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Hydrogen production through photoelectrochemical (PEC) reactions is an innovative and promising approach to producing clean energy. The PEC working electrode of a Co3O4/ZnO-based p-n heterojunction was prepared by a straightforward electrochemical deposition with different deposition times onto an FTO (Fluorine-doped Tin Oxide) glass substrate. The successful synthesis of the materials was confirmed through analysis using XRD, FTIR, SEM-EDX, DRS, and PL techniques. Mott-Schottky plots and some characterization studies also checked the determination of the formation of the p-n junction. Co3O4/ZnO/FTO with a Co3O4 deposition time of 2 minutes exhibited the lowest onset potential of 0.82 V and the lowest overpotential of 470 mV at a current density of 10 mA cm -2. Furthermore, the photo-conversion efficiency of the Co3O4/ZnO/FTO sample showed 1.4 times higher current density than the ZnO/FTO sample. A mechanism is also proposed to enhance the Co3O4/ZnO/FTO electrode photo-electrocatalytic activity involved in the water-splitting reaction. The Co3O4/ZnO/FTO electrode shows significant potential as a promising PEC electrode to produce hydrogen.

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The increasing prevalence of pharmaceutical contaminants in aquatic ecosystems poses profound challenges for both environmental sustainability and public health. Addressing this pressing issue requires the development of innovative, cost-effective, and efficient remediation approaches. Here we report the synthesis of WO3/diatomite composites and their photocatalytic degradation in conjunction with potassium peroxymonosulfate (PMS) activation. By leveraging the synergistic effects, we observe a remarkable degradation of tetracycline, a significant pharmaceutical contaminant, under visible light. Analytically, we have elucidated the driving factors for the enhanced performance, emphasizing the optimal amount of WO3 (10%) in the composite and PMS concentration (3 mM). Specifically, the WO3/diatomite catalyst presents a degradation rate of 80.75% tetracycline (40 mg L-1) after 180 min of visible light irradiation. Also, we elucidate the primary roles of ˙SO4 - radicals in driving the photocatalytic reaction using free radical trapping studies. Our approach not only offers a direct solution to controlling pharmaceutical contamination but also opens new possibilities for advancing the design of composite-based photocatalysts by taking advantage of nature-derived materials.

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In this study, the anti-osteogenic properties of the volatile oil extracted from Homalomena gigantea rhizome using ethyl acetate (EtOAc) and methanol (MeOH) were examined. Gas chromatography-mass spectrometry (GC-MS) was employed for the identification of volatile components. Following this, bioassays were performed to evaluate their effects on osteogenesis, encompassing parameters like cell viability, osteoblast differentiation, collagen synthesis and mineralization. The GC-MS analysis revealed 19 compounds in the EtOAc extract and 36 compounds in the MeOH extract. In the MeOH extract, major constituents included bis(2-ethylhexyl) terephthalate (13.83%), linalool (9.58%), palmitic acid (6.55%) and stearic acid (4.29%). The EtOAc extract contained bis(2-ethylhexyl) terephthalate (16.64%), palmitic acid (5.60%) and stearic acid (3.11%) as the predominant components. Both the EtOAc and MeOH extracts of H. gigantea exhibited promising potential for further investigation in anti-osteoporosis research. These findings contribute to the exploration of natural compounds with potential anti-osteoporotic properties, expanding our understanding of their therapeutic potential.

