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Anion exchange membrane water electrolysis (AEMWE) offers a sustainable path for hydrogen production with advantages such as high current density, dynamic responsiveness, and low-cost electrocatalysts. However, the development of efficient and durable oxygen evolution reaction (OER) electrocatalysts under operating conditions is crucial for achieving the AEMWE. This study systematically investigated Fe-Co-Ni ternary amorphous electrocatalysts for the OER in AEMWE through a comprehensive material library system comprising 21 composition series. The study aims to explore the relationship between composition, degree of crystallinity, and electrocatalytic activity using ternary contours and binary plots to derive optimal catalysts. The findings reveal that higher Co and lower Fe contents lead to increased structural disorder within the Fe-Co-Ni system, whereas an appropriate amount of Fe addition is necessary for OER activity. It is concluded that the amorphous structure of Fe-Co3-Ni possesses an optimal ternary composition and degree of crystallinity to facilitate the OER. Post-OER analyses reveal that the optimized ternary amorphous structure induces structural reconstruction into an OER-favorable OOH-rich surface. The Fe-Co3-Ni electrocatalysts exhibit outstanding performances in both half-cells and single-cells, with an overpotential of 256 mV at 10 mA cm- 2 and a current density of 2.0 A cm- 2 at 1.89 V, respectively.

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Aqueous Zn-ion batteries (AZIBs) are promising energy-storage devices owing to their exceptional safety, long cycle life, simple production, and high storage capacity. Manganese oxides are considered potential cathode materials for AZIBs, primarily because of their safety, low cost, simple synthesis, and high storage capacity. However, MnO2-based cathodes tend to deteriorate structurally during long-term cycling, which reduces their reversible capacity. In this study, an advanced α-MnO2@SnO2 nanocomposite via facile hydrothermal synthesis is developed. The synergistic effects of lattice disorder and increased electron conductivity in the α-MnO2@SnO2 nanocomposite mitigate structural degradation and enhance the overall electrochemical performance. The nanocomposite exhibits a high reversible capacity of 347 mAh g-1 at a current density of 100 mA g-1 after 50 cycles. Furthermore, it exhibits excellent rate performance and stable capacity even after 1000 cycles, maintaining a capacity of 78 mAh g-1 at a high current density of 5 A g-1. This excellent electrochemical performance is attributed to the reversible Zn intercalation in α-MnO2@SnO2 nanocomposites due to the increased structural stability and fast ion/electron exchange caused by the distortion of the tunnel structure, on the basis of various ex situ experiments, density functional theory calculations, and electrochemical characterizations.

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Inflammatory bowel disease (IBD) is a chronic disorder characterized by recurrent gastrointestinal inflammation, lacking a precise aetiology and definitive cure. The gut microbiome is vital in preventing and treating IBD due to its various physiological functions. In the interplay between the gut microbiome and human health, extracellular vesicles secreted by gut bacteria (BEVs) are key mediators. Herein, we explore the role of Roseburia intestinalis (R)-derived EVs (R-EVs) as potent anti-inflammatory mediators in treating dextran sulfate sodium-induced colitis. R was selected as an optimal BEV producer for IBD treatment through ANCOM analysis. R-EVs with a 76 nm diameter were isolated from R using a tangential flow filtration system. Orally administered R-EVs effectively accumulated in inflamed colonic tissues and increased the abundance of Bifidobacterium on microbial changes, inhibiting colonic inflammation and prompting intestinal recovery. Due to the presence of Ile-Pro-Ile in the vesicular structure, R-EVs reduced the DPP4 activity in inflamed colonic tissue and increased the active GLP-1, thereby downregulating the NFκB and STAT3 via the PI3K pathway. Our results shed light on the impact of BEVs on intestinal recovery and gut microbiome alteration in treating IBD.

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Water electrolyzers powered by renewable energy are emerging as clean and sustainable technology for producing hydrogen without carbon emissions. Specifically, anion exchange membrane (AEM) electrolyzers utilizing non-platinum group metal (non-PGM) catalysts have garnered attention as a cost-effective method for hydrogen production, especially when integrated with solar cells. Nonetheless, the progress of such integrated systems is hindered by inadequate water electrolysis efficiency, primarily caused by poor oxygen evolution reaction (OER) electrodes. To address this issue, a NiFeCo─OOH has developed as an OER electrocatalyst and successfully demonstrated its efficacy in an AEM electrolyzer, which is powered by renewable electricity and integrated with a silicon solar cell.

