Significant Degradation Research Articles

Influence of ozone supply mode and aeration on photocatalytic ozonation of organic pollutants in wastewater using TiO2 and ZnO nanoparticles

Photocatalytic ozonation, which combines the effects of lighting and ozonation, has been shown to enhance the decolorization and degradation of organic pollutants in wastewater. Dye solutions with concentrations of 10 ppm for both methylene blue and methyl orange dyes were used. The influence of ozoneation on the performance of photocatalytic activity of TiO2 and ZnO nanoparticles for the removal of organic dyes from aqueous solutions was investigated. To evaluate their efficacy for the removal of methylene blue and methyl orange dyes from aqueous solutions, the photocatalysts were exposed to UV light for 90 min, with ozone supplied either intermittently or continuously by an SDBD cold plasma reactor. The photocatalysts utilized in this study were characterized using SEM and XRD techniques. The degree of color degradation was determined using UV–Vis spectroscopy. The results demonstrate that TiO2 and ZnO nanoparticles exhibit different degrees of photocatalytic activity for the two dyes. The addition of ozone was found to enhance both the color degradation and mineralization rates of the pollutants, with intermittent ozonation proving more effective than continuous ozonation. The most significant color degradation results were obtained using TiO2 nanoparticles with intermittent ozonation for methylene blue dye (97 %) and ZnO nanoparticles with intermittent ozonation for methyl orange dye (40 %). Overall, this study provides evidence that photocatalytic ozonation represents a promising technique for water treatment.

A Light-Weighted Machine Learning Approach to Channel Estimation for New-Radio Systems

In this paper, we provide a light-weighted Machine Learning (ML) approach to channel estimation for New-Radio (NR) systems. Specifically, based on the equivalence between the Channel Impulse Response (CIR) in the time domain and its corresponding Channel Frequency Response (CFR) in the frequency domain, the light-weighted ML model for the channel estimation is shown to be established in comparison to the existing ML-based channel estimator. Furthermore, for practical use, the quantized weights for the light-weighted ML-based estimator are shown to be feasible without significant performance degradation in the sense of mean square error (MSE), which shows the effectiveness of the proposed approach from the perspective of memory overhead. Consequently, we show that there exists Signal to Noise Ratio (SNR) gain in comparison with the existing ML-based estimator, which is validated by numerical results considering the Sounding Reference Signal (SRS) for NR in the 3rd Generation Partnership Project (3GPP).

RuO2@IrO2/C Core-Shell Structure Catalyst for Efficient and Durable Acidic Oxygen Evolution

Proton exchange membrane (PEM) water electrolysis for hydrogen production has a high current density and overall efficiency, and is a very promising hydrogen production strategy. However, its application is limited by the high anodic overpotential for oxygen evolution and the instability of catalysts. Therefore, anodic catalysts with a high activity and durability under acidic conditions need further research. Herein, we first synthesized the key intermediate Ru@Ir core-shell structures by controlling nanocrystals, then loaded them onto a carbon support and calcined to obtain a RuO2@IrO2/C core-shell nanocatalyst with a size smaller than 5 nm, whose activity exceeded that of commercial RuO2 and commercial IrO2. After a 200 h stability test, the catalyst did not show significant performance degradation or structural degeneration. Finally, the prepared catalyst was assembled into a PEM electrolyzer showing the same results as the three-electrode tests, demonstrating its potential for practical applications and providing new insights for designing nanocatalysts suitable for industrialized PEM water electrolysis to produce hydrogen

Rice husk–based pyrogenic carbonaceous material efficiently promoted peroxymonosulfate activation toward the non-radical pathway for the degradation of pharmaceuticals in water

