the potential to differentiate into 'tissue-resident cells' after LT. Furthermore, we described the transcriptional characteristics of these populations and implicated their role in regulating the metabolic and immune remodeling of the transplanted liver.In summary, this study delineated a cell atlas (type-proportion-source-time) of the transplanted liver and shed light on the physiological process of graft reconstruction and graft-recipient crosstalk.

A low-cost and green biorefinery will increase the economy and revenue from lignocellulosic biomass. This study demonstrated the effect of two-pot sequential pretreatment, comprising of ultrasound ethanol (USEL) synergized ternary deep eutectic solvent (TDES, choline chloride: glycerol: FeCl3·6H2O), with the aim to investigate the effects of USEL, TDES, and USEL + TDES pretreatments on enhancing delignification of sugarcane bagasse (SCB). The results showed that under the optimum TDES pretreatment conditions (FeCl3·6H2O, 120 °C, 3 h), the cellulose content and lignin removal rate (LRR) of SCB reached 47.67 and 82.71%, respectively. Under the optimum synergy conditions (USEL conditions: 100% ethanol, 20 + 28 + 40 kHz, 240 W, 60 min; TDES conditions: FeCl3·6H2O, 120 °C, 3 h), the cellulose content and LRR of SCB reached 66.17 and 86.39%, respectively. After enzymatic hydrolysis, the SCB pretreated with USEL + TDES shows a saccharification rate of 90.31%, which was substantially higher than that of the SCB pretreated with TDES alone (85.68%). X-ray diffraction, particle size, brunauer-emmet-teller, scanning electron microscopy, and optical microscopy analyses were conducted to confirm the efficiency of USEL + TDES on pretreating SCB. Meanwhile, 2D-HSQC NMR analysis revealed that regenerated lignin exhibited well-preserved structures (β-O-4, β-β linkages), making it suitable for depolymerization into monoaromatic compounds. Overall, this work demonstrated that biomass pretreatment with the USEL + TDES was promising for a low-cost biorefinery to efficiently fractionate lignocellulosic biomass into glucose and high-quality lignin with tailored chemical structures.

Here, we introduce an innovative "poison arrowhead" approach for disinfection based on a nanosheet bacterial inactivation system that acts synergistically to achieve sterilization rates of >99.99 % (Escherichia coli) over an ultrashort time period (≈0.5 min). The two-dimensional MoS2 "arrowhead" configuration has a sharp edge structure that enables the vigorous extraction of lipids from cell membranes and subsequent membrane disruptions. In the presence of permonosulfate, a strong oxidant, sulfur vacancies containing MoS2 activate the stable molecules, which in turn produce reactive oxygen species (ROS) from edge sites to basal areas. This process not only scavenges some portion of the phospholipids to allow for MoS2 surface refreshment but also directly attacks proteins thereby inflicting further damage to injured cells and amplifying the cell-membrane-destructive stresses toward pathogenic microorganisms. With small amounts of the new material, we successfully disinfected natural water (≈99.93 % inactivation in terms of total bacteria) within 30 s.

Hot electron shows the merits of activating reactants and reducing the activation energy barrier (Ea) of a reaction through electron donation. However, a comprehensive understanding on the intrinsic driving force of electron-donating effect is lacking, let alone the precise manipulation of electron donation processes. Herein, the essential and promotional role of hot electron energy on electron-donating effect was elucidated using molecular oxygen activation (MOA) as a model reaction. Through providing an available electron source to the conventional photo-thermal conversion system, the high energy carried by hot electrons was liberated and greatly enhanced the electron donation towards the LUMO (π*) orbit of O2. The energy was also transferred to O2 and elevated the potential energy surface (PES) of MOA, which was reflected by the enhanced formation of superoxide oxygen anions. As predicted, the Ea of MOA decreased by 45.3% and exhibited a substantial light dependence, demonstrating that MOA became energy-efficient due to improved exploitation and conversion of photon energies.

