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It is described that the arsenic (As) removal in real groundwater by filters in one-dimensional (1D) column (30 mm diameter × 240 mm height) using mixtures of heat treated yellow loess (YL) and sand is applied with consideration of water permeability. The effluent satisfies the concentration of <10 ppb drinking water regulation before As saturation with filters. Heat treated mixture of YL and sand under 4% H2/96% Ar condition result in higher As removal capacity than heat treated one under air atmosphere condition at 500 °C for 3 hours. It is due to more evolution of Fe3O4 phase in the mixture. In order to increase As removal efficiency significantly, α-Fe2O3 coated filters on mixture of YL and sand by hydrothermal treatment at 100 °C for 12 hours are utilized. It leads to highly enhanced As removal efficiency with little Fe ions leaching but half reduction of effluent rate, appealing as an alternative of practical As removal filters.
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TiO2 nanoparticles (NPs) with their excellent photocatalytic performance are among the hottest research subjects for environmental-cleanup applications. In the present work, we developed a method of one-pot synthesis of magnesium aminoclay-titanium dioxide [MgAC-TiO2] nanocomposites in ethanol solution and then treated the obtained nanocomposites in a 350 °C muffle furnace for 3 hours. The obtained X-ray diffraction (XRD) patterns confirmed the growth of the anatase TiO2 NPs in the amorphous MgAC phase. In the scanning electron microscopy (SEM) morphological observation, the MgAC-TiO2 nanocomposites exhibited an aggregate form of 246.59 ± 54.20 nm diameter. The synthesis condition entailing loading of 0.3 g MgAC and 5 mL titanium butoxide (TB) (denoted as MgAC [0.3 g]-TiO2 in 40 mL ethanol solution displayed the largest BET surface area, 234.91 m2/g, as well as the largest pore size and pore volume, 6.7131 nm and 0.3942 cm3/g, respectively. Also, MgAC [0.3 g]-TiO2 showed the best photocatalytic performance for methylene blue (MB) on the batch scale under 365 nm wavelength irradiation: a degradation constant rate of 0.0293 min-1, which was ~20-times-better photocatalytic activity than commercial P25. On the pilot scale (100 L), the MgAC [0.3 g]-TiO2 nanocomposite took only ~12 hours to degrade almost MB at 10 ppm concentration. The mechanism of this high photocatalytic activity was determined to be the high rate of adsorption of both MgAC and oxygen vacancies in the anatase phase coupled with the retardation of the rate of recombination of electrons and holes in the TiO2 NPs, the latter proved by photoluminescent quenching tests.
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SnO2 composite materials infiltrated into the hollow carbon channels of a crab-shell biotemplate were hydrothermally synthesized and utilized as anodes for lithium-ion batteries. Varying the reaction temperatures and times of the hydrothermal reaction yielded different SnO2 nanoparticle shapes, characterized by scanning electron microscopy and transmission electron microscopy. The materials prepared at 100 °C (sample S100) were spherical, amorphous in nature, and successfully infiltrated into the hollow carbon channels, while those prepared at 180 °C (sample S180) yielded many rod-like particles on the outer surfaces of the channels. The S100 electrode exhibited better cyclability, corresponding to a capacity of 298 mAh g-1 at 100 cycles, and high rate capability with a capacity retention of 54% at 3 A g-1. The enhanced electrochemical performance of S100 could be attributed to the configuration of the SnO2 particles infiltrating the carbon-coated hollow channels, which accommodated large volume changes during (de)lithiation.
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In the present study the short term aquatic ecotoxicity of water-solubilized aminoclay nanoparticles (ANPs) of ~51±31 nm average hydrodynamic diameter was characterized. An ecotoxicological evaluation was carried out utilizing standard test organisms of different phyla and trophic levels namely the eukaryotic microalga Pseudokirchneriella subcapitata, the crustacean Daphnia magna and the bioluminescent marine bacteria Vibrio fisheri. The effective inhibitory concentration (EC50) with 95% confidence limits for the microalga was 1.29 mg/L (0.72-1.82) for the average growth rate and 0.26 mg/L (0.23-0.31) for the cell yield. The entrapping of algal cells in aggregates of ANP may play a major role in the growth inhibition of algae P. subcapitata. No inhibition was observed for V. fisheri up to 25,000 mg/L (no observed effect concentration; NOEC). For D. magna no immobilization was observed in a limit test with 100 mg/L in 24 h while in 48 h a single animal was immobilized (5% inhibition). Correspondingly, the NOEC of ANP in 24 h was 100 mg/L and the lowest observed effect concentration (LOEC) for 48 h was 100 mg/L. Therefore it can be considered to use ANP as an algal-inhibition agent at concentrations <100 mg/L without affecting or only mildly affecting other organisms including zooplanktons, but further studies on the environmental fate and chronic toxicity of ANP is needed to confirm this.
