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  • Systemic heparinization during cardiopulmonary bypass (CPB) can significantly affect thromboelastography (TEG). This study investigated the feasibility of adding protamine in vitro to allow assessment of coagulation status using the TEG 6s system during CPB.

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  • To investigate thermoregulation, thermal antinociception, food/kaolin intake, fecal output, and behavior following long-acting buprenorphine preparations in rats.

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  • Andexanet alfa neutralizes factor Xa inhibitors in critical bleeding situations. However, in cardiac surgery with cardiopulmonary bypass (CPB), heparin resistance induced by andexanet alfa should be a concern, and the lack of point-of-care monitoring of plasma concentration of factor Xa inhibitors makes it difficult to decide when to administer andexanet alfa. A 69-year-old man underwent emergency surgery for acute pulmonary thromboembolism. The patient had been on edoxaban until the day before the surgery. Withdrawal from CPB required venoarterial extracorporeal membrane oxygenation due to right heart failure, followed by severe bleeding that required massive transfusion. Despite adequate coagulation factor replacement, bleeding persisted and citrated kaolin-reaction time (CK-R) on thromboelastography (TEG) was prolonged. Administering andexanet alfa achieved excellent hemostasis without any thrombosis and normalized the prolonged CK-R of TEG. This is the first report of a change in TEG findings before and after administration of andexanet alfa in a cardiac surgery patient taking factor Xa inhibitor. Monitoring CK-R in TEG may help evaluate the anticoagulant effect of factor Xa inhibitors and the reversal effect of andexanet alfa.

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  • High temperatures and providing sufficient time for the thermal desorption of persistent organic pollutants (POPs) from contaminated clay soils can lead to intensive energy consumption. Therefore, this article provides a critical review of the potential additives which can improve soil texture and increase the volatility of POPs, and then discusses their enhanced mechanisms for contributing to a green economy. Ca-based additives have been used to reduce plasticity of bentonite clay, absorb water and replenish system heat. In contrast, non-Ca-based additives have been used to decrease the plasticity of kaolin clay. The soil structure and soil plasticity can be changed through cation exchange and flocculation processes. The transition metal oxides and alkali metal oxides can be applied to catalyze and oxidize polycyclic aromatic hydrocarbons, petroleum and emerging contaminants. In this system, reactive oxygen species (•O and •OH) are generated from thermal excitation without strong chemical oxidants. Moreover, multiple active ingredients in recycled solid wastes can be controlled to reduce soil plasticity and enhance thermal catalysis. Alternatively, the alkali, nano zero-valent iron and nano-TiN can catalyze hydrodechlorination of POPs under reductive conditions. Especially, photo and photo-thermal catalysis are discussed to accelerate replacement of fossil fuels by renewable energy in thermal remediation.

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  • Clay-algae flocculation is a promising method to remove harmful algal blooms (HABs) in aquatic ecosystems. Many HAB-generating species, such as Microcystis aeruginosa (M. aeruginosa), a common species in lakes, produce toxins and harm the environment, human health, and the economy. Natural clays, such as bentonite and kaolinite, and modification of these clays have been applied to mitigate HABs by forming large aggregates and settling down. In this study, we aim to examine the impact of laponite, a commercially available smectite clay that is synthetic, transparent, compatible with human tissues, and degradable, on removing HABs. We compare the cell removal efficiencies (RE) of laponite, two natural clays, and their polyaluminum chloride (PAC)-modified versions through clay-algae flocculation experiments. Our results show that the optimum concentrations of laponite, bentonite, kaolinite, PAC-modified bentonite, and PAC-modified kaolinite to remove 80 % of the M. aeruginosa cells from the water column are 0.05 g/L, 2 g/L, 4 g/L, 2 g/L and 0.3 g/L respectively. Therefore, to achieve the same cell removal efficiency, the amount of laponite needed is 40 to 80 times less than bentonite and kaolinite, and 6 times less than PAC-modified kaolinite. We demonstrate that the superior performance of laponite clay is because of its smaller particle size, which increases the encounter rate between cells and clay particles. Furthermore, experiments using water samples from Powderhorn Lake confirmed laponite's effectiveness in mitigating HABs. Our price analysis also suggests that this commercially-available clay, laponite, can be used in the field at a relatively low cost.

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  • Against the backdrop of "carbon neutrality", the green treatment of dye wastewater is particularly important. Currently, the adsorption method shows strong application prospects. Therefore, selecting efficient and recyclable adsorbents is of significant importance. TiO is an excellent adsorbent, but its difficult recovery often leads to secondary pollution. γ-FeO-modified coal-series kaolin exhibits both excellent adsorption properties and rapid separation through magnetic separation technology. By utilizing the synergistic effects of both, TiO/-γFeO coal-series kaolin, magnetic adsorbent regeneration materials were prepared using coprecipitation method and characterized. The influencing factors of this functional material on the adsorption of Congo red dye and its regeneration performance are discussed. The experimental results indicated that the specific surface area, pore volume and Ms value of this functional material are 127.5 m/g, 0.38 cm/g, and 13.4 emu/g, respectively. It exhibits excellent adsorption characteristics towards Congo red, with an adsorption rate reaching 96.8% within 10 min, conforming to the pseudo-second-order kinetic model, and demonstrating Langmuir IV-type monolayer adsorption. After the adsorption of Congo red, magnetic separation shows superior efficiency. Furthermore, treatment of the adsorbed composite with EDTA allows for recycling, with adsorption rates still above 91% after three cycles, indicating an excellent regeneration capability.