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Non-Hodgkin lymphoma (NHL) is a lymphoproliferative disorder derived from either B or T lymphocytes. Among NHL, activated B-cell-like (ABC) diffuse large B-cell lymphoma (DLBCL) and T cell non-Hodgkin lymphomas (T-NHL) are poor prognosis and aggressive subtypes. Macrophages are professional phagocytic cells and dendritic cells (DCs) are professional antigen-presenting cells in immune system. Doxorubicin (Dox) and Etoposide (ET) are the most effective anti-cancer drugs. A20 and CYLD are negative regulators of NF-κB-dependent functions in many cell types. Little is known about the roles of A20 and CYLD in regulating functions of DCs and macrophages from NHL. The present study, therefore, explored whether A20/CYLD expression contributes to functions of DCs and macrophages from NHL. To this end, blood samples of seventy-nine patients with ABC DLBCL and T-NHL were examined. Gene expression profile was determined by quantitative RT-PCR and immunophenotype, cell apoptosis and phagocytosis by flow cytometry. As a result, immunophenotypic analysis showed that the numbers of CD13+CD117-, CD56+CD40+ and CD23+CD40+ expressing cells were significantly elevated in ABC DLBCL cases compared to healthy individuals and T-NHL patients. Interestingly, upon treatment of Dox and ET, the phagocytosis of lymphoma cells was significantly reduced by CD11c+CD123- DCs and the percentage of CD56+ mature DCs was significantly enhanced in ABC DLBCL patients only in the presence of A20 siRNA, but not CYLD siRNA. In conclusion, ABC DLBCL patients with low A20 expression were defective in elimination of lymphoma cells by DCs and linked to killer DC expansion in circulation.

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The treatment or conversion of air pollutants with a low generation of secondary toxic substances has become a hot topic in indoor air pollution abatement. Herein, we used triangle-shaped Ag nanoparticles coupled with SnO2 for efficient photocatalytic NO removal. Ag triangular nanoparticles (TNPs) were synthesized by the photoreduction method and SnO2 was coupled by a simple chemical impregnation process. The photocatalytic NO removal activity results show that the modification with Ag TNPs significantly boosted the removal performance up to 3.4 times higher than pristine SnO2. The underlying roles of Ag TNPs in NO removal activity improvement are due to some advantages of Ag TNPs. Moreover, the Ag TNPs contributed photogenerated holes as the main active species toward enhancing the NO oxidation reaction. In particular, the selectivity toward green products significantly improved from 52.78% (SnO2) to 86.99% (Ag TNPs/SnO2). The formation of reactive radicals under light irradiation was also verified by DMPO spin-trapping experiments. This work provides a potential candidate for visible-light photocatalytic NO removal with low toxic byproduct generation.

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Despite graphene being considered an ideal supercapacitor electrode material, its use in commercial devices is limited because few methods exist to produce high-quality graphene at a large scale and low cost. A simple method is reported to synthesize 3D graphene by graphenization of coal tar pitch with a K2CO3 catalyst. This produces 3D graphenes with high specific surface areas up to 2113 m2 g-1 and exceptional crystallinity (Raman ID/IG as low as ≈0.15). The material has an outstanding specific capacitance of 182.6 F g-1 at a current density of 1.0 A g-1. This occurs at a mass loading of 30 mg cm-2 which is 3 times higher than commercial requirements, yielding an ultra-high areal capacitance of 5.48 F cm-2. The K2CO3 is recycled and reused over 10 cycles with material quality and electrocapacitive performance of 3D graphene retained and verified after each cycle. The synthesis method and resulting electrocapacitive performance properties create new opportunities for using 3D graphene more broadly in practical supercapacitor devices.

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Carbon-based nanomaterials, such as carbon nanoplatelets, graphene oxide, and carbon quantum dots, have many possible end-use applications due to their ability to impart unique mechanical, electrical, thermal, and optical properties to cement composites. Despite this potential, these materials are rarely used in the construction industry due to high material costs and limited data on performance and durability. In this study, domestic coal is used to fabricate low-cost carbon nanomaterials that can be used economically in cement formulations. A range of chemical and physical processing approaches are employed to control the size, morphology, and chemical functionalization of the carbon nanomaterial, which improves its miscibility with cement formulations and its impact on mechanical properties and durability. At loadings of 0.01 to 0.07 wt.% of coal-derived carbon nanomaterial, the compressive and flexural strength of cement samples are enhanced by 24% and 23%, respectively, in comparison to neat cement. At loadings of 0.02 to 0.06 wt.%, the compressive and flexural strength of concrete composites increases by 28% and 21%, respectively, in comparison to neat samples. Additionally, the carbon nanomaterial additives studied in this work reduce cement porosity by 36%, permeability by 86%, and chloride penetration depth by 60%. These results illustrate that low-loadings of coal-derived carbon nanomaterial additives can improve the mechanical properties, durability, and corrosion resistance of cement composites.