Pristine pyrogenic carbonaceous material (BRH) obtained from rice husk and modified with FeCl3 (BRH-FeCl3) were prepared and explored as carbocatalysts for the activation of peroxymonosulfate (PMS) to degrade a model pharmaceutical (acetaminophen, ACE) in water. The BRH-FeCl3/PMS system removed the pharmaceutical faster than the BRH/PMS. This is explained because in BRH-FeCl3, compared to BRH, the modification (iron played a role as a structuring agent mainly) increased the average pore diameter and the presence of functional groups such as -COO−, -Si–O−, or oxygen vacancies, which allowed to remove the pollutant through an adsorption process and significant carbocatalytic degradation. BRH-FeCl3 was reusable during four cycles and had a higher efficiency for activating PMS than another inorganic peroxide (peroxydisulfate, PDS). The effects of BRH-FeCl3 and PMS concentrations were evaluated and optimized through an experimental design, maximizing the ACE degradation. In the optimized system, a non-radical pathway (i.e., the action of singlet oxygen, from the interaction of PMS with defects and/or -COO−/-Si–O− moieties on the BRH-FeCl3) was found. The BRH-FeCl3/PMS system generated only one primary degradation product that was more susceptible to biodegradation and less active against living organisms than ACE. Also, the BRH-FeCl3/PMS system induced partial removals of chemical oxygen demand and dissolved organic carbon. Furthermore, the carbocatalytic system eliminated ACE in a wide pH range and in simulated urine, having a low-moderate electric energy consumption, indicating the feasibility of the carbocatalytic process to treat water polluted with pharmaceuticals.

Reconstruction of degraded image transmitting through ocean turbulence via deep learning

When a laser carrying image information is transmitted in seawater, the presence of ocean turbulence leads to significant degradation of the received information due to the effect of interference. To address this issue, we propose a deep-learning-based method to retrieve the original information from a degraded pattern. To simulate the propagation of laser beams in ocean turbulence, a model of an ocean turbulence phase screen based on the power spectrum inversion method is used. The degraded images with different turbulence conditions are produced based on the model. A Pix2Pix network architecture is built to acquire the original image information. The results indicate that the network can realize high-fidelity image recovery under various turbulence conditions based on the degraded patterns. However, as turbulence strength and transmission distance increase, the reconstruction accuracy of the Pix2Pix network decreases. To further improve the image reconstruction ability of neural network architectures, we established three networks (U-Net, Pix2Pix, and Deep-Pix2Pix) and compared their performance in retrieving the degraded patterns. Overall, the Pix2Pix network showed the best performance for image reconstruction.

Mango peel as a potential enzyme inducer in Trichoderma harzianum

Water-insoluble exopolysaccharides (I-EPS) are a virulence factor for dental biofilms. It has already been demonstrated that mango pulp induces the secretion of glucan-hydrolytic enzymes in the fungus Trichoderma harzianum, and that they have an effect on I-EPS from young biofilms. Aim: Evaluate the effect of mango peel as an enzyme inducer in T. harzianum, and the effect of enzymes secreted on mature biofilms. Methods: Fractions of the peel (PL) and ethanol-precipitated pulp (PP) of Tommy Atkins mangoes were sterilized and added to a culture medium containing T. harzianum for induction of hydrolytic enzymes. After 192 h, the culture medium was centrifuged and the supernatant (enzyme extract) was used as treatment on S. mutans biofilms (n=9): a) NaCl 0.9 %; b) 0.12 % chlorhexidine digluconate; and c) extract of enzymes induced by PL or PP. Acidogenicity, bacterial viability, quantification of insoluble polysaccharides, and three-dimensional analysis of the biofilm by scanning electron microscopy (SEM) was performed. Data were analyzed by ANOVA followed by the Tukey test (α=5 %). Results: The hydrolytic enzymes did not alter the metabolism or bacterial viability of the biofilm (p<0.05). Although the images obtained by SEM suggest some degree of matrix degradation, the quantification of I-EPS for the PL and PP groups did not differ from the control group (p>0.05), suggesting a slight effect on the disorganization of the mature S. mutans biofilm. Conclusion: The results suggest that mango peel fraction can induce secretion of mutanase by T. harzianum, however in an insufficient amount to generate significant degradation on cariogenic biofilm.

