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By January 12, 2023, more than 84,500 mpox cases and 80 deaths had been reported from 110 countries because of an ongoing multicountry outbreak (1). Cases from Europe and Americas [...]

Organic thermally activated delayed fluorescence (TADF) materials have been widely investigated due to their impressive electronic properties and applied potential for the third generation of organic light-emitting diodes (OLED). We present organic TADF material (4BGIPN) based on the strained benzoguanidine donor and compare it with the benchmark carbazole-based material (4CzIPN). Extended π-conjugation in 4BGIPN material results in yellow-green luminescence at 512 nm with a fast radiative rate of 5.5 × 10−5 s−1 and a photoluminescence quantum yield of 46% in methylcyclohexane solution. Such a nitrogen-rich 4BGIPN material has a significantly stabilized highest occupied molecular orbital (HOMO) at −6.4 eV while the lowest unoccupied molecular orbital (LUMO) at −4.0 eV, indicating potential suitability for application as the electron transport layer or TADF class III emitter in OLEDs.

Abstract In this research, the photocatalytic degradation of CIP from aqueous solutions using CQD decorated on N-Cu co-doped titania (NCuTCQD) was made during two synthesis steps by sol–gel and hydrothermal methods. The fabricated catalysts were analyzed using various techniques, including XRD, FT-IR, BET, FESEM, EDX, and DRS. The results showed that N and Cu atoms were doped on TiO2 and CQD was well deposited on NCuT. The investigation of effective operational parameters demonstrated that the complete removal of ciprofloxacin (CIP: 20 mg/L) could be achieved at pH 7.0, NCuTCQD4wt%: 0.8 g/L, and light intensity: 100 mW/cm2 over 60 min reaction time. The O2 •– and OH˙ radicals were identified as the primary reactive species during the decontamination process. The synthesized photocatalyst could be recycled after six consecutive cycles of CIP decomposition with an insignificant decrease in performance. Pharmaceutical wastewater was treated through the optimum degradation conditions which showed the photocatalytic degradation eliminated 89% of COD and 75% of TOC within 180 min. In the effluent toxicity evaluation, the EC50 values for treated and untreated pharmaceutical wastewater increased from 62.50% to 140%, indicating that the NCuTCQD4wt%/Vis system can effectively reduce the toxic effects of pharmaceutical wastewater on aquatic environments.

Abstract Metronidazole (MNZ) is an extensively used antibiotic against bacterial infections for humans and farm animals. Prevention of antibiotics discharge is essential to prevent adverse environmental and health impacts. A member of metal–organic frameworks, zeolite imidazole framework-67 with cobalt sulfate precursor (ZIF-67-SO4) and exceptional physio-chemical properties was prepared via room temperature precipitation to adsorb MNZ. The study framework was designed by Box–Behnken Design to evaluate the effect of pH, ZIF-67-SO4 dose, and contact time on adsorption efficiency. The polynomial model fitted the adsorption system indicated the optimal condition for 97% MNZ removal occurs at pH = 7, adsorbent dosage = 1 g/L, and mixing time = 60 min. The model also revealed that the removal increased with contact time and decreased at strong pH. Equilibrium and kinetic study also indicated the adsorption of MNZ followed the intra-particle diffusion model and the Langmuir isotherm model with a qmax = 63.03 mg/g. The insignificant loss in removal efficacy in use-reuse adsorption cycles reflected the practical viability of ZIF-67-SO4.

