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Facet regulation of the BiVO4 photoanode is an effective way to improve its charge separation efficiency. Herein, a BiVO4 photoanode structured by connecting a (040)-facet-oriented mono-grain layer...

Background: Pre-existing liver disease is a risk factor for the worse prognosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We aimed to evaluate whether chronic hepatitis B (CHB) and hepatocellular carcinoma (HCC) affect the expression of viral receptor angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) in the liver. Methods: Twelve pairs of matched liver tissues of HCC and para-carcinoma were collected from the First Affiliated Hospital of Zhejiang University School of Medicine. And 20 liver biopsies from CHB patients were collected from Peking University People's Hospital. The expression of ACE2 and TMRPSS2 were detected using immunofluorescence staining, western blot, and RT-qPCR. The effects of hepatitis B virus (HBV) replication or interferon on ACE2 and TMPRSS2 expression were tested in hepatic cell lines. Results: The mRNA expression of TMPRSS2 in HCC tissues was six-fold higher than that of para-carcinoma tissues (P = 0.002), whereas that of ACE2 was not statistically different between HCC and para-carcinoma tissues. Hepatocellular ACE2 expression was detected in 35% (7/20) of CHB patients and mostly distributed in the inflammatory areas. However, there was no difference in TMPRSS2 expression between areas with or without inflammation. IFN-α2b slightly induced ACE2 expression (2.4-fold, P = 0.033) in HepG2 cells but not in Huh-7, QSG-7701, and L-02 cells. IFN-α2b did not affect TMPRSS2 expression in these cell lines. In addition, HBV replication did not alter ACE2 expression in HepAD38 cells. Conclusions: Although HBV replication does not directly affect the expression of ACE2 and TMPRSS2, intrahepatic inflammation and carcinogenesis may increase their expression in some patients, which, in turn, may facilitate SARS-CoV-2 infection in hepatocytes.

A Cu2O/Pt/BiVO4 heterojunction was prepared by successively depositing Pt and Cu2O nanoparticles on {010} facets of BiVO4, showing much higher photocatalytic activity in hydrogen evolution than that constructed by random deposition of Cu2O on all facets of BiVO4 particles. Photoluminescence spectroscopy revealed that the facet-selective Cu2O/Pt/BiVO4 arrays effectively promoted charge separation of the BiVO4 host. A band alignment was consequently presented to illustrate the interface charge flow in the heterojunction. This work demonstrates the roles that facets played in semiconductor heterojunctions applied to photocatalytic reactions.

Synthesis of diethyl carbonate (DEC) in the liquid phase by oxidative carbonylation of ethanol over activated carbon (AC)-supported chloride-free Cu-based catalysts offers a prospective “green chem...

Impacts of galling on the distributions of plant metabolites can vary greatly with plant genotype. In this study, two Eucalyptus genotypes with different resistance levels were chosen, and the levels of several primary and secondary metabolites, as well as phytohormones in galls and ungalled portions of galled leaves infested by the gall wasp Leptocybe invasa, and gall-free (control) leaves were compared. It was found that galls of both two plant genotypes accumulated higher concentrations of carbon, total phenolics, gibberellins (GA), and abscisic acid (ABA) but had lower chlorophyll content than ungalled portions. However, galls of highly susceptible genotype contained higher nitrogen (N), cytokinins (CK), GA, and chlorophyll content but lower C/N ratio, total phenolics, tannins, and ABA than less susceptible genotype. For both two genotypes, ABA in galls and ungalled portions increased compared with adjacent control leaves. CK and GA levels increased in galls but decreased in ungalled portions of highly susceptible genotype, compared with control leaves. For less susceptible genotype, CK levels increased in both galls and ungalled portions compared with control leaves, but higher levels of tannins, total phenolics, and GA were only detected in galls. Therefore, our study found insufficient evidence that the impact of galling on the distributions of these metabolites and phytohormones extended beyond the attacked leaves, because they varied greatly with plant genotype.

2,5-Diethyl-1,4-benzenedinitrile N-oxide was designed and synthesized to achieve room temperature curing of hydroxyl-terminated polybutadiene binders. The structures and properties of the four cured elastomers having different content of curing agent were investigated. The results showed that the isoxazoline rings from the reaction of nitrile N-oxide with cis-alkene are observed in the four cured elastomers. The results also revealed that the hydroxyl-terminated polybutadiene with the lowest content of curing agent showed the lowest cross-linking density and stress at break. The proper activity and steric hindrance of 2,5‑diethyl-1,4-benzenedinitrile N-oxide gave better mechanical properties and hydrophobic properties of the cured elastomers than nitrile N-oxide prepared by our previous work.