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Memristors offer a crucial element for constructing discrete maps that have garnered significant attention in complex dynamics and various potential applications. In this study, we have integrated memristive and sigmoidal function to propose innovative mapping techniques. Our research confirms that the amalgamation of memristor and sigmoidal functions represents a promising approach for creating both 2D and 3D maps. Particularly noteworthy are the chaotic maps featuring multiple sigmoidal functions and multiple memristors, as highlighted in our findings. Specifically focusing on the novel STMM1 map, we delve into its dynamics and assess its feasibility. Intriguingly, the introduction of sigmoidal functions leads to alterations in the quantity of fixed points and the symmetry of the map.

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The recently uncovered two-dimensional materials serve as versatile building blocks for electronic devices. In this study, we methodically investigate the impact of substrate-induced strain and exchange field effects on the electronic density of states (EDOS) and electronic heat capacity (EHC) of single-layer ß12-borophene. Utilizing the Green's function approach, we compute these functions. The van Hove singularities in EDOS are observed to shift with strain, and depending on the direction and strength of the exchange field, the number of singularities increases. All these responses can be attributed to the renormalization of the velocity of electronic bands. Additionally, the inherent Schottky anomaly (an unusual peak at low temperatures) in the EHC undergoes a notable shift to higher and lower temperatures and variations in the intensity of the EHC due to substrate effects.

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According to a review of numerous publications and scientific reports, the effects of urbanization on urban climate are of greatest concern. This study aims to evaluate the impact of urbanization focusing on population growth on precipitation trends in 11 provinces across Vietnam during the period 2008-2018 by identifying the relationship between population growth and precipitation change. Regression analysis is used to determine the trends of precipitation and population growth. Precipitation maps and graphs show the overall precipitation trends, changes, and patterns in past decades. Overall, population growth tends to correlate with precipitation change trends. Furthermore, the type of region groups (countryside region, small city, or medium city) also plays a crucial role in determining the magnitude of the change in precipitation trends for each region. This further lends credibility to the notion that urbanization contributes to changes in precipitation trends.

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The development of hydrogen energy sources based on electrochemical water splitting is of increasing interest due to its advantages in energy and environmental fields. In this study, Co3O4 was decorated on carbon cloth (CC) by a hydrothermal method and was used as an electrode for water splitting. The structural and morphological properties of the materials are assessed using a range of reliable techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) with EDX mapping, and diffuse reflectance spectroscopy (DRS). Results indicate that the Co3O4/CC material was synthesized at 140 °C for 9 h and calcined at 350 °C achieving a superior overall water-splitting activity in the direction of hydrogen evolution reaction (HER) reaction than that of the oxygen evolution reaction (OER). In detail, HER characteristics with an overpotential at -0.234 V and a current density at 10 mA cm-2. In addition, the Co3O4/CC material also gives overpotential at 0.54 V for OER process. Furthermore, the electrochemical surface area of Co3O4/CC material is 7.6 times higher than CC electrode. Moreover, the CC fabric is destroyed when the annealing temperature is higher than 350 °C, leading to a significant decrease in the activity of Co3O4/CC. The as-prepared Co3O4 shows good adhesion and stability based on CC substrate without binder substance or further treatment of CC.

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This corrects the article on p. e88 in vol. 34, PMID: 37668081.

