•Relationship between thermal annealing, sp2 domain, bandgap and properties in RGO.•Correlation between experimental data with calculations (GFN2-xTB, sTD-DFT).•The significant increase of 45.8% in ...the PEC hydrogen evolution for RGO1100 films.
The effect of thermal annealing on the recovery of sp2 carbon networks in the reduced graphene oxide (RGO) and its consequent bandgap enlargement and electrical conductivity improvement were thoroughly studied, experimentally and theoretically correlated. The annealed RGO film at 1100 °C (designated as RGO1100) exhibited a low sheet resistance (1250 Ω.cm−2) with a wide bandgap of 2.82 eV. The photoelectrochemical (PEC) experiments in 1 M H2SO4 solution under solar simulation light (1.5 AM) showed photocurrent densities of 48 and 70 μA.cm−2 for non-annealed RGO (72.5% sp2 fraction) and RGO1100 (87% sp2 fraction) respectively, equivalent to an increase of 45.8% for RGO1100. The bandgap widening as well as electrical conductivity increase of RGO1100 were closely interpreted on the basis of sp2 domain restoration, electronic and molecular orbital structures obtained from extensive experimental data as well as elaborated Geometry, Frequency, Noncovalent Extended Tight-binding (GFN2-xTB) and simplified Tamm-Dancoff density functional theory (sTD-DFT) calculations. The correlation between the electronic structure and the PEC performance of the RGO was also evaluated when the impact of the spatial distribution of oxidation and reduction regions on the recombination rate between photogenerated electrons and holes had been taken into account. The findings shed light on the structure-PEC relationship of RGO1100, which will definitely assist in designing and tailoring RGO-based, highly active materials for PEC applications.
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•Solvent-free synthesis of 2-arylbenzoxazole was catalyzed by Zr/Hf-MOFs.•MOF catalytic activity was enhanced by microwave irradiation.•Mechanism of ring open pathway acylation ...reaction under Zr/Hf-MOFs catalysis was described.•Catalytic activity of Zr-MOFs and Hf-MOFs was compared by experimental and computational studies.•The catalysts was recovered and reused in the reaction under microwave irradiation.
Zirconium- and hafnium-based metal–organic frameworks which constructed by 12-coordinated clusters and 6-coodinated clusters were shown to be highly effective heterogeneous catalysts for the ring opening acylation of benzoxazole to 2-arylbenzoxazole under solvent free conditions. Owning the wide opening spaces structures and inherent formate sites, MOFs based on 6-connected Zr6/Hf6 node were able to identify a significantly enhanced yield in Brønsted acid catalyzed reactions under conventional heating and microwave irradiation. In addition, the detailed mechanism of active sites of the ring opening acylation reaction was confirmed by employing of density functional theory (DFT) calculations.
Combining semiconductor and noble metal nanostructures into a hybrid system has shown many complementary advantages in the optical properties, making them more attractive in practical applications. ...Herein, we prepared a semiconductor/noble metal hybrid system composed of Ag nanoparticles decorated on ZnO nanoplates acting as a surface-enhanced Raman scattering (SERS) substrate for probing methyl red. The tuning of the optical characteristics of the hybrid system was demonstrated through the changes in the absorption, fluorescence, and Raman spectra. The formation of the local electromagnetic field at the heterostructure interface plays a pivotal role in its SERS activity. Thanks to density functional theory calculations, methyl red's vibrational modes and symmetry properties were assigned to be consistent with the contribution of the neutral
trans
conformer and protonated state. Then, using Herzberg-Teller-surface selection rules, these assignments strongly support the realization that the SERS mechanism based on the ZnO/Ag substrate has a significant electromagnetic contribution
versus
the Ag substrate in which charge transfer plays a pivotal role. To the best of our knowledge, this is the first investigation that has clarified the mechanism and advantage of semiconductor/metal (ZnO/Ag nanostructures) even over noble metals (Ag nanoparticles) in SERS applications. Moreover, the SERS behavior based on the ZnO/Ag substrate was also examined and the results indicated high sensitivity and good repeatability.
Using Herzberg-Teller-surface selection rules in combination with the results of DFT calculations, the SERS mechanism based on the ZnO/Ag substrate has indicated a significant electromagnetic contribution
versus
the Ag substrate, in which charge transfer plays a pivotal role.