Optimization of Green Vehicle Paths Considering the Impact of Carbon Emissions: A Case Study of Municipal Solid Waste Collection and Transportation

In recent years, the waste produced as a result of the production and consumption activities of urban residents has led to significant environmental degradation and resource wastage. This paper focuses on the research object of municipal solid waste (MSW) collection and transportation based on the concept of “sustainable development and green economy”. Firstly, this study examines the current state of urban domestic garbage collection and transportation. It analyzes the following challenges and deficiencies of the existing collection and transportation system: (1) the operating efficiency of garbage collection vehicles is low, resulting in a significant accumulation of waste on the roadside and within the community; (2) the vehicle collection and transportation routes are fixed, and there are empty vehicles running; (3) the amount of garbage on a route exceeds the vehicle’s loading capacity, which requires the vehicle to perform a second round of collection and transportation. To enhance the efficiency of urban garbage collection and transportation and minimize the collection and transportation costs, we are investigating the problem of optimizing the path for green vehicles. To comprehensively optimize the fixed cost, variable cost, and carbon emission cost incurred during vehicle operation, a vehicle routing model with time windows is established, taking into account vehicle load constraints. Carbon emission coefficient and carbon tax parameters are introduced into the model and the “fuel-carbon emission” conversion method is used to measure the carbon cost of enterprises. An improved ant colony optimization (ACO) method is proposed: (1) the introduction of a vehicle load factor improves the ant state transfer method; (2) the updated pheromone method is improved, and additional pheromone is added to both the feasible path and the path with the minimum objective function; (3) the max–min ACO algorithm is introduced to address the issue of premature convergence of the algorithm; (4) the embedding of a 2-opt algorithm further prevents the ACO algorithm from falling into the local optimum. Finally, the calculation results based on the example data demonstrate that the algorithm has a significant advantage over the genetic algorithm (GA) and particle swarm optimization (PSO) algorithm. The total transportation distance determined by this algorithm is shorter than that of the GA and PSO methods, and the total cost of the scheme is 1.66% and 1.89% lower than that determined by GA and PSO, respectively. Compared to the data from the actual case, the number of vehicles required in the operation of this algorithm and model is reduced by three. Additionally, the total cost, fixed cost, and carbon emission cost incurred by the vehicles during operation were reduced by 31.2%, 60%, and 25.3% respectively. The results of this study help the station to collect and distribute waste efficiently, while also achieving the goals of energy saving, consumption reduction, and emission reduction.

Livestock movement driven phosphorus transitions as core drivers of grassland vegetation dynamics

The Banni grasslands, located in the Kachchh district of India, have experienced significant degradation and a decrease in grassland productivity. Phosphorus is a crucial nutrient for grassland productivity, and its availability is often limited in these ecosystems. The study is a maiden attempt to understand the link between phosphorus availability, measured by the phosphorus activation coefficient (PAC), phosphate solubilizing microorganisms (PSM), vegetation patterns, indicated by normalized difference vegetation index (NDVI) and its relationship with livestock movement. Soil samples were collected from 45 locations spread across the three divisions of Banni grassland, and various soil parameters including phosphorus content, organic carbon, and microbial activity were analyzed. The results showed that the concentration of available phosphorus (AP) varied significantly among different divisions of the grassland, with division 1 having the highest AP concentration. The phosphorus activation coefficient (PAC) was also highest in division 2. Additionally, PSM diversity was significantly different among divisions, with division 2 exhibiting the highest PSM values. The NDVI values, representing vegetation density, varied across divisions, with division 1 having the highest overall NDVI. Statistical analysis revealed significant positive correlations between PAC, PSM, and NDVI. The research emphasizes the significance of PSM driven phosphorus availability in influencing vegetation dynamics within the Banni grassland ecosystem. The movement of livestock emerges as a key factor in introducing organic matter and phosphate solubilizing microorganisms, thereby facilitating the conversion of total phosphorus (TP) into forms accessible to plants. The study indicates that implementing effective phosphorus management practices, taking into account livestock movement and organic contributions, could enhance grassland productivity and ensure the long-term sustainability of the ecosystem. These findings offer valuable insights for more holistic and nuanced understanding of the complex relationships between phosphorus availability, phosphate solubilizing microorganisms, vegetation patterns, and sustainable management in the Banni grasslands and potentially in other ecosystems facing similar challenges.