The chemical compositions of essential oils (EOs) prepared from six spices including cinnamon, amomum tsao-ko, cardamom, amomum, black pepper and white pepper were analyzed by gas chromatography-mass spectrometry (GC-MS), which led to identify almost 200 volatile compounds. All EOs of spices showed cholinesterase inhibitory activity. Among them, pepper EO showed most potent acetylcholinesterase (AChE) inhibitory activity with IC 50 values of 8.54 μg/mL (black pepper EO) and 5.02 µg/mL (white pepper EO). Molecular docking and in vitro validation suggested that 3-carene, α -pinene and β -pinene with IC 50 value of 1.73, 2.66, and 14.75 μg/mL, respectively, might be active constituents of spices oil in inhibiting AChE. Furthermore, amomum tsao-ko EO and amomum EO can improve behavioral disorder in dementia zebrafish induced by aluminum trichloride (AlCl 3 ).

The circadian clock coordinates biological and physiological functions to day/night cycles. The perturbation of the circadian clock increases cancer risk and affects cancer progression. Here, we studied how BMAL1 knockdown (BMAL1-KD) by shRNA affects the epithelial–mesenchymal transition (EMT), a critical early event in the invasion and metastasis of colorectal carcinoma (CRC). In corresponding to a gene set enrichment analysis, which showed a significant enrichment of EMT and invasive signatures in BMAL1_high CRC patients as compared to BMAL1_low CRC patients, our results revealed that BMAL1 is implicated in keeping the epithelial–mesenchymal equilibrium of CRC cells and influences their capacity of adhesion, migration, invasion, and chemoresistance. Firstly, BMAL1-KD increased the expression of epithelial markers (E-cadherin, CK-20, and EpCAM) but decreased the expression of Twist and mesenchymal markers (N-cadherin and vimentin) in CRC cell lines. Finally, the molecular alterations after BMAL1-KD promoted mesenchymal-to-epithelial transition-like changes mostly appeared in two primary CRC cell lines (i.e., HCT116 and SW480) compared to the metastatic cell line SW620. As a consequence, migration/invasion and drug resistance capacities decreased in HCT116 and SW480 BMAL1-KD cells. Together, BMAL1-KD alerts the delicate equilibrium between epithelial and mesenchymal properties of CRC cell lines, which revealed the crucial role of BMAL1 in EMT-related CRC metastasis and chemoresistance.

(±)-Eurotone A [(±)- 1 ], a pair of new enantiomeric polyketide dimers, as well as six known biogenetically related polyketides ( 2 – 7 ) were isolated from a marine-derived fungus Eurotium sp. SCSIO F452. Their structures were determined by comprehensive spectroscopic methods, X-ray diffraction and quantum chemical calculations. Compound 1 represented the first pair of spirodihydrobenzanthracene enantiomers isolated from marine fungi with their absolute configurations assigned. A plausible biosynthetic pathway involving a key acid-mediated dimerization was proposed for 1 . The antioxidative activities of the new enantiomers were evaluated.

A new butenolide derivative (±)-asperteretal F (1) and related congener (2) recently reported containing an unusual 2-benzyl-3-phenyl substituted lactone core, together with five known compounds (3–7) were isolated and characterized from the fungus Aspergillus terreus. SCSIO FZQ028 derived from a deep-sea sediment of South China Sea. Their chemical structures were established on the basis of 1D- and 2D-NMR spectroscopic data, and HR-ESI-MS analysis. Additionally, all the compounds were evaluated for the antioxidative activities against DPPH, cytotoxic activities against two tumor cell lines (SF-268 and HepG-2), and antimicrobial activities. Compounds 2-4, and 7 showed significant activities against DPPH with IC50 ranging from 5.89 to 10.07 μg/mL. Compounds 2 and 4 showed moderate antimicrobial activities against all four tested bacteria.

Chiral sulfinamides are increasingly recognizedfor their extensive potential applications in chemistry, medicine and material science, yet chromatographic study on these compounds is seldom. In this article, we describe the enantioseparation of twelve closely related chiral sulfinamide derivatives on polysaccharide-based chiral stationary phases (CSPs). We investigated the factors affecting separation, such as the types of chiral columns, the concentration of polar alcohol and the column temperature. The acyclic sulfinamide derivatives-with the exception of a cyclic sulfinamide compound-were effectively resolved with a Chiralcel OD-H column and a mixture of n-hexane:isopropyl alcohol (90:10) as the mobile phase. All compounds except N-benzylidene-2-methylpropane-2-sulfinamide are baseline resolved on the Chiralpak AD-H column, but only eight compounds are resolved on a Chiralpak AS-H column under the given chromatographic conditions. This study offers valuable guidance for future chiral HPLC studies related to chiral sulfinamides.