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Cannabidiol (CBD), a primary constituent in hemp and cannabis, exerts broad pharmacological effects against various diseases, including cancer. Additionally, cabozantinib, a potent multi-kinase inhibitor, has been approved for treating patients with advanced hepatocellular carcinoma (HCC). Recently, there has been an increase in research on combination therapy using cabozantinib to improve efficacy and safety when treating patients. Here, we investigated the effect of a combination treatment of cabozantinib and CBD on HCC cells. CBD treatment enhanced the sensitivity of HCC cells to cabozantinib-mediated anti-cancer activity by increasing cytotoxicity and apoptosis. Phospho-kinase array analysis demonstrated that the apoptotic effect of the combination treatment was mainly related to p53 phosphorylation regulated by endoplasmic reticulum (ER) stress when compared to other kinases. The inhibition of p53 expression and ER stress suppressed the apoptotic effect of the combination treatment, revealing no changes in the expression of Bax, Bcl-2, cleaved caspase-3, cleaved caspase-8, or cleaved caspase-9. Notably, the effect of the combination treatment was not associated with cannabinoid receptor 1 (CNR1) and the CNR2 signaling pathways. Our findings suggest that the combination therapy of cabozantinib and CBD provides therapeutic efficacy against HCC.

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Surface Pourbaix diagrams are critical to understanding the stability of nanomaterials in electrochemical environments. Their construction based on density functional theory is, however, prohibitively expensive for real-scale systems, such as several nanometer-size nanoparticles (NPs). Herein, with the aim of accelerating the accurate prediction of adsorption energies, we developed a bond-type embedded crystal graph convolutional neural network (BE-CGCNN) model in which four bonding types were treated differently. Owing to the enhanced accuracy of the bond-type embedding approach, we demonstrate the construction of reliable Pourbaix diagrams for very large-size NPs involving up to 6525 atoms (approximately 4.8 nm in diameter), which enables the exploration of electrochemical stability over various NP sizes and shapes. BE-CGCNN-based Pourbaix diagrams well reproduce the experimental observations with increasing NP size. This work suggests a method for accelerated Pourbaix diagram construction for real-scale and arbitrarily shaped NPs, which would significantly open up an avenue for electrochemical stability studies.

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Most studies related to hemp are focused on Cannabidiol (CBD) and Tetrahydrocannabinol (THC); however, up to 120 types of phytocannabinoids are present in hemp. Hemp leaves contain large amounts of Cannabidiolic acid (CBDA) and Tetrahydrocannabinolic acid (THCA), which are acidic variants of CBD and THC and account for the largest proportion of CBDA. In recent studies, CBDA exhibited anti-hyperalgesia and anti-inflammatory effects. THCA also showed anti-inflammatory and neuroprotective effects that may be beneficial for treating neurodegenerative diseases. CBDA and THCA can penetrate the blood-brain barrier (BBB) and affect the central nervous system. The purpose of this study was to determine whether CBDA and THCA ameliorate Alzheimer's disease (AD)-like features in vitro and in vivo. The effect of CBDA and THCA was evaluated in the Aß1-42-treated mouse model. We observed that Aß1-42-treated mice had more hippocampal Aß and p-tau levels, pathological markers of AD, and loss of cognitive function compared with PBS-treated mice. However, CBDA- and THCA-treated mice showed decreased hippocampal Aß and p-tau and superior cognitive function compared with Aß1-42-treated mice. In addition, CBDA and THCA lowered Aß and p-tau levels, alleviated calcium dyshomeostasis, and exhibited neuroprotective effects in primary neurons. Our results suggest that CBDA and THCA have anti-AD effects and mitigate memory loss and resilience to increased hippocampal Ca2+, Aß, and p-tau levels. Together, CBDA and THCA may be useful therapeutic agents for treating AD.

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A facile new synthetic method for the preparation of a Type-A 1-arylnaphthalene lactone skeleton was developed and used to synthesise justicidin B and several derivatives. Key synthesis steps included Hauser-Kraus annulation of a phthalide intermediate and Suzuki-Miyaura cross coupling between a triflated naphthalene lactone intermediate and various potassium organotrifluoroborates. With two exceptions, the derivatives showed significant inhibitory effect on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in mouse macrophages. Moreover, several compounds, including justicidin B, had marked cytotoxicity towards six human tumour cell lines.