Preparation of carboxy sulfonic acid‐containing copolymer scale inhibitors and their scale inhibition effect on CaCO3

AbstractFree radical polymerization was selected to obtain a promising copolymer scale inhibitor IA‐AM‐SAS with good water solubility and temperature and salt resistance, which is suitable for the treatment of surface pipeline water in oil fields, using itaconic acid (IA), acrylamide (AM), and sodium acrylsulfonate (SAS) as the monomers. The structure of the synthesized copolymer was verified by Fourier transform infrared spectroscopy and nuclear magnetic resonance hydrogen spectroscopy. Thermogravimetric results showed that the copolymer does not undergo significant thermal degradation at temperatures below 356°C, indicating that the copolymer has good thermal stability. The molecular weights of the polymers at different monomer ratios were measured using gel permeation chromatography and the relationship between the molecular weights and scale inhibition performance was discussed. The results showed that the scale inhibition effect was best when the monomer molar ratio n(IA): n(AM): n(SAS) was 0.5:2:1.5 and the number of average molecular weight of the prepared copolymer was 7712 g/mol, and the inhibition efficiency of CaCO3 was 84.02% when IA‐AM‐SAS was at a concentration of 30 mg L−1, and the inhibition rate was measured by the standard of static scale inhibition test in the oilfield measured. The range of conditions (PH, Ca2+ concentration, water temperature, and time) of the static scale inhibition test was then expanded using a one‐way controlled variable experiment to explore the performance of IA‐AM‐SAS scale inhibitors under different water quality conditions. The scale inhibition mechanism was explored by scanning electron microscopy, x‐ray diffraction, and x‐ray photoelectron spectroscopy. Briefly, the combination of multiple functional groups enables IA‐AM‐SAS to be applied in complex and challenging environments.

Ethnobotanical study of traditional forage plants in the Gansu–Ningxia–Inner Mongolia junction zone: conservation and sustainable utilization for animal husbandry

IntroductionThis study aims to safeguard the ethnobotanical knowledge pertaining to traditional forage plants within the ethnically diverse Gansu–Ningxia–Inner Mongolia junction zone. It seeks to establish a foundation for the sustainable utilization of these traditional resources for animal husbandry.MethodsA combination of literature research, village interviews, participatory observation, and ethnobotanical quantitative evaluation methods was employed to investigate and study the traditional knowledge of wild forage plants used by local residents in the study area.ResultsLocal residents provided information on 73 forage plants, which were identified as 116 distinct wild forage plant species. These plants belong to 22 families and play an active role in the lives of the local inhabitants. Notably, the families Poaceae, Fabaceae, and Asteraceae are prominent, comprising the most abundant and widely utilized wild forage plants. Bing Cao (collectively referring to plants of the Agropyron, Leymus, and Psammochloa), Suo Cao (collectively referring to plants of the genus Stipa), and Ku Cai (encompassing Lactuca tatarica (L.) C.A.Mey. and Ixeris polycephala Cass.) emerge as the most representative and vital wild forage plants for animal husbandry. Additionally, plants within the Astragalus (referred to collectively as NiaoZi by local residents) in the Fabaceae family, as well as plants from the Amaranthaceae family, exhibit notable significance.ConclusionAnimal husbandry assumes a pivotal role in the local agricultural economy, and the 116 wild forage plants investigated hold substantial importance in its development. Among these, 59 and 103 plant resources display high developmental potential, making them prospective candidates for high-quality cultivated forage grasses. Additionally, extensive grazing practices have resulted in significant ecological degradation within this already fragile ecosystem. The cultivation of forage grasses and the practice of pen-based animal husbandry may emerge as crucial strategies for sustainable development in this area.

Deep Transfer Learning for Ethnically Distinct Populations: Prediction of Refractive Error Using Optical Coherence Tomography.