Hydroxyl radical (•OH) can hydroxylate or dehydrogenate organics without forming extra products and is thereby expediently applied in extensive domains. Although it can be efficiently produced through single-electron transfer from transition-metal-containing activators to hydrogen peroxide (H2O2), narrow applicable pH range, strict activator/H2O2 ratio requirement, and byproducts that are formed in the mixture with the background matrix necessitate the need for additional energy-intensive up/downstream treatments. Here, we show a green Fenton process in an electrochemical cell, where the electro-generated atomic H* on a Pd/graphite cathode enables the efficient conversion of H2O2 into •OH and subsequent degradation of organic pollutants (80% efficiency). Operando liquid time-of-fight secondary ion mass spectrometry verified that H2O2 activation takes place through a transition state of the Pd-H*-H2O2 adduct with a low reaction energy barrier of 0.92 eV, whereby the lone electron in atomic H* can readily cleave the peroxide bridge, with •OH and H2O as products (ΔGr = -1.344 eV). Using H+ or H2O as the resource, we demonstrate that the well-directed output of H* determines the pH-independent production of •OH for stable conversion of organic contaminants in wider pH ranges (3-12). The research pioneers a novel path for eliminating the restrictions that are historically challenging in the traditional Fenton process.

Purpose Circular RNAs (circRNAs) are a new class of RNA molecules whose function is largely unknown. There is a growing evidence that circRNAs play an important regulatory role in the progression of a variety of human cancers. However, the exact roles and the mechanisms of circRNAs in gastric cancer are not clear. In this study, we aimed to elucidate the mechanism of hsa_circ_0005556. Materials and methods Real-time quantitative polymerase chain reaction was used to detect the expression of hsa_circ_0005556, miR-4270, and matrix metalloproteinase-19 (MMP19) in gastric cancer tissues and cell lines. The expression of hsa_circ_0005556 in gastric cancer cells was silenced by lentivirus, and cell proliferation, invasion, migration, and tumorigenesis in nude mice were assessed to evaluate the function of hsa_circ_0005556 in gastric cancer. Results The expression of hsa_circ_0005556 in gastric cancer tissues and gastric cancer cell lines was higher compared to normal controls. In vitro, the downregulation of hsa_circ_0005556 significantly inhibited proliferation, migration, and invasion of gastric cancer cells. In vivo, the downregulation of hsa_circ_0005556 suppressed tumor growth in nude mice. Conclusions Our study shows that the hsa_circ_0005556/miR-4270/MMP19 axis is involved in proliferation, migration, and invasion of gastric cancer cells through the competing endogenous RNA (ceRNA) mechanism.

Electrocatalytic two-electron oxygen reduction reaction (2e− ORR) is a promising strategy to achieve hydrogen peroxide (H2O2) production, which can replace the anthraquinone method in industrial processes. Nitrogen-doped carbon materials are active and selective electrocatalysts for 2e− ORR; however, it remains challenging to develop N-doped carbons for practical H2O2 production and pinpoint the exact role of nitrogen functionalities. Here, we examine covalent organic framework-derived nitrogen-doped carbons with well-defined porous structure and tunable N species for electrocatalytic H2O2 production. Electrochemical studies show their highest ORR activity and H2O2 selectivity of up to 75% in alkaline electrolyte. Notably, chronoamperometric bulk electrolysis achieves an unprecedented carbon-catalyzed H2O2 yield rate of 1286.9 mmol gcatalyst−1 h−1 and a faradaic efficiency of 69.8% at pH 13. X-ray photoelectron spectroscopy analysis combined with control experiments reveals that graphitic N is responsible for H2O2 production from 2e− ORR on N-doped carbons. Our work provides insights into the rational development of heteroatom-doped carbon electrocatalysts for efficient H2O2 generation.