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Faecalibacterium prausnitzii (F. prausnitzii) is one of the most abundant bacteria in the human intestine, with its anti-inflammatory effects establishing it as a major effector in human intestinal health. However, its extreme sensitivity to oxygen makes its cultivation and physiological study difficult. F. prausnitzii produces butyric acid, which is beneficial to human gut health. Butyric acid is a short-chain fatty acid (SCFA) produced by the fermentation of carbohydrates, such as dietary fibre in the large bowel. The genes encoding butyryl-CoA dehydrogenase (BCD) and butyryl-CoA:acetate CoA transferase (BUT) in F. prausnitzii were cloned and expressed in E. coli to determine the effect of butyric acid production on intestinal health using DSS-induced colitis model mice. The results from the E. coli Nissle 1917 strain, expressing BCD, BUT, or both, showed that BCD was essential, while BUT was dispensable for producing butyric acid. The effects of different carbon sources, such as glucose, N-acetylglucosamine (NAG), N-acetylgalactosamine (NAGA), and inulin, were compared with results showing that the optimal carbon sources for butyric acid production were NAG, a major component of mucin in the human intestine, and glucose. Furthermore, the anti-inflammatory effects of butyric acid production were tested by administering these strains to DSS-induced colitis model mice. The oral administration of the E. coli Nissle 1917 strain, carrying the expression vector for BCD and BUT (EcN-BCD-BUT), was found to prevent DSS-induced damage. Introduction of the BCD expression vector into E. coli Nissle 1917 led to increased butyric acid production, which improved the strain's health-beneficial effects.

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The alkaline environment in anion-exchange membrane fuel cells allows the use of Pt-free electrocatalysts, thus reducing the system cost. We performed a theoretical high-throughput study of various low-cost Ag-based oxygen reduction reaction anode electrocatalysts and assessed their catalytic performance using density functional theory. From the Materials Project database, a total of 106 binary Ag alloys were investigated by estimating their heat of formation, dissolution potential, and overpotential on low-index surfaces. We confirmed that EuAg5, BaAg5, and SrAg5 have higher catalytic activities and durabilities than pure Ag. By following the chemical trend of the results, we further proposed LaAg5 and PrAg5, which were not included in the database, as promising candidates. All candidates are in the space group P6/mmm and contain alkaline earth metal or lanthanide elements.

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BACKGROUND: Lung cancer has a high incidence worldwide, and most lung cancer-associated deaths are attributable to cancer metastasis. Although several medicinal properties of Panax ginseng Meyer have been reported, the effect of ginsenosides Rk1 and Rg5 on epithelial-mesenchymal transition (EMT) stimulated by transforming growth factor beta 1 (TGF- ß1) and self-renewal in A549 cells is relatively unknown. METHODS: We treated TGF-ß1 or alternatively Rk1 and Rg5 in A549 cells. We used western blot analysis, real-time polymerase chain reaction (qPCR), wound healing assay, Matrigel invasion assay, and anoikis assays to determine the effect of Rk1 and Rg5 on TGF-mediated EMT in lung cancer cell. In addition, we performed tumorsphere formation assays and real-time PCR to evaluate the stem-like properties. RESULTS: EMT is induced by TGF-ß1 in A549 cells causing the development of cancer stem-like features. Expression of E-cadherin, an epithelial marker, decreased and an increase in vimentin expression was noted. Cell mobility, invasiveness, and anoikis resistance were enhanced with TGF-ß1 treatment. In addition, the expression of stem cell markers, CD44, and CD133, was also increased. Treatment with Rk1 and Rg5 suppressed EMT by TGF-ß1 and the development of stemness in a dose-dependent manner. Additionally, Rk1 and Rg5 markedly suppressed TGF-ß1-induced metalloproteinase-2/9 (MMP2/9) activity, and activation of Smad2/3 and nuclear factor kappa B/extra-cellular signal regulated kinases (NF-kB/ERK) pathways in lung cancer cells. CONCLUSIONS: Rk1 and Rg5 regulate the EMT inducing TGF-ß1 by suppressing the Smad and NF-κB/ERK pathways (non-Smad pathway).

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The first total synthesis of pactalactam was accomplished using substrate-controlled stereoselective aziridination and regioselective aziridine ring-opening to construct three continuous amino groups on an octasubstituted cyclopentane core. The cyclopentane framework was obtained by ring-closing metathesis and aldol coupling using a l-threonine-derived oxazoline compound. Cyclic urea formation, m-acetylphenyl group introduction by Chan-Lam coupling, and primary alcohol-selective acylation yielded the reported pactalactam structure. The presence of pactalactam in the fermentation broth of pactamycin-producing bacteria was also confirmed.