The mismatch between training and testing data distribution causes significant degradation in the deep learning model performance in multi-ethnic scenarios. To reduce the performance differences between ethnic groups and image domains, we built a deep transfer learning model with adaptation training to predict uncorrected refractive errors using posterior segment optical coherence tomography (OCT) images of the macula and optic nerve. Observational, cross-sectional, multicenter study design. We pre-trained a deep learning model on OCT images from the B&VIIT Eye Center (Seoul, South Korea) (N = 2602 eyes of 1301 patients). OCT images from Poona Eye Care (Pune, India) were chronologically sorted into adaptation training data (N = 60 eyes of 30 patients) for transfer learning and test data (N = 142 eyes of 71 patients) for validation. Deep learning models were trained to predict spherical equivalent (SE) and mean keratometry (K) values via transfer learning for domain adaptation. Both adaptation models for SE and K were significantly better than those without adaptation (P < 0.001). In myopia/hyperopia classification, the model trained on circular optic disc OCT images yielded the best performance (accuracy = 74.7%). It also performed best in estimating SE with the lowest mean absolute error (MAE) of 1.58 D. For classifying the degree of corneal curvature, the optic nerve vertical algorithm performed best (accuracy = 65.7%). The optic nerve horizontal model achieved the lowest MAE (1.85 D) when predicting the Kvalue. Saliency maps frequently highlighted the retinal nerve fiber layers. Adaptation training via transfer learning is an effective technique for estimating refractive errors and K values using macular and optic nerve OCT images from ethnically heterogeneous populations. Further studies with larger sample sizes and various data sources are needed to confirm the feasibility of the proposed algorithm.

Engineering alginate/carboxymethylcellulose scaffolds to establish liver cancer spheroids: Evaluation of molecular variances between 2D and 3D models

Natural polymeric hydrogels represent an optimal framework for 3D culture development. This study demonstrates a freeze-thaw-based ionic crosslinking technique for fabricating alginate/carboxymethylcellulose scaffold for culturing human hepatocellular carcinoma, Huh-7 cells to generate 3D spheroids. Consolidating morphological and biomechanical characterization of Alg/CMC scaffolds shows the formation of uniform hydrogels with significant crosslinking (ATR-FTIR), multiscale pores (FE-SEM), swelling/water absorbance, softer texture, viscoelasticity (rheology), spreading nature (contact angle), and degradation rate optimal for 3D culture establishment. The influence of cell seeding density and time with spheroid formation reveals a maximal size of 250–300 μm on day 7. Calcein AM and Propidium iodide staining confirm that a culmination of viable and dead cells generates spheroidal heterogeneity. RT-qPCR in 3D culture against RPL-13 and 2D culture controls indicate an upregulation of E-cadherin, N-cadherin, fibronectin, and integrin α9/β6. Further, western blotting and immunofluorescence confirm the collective display of cellular interactions in 3D spheroids. Thus, the expression profile signifies the role of key genes during the assembly and formation of 3D spheroids in 1%Alg/1%CMC scaffolds with a profound epithelial characteristic. In the future, this study will bring a 3D spheroid model in a platter for elucidating epithelial to mesenchymal transition of cells during in vitro disease modeling.

The remediation of marine sediments containing polycyclic aromatic hydrocarbons by peroxymonosulfate activated with Sphagnum moss-derived biochar and its benthic microbial ecology