Revealing the dynamic processes at the electrode-solution interface is imperative for understanding electrochemical phenomena. Most techniques have been developed to sense the electrode surface changes at the nanoscale, but provide limited information on potential-induced interfacial ion redistribution at the mesoscale. Herein, we present an in operando visualization method utilizing a microfabricated electrochemical cell combined with a laser scanning confocal microscope to observe high-resolution and fast-response interfacial processes. We report potential-induced formation and transformation of the Nernst diffusion layer, demonstrating that pulsed voltage dynamically perturbs the interface and promotes ion diffusion. This provides an additional insight into developing a dynamic manipulation method to control the electrochemical process. Our novel visualization method can easily be applied to monitor different ionic behaviors in electrochemical reactions at the mesoscale.

Treatment of hepatitis C virus (HCV) infection with direct-acting antiviral agents (DAAs) in hemodialysis patients requires extensive consideration. At present, studies regarding DAAs for acute HCV infection in such patients are limited. The present study aims to evaluate the efficacy and safety of grazoprevir (GZR) plus elbasvir (EBR) treatment in acute hepatitis C (AHC) patients undergoing hemodialysis. Patients undergoing hemodialysis who had a nosocomial acute HCV infection were enrolled. All patients received GZR 100 mg/EBR 50 mg once daily for 12 weeks and were followed up for 12 weeks. Serum alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), and HCV RNA levels were monitored during treatment and follow-up periods. Sustained virologic response (SVR) at 12 weeks after treatment cessation and treatment emergent adverse events (AEs) were assessed. A total of 68 AHC patients were enrolled. All patients were infected with HCV genotype 1b and achieved SVR12. Decreasing ALT, AST, and TBIL were observed over time in the first four weeks and became steady thereafter. Forty-eight (70.59%) patients reported at least one AEs. The most common AEs were fatigue, headache, and nausea. Two AHC patients discontinued treatment due to serious but drug-unrelated AEs. In conclusion, GZR/EBR has a high efficacy and safety profile in hemodialysis-dependent patients with genotype 1b AHC. This article is protected by copyright. All rights reserved.

In this article, we propose a penalized local log-likelihood method to locally select the number of components in non parametric finite mixture of regression models via proportion shrinkage method....

Here, we develop an optical tweezers-based single-molecule manipulation assay to detect the formation of an R-loop complex in the Cas12a system and characterize its thermodynamic stability. We found that the formation of the R-loop complex induces a two-step unfolding of a DNA hairpin containing the target sequence, the non-target sequence binds loosely to Cas12a and can be easily released from the complex, and the Nuc domain of Cas12a plays key roles in target binding and R-loop formation.

Solar evaporation is regarded as a promising and sustainable technology to address global clean water crisis. Tremendous efforts have been made for the development of new materials and structures, but heat utilization efficiency and stable salt-rejection remain the major challenges. In this study, a novel sugarcane-derived anisotropic structure with heat–mass flux decoupling effects was invented, and it exhibited outstanding salt-rejection and high efficiency in solar desalination. Numerical simulations revealed that heat–mass flux decoupling was achieved by making the mass flux perpendicular to the heat flux. The horizontally distributed channels provided sufficient water flux towards evaporation surface while transporting the concentrated salt ions from the surface back to the bulk water driven by the concentration gradient. Moreover, temperature gradient-driven heat transfer was effectively suppressed owing to the discontinuous and deficient water flux in the vertical direction. This anisotropic structure showed high efficiency (>80%) and excellent salt-rejecting performance for a wide range of salinities (0–15 wt%) and different solar densities (0.8–3 sun). Furthermore, stable performance was observed during long-term evaporation experiments under harsh operating conditions.

Metal–organic frameworks (MOFs) have attracted increasing interest for adsorption applications due to their ultrahigh porosity and specific surface area. However, their adsorption performance in liquids, particularly for water treatment, is significantly limited by the poor accessibility of micropores inside the MOF matrix to most molecules and deficient active sites. Herein, we use a facile strategy, ligand selective thermolysis, to create oxygen vacancies and construct mesopores in water stable UiO-66. The obtained hierarchically porous UiO-66 (HP-UiO-66) has tunable oxygen vacancies and mesopores, and outperforms the state-of-the-art MOF based adsorbents reported so far in removing arsenic, achieving an ultrahigh adsorption capacity of 248.75 mg g−1 under neutral conditions. Extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) analysis and density functional theory (DFT) calculations reveal that arsenic is mainly captured by forming bidentate Zr–O–As bonds between arsenate and HP-UiO-66 via occupying coordinatively unsaturated zirconium atoms. This study offers a new strategy for designing ultrahigh performance MOF based adsorbents.