Flexible bronchoscopy has revolutionized respiratory disease diagnosis. It offers direct visualization and detection of airway abnormalities, including lung cancer lesions. Accurate identification of ...airway lesions during flexible bronchoscopy plays an important role in the lung cancer diagnosis. The application of artificial intelligence (AI) aims to support physicians in recognizing anatomical landmarks and lung cancer lesions within bronchoscopic imagery. This work described the development of BM-BronchoLC, a rich bronchoscopy dataset encompassing 106 lung cancer and 102 non-lung cancer patients. The dataset incorporates detailed localization and categorical annotations for both anatomical landmarks and lesions, meticulously conducted by senior doctors at Bach Mai Hospital, Vietnam. To assess the dataset's quality, we evaluate two prevalent AI backbone models, namely UNet++ and ESFPNet, on the image segmentation and classification tasks with single-task and multi-task learning paradigms. We present BM-BronchoLC as a reference dataset in developing AI models to assist diagnostic accuracy for anatomical landmarks and lung cancer lesions in bronchoscopy data.
The Warburg effect is a tumor-related phenomenon that could potentially be targeted therapeutically. Here, we showed that glioblastoma (GBM) cultures and patients' tumors harbored super-enhancers in ...several genes related to the Warburg effect. By conducting a transcriptome analysis followed by ChIP-Seq coupled with a comprehensive metabolite analysis in GBM models, we found that FDA-approved global (panobinostat, vorinostat) and selective (romidepsin) histone deacetylase (HDAC) inhibitors elicited metabolic reprogramming in concert with disruption of several Warburg effect-related super-enhancers. Extracellular flux and carbon-tracing analyses revealed that HDAC inhibitors blunted glycolysis in a c-Myc-dependent manner and lowered ATP levels. This resulted in the engagement of oxidative phosphorylation (OXPHOS) driven by elevated fatty acid oxidation (FAO), rendering GBM cells dependent on these pathways. Mechanistically, interference with HDAC1/-2 elicited a suppression of c-Myc protein levels and a concomitant increase in 2 transcriptional drivers of oxidative metabolism, PGC1α and PPARD, suggesting an inverse relationship. Rescue and ChIP experiments indicated that c-Myc bound to the promoter regions of PGC1α and PPARD to counteract their upregulation driven by HDAC1/-2 inhibition. Finally, we demonstrated that combination treatment with HDAC and FAO inhibitors extended animal survival in patient-derived xenograft model systems in vivo more potently than single treatments in the absence of toxicity.
To evaluate the efficacy of fermented milk containing Lactobacillus casei strain Shirota (LcS) on the incidence of constipation, diarrhea, acute respiratory infections (ARI), and nutritional status ...of young Vietnamese children.
A controlled field trial was conducted with 1003 children (3-5 years old) in Thanh Hoa province in Vietnam. The probiotic group (n = 510) consumed fermented milk 65 mL/day containing 10
CFU/mL of LcS for the 12-week intervention period, whereas the control group (n = 493) was not given any. The incidence of constipation, diarrhea, ARI, and anthropometry in children was determined at baseline, after 4, 8, and 12-week intervention, and after the 4-week follow-up period.
Probiotic drink decreased the incidence of constipation after the 12-week intervention period (12.0% vs. 32.0%, OR = 0.28 (95% CI: 0.21-0.40), p < 0.001), tended to decrease the incidence of diarrhea (4.9% vs. 7.9%, OR = 0.60 (95% CI: 0.35-1.01), p = 0.068), and prevented the occurrence of ARI (15.9% vs. 24.5%, OR = 0.58 (95% CI: 0.42-0.79), p < 0.001), when compared with the control group. In contrast, no probiotic effects were observed for the duration of diarrhea or ARI. Weight gain was higher in the probiotic group than in the control group after 4, 8, and 12-week intervention and after the 4-week follow-up period (p < 0.05).
Daily intake of fermented milk containing LcS strongly prevented the incidence of constipation and ARI in Vietnamese children. This study also revealed the potential effects of the use of a probiotic drink on diarrhea prevention as well as nutritional status improvement.