This research was to study the efficiency of Sphagnum moss-derived biochar (SMBC) in removing polycyclic aromatic hydrocarbons (PAHs) from marine sediment using a peroxymonosulfate (PMS)-based carbon-advanced oxidation process (PMS-CAOPs). Sphagnum moss-derived biochar (SMBC) was generated via a simple thermochemical process for PMS activation toward enhancing decontamination of sediments. At pH 6, the SMBC/PMS system achieved a PAH removal efficiency exceeding 78% in 12 h reaction time. Moreover, PAHs of 6-, 5-, 4-, 3-, and 2-ring structures exhibited 98%, 74%, 68%, 85%, and 91%, of removal, respectively. The SMBC activation of PMS generated both radicals (SO4•– and HO•) and nonradical (1O2), species responsible for PAHs degradation, attributed primarily to inherent iron and carbon moieties. The significant PAHs degradation efficiency showcased by the SMBC/PMS process holds promise for augmenting the performance of indigenous benthic microbial activity in sediment treatment contexts. The response of sediment microbial communities to PAH-induced stress was particularly associated with the Proteobacteria phylum, specifically the Sulfurovum genus. The findings of the present study highlight the efficacy of environmentally benign reactive radical/nonradical-based PMS-CAOP using pristine carbon materials, offering a sustainable strategy for sediment treatment.

Key trends in the response of suction bucket foundations to extreme axial cyclic loads

The offshore wind industry is currently expanding into emerging markets at a rapid pace. Some of these markets are located in areas characterized by frequent extreme events. From a geotechnical perspective, this results in new design challenges, as foundations must withstand severe loads repeatedly throughout their intended lifetimes. Jacket structures resting on suction buckets represent a new foundation concept that still requires research to become a potential optimal solution. The vertical cyclic response of bucket foundations constitutes the main topic of this article. The current study is based on observations of the behavior of a scaled model installed in dense sand. Both normal and extreme conditions were simulated by applying axial cyclic loads of varying amplitudes, means, and frequencies. High amplitude and low frequency cause significant stiffness degradation and permanent displacement. These scenarios occur due to build-up of excess pore pressure, with subsequent triggering of liquefaction. A criterion for liquefaction occurrence is identified and may be readily used for practical applications. Considerable levels of tensile loading lead to a high rate of heave, regardless of frequency. For one-way compressive forces, after an extreme loading sequence, stiffness returns to its initial level, as long as no liquefaction develops priorly. This bears essential implications in predicting the change of natural frequency of the system.

Electrooxidation of chlorophene and dichlorophen by reactive electrochemical membrane: Key determining factors of removal efficiency

This study systematically investigated the variable main electrooxidation mechanism of chlorophene (CP) and dichlorophen (DCP) with the change of reaction conditions at Ti4O7 anode operated in batch and reactive electrochemical membrane (REM) modes. Significant degradation of CP and DCP was observed, that is, CP exhibited greater removal efficiency in batch mode at 0.5–3.5 mA cm−2 and REM operation (0.5 mA cm−2) with a permeate flow rate of 0.85 cm min−1 under the same reaction conditions, while DCP exhibited a faster degradation rate with the increase of current density in REM operation. Density functional theory (DFT) simulation and electrochemical performance tests indicated that the electrooxidation efficiency of CP and DCP in batch mode was primarily affected by the mass transfer rates. And the removal efficiency when anodic potentials were less than 1.7 V vs SHE in REM operation was determined by the activation energy for direct electron transfer (DET) reaction, however, the adsorption function of CP and DCP on the Ti4O7 anode became a dominant factor in determining the degradation efficiency with the further increase of anodic potential due to the disappeared activation barrier. In addition, the degradation pathways of CP and DCP were proposed according to intermediate products identification and frontier electron densities (FEDs) calculation, the acute toxicity of CP and DCP were also effectively decreased during both batch and REM operations.

Green Synthesis of Copper Oxide Nanoparticles from the Leaves of Aegle marmelos and Their Antimicrobial Activity and Photocatalytic Activities.