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Aliivibrio fischeri/efectos de los fármacos , Chlorophyta/efectos de los fármacos , Daphnia/efectos de los fármacos , Ecotoxicología , Nanopartículas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Daphnia/crecimiento & desarrollo , Concentración 50 Inhibidora , Agua/químicaRESUMEN
The primary objective of this study was to investigate the factors contributing to hyperglycemic adverse events (AEs) associated with the administration of remdesivir in hospitalized patients diagnosed with coronavirus disease 2019 (COVID-19). Furthermore, the study aimed to develop a risk score model employing various machine learning approaches. A total of 1262 patients were enrolled in this investigation. The relationship between covariates and hyperglycemic AEs was assessed through logistic regression analysis. Diverse machine learning algorithms were employed for the purpose of forecasting hyperglycemia-related complications. After adjusting for covariates, individuals with a body mass index ≥23 kg/m2 , those using proton pump inhibitors, cholinergic medications, or individuals with cardiovascular diseases exhibited approximately 2.41-, 2.73-, 2.65-, and 1.97-fold higher risks of experiencing hyperglycemic AEs (95% CI 1.271-4.577, 1.223-6.081, 1.168-5.989, and 1.119-3.472, respectively). Multivariate logistic regression, elastic net, and random forest models displayed area under the receiver operating characteristic curve values of 0.65, 0.66, and 0.60, respectively (95% CI 0.572-0.719, 0.640-0.671, and 0.583-0.611, respectively). This study comprehensively explored factors associated with hyperglycemic complications arising from remdesivir administration and, concurrently, leveraged a range of machine learning methodologies to construct a risk scoring model, thereby facilitating the tailoring of individualized remdesivir treatment regimens for patients with COVID-19.
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Adenosina Monofosfato/análogos & derivados , Alanina/análogos & derivados , COVID-19 , Hiperglucemia , Humanos , Tratamiento Farmacológico de COVID-19 , Factores de RiesgoRESUMEN
We report for the first time, using a simple and environmentally benign chemical method, the low temperature synthesis of densely populated upright-standing rutile TiO(2) nanoplate films onto a glass substrate from a mixture of titanium trichloride, hydrogen peroxide and thiourea in triply distilled water. The rutile TiO(2) nanoplate films (the phase is confirmed from x-ray diffraction analysis, selected area electron diffraction, energy-dispersive x-ray analysis, and Raman shift) are 20-35 nm wide and 100-120 nm long. The chemical reaction kinetics for the growth of these upright-standing TiO(2) nanoplate films is also interpreted. Films of TiO(2) nanoplates are optically transparent in the visible region with a sharp absorption edge close to 350 nm, confirming an indirect band gap energy of 3.12 eV. The Brunauer-Emmet-Teller surface area, Barret-Joyner-Halenda pore volume and pore diameter, obtained from N(2) physisorption studies, are 82 m(2) g(-1), 0.0964 cm(3) g(-1) and 3.5 nm, respectively, confirming the mesoporosity of scratched rutile TiO(2) nanoplate powder that would be ideal for the direct fabrication of nanoscaled devices including upcoming dye-sensitized solar cells and gas sensors.
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In this study, highly biocompatible three-dimensional hierarchically porous activated carbon from the low-cost silver grass (Miscanthus sacchariflorus) has been fabricated through a facile carbonization approach and tested it as bioanode in microbial fuel cell (MFC) using Escherichia coli as biocatalyst. This silver grass-derived activated carbon (SGAC) exhibited an unprecedented specific surface area of 3027 m2 g-1 with the coexistence of several micro-, meso-, and macropores. The synergistic effect from pore structure (macropores - hosting E. coli to form biofilm and facilitates internal mass transfer; mesopores - favors fast electron transfer; and micropores - promotes nutrient transport to the biofilm) with very high surface area facilitates excellent extracellular electron transfer (EET) between the anode and biofilm which resulted in higher power output of 963 mW cm-2. Based on superior biocompatibility, low cost, environment-friendliness, and facile fabrication, the proposed SGAC bioanode could have a great potential for high-performance and cost-effective sustainable MFCs.