Abstract Photocatalytic degradation under ultra-low powered light is a viable advanced oxidation process technique against extensive emerging contaminants. As a new and remarkable class of nanoporous materials, metal-organic frameworks (MOFs), attract interest for the supreme adsorptive and photocatalytic functionalities. An outstanding MOF, MIL-101(Fe) chosen as a photocatalyst template for the synthesis of α-Fe2O3 by a simple thermal modification to improve the structural properties toward methylene blue (MB) eradication. Octahedron-like α-Fe2O3 photocatalyst (Modified MIL-101(Fe), M-MIL-101(Fe)) was superior in dispersion and separation properties in aqueous medium. Moreover, the adsorptive and catalytic performance was increased for modified form by ~ 7.3% and ~ 17.1% compared to pristine MIL-101(Fe), respectively. Synergistic improvement of MB removal achieved by simultaneous adsorption/degradation under 5-W LED irradiation. Parametric study indicated an 18.1% and 44.5% improvement in MB removal was observed by increasing pH from 4 to 10, and M-MIL-101(Fe) dose from 0.2 to 1 g L−1, respectively. MB removal followed the pseudo-second-order kinetics model and the process efficiency dropped by 38% as MB concentration increased from 5 to 20 mg L−1. Radical trapping tests revealed the significant role of $${\mathrm{OH}}^{.}$$ OH . and electron radicals as the major participants in dye degradation. A significant loss in the efficiency of M-MIL-101(Fe) was observed in the reusability tests that is good to study further. In conclusion, a simple thermal post-synthesis modification on MIL-101(Fe) improved its structural, catalytic, and adsorptive properties against MB.

Recent studies for nanofluids, did not pay enough attention to the effect of the nanoparticle size and nanofluid stability on the heat transfer rate. In this study, the thermal conductivity (TC) coefficient of silica/deionized water (DW) nanofluid with various sizes of nanoparticles and various rates of nanofluid stability was investigated. Validation experiments, including X-Ray diffraction analysis (XRD), FE-Scanning Electron Microscopy (FE-SEM), Dynamic Light Scattering (DLS), and Zeta Potential (Zp), were carried out to examine the particle sizes and the nanofluid stability. The results illustrated that increasing the temperature leads to the augmentation of the TC coefficient of the SiO2/deionized water in all nanoparticle sizes and all volume concentrations. Also, increasing the volume concentration of the nanofluid leads to the augmentation of the TC coefficient of the nanofluid in all nanoparticle sizes and all temperatures. Eventually, increasing the nanoparticle sizes causes the TC coefficient of the nanofluid to be decreased in all volume concentrations. For the 11 nm nanoparticle size, the amount of the Relative TC (RTC) coefficient enhancement by increasing the temperature was 1.2%, 2.5%, 4.7%, and 6.8% for concentrations of 0.0.1%, 0.1%, 0.5%, and 1%, respectively. For the 50 nm nanoparticle size, this enhancement was from 0.7% to 6.5%, and for the 70 nm nanoparticle size, it was from 0.5% to 5.7%. Finally, Artificial Intelligence (AI) optimization was done to find the optimized size and stability.

Abstract In this study, a parametric analysis was conducted for the design of a suggested dual flapping hydrofoil turbine. A Navier–Stokes‐based computational fluid dynamics code was utilized for the analysis while varying the pitch angle, reduced frequency, separation distance, and phase difference. The smallest pitch angle of 60° and the reduced frequency of 0.1 among the given ranges of the parameters were fixed for the first parametric analysis. After an assessment, the 90° front‐lead with the longest distance of 6c and the 90° rear‐lead with the shortest distance of 2c were chosen for further parametric analysis based on a suggested performance indicator and a margin for improvement. It was derived from a subsequent parametric analysis that a 70° pitch angle, 0.12 reduced frequency, and a 4c distance for the 90° front‐lead was the final optimum with 59.48% efficiency and 55.44% fluctuation according to the performance indicator as well as the system length and power balance of dual hydrofoils.

The article's proposal refers to a new concept of wave energy converter (WEC), in which the power take-off (PTO) is combined with the mechanical and hydrostatic transmission. Here, the wave energy is absorbed by turning the two-way movement of an incident wave into the one-way rotation of a hydraulic pump which drives a high-pressure (HP) hydraulic circuit. Electricity is generated using a rotating generator which is driven by an HP hydraulic circuit. First, the coupled PTO mechanism is presented to describe the working principle of the proposed WEC. Next, a mathematical model of the buoy connects generator system is shown to analyze the equipment’s performance subjected regular waves. And then, by using the theory of linear potential wave, the hydrodynamic forces acting on the semi-submerged floating buoy and an analytical model of the mechanical transmission coupled with the hydraulic transmission are modeled to investigate the motion of the rotary generator. An experimental Setup is performed to verify the analytical model. Based on the validated model, a structural optimization is calculated to bring the system to resonance condition. Then, a dry test is implemented to analyze the system’s performance. Some optimum parameters are determined and applied to the analytical model, which sends the signal to drive the actuator. As a result, the absorbed efficiency is increased significantly.