The purpose of this study was to efficiently convert the sugary food waste (SFW) to 5-hydroxymethylfurfural (5-HMF) by ultrasound-[Bmim]Cl pretreatment in ionic liquids (ILs)-ion exchange resin system. The effect of ultrasonic pretreatment on SFW and the effect of ultrasonic frequency, ILs, acid resin and catalyst load on SFW conversion were studied. The kinetic curve and the relationship between products and intermediates were studied. In addition, the structure of SFW was also studied by FT-IR and SEM. The results indicated ultrasound-[Bmim]Cl pretreatment can significantly promote the dissolution of cellulose in SFW, and the optimal ultrasonic frequency, solvent and catalyst were 20 + 40 + 60 kHz, [Bmim]Cl and D001-cc resin, respectively; under the best reaction conditions, the maximum 5-HMF yields from the orange and apple wastes were 42.15 and 44.66 mol%, respectively. The kinetic studies showed that the early stage of 100 and 120 °C was mainly the hydrolysis reaction, and late stage was mainly isomerization and dehydration reaction; the early stage of 140 and 160 °C was a rapid hydrolysis and dehydration reaction, and the late stage was mainly the rehydration reaction of 5-HMF. The relationship between the intermediate precursors and 5-HMF showed that the rates of formation and rehydration of 5-HMF increased with the increase in temperature, and the formation reaction was mainly concentrated in zone II. The FT-IR and SEM results of degradation products showed that cellulose in SFW was more easily hydrolyzed at high temperature and long time.

Degradation of chlorinated disinfection by-products using the electroreduction process has been considered as a promising approach for advanced water treatment, while the removal efficiency is restricted by a high barrier for dechlorination of intermediates only by reductive atomic hydrogen (H*) and excessive cost required for reducing atmosphere. In this paper, we predict that the dechlorination efficiency for trichloroacetic acid (TCA), a typical chlorinated disinfection by-product, can be accelerated via a synchronous reduction-oxidation process, where the dechlorination barrier can be lowered by the oxidation reactions toward the critical intermediates using hydroxyl radicals (·OH). Based on scientific findings, we constructed a synchronous reduction-oxidation platform using a Pd-loaded Cu/Cu2O/CuO array as the core component. According to the combined results of theoretical and experimental analyses, we found that the high dispersion of nano-sized Pd on a photocathode was beneficial for the production of a high concentration of H* at low overpotential, a perquisite for initiating the dechlorination reaction. Simultaneously, excess H* has the potential to convert O2 to H2O2 in ambient conditions (air condition), and H2O2 can be further activated by a Cu-containing substrate to ·OH for attacking the critical intermediates. In this system, ∼89.1% of TCA was completely dechlorinated and ∼26.8% mineralization was achieved in 60 min, which was in contrast to the value of ∼65.7% and mineralization efficiency of only ∼1.7% achieved through the reduction process (Ar condition).

Surface-adsorbed active species are intermediates with strong activities in heterogeneous catalytic reactions. Effective stabilization of these intermediates is crucial to improve the catalytic performance. Here, we demonstrated highly active bimetallic palladium-indium (Pd-In) nanoparticles (NPs) that can stabilize atomic H* on the surface and show efficient electrocatalytic reduction performance toward bromate. The optimal atomic ratio of Pd to In was investigated with the aim of efficient formation and strong stabilization of H*, thus facilitating the reduction and decontamination of carcinogenic bromate. Pd2In3 was the most active catalyst, with a high rate constant of 0.029 min-1, whereas the rate constant for monometallic Pd NPs was only 0.009 min-1. Density functional theory calculations suggest that Pd2In3 NPs decrease the work function and provide strong H* stabilization ability. By employing a flow-through electrode coated with Pd2In3 NPs to enhance the mass transport, the utilization of H* could be boosted and the reduction kinetics increased up to 7.5 times.