A synergistic process adding peracetic acid (PAA) in electrochemistry (EC) was established to eliminate organic contaminants in water as a novel advanced oxidation process (AOP). The introduced PAA could be activated by the EC system, substituting electrolyte and promoting the methylene blue (MB) removal than the sole PAA and conventional EC systems. A series of scavenging tests demonstrated that the activation products were hydroxyl radical (HO·) and organic radicals (R-O·) in this EC/PAA process, which both played the dominant role for the MB decontamination. The effect of PAA dose, current density, initial pH, and initial MB concentration on the MB decolorization were investigated, and the results indicated that 93.99% MB was removed with the optimized conditions of 3.6 mmol L−1 PAA, 7.5 mmol L−1 H2O2, initial pH 3, and 10 mg L−1 MB concentration. The influence of water matrix (Cl−, HCO3−, SO42−, and humic acid) for removing MB was determined, and the results showed that the MB removal was considerably inhibited by these constituents of water. Lastly, the decomposition mechanism for the MB was suggested through the outcome of mass spectrometry. This study demonstrated that the EC/PAA process could be a feasible method, advancing the development of AOP for water treatment.

Chlorhexidine (CHX)/β-cyclodextrin (β-CD) inclusion and chitosan nanoparticles containing bovine serum albumin (CS/BSA) were blended into chitosan acetic acid solution respectively or simultaneously to prepare a novel thermosensitive hydrogel dual sustained-release system. Rheological properties, release, cytocompatibility, and antibacterial activity were investigated. The results confirmed that CHX/β-CD and CS/BSA were well dispersed in the solution, and the rheological property of hydrogel was not affected. The system exhibited promising dual sustained release and cytocompatibility. Antibacterial results showed that CHX-loaded hydrogel had a desirable therapeutic effect on Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli).

A pair of stereoisomers of new 4,5-dihydroxypiperine was isolated from P. retrofractum and showed profound activity on AlCl3-induced dementia. In order to determine their absolute configurations and biological activities, all four possible stereoisomers of 4,5-dihydroxypiperine were synthesized from piperidine by Sharpless asymmetric dihydroxylation and Mitsunobu reaction. Their absolute configurations were established as (4R,5R) (1), (4S,5S) (2), (4S,5R) (3) and (4R,5S) (4) by NMR, optical rotation and CD spectra. It is note that only compound 4 improved behavioral disorder in AlCl3-induced dementia. Accordingly, the pair of stereoisomers isolated from P. retrofractum was determined to be (4S,5S) and (4R,5S)-isomers (2 and 4). The ratio of the epimers was present as 1:0.7 (4:2).

Three new tricyclic cyclopiazonic acid (CPA) related alkaloids asperorydines N-P (1–3), together with six known compounds (4–9) were isolated and characterized from the fungus Aspergillus flavus SCSIO F025 derived from the deep-sea sediments of South China Sea. The structures including absolute configurations of 1–3 were deduced from spectroscopic data, X-ray diffraction analysis, and electronic circular dichroism (ECD). All compounds were evaluated for the antioxidative activities against DPPH, cytotoxic activities against four tumor cell lines (SF-268, HepG-2, MCF-7, and A549), and antimicrobial activities. Compound 9 showed significant radical scavenging activities against DPPH with an IC50 value of 62.23 μM and broad-spectrum cytotoxicities against four tumor cell lines with IC50 values ranging from 24.38 to 48.28 μM. Furthermore, compounds 4–9 exhibited weak antimicrobial activities against E scherichia coli, and compound 9 also showed antibacterial activity against Bacillus thuringiensis, Micrococcus lutea, Staphylococcus aureus, Bacillus subtilis, Methicillin resistant Staphylococcus aureus.

The aim of the present work is to investigate the effects of SiO2 content on the structure of CaO–B2O3–SiO2–Al2O3–ZnO glass using the MAS-NMR, the fourier transform infrared spectrometer and differential scanning calorimetry (DSC). The results showed that the majority of Al existed in fourfold coordination and Zn acted as glass modifier in glass structure. With the increasing of SiO2 content, the relative amount of BIII units decreased while the BIV units increased and the proportion of Si–O–Si bridge oxygen bond in [SiO4] tetrahedrons increased obviously. The DSC curves revealed that the glass transition temperature increased from 732 to 773 °C with the increasing of SiO2 content, indicating that SiO2 generating more bridge oxygen can increase the degree of polymerization of glass structure.

