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In this study, rice husk biochar (RHB) and ZnO nanoparticles loaded rice husk biochar (RHB-ZnO-3 served to adsorb Reactive red 24 (RR24) in an aqueous solution. Effects of the ZnO nanoparticles loading ratio, solution pH, contact time, and initial RR24 concentration were evaluated utilizing detailed batch adsorption conditions. Isotherm and kinetic models helped to analyze the RR24 adsorption. Shown here is that the ratio of 3% (w/w) ZnO nanoparticles to RHB proved to be the best for fabricating highly effective modified rice husk biochar. In this scenario, the BET surface area of RHB-ZnO-3 was 13.84 m2/g, more than triple the original RHB (4.01 m2/g). Experimental results strongly suggest that RR24 highest adsorption capacities onto RHB-ZnO-3 and RHB were 174.91 mg/g and 88.51 mg/g, respectively. The best pH contact time and adsorbent rate for RR24 removal were 3, 60 min and 1.0 g/L, respectively. RR24 adsorption onto RHB and RHB-ZnO-3 were well described by Pseudo-second order kinetic and Langmuir isotherm models. Adsorption capacities of RHB and RHB-ZnO-3 did not diminish significantly after five cycles of adsorption-desorption. RHB and RHB-ZnO-3 could remove: firstly, more than half of the color and COD (50% color, 52.5% COD); and secondly, most of the turbidity (82.8%) from real textile wastewater. Electrostatic attraction, π-π interaction and pore filling were the main adsorption mechanisms of RR24 onto RHB and RHB-ZnO-3. • Right ratio of ZnO/rice husk biochar was identified for producing modified biochar. • Both RHB and RHB-ZnO coud remove RR24 effectively in wastewater. • RHB-ZnO adsorption capacity was much better than RHB due to ZnO on its surface. • Isotherm and kinetics RR24 adsorption were well fitted with Langmuir and PSO models. • Mechanisms included electrostatic attraction, pore filling, and π-π interaction. [ABSTRACT FROM AUTHOR]

The development of emission-tunable structures opens an optimistic future for white light-emitting diodes (WLED) utilizing a UV pump. Herein, we report emission-tunable Mn-doped ZnS/ZnO heterostructure nanobelts synthesized by the thermal evaporation method, following by an appropriate oxidation process. Under the UV excitation of 330 nm, the as-received nanobelts show an orange-yellow light with CCT of 3056 K, the 500 and 700 °C-oxidized samples strongly exhibit a warm white light emission with CCT of 3393 K and 3551 K, respectively. Surprisingly, the Mn-doped ZnS/ZnO heterostructures oxidized at 600 °C show a white light emission with CIE chromaticity coordinate of (0.31, 0.39) and CCT value of 6290 K, which are nearly very close to that of the commercial YAG:Ce3+ phosphor. A prototype WLED with the color coordinates of (0.33, 0.45), the CCT of 5491 K, and the QE ∼ 61% was successfully fabricated using Mn-doped ZnS/ZnO heterostructure nanobelts coated on the surface of UV (370 nm) chip. The obtained Mn-doped ZnS/ZnO heterostructures are promising to be applied in UV-pumped WLED fabrication. [Display omitted] • Mn-doped ZnS/ZnO heterostructure nanobelts have been synthesized by using a simple thermal evaporation and following by an oxidation process in the ambient. • The color temperature of the emission spectrum of Mn-doped ZnS/ZnO heterostructures could be tunable by oxidizing at different temperatures. • The Mn-doped ZnS/ZnO heterostructures oxidized at 600 °C for 30 min exhibits a white emission spectrum with a color temperature of 6290 K and the color coordinates (x, y) of (0.31, 0.39). • A prototype of UV-pump pc-WLED with the CCT of 5491 K, and high quantum efficiency of 61% was successfully fabricated. [ABSTRACT FROM AUTHOR]