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Introduction: Piper lolot is a species of herb used as a popular food in Vietnam. Furthermore, the species has been used as a Vietnamese traditional medicine to treat many diseases. Methods: Chemical constituents in the essential oil from leaves of Piper lolot were determined using GC/MS analysis. The anti-gout and anti-diabetic activities of the essential oil were determined through the inhibitory assays against xanthine oxidase, α-glucosidase and α-amylase enzymes. In addition, molecular docking simulations were used to elucidate the inhibitory mechanism between the main compounds and the enzymes. Results: The dominant constituents of the Piper lolot essential oils were determined as ß-caryophyllene (20.6%), ß-bisabolene (11.6%), ß-selinene (8.4%), ß-elemene (7.7%), trans-muurola-4(14),5-diene (7.4%), and (E)-ß-ocimene (6.7%). The essential oil displayed xanthine oxidase, α-amylase, and α-glucosidase inhibitory activities with IC50 values of 28.4, 130.6, and 59.1 µg/mL, respectively. The anti-gout and anti-diabetic activities of the essential oil from the P. lolot species are reported for the first time. Furthermore, molecular docking simulation was consistent to in vitro experiments. Conclusion: The present study provides initial evidence that the essential oil of P. lolot may be a potential natural source to develop new diabetes preparations.

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Background: Personal protective equipment (PPE), an essential shield to protect healthcare workers (HCWs) during the COVID-19 pandemic, has been reported to affect their heart rate variability (HRV). Objective: To investigate the changes of very short-term heart rate variability in HCWs after three hours of wearing PPE to treat COVID-19 patients at different working times and intensities, and related factors. Methods: Sixty-five healthy HCWs were enrolled at the Number 2 Infectious Field Hospital (formed by Military Hospital 103), Vietnam. Two-minute 12-lead electrocardiograms were recorded before wearing and after removing PPE. Results: After three hours of wearing PPE, the mean heart rate of HCWs increased (p = 0.048) meanwhile, the oxygen saturation decreased significantly (p = 0.035). Standard deviation of all normal to normal intervals (SDNN), mean intervals RR (mean NN), and root mean square successive difference (rMSSD) after wearing PPE was also reduced significantly. SDNN, Mean NN, and rMSSD decreased as the working intensity increased (as in mild, moderate, and severe patient departments). In univariate regression analysis, logSDNN, logmean NN and logrMSSD were positively correlated with SpO2 and QT interval (r = 0.14, r = 0.31, r = 0.25; r = 0.39, r = 0.77, r = 0.73, respectively) and were negatively correlated with ambient temperature inside PPE (r = -0.41, r = -0.405, r = -0.25, respectively) while logmean NN and log rMSSD were negatively correlated with diastolic blood pressure (r = -0.43, r = -0.39, respectively). In multivariable regression analysis, logSDNN and logmean NN were negatively correlated to ambient temperature inside PPE (r = -0.34, r = -0.18, respectively). Conclusion: Time-domain heart rate variability decreased after wearing PPE. Time-domain HRV parameters were related to ambient temperature inside PPE, diastolic blood pressure, QT interval, and SpO2.

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The concentrations and profiles of 18 polycyclic aromatic hydrocarbons (PAHs) in particulate matter (PM10), fly ash (FA), and bottom ash (BA) were examined in three incineration residues. Samples were collected from different municipal and industrial solid waste incinerators in Northern Vietnam. The average concentrations of total PAHs in PM10, fly ash, and bottom ash were 9.55 × 103 ng/Nm3, 215 × 103 ng/g, and 2.38 ng/g, respectively. Low-molecular-weight PAHs (2 to 3 rings) were predominant in most samples. The emission factor of total PAHs decreased in the order of FA > BA > PM10. A higher concentration of total PAHs was found in industrial facilities than that in municipal ones. The high carcinogenic proportion of PAHs together with significantly high annual emissions reflect the high pollution risk to the ecosystem by PAHs in the case of reuse of incineration ashes (e.g., brick production). Regarding the carcinogenic risk of PAH-bounded ashes or particles, calculations from this study imply the significant threat for workers who have been manipulated in the incineration facilities, directly exposed to fly and bottom ashes. Meanwhile, the risk from PAH-bound particulate was not considered a significant threat for both normal adults and children. Further study on PAHs contained in incinerator waste dumps should be conducted in Vietnam to assess the potential contamination risk of these incineration by-products.