Pepper is one of the most popular spices over the world and is called the King of Spices. Its essential oils (EOs) could alleviate neuronal ailments due to the inhibitory effect against acetylcholinesterase (AChE). In this study, the chemical compositions of 26 EOs prepared from white and black pepper collecting from 6 different cultivars were analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 133 compounds were identified in the white and black pepper EOs. Monoterpenes and sesquiterpenes were found to be riched in these EOs, of which α-pinene, β-pinene, sabinene, 3-carene, limonene, and ( E)- β-caryophyllene were the major constituents. Most of pepper EOs showed potential AChE inhibitory activity with half-maximal inhibitory concentration (IC50) values in the range of 0.5-182.5 µg/mL. Comparison of chemical constitutes of pepper EOs from different cultivars suggested that α-pinene, β-pinene, and 3-carene with an IC50 value of 3.2, 53.3, and 2.9 µg/mL, respectively, might be used as Quality-marker (Q-marker) of pepper oil in inhibiting AChE.

The Ba2+ doped ceramics of Ca1−xBaxCu3Ti4O12 (x = 0.005, 0.01, 0.03, 0.05 and 0.1) were sintered via conventional solid-state reaction at 1050 °C for 8 h in air. The microstructure and electric properties of Ba2+ doping ceramics were investigated. The lattice parameters of Ca1−xBaxCu3Ti4O12 (CBCTO) ceramics decreased with the Ba2+ doping, and Ba1.31Ti8O16 as secondary phase was confirmed at x = 0.1. The doping of Ba2+ resulted in uniformly distribution of small size grain (~4 μm). All the doped samples showed lower value of dielectric constant than CaCu3Ti4O12 (CCTO), due to low resistivity of the grain boundary with the Ba2+ doped samples. The nonlinear coefficient and breakdown field were significantly enhanced by Ba2+ doping.

An ensemble method based on supervised learning for segmenting the retinal vessels in color fundus images is proposed on the basis of previous work of Zhu et al. For each pixel, a 36 dimensional feature vector is extracted, including local features, morphological transformation with multi-scale and multi-orientation, and divergence of vector field which is firstly used to extract feature of retinal image pixels. Then the feature vector is used as input data set to train the weak classifiers by the Classification and regression tree (CART). Finally, an AdaBoost classifier is constructed by iteratively training for the retinal vessels segmentation. The experimental results on the public Digital retinal images for vessel extraction (DRIVE) database demonstrate that the proposed method is efficient and robust on the fundus images with lesions when compared with the other methods. Meanwhile, the proposed method also exhibits high robustness on a new Retinal images for screening (RIS) database. The average accuracy, sensitivity, and specificity of improved method are 0.9535, 0.8319 and 0.9607, respectively. It has potential applications for computer-aided diagnosis and disease screening.

Three pairs of spirocyclic diketopiperazine enantiomers, variecolortins A-C (1-3), were isolated from marine-derived fungus Eurotium sp. SCSIO F452. Compound 1 possesses an unprecedented highly functionalized seco-anthronopyranoid carbon skeleton featuring a 2-oxa-7-azabicyclo[3.2.1]octane core. Compounds 2 and 3 represent rare examples of a 6/6/6/6 tetracyclic cyclohexene-anthrone carbon scaffold. Their structures were determined by spectroscopic analyses, X-ray diffraction, and ECD calculations. Their enantiomers exhibited different antioxidative and cytotoxic activities, and their modes of action were investigated.

Three new prenylated indole 2,5-diketopiperazine alkaloids (1–3) with nine known ones (5–13), one new indole alkaloid (4), and one new bis-benzyl pyrimidine derivative (14) were isolated and characterized from the marine-derived fungus Eurotium sp. SCSIO F452. 1 and 2, occurring as a pair of diastereomers, both presented a hexahydropyrrolo[2,3-b]indole skeleton. Their chemical structures, including absolute configurations, were elucidated by 1D and 2D NMR, HRESIMS, quantum chemical calculations of electronic circular dichroism, and single crystal X-ray diffraction experiments. Most isolated compounds were screened for antioxidative potency. Compounds 3, 5, 6, 7, 9, 10, and 12 showed significant radical scavenging activities against DPPH with IC50 values of 13, 19, 4, 3, 24, 13, and 18 µM, respectively. Five new compounds were evaluated for cytotoxic activities.