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Fuentes de Energía Bioeléctrica , Carbón Orgánico , Electrodos , Escherichia coli , Poaceae , PlataRESUMEN
In this study, we developed a modular micronozzle system that can control the flow of fluid based on centrifugal force and synthesize functional alginate microspheres with various structures and sizes. Our method is to fabricate a programmable microreactor that can be easily manufactured without the conventional soft-lithography process using various sequences of the micronozzles with various inner diameters. To overcome the obstacles of pump-based microfluidic devices that need to be precisely controlled, we designed the programmable microreactor to be driven under centrifugal force with a combination of micronozzles, thus enabling the mass production of various functional alginate microspheres within a few minutes. The programmable microreactor designed through the arrangement of the modular micronozzles enables the formation of various types of alginate microspheres such as core-shell, Janus, and particle mixture. These materials are controlled to a size from 400 µm to 900 µm. In addition, our platform is used to generate pH-responsive smart materials, and to easily control various sizes, shapes, and compositions simultaneously. By evaluating the release process of model drugs according to the pH change, the possibility of drug delivery application is confirmed. We believe that our method can contribute to development of biomaterials engineering that has been limited by the requirement of sophisticated devices, and special skills and/or labor.
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The aim of this study was to compare chemical properties and bioactivities of with mineral trioxide aggregate (MTA) and EndoSequence Root Repair Material (ERRM). After setting, surfaces of test materials were observed by scanning electron microscope (SEM). The pH and cell viability of materials were tested. Osteoblastic differentiation and alkaline phosphatase (ALP) activity were measured by quantitative real-time PCR and ALP staining. MTA showed spindle-shaped crystals while ERRM showed round-shaped crystals of various sizes. ERRM presented lower pH than MTA. Both materials showed good cell viabilities compared to the control. Expression levels of osteoblastic genes and ALP staining were increased significantly (p<0.05) in ERRM and MTA groups compared to those in the control group. In conclusion, ERRM and MTA both had effects on osteoblastic differentiation. Therefore, ERRM can be used as a desirable alternative to MTA for root-end filling material.
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Materiales de Obturación del Conducto Radicular , Compuestos de Aluminio , Compuestos de Calcio , Diferenciación Celular , Supervivencia Celular , Combinación de Medicamentos , Óxidos , SilicatosRESUMEN
In this study, hierarchically three-dimensional (3D) nanotubular sea urchin-shaped iron oxide nanostructures (3D-Fe2O3) were synthesized by a facile and rapid ultrasound irradiation method. Additives, templates, inert gas atmosphere, pH regulation, and other complicated procedures were not required. Dense 3D-Fe2O3 with a relatively large Brunauer-Emmett-Teller (BET) surface area of 129.4â¯m2/g was synthesized within 23â¯min, and the BET surface area was further improved to 282.7â¯m2/g by a post heat-treatment process. In addition, this post processing led to phase changes from maghemite (γ phase) to hematite (α phase) Fe2O3. Subsequent characterization suggested that the growth mechanism of the 3D-Fe2O3 follows self-assembly and oriented attachment. The prepared 3D-Fe2O3 was applied to wastewater purification. Ultrasound-irradiated 3D-Fe2O3 can eliminate a As(V) and Cr(VI) from water with 25 times faster removal rate by using a one third smaller amount than commercial α-Fe2O3. This was attributed to the inter-particle pores and relatively positively charged surface of the nanostructure. In addition, post heat treatment on ultrasound-irradiated 3D-Fe2O3 significantly influenced the photocatalytic degradation of methylene blue and phenol, with a 25 times higher removal efficiency than that of commercial α-Fe2O3, because of both high BET surface area and good crystallization of the prepared samples.
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In the present study, we successfully synthesized a porous three-dimensional Prussian blue-cellulose aerogel (PB-CA) composite and used it as a decorporation agent for the selective removal of ingested cesium ions (Cs+) from the gastrointestinal (GI) tract. The safety of the PB-CA composite was evaluated through an in vitro cytotoxicity study using macrophage-like THP-1 cells and Caco-2 intestinal epithelial cells. The results revealed that the PB-CA composite was not cytotoxic. An adsorption study to examine the efficiency of the decorporation agent was conducted using a simulated intestinal fluid (SIF). The adsorption isotherm was fitted to the Langmuir model with a maximum Cs+ adsorption capacity of 13.70 mg/g in SIF that followed pseudo-second-order kinetics. The PB-CA composite showed excellent stability in SIF with a maximum Cs+ removal efficiency of 99.43%. The promising safety toxicology profile, remarkable Cs+ adsorption efficacy, and excellent stability of the composite demonstrated its great potential for use as an orally administered drug for the decorporation of Cs+ from the GI tract.