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The association between adverse effects of PPI and gut microbiota in old age has yet to be elucidated. We assessed changes in the gut microbiota and butyrate levels following the long-term administration of PPIs to old rats and investigated their associations. F344 aged male rats were fed a PPI-supplemented diet for 50 weeks. The ileal microbiota was analysed by metagenomic sequencing of the 16S rRNA, while the butyrate concentration was measured by high-performance liquid chromatography. We observed a significant decrease in microbial diversity following PPI administration in the 2-year-old rats but not in the 74-week-old rats. PPI treatment reduced both commensal bacteria and opportunistic pathogens, particularly in the 2-year-old rats. Enterotypes comprising the majority of the control samples were enriched in Lactobacillus, while other enterotypes in the PPI group were dominated by Turicibacter or Romboutsia. The PPI treatment reduced the butyrate concentrations in the intestines and colons of 74-week-old rats compared to the control group. The abundance of Lactobacillus significantly correlated with butyrate concentrations in 74-week-old rats. In conclusion, long-term administration of PPIs alters the gut microbiota and butyrate concentrations in rats, particularly in old age, which may be an underlying mechanism of PPI-induced adverse effects such as pseudomembranous colitis.

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The total synthesis of nocarbenzoxazoles F (1) and G (2), originally obtained from the marine-derived halophilic bacterial strain Nocardiopsis lucentensis DSM 44048, was achieved via a simple and versatile route involving microwave-assisted construction of a benzoxazole skeleton, followed by carbon-carbon bond formation with the corresponding aryl bromides. Unfortunately, the 1H and 13C NMR spectra of natural nocarbenzoxazole G did not agree with those of the synthesized compound. In particular, the spectra of the isolated and synthesized compounds showed considerable differences in the signals from the protons and carbons in the aryl group. The revised structure was validated by the total synthesis of the actual nocarbenzoxazole G (8c) molecule, which is a regioisomer of the compound that was reported earlier as nocarbenzoxazole G. The synthesized derivatives showed specific cytotoxicity to the human cervical carcinoma cell line, HeLa, but did not have any remarkable effect on the other cell lines.

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BACKGROUND: High-fat diet is known to be implicated in the pathogenesis of various metabolic disorders related to an inflammatory response. The aim of this study was to investigate the influence of high-fat diet for intestinal acetic acid and butyric acid concentrations which are related to inflammation-associated colon cancer risk. METHODS: Both male and female rats of 6, 31, 74 and 104-week of age were fed chow diet or high-fat diet for 8 weeks. Body weight and food intake were measured weekly during the feeding period. Intestinal acetic acid and butyric acid levels were measured by high-performance liquid chromatography from luminal contents of ileum and cecum. RESULTS: Male rats showed greater weight change than female rats in every age. Calorie-adjusted food intake was also higher in male rats compared to female rats. Male rats showed similar intake of food in every age while 31-week old female rats showed increased intake, which was decreased at 74-week and 104-week of age. The ileal acetic acid concentration was increased in male rats fed high-fat diet, while female rats fed high-fat diet showed no significant change in the ileal acetic acid level. On the other hand, butyric acid almost disappeared in high-fat diet fed rats regardless of sex. CONCLUSIONS: High-fat diet increases the intestinal acetic acid concentration while reducing the butyric acid concentration which may account for increased risk of inflammation-associated colon cancer.

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To increase the contents of medicinally effective ginsenosides, we used high-temperature and high-pressure thermal processing of ginseng by exposing it to microwave irradiation. To determine the anti-melanoma effect, the malignant melanoma SK-MEL-2 cell line was treated with an extract of microwave-irradiated ginseng. Microwave irradiation caused changes in the ginsenoside contents: the amounts of ginsenosides Rg1, Re, Rb1, Rb2, Rc, and Rd were disappeared, while those of less polar ginsenosides, such as Rg3, Rg5, and Rk1, were increased. In particular, the contents of Rk1 and Rg5 markedly increased. Melanoma cells treated with the microwave-irradiated ginseng extract showed markedly increased cell death. The results indicate that the microwave-irradiated ginseng extract induced melanoma cell death via the apoptotic pathway and that the cytotoxic effect of the microwave-irradiated ginseng extract is attributable to the increased contents of specific ginsenosides.