The leaves of the Aegle marmelos plant were used for the green synthesis of copper oxide nanoparticles and further characterized by different techniques, including (Ultra Violet-Visible) UV-Vis, Scanning electron microscopy (SEM), Energy dispersive X-ray (EDX), Transmission electron microscopy (TEM) and X-ray diffraction (XRD). The UV-Vis showed a peak at 330 nm, which may be due to the Surface Plasmon Resonance phenomenon. XRD analysis showed the crystalline nature of copper oxide nanoparticles (CuO NPs). In contrast, SEM showed that nanoparticles were not aggregated or clumped, EDX showed the presence of elemental copper., and further, the TEM analysis revealed the average particle size of copper oxide nanoparticles to be 32 nm. The Minimum Inhibitory Concentration (MIC) for Escherichia coli (E. coli) and Staphylococcusaureus (S. aureus) was found to be 400 µg/mL, whereas for Candida albicans (C. albicans) and Candida dubliniensis (C. dubliniensis) it was 800 µg/mL. The zone of inhibition in the well diffusion assay showed the antimicrobial activity of copper oxide nanoparticles, and it also showed that as the concentration of copper oxide nanoparticles increased, the zone of inhibition also increased. Further, the electron microscopic view of the interaction between copper oxide nanoparticles and C. albicans cells showed that CuO NPs were internalized and attached to the cell membrane, which caused changes in the cellular structure and caused deformities which eventually led to cell death. The prepared CuO NPs showed significant photocatalytic degradation of organic dyes in the presence of sunlight.

Expanding the Potential of Self-Assembled Silk Fibroin as Aerogel Particles for Tissue Regeneration.

A newly produced silk fibroin (SF) aerogel particulate system using a supercritical carbon dioxide (scCO2)-assisted drying technology is herein proposed for biomedical applications. Different concentrations of silk fibroin (3%, 5%, and 7% (w/v)) were explored to investigate the potential of this technology to produce size- and porosity-controlled particles. Laser diffraction, helium pycnometry, nitrogen adsorption-desorption analysis and Fourier Transform Infrared with Attenuated Total Reflectance (FTIR-ATR) spectroscopy were performed to characterize the physicochemical properties of the material. The enzymatic degradation profile of the SF aerogel particles was evaluated by immersion in protease XIV solution, and the biological properties by cell viability and cell proliferation assays. The obtained aerogel particles were mesoporous with high and concentration dependent specific surface area (203-326 m2/g). They displayed significant antioxidant activity and sustained degradation in the presence of protease XIV enzyme. The in vitro assessment using human dermal fibroblasts (HDF) confirm the particles' biocompatibility, as well as the enhancement in cell viability and proliferation.

The Leptospermum scoparium (Mānuka)-Specific Nectar and Honey Compound 3,6,7-Trimethyllumazine (LepteridineTM) That Inhibits Matrix Metalloproteinase 9 (MMP-9) Activity.

3,6,7-trimethyllumazine (Lepteridine™) is a newly discovered natural pteridine derivative unique to Mānuka (Leptospermum scoparium) nectar and honey, with no previously reported biological activity. Pteridine derivative-based medicines, such as methotrexate, are used to treat auto-immune and inflammatory diseases, and Mānuka honey reportedly possesses anti-inflammatory properties and is used topically as a wound dressing. MMP-9 is a potential candidate protein target as it is upregulated in recalcitrant wounds and intestinal inflammation. Using gelatin zymography, 40 μg/mL LepteridineTM inhibited the gelatinase activities of both pro- (22%, p < 0.0001) and activated (59%, p < 0.01) MMP-9 forms. By comparison, LepteridineTM exerted modest (~10%) inhibition against a chromogenic peptide substrate and no effect against a fluorogenic peptide substrate. These findings suggest that LepteridineTM may not interact within the catalytic domain of MMP-9 and exerts a negligible effect on the active site hydrolysis of small soluble peptide substrates. Instead, the findings implicate fibronectin II domain interactions by LepteridineTM which impair gelatinase activity, possibly through perturbed tethering of MMP-9 to the gelatin matrix. Molecular modelling analyses were equivocal over interactions at the S1' pocket versus the fibronectin II domain, while molecular dynamic calculations indicated rapid exchange kinetics. No significant degradation of synthetic or natural LepteridineTM in Mānuka honey occurred during simulated gastrointestinal digestion. MMP-9 regulates skin and gastrointestinal inflammatory responses and extracellular matrix remodelling. These results potentially implicate LepteridineTM bioactivity in Mānuka honey's reported beneficial effects on wound healing via topical application and anti-inflammatory actions in gastrointestinal disorder models via oral consumption.