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In this study, we used Fe2O3/diatomite material system toward ciprofloxacin (CIP) photo-Fenton removal in water under visible light (vis) excitation. The characterization of Fe2O3/diatomite catalysts was determined by X-ray diffraction patterns, Fourier-transform infrared analysis, inductively coupled plasma mass spectrometry, and scanning electron microscopy. The photo-Fenton catalytic activity of the Fe2O3/diatomite was appraised by the removal efficiency of the CIP throughout the effect of the H2O2 with various parameters such as initial pH, catalyst amount, and H2O2 amount. The results indicate that 0.2 gL-1 Fe2O3/diatomite catalysts achieved the highest performance at approximately 90.03% with a 50 µL H2O2 concentration. Furthermore, the Fe2O3/diatomite catalysts have high stability, with over 80% CIP removed after five cycles. This study is inspired to develop a potential material for photo-Fenton degradation of antibiotics in wastewater.

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Mangrove forests provide vital ecosystem services. The increasing threats to mangrove forest extent and fragmentation can be monitored from space. Accurate spatially explicit quantification of key vegetation characteristics of mangroves, such as leaf area index (LAI), would further advance our monitoring efforts to assess ecosystem health and functioning. Here, we investigated the potential of radiative transfer models (RTM), combined with active learning (AL), to estimate LAI from Sentinel-2 spectral reflectance in the mangrove-dominated region of Ngoc Hien, Vietnam. We validated the retrieval of LAI estimates against in-situ measurements based on hemispherical photography and compared against red-edge NDVI and the Sentinel Application Platform (SNAP) biophysical processor. Our results highlight the performance of physics-based machine learning using Gaussian processes regression (GPR) in combination with AL for the estimation of mangrove LAI. Our AL-driven hybrid GPR model substantially outperformed SNAP (R2 = 0.77 and 0.44 respectively) as well as the red-edge NDVI approach. Comparing two canopy RTMs, the highest accuracy was achieved by PROSAIL (RMSE = 0.13 m2.m-2, NRMSE = 9.57%, MAE = 0.1 m2.m-2). The successful retrieval of mangrove LAI from Sentinel-2 can overcome extensive reliance on scarce in-situ measurements for training seen in other approaches and present a more scalable applicability by relying on the universal principles of physics in combination with uncertainty estimates. AL-based GPR models using RTM simulations allow us to adapt the genericity of RTMs to the peculiarities of distinct ecosystems such as mangrove forests with limited ancillary data. These findings bode potential for retrieving a wider range of vegetation variables to quantify large-scale mangrove ecosystem dynamics in space and time.

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A synergistic multilayer membrane design is necessary to satisfy a multitude of requirements of an ideal wound dressing. In this study, trilayer dressings with asymmetric wettability, composed of electrospun polycaprolactone (PCL) base membranes coated with oligomer chitosan (COS) in various concentrations of polyvinylpyrrolidone (PVP), are fabricated for wound dressing application. The membranes are expected to synergize the hygroscopic, antibacterial, hemostatic, and biocompatible properties of PCL and COS. The wound dressing was coated by spraying the solution of 3% COS and 6% PVP on the PCL base membrane (PVP6-3) three times, which shows good interaction with biological subjects, including bacterial strains and blood components. PVP6-3 samples confirm the diameter of inhibition zones of 20.0 ± 2.5 and 17.9 ± 2.5 mm against Pseudomonas aeruginosa and Staphylococcus aureus, respectively. The membrane induces hemostasis with a blood clotting index of 74% after 5 min of contact. In the mice model, wounds treated with PVP6-3 closed 95% of the area after 10 days. Histological study determines the progression of skin regeneration with the construction of granulation tissue, new vascular systems, and hair follicles. Furthermore, the newly-growth skin shares structural resemblances to that of native tissue. This study suggests a simple approach to a multi-purpose wound dressing for clinical treatment.