In cell-based bone augmentation, transplanted cell dysfunction and apoptosis can occur due to oxidative stress caused by the overproduction of reactive oxygen species (ROS). Edaravone (EDA) is a potent free radical scavenger with potential medical applications. This study aimed to investigate the effect of controlling oxidative stress on bone regeneration using EDA. Bone marrow-derived cells were collected from 4-week-old rats, and EDA effects on cell viability and osteogenic differentiation were evaluated. Collagen gels containing PKH26-prelabeled cells were implanted into the calvarial defects of 12-week-old rats, followed by daily subcutaneous injections of normal saline or 500 μM EDA for 4 d. Bone formation was examined using micro-computed tomography and histological staining. Immunofluorescence staining was performed for markers of oxidative stress, macrophages, osteogenesis, and angiogenesis. EDA suppressed ROS production and hydrogen peroxide-induced apoptosis, recovering cell viability and osteoblast differentiation. EDA treatment in vivo increased new bone formation. EDA induced the transition of the macrophage population toward the M2 phenotype. The EDA group also exhibited stronger immunofluorescence for vascular endothelial growth factor and CD31. In addition, more PKH26-positive and PKH26-osteocalcin-double-positive cells were observed in the EDA group, indicating that transplanted cell survival was prolonged, and they differentiated into bone-forming cells. This could be attributed to oxidative stress suppression at the transplantation site by EDA. Collectively, local administration using EDA facilitates bone regeneration by improving the local environment and angiogenesis, prolonging survival, and enhancing the osteogenic capabilities of transplanted cells., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Background: Antimicrobial Stewardship Programs (ASP) have been applied widely in high-resource countries to prevent surgical site infections (SSI). Evidence favoring ASP interventions (ASPi) in gastrointestinal surgeries from low and middle-income countries has been limited, especially in antimicrobial prophylaxis. We aimed to investigate this gap at a Vietnamese tertiary hospital., Methods: We conducted a retrospective cohort study on patients undergoing clean-contaminated surgeries in 2015 who received standard of care (SoC) or SoC + ASPi. Primary outcome was 30-day SSI incidence. Secondary outcomes included length of stay (LoS) after surgery (days), cost of antibiotics, and cost of treatment (USD). Results were controlled for multiplicity and reported with treatment effect and 95% confidence interval (95%CI). A predictive model was built and cross-validated to detect patients at high risk of SSI., Results: We included 395 patients for analysis (48.1% being female, mean age 49.4 years). Compared to patients receiving SoC, those with SoC + ASPi had a lower incidence of 30-day SSI (-8.8, 95%CI: -16.0 to -1.6, p  = 0.042), shorter LoS after surgery (-1.1 days, 95%CI: -1.8 to -0.4, p  = 0.004), and lower cost of antibiotics (-37.3 USD, 95%CI: -59.8 to -14.8, p  = 0.012) and treatment (-191.1 USD, 95%CI: -348.4 to -33.8, p  = 0.042). We estimated that by detecting patients at high risk of SSI with the predictive model and providing prophylactic measures, we could save 398120.7 USD per 1,000 cases of SSI., Conclusion: We found that ASPi were associated with a reduction in risks of SSI, hospital stays, and cost of antibiotics/treatment in a Vietnamese tertiary hospital., Competing Interests: HTP and M-HT reported receiving grants from Nguyen Tat Thanh University outside the submitted work. HTP reported receiving grants from Servier Vietnam Ltd. outside the submitted work. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Pham, Mai-Phan, Nguyen, Nguyen and Tran.)

The thermoelectric performance of SnSe strongly depends on its low-energy electron band structure that provides high density of states in a narrow energy window due to the multi-valley valence band maximum (VBM). Angle-resolved photoemission spectroscopy measurements, in conjunction with first-principles calculations, reveal that the binding energy of the VBM of SnSe is tuned by the population of Sn vacancy, which is determined by the cooling rate during the sample growth. The VBM shift follows precisely the behavior of the thermoelectric power factor, while the effective mass is barely modified upon changing the population of Sn vacancies. These findings indicate that the low-energy electron band structure is closely correlated with the high thermoelectric performance of hole-doped SnSe, providing a viable route toward engineering the intrinsic defect-induced thermoelectric performance via the sample growth condition without an additional ex-situ process., (© 2023. The Author(s).)

It is essential to achieve herd immunity in order to control the COVID-19 pandemic, and this requires a high level of vaccination rate. Despite the importance of vaccination, hesitancy and unwillingness in receiving the COVID-19 vaccine still exists. It is therefore crucial to comprehend the intentions of adults regarding COVID-19 vaccination, which is beneficial for establishing community immunity and an efficient future pandemic response. An online survey was administered to 2722 adults in Vietnam. Cronbach's alpha, exploratory factor analysis (EFA), and confirmatory factor analysis (CFA) were used to test the reliability and validity of the developed scales. Then, structural equational modeling (SEM) was employed to test correlations. This study found that favorable attitudes toward COVID-19 vaccines played the most important role in shaping adults' intention to receive these vaccines, followed by perceived behavioral control, perceived benefits of COVID-19 vaccines, and subjective norms. Concurrently, all three core dimensions of the theory of planned behavior mediated the link between the perceived benefits of COVID-19 vaccines and the intention to receive them. Also, there were significant differences between males and females in the way they formed this intention. The findings of this study offer valuable guidance for practitioners on how to encourage adults to receive COVID-19 vaccinations, as well as how to limit the transmission of the COVID-19 virus., Competing Interests: The authors declare no conflict of interest.The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

The construction of a Z-scheme photocatalyst by coupling semiconductors with conductors is an efficient way to achieve high pollutant degradation efficiency. In this study, a hydrothermal approach was used to fabricate a Z-scheme photocatalyst consisting of C-MoS 2 sheets wrapped around octahedral anatase TiO 2 nanocrystals. The catalyst showed excellent photocatalytic efficiency (99%) for methylene blue degradation with low catalyst loading (0.2 g L -1 ) under the simulated solar light within 60 min. High photocatalytic degradation efficiencies were also observed for Rhodamine B, methyl orange, and tetracycline under solar irradiation. The C-MoS 2 acts as an electron mediator and serves as a carrier transmission bridge for the efficient electron-hole separation. The electron-rich (101)-faceted TiO 2 benefits the Z-scheme recombination of electrons from the conduction band of TiO 2 and holes at the valence band of MoS 2 . The semiconductor coupling of (101)-exposed octahedral TiO 2 and 2H-MoS 2 as well as the introduction of solid-state electron mediators, 1T-MoS 2 and carbon, resulted in increased light absorption and accelerated charge transfer at the contact interface, which enhanced the photocatalytic activity of the photocatalyst significantly compared to those of P25, MoS 2 /TiO 2 , and C-MoS 2 . The efficient separation of electron-hole pairs prolongs their lifetime for oxidation and reduction reactions in the degradation process., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)