A new isopropyl chromone (1) and a new flavanone glucoside (2) together with eleven known compounds (3–13) were isolated from the leaves of Syzygium cerasiforme (Blume) Merr. & L.M.Perry. Their ...structures were elucidated as 5,7‐dihydroxy‐2‐isopropyl‐6,8‐dimethyl‐4H‐chromen‐4‐one (1), 5,7‐dihydroxyflavanone 7‐O‐β‐D‐(6′′‐O‐galloylglucopyranoside) (2), strobopinin (3), demethoxymatteucinol (4), pinocembrin‐7‐O‐β‐D‐glucopyranoside (5), (2S)‐hydroxynaringenin‐7‐O‐β‐D‐glucopyranoside (6), afzelin (7), quercetin (8), kaplanin (9), endoperoxide G3 (10), grasshopper (11), vomifoliol (12), litseagermacrane (13) by the analysis of HR‐ESI‐MS, NMR, and CD spectral data. Compounds 1, 2, 5, 6 and 10 inhibited NO production on LPS‐activated RAW264.7 cells with IC50 values of 12.28±1.15, 8.52±1.62, 7.68±0.87, 9.67±0.57, and 6.69±0.34 μM, respectively, while the IC50 values of the other compounds ranging from 33.38±0.78 to 86.51±2.98 μM, compared to that of the positive control, NG‐monomethyl‐L‐arginine acetate (L‐NMMA) with an IC50 value of 32.50±1.00 μM.
Summary
A commercial cellulase preparation (Viscozyme Cassava C) was employed to process wheat bran to improve the ratio of insoluble to soluble dietary fibre. The effects of initial moisture ...content, enzyme dosage, and incubation time on the content of soluble and insoluble fibre during the enzymatic treatment were investigated. The appropriate conditions for the cellulase treatment were initial moisture content of 0.75 g water g−1 dry matter, enzyme dosage of 9 U g−1 dry matter and incubation time of 120 min under which the ratio of insoluble to soluble fibre of wheat bran was lowered by 42%. Untreated and cellulase‐treated wheat bran was incorporated into cookies at levels of 0%, 20%, 30%, 40% and 50%. Cookie with 50% cellulase‐treated bran showed 21% lower ratio of insoluble to soluble fibre as well as 14% lower hardness and 13% higher overall acceptability than sample with the same amount of untreated bran.
Wheat bran was processed with a cellulase preparation and incorporated into cookie. The effects of treatment conditions on dietary fibre content were evaluated. Incorporation of cellulase‐treated bran augmented soluble fibre content of cookie. Hardness of cookie from treated bran was lower than that from untreated one.
Decorating two-dimensional (2D) nanomaterials with nanoparticles provides an effective method to integrate their physicochemical properties. In this work, we present the hydrothermal growth process ...of 2D zinc oxide nanoplates (ZnO NPls), then silver nanoparticles (AgNPs) were uniformly distributed on the surface of ZnO NPls through the reduction procedure of silver nitrate with sodium borohydride to create a metal-semiconductor hybrid. The amount of AgNPs on the ZnO NPls' surface was carefully controlled by varying the volume of silver nitrate (AgNO
3
) solution. Moreover, the effect of AgNPs on the surface-enhanced Raman scattering (SERS) property of ZnO NPls was thoroughly investigated by using methylene blue (MB) as the target molecule. After calculation, the maximum enhancement factor value for 10
−4
M of MB reached 6.2 × 10
6
for the peak at 1436 cm
−1
and the limit of detection was 10
−9
M. In addition, the hybrid nanosystem could distinguish MB with good reproducibility over a wide range of concentrations, from 10
−9
to 10
−4
M. The SERS mechanism is well elucidated based on the chemical and electromagnetic mechanisms related to the synergism of ZnO and Ag in the enhancement of Raman signal. Abundant hot spots located at the gap between adjacent separate Ag nanoparticles and ZnO nanoplates which formed a strong local electromagnetic field and electron transfer between ZnO and Ag are considered to be the key factors affecting the SERS performance of our prepared ZnO/Ag substrates. In this research, we found high sensitivity of ZnO nanoplates/Ag nanoparticles in detecting MB molecules. This unique metal-semiconductor hybrid nanosystem is advantageous for the formation of Raman signals and is thus suitable for the trace detection of methylene blue.
Decorating two-dimensional (2D) nanomaterials with nanoparticles provides an effective method to integrate their physicochemical properties.
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