Summary Aims Studies showed fastigial nucleus stimulation (FNS) reduced brain damage, but the mechanisms of neuroprotection induced by FNS were not entirely understood; MicroRNAs are noncoding RNA molecules that regulate gene expression in a posttranscriptional manner, but their functional consequence in response to ischemia–reperfusion (IR) remains unknown. We investigated the role of microRNA-29c in the neuroprotection induced by FNS in rat. Methods The IR rat models were conducted 1 day after FNS. Besides, miR-29c antagomir (or agomir or control) was infused to the left intracerebroventricular 1 day before IR models were conducted. We detected differential expression of Birc2 mRNA (also Bak1mRNA and miR-29c) level among different groups by RT-qPCR. The differential expression of Birc2 protein (also Bak1 protein) level among different groups was surveyed via Western blot. The neuroprotective effects were assessed by infarct volume, neurological deficit, and apoptosis. Results MiR-29c was decreased after FNS. Moreover, miR-29c directly bound to the predicted 3′-UTR target sites of Birc2 and Bak1 genes. Furthermore, over-expression of miR-29c effectively reduced Birc2 (also Bak1) mRNA and protein levels, increased infarct volume and apoptosis, and deteriorated neurological outcomes, whereas down-regulation played a neuroprotective role. Conclusions MiR-29c correlates with the neuroprotection induced by FNS by negatively regulating Birc2 and Bak1.

(CoxNi1−x)0.85Se nanostructures (NSs) with different shapes (i.e., sheet-like, flower-like, and urchin-like) were synthesized by a sacrificial template method. As far as we know, this paper may be the first work that used (CoxNi1−x)0.85Se NSs as catalysts for reduction of 4-nitrophenol (4-NP) by NaBH4 in aqueous solution.

This study demonstrated the preparation of Co0.85Se bundle-like nanostructures (BNs) by a template-directed approach under solvothermal conditions. The Co0.85Se BNs were utilized as catalysts in the reduction of 4-nitrophenol in the presence of NaBH4. The kinetics of the reduction of 4-nitrophenol at three different reaction temperatures were investigated to evaluate the catalytic activity of the Co0.85Se BNs. The activation energy (Ea), activation enthalpy (ΔH‡), and activation entropy (ΔS‡) of the Co0.85Se BNs and Co0.85Se nanoparticles (NPs) are 14.66 kJ mol−1, 12.15 kJ mol−1, 42.51 J mol−1 K−1, and 17.78 kJ mol−1, 16.55 kJ mol−1, 50.66 J mol−1 K−1, respectively. The above results revealed that the Co0.85Se BNs exhibited a higher catalytic performance for the hydrogenation of 4-nitrophenol by NaBH4 than that of the Co0.85Se NPs at room temperature. It is believed that the prepared Co0.85Se BNs have potential applications in catalysis.

In this study, CoNi2S4 microstructures (CoNi2S4 MSs) with urchin-like and flower-like shapes were synthesized by a sacrificial template method based on the Kirkendall effect. The as-prepared CoNi2S...

This study was carried out to determine major nutrient profiles changes of tiger nut plant during its growth period. The plant leaves, roots, tuber moisture, starch, fat and protein were analyzed by oven drying, enzymatic hydrolysis, glucose assay, soxhlet extraction and kjeldahl methods. The results show the moisture content was decreased during its growth cycle but varied with different plant organ. For leaves, the starch content was increased with reducing oil content. For roots, oil content was highest (8%) at the 100th day, and it was gradually decreased (3%) till harvest time with non-significant changes of starch content. For tuber, reducing sugar and protein content was insignificant where the starch and oil content increased significantly but the changes were irregular in the middle growing. For optimum macronutrient yields, it is recommended to harvest the plant at 142nd day for starch. The delayed harvesting may lead to increase in oil content while reducing its total starch contents. For the starch purpose, the harvest time could be around 142 days. However, harvest time could require staying longer in soil. Keywords: Tiger nut, oil, starch, growth cycle, nutrients enrichment

Water content of Korean pine samples was studied using near infrared spectrascopy (NIR) combinded with parial least squares regression (PLS) analysis. Seven typical wave lengths were selceted to characterize the wood water content of Korean pine. Prediction models of wood water content were developed based on the original NIR spectra at seven varied wave lengths. The best model was showed between wavelengths from 1000 to 2100 nm with correlation coefficient (R) of 0.9871, standard error of calibration (SEC) and root mean square error of calibration (RMSEC) of 0.0337 and 0.0334, respectively. The correlation coefficient（R） for model validation was 0.9817 with standard error of prediction (SEP) and root mean square error of prediction (RMSEP) of 0.0470 and 0.0465, respectively. This study indicated that NIR is a useful tool for fast prediction of wood water content of Korean pine. The modeling proficiency could be improved significantly for some certain wave length. It could be a research focus for future related studies.