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Celulosa/química , Cesio/aislamiento & purificación , Ferrocianuros/química , Tracto Gastrointestinal/química , Administración Oral , Adsorción , Células CACO-2 , Humanos , Concentración de Iones de Hidrógeno , Cinética , Porosidad , Células THP-1RESUMEN
A novel microporous three-dimensional pomegranate-like micro-scavenger cage (P-MSC) composite has been synthesized by immobilization of iron phyllosilicates clay onto a Prussian blue (PB)/alginate matrix and tested for the removal of radioactive cesium from aqueous solution. Experimental results show that the adsorption capacity increases with increasing the inactive cesium concentration from 1 ppm to 30 ppm, which may be attributed to greater number of adsorption sites and further increase in the inactive cesium concentration has no effect. The P-MSC composite exhibit maximum adsorption capacity of 108.06 mg of inactive cesium per gram of adsorbent. The adsorption isotherm is better fitted to the Freundlich model than the Langmuir model. In addition, kinetics studies show that the adsorption process is consistent with a pseudo second-order model. Furthermore, at equilibrium, the composite has an outstanding adsorption capacity of 99.24% for the radioactive cesium from aqueous solution. This may be ascribed to the fact that the AIP clay played a substantial role in protecting PB release from the P-MSC composite by cross-linking with alginate to improve the mechanical stability. Excellent adsorption capacity, easy separation, and good selectivity make the adsorbent suitable for the removal of radioactive cesium from seawater around nuclear plants and/or after nuclear accidents.
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Blue-green microalgal blooms have been caused concerns about environmental problems and human-health dangers. For removal of such cyanobacteria, many mechanical and chemical treatments have been trialled. Among various technologies, the flocculation-based harvesting (precipitation) method can be an alternative if the problem of the low yield of recovered biomass at low concentrations of cyanobacteria is solved. In the present study, it was utilized mixtures of magnesium aminoclay [MgAC] and cerium aminoclay [CeAC] with different particle sizes to harvest cyanobacteria feedstocks with â¼100% efficiency within 1h by ten-fold lower loading of ACs compared with single treatments of [MgAC] or [CeAC]. This success was owed to the compact networks of the different-sized-ACs mixture for efficient bridging between microalgal cells. In order to determine the usage potential of biomass harvested with AC, the mass was heat treated under the reduction condition. This system is expected to be profitably utilizable in adsorbents and catalysts.
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Biomasa , Biotecnología/métodos , Cianobacterias , Microalgas , Precipitación Química , Cianobacterias/química , Cianobacterias/aislamiento & purificación , Floculación , Magnesio/química , Microalgas/química , Microalgas/aislamiento & purificaciónRESUMEN
In this study, a simple one-step hydrothermal reaction is developed to prepare composite based on Prussian blue (PB)/reduced graphene oxide foam (RGOF) for efficient removal of radioactive cesium ((137)Cs) from contaminated water. Scanning electron microscopy and transmission electron microscopy show that cubic PB nanoparticles are decorated on the RGO surface. Owing to the combined benefits of RGOF and PB, the composite shows excellent removal efficiency (99.5%) of (137)Cs from the contaminated water. The maximum adsorption capacity is calculated to be 18.67 mg/g. An adsorption isotherm fit-well the Langmuir model with a linear regression correlation value of 0.97. This type of composite is believed to hold great promise for the clean-up of (137)Cs from contaminated water around nuclear plants and/or after nuclear accidents.
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Radioisótopos de Cesio/química , Ferrocianuros/química , Grafito/química , Nanocompuestos/química , Adsorción , Óxidos , Contaminantes Radiactivos del Agua , Purificación del AguaRESUMEN
Epilepsy is a neurological disorder with recurrent unprovoked seizures as the main symptom. Of the coumarin derivatives in Angelica gigas, decursin, a major coumarin component, was reported to exhibit significant protective activity against glutamate-induced neurotoxicity when added to primary cultures of rat cortical cells. This study served to investigate the effects of decursin on a kainic acid (KA)-induced status epilepticus model. Thirty minutes after intraperitoneal injections of decursin (20 mg/kg) in male 7-week-old C57BL/6 mice, the animals were treated with KA (30 mg/kg, intraperitoneally) and then examined for behavioral seizure score, electroencephalogram, seizure-related expressed protein levels, neuronal cell loss, neurodegeneration, and astrogliosis. KA injections significantly enhanced neurodegenerative conditions but treatment with decursin 30 min before KA injection reduced the detrimental effects of KA in mice. The decursin-treated KA-injected group showed significantly decreased behavioral seizure activity and remarkably attenuated intense and high-frequency seizure discharges in the parietal cortex for 2 h compared with the group treated only with KA. Furthermore, in-vivo results indicated that decursin strongly inhibits selective neuronal death, astrogliosis, and oxidative stress induced by KA administration. Therefore decursin is able to attenuate KA-induced seizures and could have potential as an antiepileptic drug.