Utilization of photocatalytic reactions to trigger persistent large-scale reactions could be an alternative path for practical solar energy conversion to relieve environmental pressure nowadays. We took the view that the photoinduction of transition states was critical for improving the activity of catalytic reactions. On the basis of theoretical predictions, the reaction Gibbs free energy of permonosulfate (PMS) activation can be rapidly reduced by molybdenum with low valence. We therefore constructed a multiphasic molybdenum dichalcogenide (MoS2) heterostructure-based photosystem that enabled generation of Mo transition states by visible light excitation. According to combination results of electron paramagnetic resonance, photoelectrochemical analysis, and X-ray photoelectron spectroscopy, we confirmed that the optimized 2H/1T heterojunction permitted the transport of excited interfacial electrons from the semiconductive 2H phase to the metallic 1T phase, and synchronously partially reduced Mo(IV) to Mo(III) at the interface. This intensified the charge transfer between the MoS2 and PMS-containing solution, thereby efficiently splitting the PMS molecules into •OH and SO4•- radicals. In this system, a type of refractory herbicide, 2,4-dichlorophenoxyacetic acid (2,4-D), can be degraded within 60 min at a rate constant of 6.20 × 10-2 min-1 using multiphasic MoS2 with a 1T/2H ratio of 1:1.

A N2 fixation by the electrocatalytic nitrogen reduction reaction from humidified air is regarded to be a critical tool for producing NH3 and reducing the globally accelerating CO2 emissions. Notwithstanding great efforts to improve catalyst activity and selectivity, promoting catalyst accessibility to high N2 concentrations to ensure that active sites fulfill their function should be a promising design direction. Here, Au nanoparticles are firmly anchored through atomic O on the surface of two-dimensional Ti3C2 using an ultrasound reduction process. Akin to the conspicuous role of the web in the predatory process of spiders, N2 adsorption experiments primarily suggest that a Ti3C2 "web" is beneficial for extraction of N2 from air, and embedding high valence-state Au clusters in the Ti3C2 "web" strengthens the chemical bonding effect toward N2 molecules. The high energy of N2 adsorption on the interface between gold clusters and Ti3C2 is the driving force for weakening triple N≡N bonds, and thereby the activation energy barrier is lowered via effective stabilization of N2H* species and destabilizing NH2NH2* under an alternative pathway. With Au loading content of ∼0.94%, Au/Ti3C2 exhibits an outstanding average yield of 30.06 μg h-1 mg-1 for NH3 production, with a high Faraday efficiency of 18.34% at -0.2 V.

Lanthanum (La)-based materials have been recognized as promising adsorbents for aqueous phosphate removal. The incorporation of base metals into La (oxy)hydroxides represents an effective strategy to improve adsorption performance. Understanding how base metals affect phosphate adsorption is challenging but essential for the development of effective materials for phosphorus control. Herein, we demonstrated a high-performance LaFe (oxy)hydroxide and studied its mechanisms on phosphate adsorption. The P K edge X-ray absorption near edge structure (XANES) analysis showed that PO43- was preferentially bonded with La, and the lattice oxygen in LaFe (oxy)hydroxide was demonstrated to be the active site. The O K edge XANES suggested that Fe optimized the electron structure of La, and Fe/La metal orbital hybridization resulted in the shift of oxygen p character to unoccupied states, facilitating phosphate adsorption. Furthermore, surface analysis showed that the pore size and volume were increased due to the introduction of Fe, which enabled efficient utilization of the active sites and fast adsorption kinetics. The dual effects of Fe in LaFe (oxy)hydroxide greatly enhance the effectiveness of La and represent a new strategy for the development of future phosphorus-control materials.