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  • The extraction of phosphorite ore in Tunisia has resulted in the discharge of substantial amounts of phosphatic sludge into the region's water system. To mitigate this environmental issue and prevent heavy metal leaching, a geopolymerization process was employed using two types of Tunisian calcined phosphate sludges (Cal-PS1 and Cal-PS2) as substitutes for alkali-activated metakaolin. This study aimed to investigate and compare the physical and mechanical properties of the resulting geopolymers. The optimal substitution ratio of metakaolin with calcined phosphate sludge was determined to be 1.5, equivalent to 20 wt.% of calcined phosphate sludge. Compressive strength tests conducted after 28 days of curing revealed values of 37 MPa for Cal-PS1 specimens and 28 MPa for Cal-PS2 geopolymers while compressive strength of geopolymers soaked in water for 28 days showed a decrease with the addition of phosphate sludges. The specific surface areas of Cal-PS1 geopolymers ranged from 16.3 to 16.9 m/g and from 17.62 to 18.73 m/g for Cal-PS2 specimens exhibiting a mesoporous structure. The elasticity modulus of the geopolymers was found to increase with the increase of the apparent density of geopolymers and with the sludges content but it tended to be lower than the Portland cement elasticity modulus. Leaching test was conducted to evaluate the potential environmental applications of the geopolymers. This test demonstrated effective containment of heavy metals within the geopolymers' network, except for low levels of arsenic.

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  • In accordance with the framework of the Circular Blue Bioeconomy in the Mediterranean region, the objective of this study was to evaluate the biotransformation of blue swimming crab (Portunus segnis) residues obtained from the port of Sfax by an extracellular chitinase produced by Nocardiopsis halophila strain TN-X8 isolated from Chott El Jerid (Tozeur, Tunisia). From the analysis of multiple extremophilic Actinomycetota, it was determined that strain TN-X8 exclusively utilized 60 g/L of raw blue swimming crab as its carbon and energy source, achieving a chitinase activity of approximately 950 U/mL following a 6-day incubation period at 40 °C. Pure chitinase, designated as ChiA-Nh30, was obtained after heat treatment, followed by ammonium sulfate fractionation and Sephacryl® S-200 column chromatography. The maximum ChiA-Nh30 activity was observed at pH 3 and 75 °C. Interestingly, compared with cyclohexamidine, ChiA-Nh30 showed a good antifungal effect against four pathogenic fungi. Furthermore, when using colloidal chitin as substrate, ChiA-Nh30 demonstrated a higher degree of catalytic efficiency than the commercially available Chitodextrinase®. In addition, ChiA-Nh30 could be immobilized by applying encapsulation and encapsulation-adsorption techniques. The kaolin and charcoal used acted as excellent binders, resulting in improved ChiA-Nh30 stability. For the immobilized ChiA-Nh30, the yield of N-acetyl-D-glucosamine monomers released from 20% (w/v) blue swimming crab residues increased by 3.1 (kaolin) and 2.65 (charcoal) times, respectively.

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  • This study surveyed the fates of artificial sweeteners in influent, effluent, and sewage sludge (SS) in wastewater treatment plant, and investigated the effects of Micro-Kaolin (Micro-KL) and Nano-Kaolin (Nano-KL) on nitrogen transformation and sucralose (SUC) and acesulfame (ACE) degradation during SS composting. Results showed the cumulative rate of ACE and SUC in SS was ∼76 %. During SS composting, kaolin reduced NH emissions by 30.2-45.38 %, and NO emissions by 38.4-38.9 %, while the Micro-KL and Nano-KL reduced nitrogen losses by 14.8 % and 12.5 %, respectively. Meanwhile, Micro-KL and Nano-KL increased ACE degradation by 76.8 % and 84.2 %, and SUC degradation by 75.3 % and 77.7 %, and significantly shifted microbial community structure. Furthermore, kaolin caused a positive association between Actinobacteria and sweetener degradation. Taken together, kaolin effectively inhibited nitrogen loss and promoted the degradation of ACE and SUC during the SS composting, which is of great significance for the removal of emerging organic pollutants in SS.

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  • Clay minerals are ubiquitous in subsurface environments and have long been recognized as having a limited or negligible impact on the fate of arsenic (As) due to their negatively charged surfaces. Here, we demonstrate the significant role of kaolinite (Kln), a pervasive clay mineral, in enhancing As(V) immobilization during ferrous iron (Fe(II)) oxidation at near-neutral pH. Our results showed that Fe(II) oxidation alone was not capable of immobilizing As(V) at relatively low Fe/As molar ratios (≤2) due to the generation of Fe(III)-As(V) nanocolloids that could still migrate easily as truly dissolved As did. In the presence of kaolinite, dissolved As(V) was significantly immobilized on the kaolinite surfaces via forming Kln-Fe(III)-As(V) ternary precipitates, which had large sizes (at micrometer levels) to reduce the As mobility. The kaolinite-induced heterogeneous pathways for As(V) immobilization involved Fe(II) adsorption, heterogeneous oxidation of adsorbed Fe(II), and finally heterogeneous nucleation/precipitation of Fe(III)-As(V) phases on the edge surfaces of kaolinite. The surface precipitates were mixtures of amorphous basic Fe(III)-arsenate and As-rich hydrous ferric oxide. Our findings provide new insights into the role of clay minerals in As transformation, which is significant for the fate of As in natural and engineered systems.

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