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Benzopiranos/farmacología , Butiratos/farmacología , Convulsiones/prevención & control , Animales , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/fisiopatología , Electroencefalografía , Agonistas de Aminoácidos Excitadores/toxicidad , Gliosis/prevención & control , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Hipocampo/patología , Ácido Kaínico/toxicidad , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-fos/metabolismo , Convulsiones/inducido químicamenteRESUMEN
Biofuels (biodiesel) production from oleaginous microalgae has been intensively studied for its practical applications within the microalgae-based biorefinement process. For scaled-up cultivation of microalgae in open ponds or, for further cost reduction, using wastewater, humic acids present in water-treatment systems can positively and significantly affect the harvesting of microalgae biomass. Flocculation, because of its simplicity and inexpensiveness, is considered to be an efficient approach to microalgae harvesting. Based on the reported cationic aminoclay usages for a broad spectrum of microalgae species in wide-pH regimes, aminoclay-induced humic acid flocculation at the 5g/L aminoclay loading showed fast floc formation, approximately 100% harvesting efficiency, which was comparable to the only-aminoclay treatment at 5g/L, indicating that the humic acid did not significantly inhibit the microalgae harvesting behavior. As for the microalgae flocculation mechanism, it is suggested that cationic nanoparticles decorated on macromolecular matters function as a type of network in capturing microalgae.
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Silicatos de Aluminio/farmacología , Chlorella/efectos de los fármacos , Chlorella/crecimiento & desarrollo , Sustancias Húmicas/análisis , Lípidos/química , Arcilla , Floculación/efectos de los fármacos , Hierro/farmacología , Cinética , Magnesio/farmacologíaRESUMEN
Electron lifetime in mesoporous nanostructured rutile TiO2 photoanodes, synthesized via a simple, cost-effective, low temperature (50-55 °C) wet chemical process, annealed at 350 °C for 1 h and not employing any sprayed TiO2 compact layer, was successfully tailored with 0.2 mM TiCl4 surface treatment that resulted in light to electric power conversion efficiency up to 4.4%.
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The hierarchically structured mesoporous LiMn(2)O(4) (LMO) nanospheres were synthesized using a template-free self-assembly process that was coupled with ultrasound (U). The ultrasound technique suggested here is very powerful for controlling an ordered nanostructure and improving crystallinity with large single-crystalline domains. Owing to the hierarchical mesoporous structure and high crystallinity, U-LMO provides an excellent rate capability and cycle stability with a capacity retention of more than 98% up to 50 cycles at a 0.2C rate. Here, we demonstrate that mesoporous U-LMO nanospheres were fabricated to enhance the electrochemical performance and protect it from structurally significant collapsing because of high crystallinity.
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Suministros de Energía Eléctrica , Litio/química , Litio/efectos de la radiación , Nanosferas/química , Nanosferas/efectos de la radiación , Óxidos/síntesis química , Sonicación/métodos , Electroquímica/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Ondas de Choque de Alta Energía , Manganeso/química , Manganeso/efectos de la radiación , Nanosferas/ultraestructura , Óxidos/química , Óxidos/efectos de la radiación , Porosidad , Dosis de RadiaciónRESUMEN
The present work reports the extraction and clean-up procedures, as well as the chromatographic conditions developed, for the determination of cafenstrole and its metabolite (CHM-03) residues in brown rice grains and rice straw using HPLC-UV detection. The method makes use of an Apollo C(18) column and acetonitrile : water : acetic acid as a mobile phase for both cafenstrole and its metabolite in rice and rice straw. Using these conditions cafenstrole and its metabolite were resolved with a retention time (R(t)) of less than 14 min. The analytes were confirmed using positive atmospheric pressure ionization LC-MS with selected ion monitoring. The average recoveries of cafenstrole were found to be 87.0-92.5 and 87.6-88.3%. However, they ranged from 81.5 to 81.6% and from 76.1 to 78.5% for cafenstrole metabolite (CHM-03), in rice grains and rice straw, respectively, with relative standard deviations ranging from 1.4 to 6.6%. The limits of detection (LODs) of both cafenstrole and its metabolite were 0.002 and 0.02 ppm and 0.025 and 0.04 ppm, respectively. Field trials with recommended or double the recommended dose revealed that the herbicide could safely be recommended for application in rice and rice straw as no residues were detected in the harvest samples.