Experimental study on self-heating strategy of lithium-ion battery at low temperatures based on bidirectional pulse current

Preheating is an effective solution to the severe degradation of lithium-ion battery (LIB) performance at low temperatures. In this study, a bidirectional pulse-current preheating strategy for LIBs at low temperatures without external power is proposed, which involves the incorporation of a direct current/direct current converter and a series of resistances, inductances, and switches. The effects of ambient temperature, initial state of charge, and preheating strategy on the voltage and current evolution, heating rate, and heating efficiency are experimentally analysed in a climatic chamber, in addition to the effects of various preheating strategies on battery degradation. A comparative analysis is conducted using the classical pulse self-heating strategy. The results indicate that the bidirectional pulse-current preheating strategy enables preheating under an ambient temperature of −15 °C at a rate of 6.38 °C/min and affords a thermal efficiency of 31.9%. By contrast, the pulse heating method affords a heating rate of 3.46 °C/min and a thermal efficiency of 24.2%. As the battery temperature decreases, both the charge/discharge switching period and heating rate decrease, whereas the thermal efficiency and energy consumption ratio improve. No significant degradation occurs after 30 heating cycles, and the bidirectional pulse-current preheating strategy is demonstrated through capacity testing, incremental capacity curves, and electrochemical impedance spectroscopy testing. This study proposes a new approach for preheating LIBs internally and provides experimental evidence for a bidirectional-pulse preheating strategy.

Predictors of futility outcomes after TAVI: insights from the France TAVI Registry

Abstract Background Transcatheter aortic valve implantation (TAVI) has revolutionized the treatment of aortic stenosis and provides a significant symptom relief and mortality reduction. However, a substantial group of patients fail to derive a benefit from TAVI, whether in terms of mortality, quality of life (QoL) or functional benefit. Objectives The aim of the present analysis was to report factors associated with a futility outcome one year after TAVI, in a national real-life registry. Methods This prospectively designed France TAVI-QoL substudy included patients from the national France TAVI registry between February the 12th 2018 and February the 12th 2019. Patient’s QoL was assessed at baseline and one year after TAVI using the EuroQol 5-Dimension 5-Level (EQ-5D-5L) questionnaire. Vital status was collected from the SNDS ("Systeme Natiobal des donnees de sante"). Factors associated with a futility outcome, defined by death or significant degradation of QoL one-year after a TAVI, were analyzed through a multivariable logistic regression. Results The mean age of the 3159 included patients was of 83 years old, and 51,1% were male. At follow-up, a total of 1055 patients (33.4%) met the primary outcome of procedure futility: 596 (18.9%) died and 459 (14.5%) had a significant decrease in QoL. The independent factors associated with procedure futility were general conditions (diabetes under insulin (RR 1.7, 95CI[1.2-2.3]; p=0.001), estimated glomerular filtration rate (odds-ratio [OR] 0.9 per 1 ml/min increase, 95CI[0.9-1.0]; p&amp;lt;0.001), chronic pulmonary disease (OR 1.6, 95CI[1.2-1.9]; p&amp;lt;0.001)), geriatric values (severe reduction in mobility (OR 1.5, 95CI[1.1-2.1]; p=0.003)), cardiologic values (supraventricular arrhythmia (OR 1.5, 95CI[1.2-1.8]; p&amp;lt;0.001), anticoagulation therapy at discharge (OR 1.3, 95CI[1.1-1.6]; p=0.01)), and procedural features (immediate complications (OR 1.5, 95CI[1.2-1.7]; p&amp;lt;0.001), and time to discharge (OR 1.1, 95CI[1.1-1.1]; p&amp;lt;0.001)). Conclusion One third of patients treated in the TAVI Qol Substudy presented with a futility outcome. Certain risk factors are potentially reversible (e.g. severe reduction in mobility or supraventricular arrhythmia), and their management might attenuate the risk of treatment futility and improve TAVI outcomes. Futility outcomes should be assessed with the growing number of patients with aortic stenosis and increasing concerns in the allocation of resources.