This research analyzes the factors that affect resilience after natural disasters of 997 households in rural areas of Vietnam in 2008, 2010, 2012, 2014, and 2016 by using logistic regression. The research results show that factors such as receiving timely warnings related to natural disasters, not taking measures to respond to natural disasters, and putting trust in the community will improve resilience after natural disasters. If the household head is of Kinh ethnicity and participates in community organizations, the response capacity whenever a disaster occurs is higher, and vice versa. Additionally, household heads not responding to natural disasters, instead receiving support from their relatives and friends and borrowing capital positively affect resilience capacity after one year since the disaster. In cases where Kinh women are household heads and join social communities, the resilience capacity after one year also increases. Besides, the research suggests some solutions to develop resilience capacity, which focus on the relationship between characteristics of households, household heads, and disaster response with the resilience capacity of rural households in Vietnam. Finally, this research proposes some suitable policies to improve resilience capacity in Vietnamese rural areas.

BackgroundDuring acute myeloid leukemia (AML) growth, the bone marrow (BM) niche acquires significant vascular changes that can be offset by therapeutic blast cytoreduction. The molecular mechanisms of this vascular plasticity remain to be fully elucidated. Herein, we report on the changes that occur in the vascular compartment of the FLT3-ITD+ AML BM niche pre and post treatment and their impact on leukemic stem cells (LSCs).MethodsBM vasculature was evaluated in FLT3-ITD+ AML models (MllPTD/WT/Flt3ITD/ITD mouse and patient-derived xenograft) by 3D confocal imaging of long bones, calvarium vascular permeability assays, and flow cytometry analysis. Cytokine levels were measured by Luminex assay and miR-126 levels evaluated by Q-RT-PCR and miRNA staining. Wild-type (wt) and MllPTD/WT/Flt3ITD/ITD mice with endothelial cell (EC) miR-126 knockout or overexpression served as controls. The impact of treatment-induced BM vascular changes on LSC activity was evaluated by secondary transplantation of BM cells after administration of tyrosine kinase inhibitors (TKIs) to MllPTD/WT/Flt3ITD/ITD mice with/without either EC miR-126 KO or co-treatment with tumor necrosis factor alpha (TNFα) or anti-miR-126 miRisten.ResultsIn the normal BM niche, CD31+Sca-1high ECs lining arterioles have miR-126 levels higher than CD31+Sca-1low ECs lining sinusoids. We noted that during FLT3-ITD+ AML growth, the BM niche lost arterioles and gained sinusoids. These changes were mediated by TNFα, a cytokine produced by AML blasts, which induced EC miR-126 downregulation and caused depletion of CD31+Sca-1high ECs and gain in CD31+Sca-1low ECs. Loss of miR-126high ECs led to a decreased EC miR-126 supply to LSCs, which then entered the cell cycle and promoted leukemia growth. Accordingly, antileukemic treatment with TKI decreased the BM blast-produced TNFα and increased miR-126high ECs and the EC miR-126 supply to LSCs. High miR-126 levels safeguarded LSCs, as shown by more severe disease in secondary transplanted mice. Conversely, EC miR-126 deprivation via genetic or pharmacological EC miR-126 knock-down prevented treatment-induced BM miR-126high EC expansion and in turn LSC protection.ConclusionsTreatment-induced CD31+Sca-1high EC re-vascularization of the leukemic BM niche may represent a LSC extrinsic mechanism of treatment resistance that can be overcome with therapeutic EC miR-126 deprivation.