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In this study, the effect of flue gas CO2 on growth, lipid production, and fatty acid composition of a green microalga Acutodesmus obliquus KGE 30 was investigated. The highest growth rate (0.46 g L(-1) and µmax = 1.09 day(-1)), total inorganic carbon removal (95.9 mg L(-1)), and lipid productivity (20.1 mg L(-1) day L(-1)) was obtained at 14.1 % CO2 after 4 days of cultivation. In a semicontinuous batch reactor, the highest biomass production (1.19 g L(-1)) was achieved after 12 days with continuous injection of flue gas CO2. Compared with synthetic CO2, fatty acid methyl ester analysis showed that the amount of unsaturated fatty acid increased by 19.2 % with 14.1 % flue gas CO2. The application of flue gas CO2 improved biomass production and lipid productivity in A. obliquus. The current investigation demonstrated that the use of flue gas CO2 could reduce the cost of microalgae biomass production for better biofuel generation.

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Immobilized microalgae using silica (IMS) from Micractinium reisseri KGE33 was synthesized through a sol-gel reaction. Green algal waste biomass, the residue of M. reisseri KGE33 after oil extraction, was used as the biomaterial. The adsorption of Cu(II) on IMS was tested in batch experiments with varying algal doses, pH, contact times, initial Cu(II) concentrations, and temperatures. Three types of IMSs (IMS 14, 70, and 100) were synthesized according to different algal doses. The removal efficiency of Cu(II) in the aqueous phase was in the following order: IMS 14 (77.0%) < IMS 70 (83.3%) < IMS 100 (87.1%) at pH 5. The point of zero charge (PZC) value of IMS100 was 4.5, and the optimum pH for Cu(II) adsorption was 5. Equilibrium data were described using a Langmuir isotherm model. The Langmuir model maximum Cu(II) adsorption capacity (q m) increased with the algal dose in the following order: IMS 100 (1.710 mg g(-1)) > IMS 70 (1.548 mg g(-1)) > IMS 14 (1.282 mg g(-1)). The pseudo-second-order equation fitted the kinetics data well, and the value of the second-order rate constant increased with increasing algal dose. Gibbs free energies (ΔG°) were negative within the temperature range studied, which indicates that the adsorption process was spontaneous. The negative value of enthalpy (ΔH°) again indicates the exothermic nature of the adsorption process. In addition, SEM-energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS) analyses of the IMS surface reveal that the algal biomass on IMS is the main site for Cu(II) binding. This study shows that immobilized microalgae using silica, a synthesized biosorbent, can be used as a cost-effective sorbent for Cu(II) removal from the aqueous phase.

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The biomass and lipid/carbohydrate production by a green microalga Scenedesmus obliquus under mixotrophic condition using food wastewater and flue gas CO2 with municipal wastewater was investigated. Different dilution ratios (0.5-2%) of municipal wastewater with food wastewater were evaluated in the presence of 5, 10 and 14.1% CO2. The food wastewater (0.5-1%) with 10-14.1% CO2 supported the highest growth (0.42-0.44 g L(-1)), nutrient removal (21-22 mg TN L(-1)), lipid productivity (10-11 mg L(-1)day(-1)) and carbohydrate productivity (13-16 mg L(-1)day(-1)) by S. obliquus after 6 days of cultivation. Food wastewater increased the palmitic and oleic acid contents up to 8 and 6%, respectively. Thus, application of food wastewater and flue gas CO2 can be employed for enhancement of growth, lipid/carbohydrate productivity and wastewater treatment efficiency of S. obliquus under mixotrophic condition, which can lead to development of a cost effective strategy for microalgal biomass production.

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Acid mine drainage sludge (AMDS) is a solid waste generated following the neutralization of acid mine drainage (AMD). This material entrapped in calcium alginate was investigated for the sorption of As(III) and As(V). Three different adsorbent materials were prepared: AMDS alginate beads (AABs), goethite alginate beads (GABs), and pure alginate beads. The effects of pH and the adsorption kinetics were investigated, and the adsorption isotherms were also evaluated. The optimum pH range using the AABs was determined to be within 2-10 for As(III) and 2-9 for As(V). Adsorption equilibrium data were evaluated using the Langmuir isotherm model, and the maximum adsorption capacity qmax was 18.25 and 4.97 mg g(-1) for As(III) on AAB and GAB, respectively, and 21.79 and 10.92 mg g(-1) for As(V) on AAB and GAB, respectively. The adsorption of As(III) and As(V) was observed to follow pseudo-second order kinetics. The As K-edge X-ray absorption near-edge structure (XANES) revealed that the adsorbed As(III) on the AABs was oxidized to As(V) via manganese oxide in the AMDS.

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