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1.
Environ Res ; 262(Pt 2): 119987, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39270961

RESUMEN

This study explored the use of waste from the textile industry (silkworm byproducts) as a promising raw feedstock for the production of carbon-based adsorbents (biochar). The silk excreta biochar generated at 600 and 700 °C (referred to as SEB-600 and SEB-700, respectively) were evaluated in terms of their efficacy in adsorbing cationic (methylene blue) and anionic (Congo red) textile dyes. Although the functional groups on the surfaces of SEB-600 and SEB-700 were not significantly different, the specific surface area of SEB-700 was greater than that of SEB-600. The dye adsorption capacity of SEB-700 was higher than that of SEB-600. The adsorption of methylene blue and Congo red on SEB-700 followed Freundlich isotherms (R2 ≥ 0.963) and pseudo-second-order kinetics (R2 = 0.999), indicating chemisorption with multilayer characteristics. The mechanism for the adsorption of methylene blue on SEB-700 may involve interactions with the negatively charged functional groups on the surface and the mesopores of SEB-700. For the adsorption of Congo red, the mesopores in the biochar and the electrostatic interaction between biochar (positively charged because of the dye solution pH < pHzpc) and the anionic dye could affect adsorption. The maximum adsorption capacities of SEB-700 for methylene blue and Congo red were determined to be 168.23 and 185.32 mg g-1, respectively. Utilising the waste generated from the textile industry to remove pollutants will build a sustainable loop in the industry by minimising waste generation and pollutant emissions.

2.
Crit Care ; 27(1): 286, 2023 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-37443130

RESUMEN

BACKGROUND: To maintain adequate oxygenation is of utmost importance in intraoperative care. However, clinical evidence supporting specific oxygen levels in distinct surgical settings is lacking. This study aimed to compare the effects of 30% and 80% oxygen in off-pump coronary artery bypass grafting (OPCAB). METHODS: This multicenter trial was conducted in three tertiary hospitals from August 2019 to August 2021. Patients undergoing OPCAB were cluster-randomized to receive either 30% or 80% oxygen intraoperatively, based on the month when the surgery was performed. The primary endpoint was the length of hospital stay. Intraoperative hemodynamic data were also compared. RESULTS: A total of 414 patients were cluster-randomized. Length of hospital stay was not different in the 30% oxygen group compared to the 80% oxygen group (median, 7.0 days vs 7.0 days; the sub-distribution hazard ratio, 0.98; 95% confidence interval [CI] 0.83-1.16; P = 0.808). The incidence of postoperative acute kidney injury was significantly higher in the 30% oxygen group than in the 80% oxygen group (30.7% vs 19.4%; odds ratio, 1.94; 95% CI 1.18-3.17; P = 0.036). Intraoperative time-weighted average mixed venous oxygen saturation was significantly higher in the 80% oxygen group (74% vs 64%; P < 0.001). The 80% oxygen group also had a significantly greater intraoperative time-weighted average cerebral regional oxygen saturation than the 30% oxygen group (56% vs 52%; P = 0.002). CONCLUSIONS: In patients undergoing OPCAB, intraoperative administration of 80% oxygen did not decrease the length of hospital stay, compared to 30% oxygen, but may reduce postoperative acute kidney injury. Moreover, compared to 30% oxygen, intraoperative use of 80% oxygen improved oxygen delivery in patients undergoing OPCAB. Trial registration ClinicalTrials.gov (NCT03945565; April 8, 2019).


Asunto(s)
Lesión Renal Aguda , Puente de Arteria Coronaria Off-Pump , Daucus carota , Humanos , Puente de Arteria Coronaria/efectos adversos , Oxígeno/uso terapéutico , Puente de Arteria Coronaria Off-Pump/efectos adversos , Lesión Renal Aguda/complicaciones , Resultado del Tratamiento , Complicaciones Posoperatorias/epidemiología
3.
Medicina (Kaunas) ; 58(10)2022 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-36295533

RESUMEN

High-risk surgeries for patients with severe aortic stenosis (AS) are challenging for anesthesiologists and can result in hemodynamic deterioration and even mortality. We describe a case in which remimazolam was used to induce and maintain general anesthesia for a high-risk, noncardiac surgery accompanied by ongoing bleeding. An 86-year-old man with severe AS was scheduled to undergo proximal gastrectomy due to ongoing gastrointestinal bleeding and severe anemia. Remimazolam, a novel, ultra-short-acting benzodiazepine, was administered along with remifentanil for the induction and maintenance of general anesthesia. Throughout the anesthetic process, the patient's cardiac index and systemic vascular resistance were well preserved without any vasopressor support. Remimazolam seems to have possible effectiveness as a relatively safe agent for the induction and maintenance of general anesthesia in patients with severe AS who are undergoing high-risk, noncardiac surgery with bleeding.


Asunto(s)
Estenosis de la Válvula Aórtica , Masculino , Humanos , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/cirugía , Remifentanilo , Anestesia General/efectos adversos , Benzodiazepinas
4.
Environ Geochem Health ; 43(9): 3263-3272, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32705387

RESUMEN

This review summarizes the mechanisms for desorbing and extracting cesium (Cs+) from clay minerals and soil. Most techniques use ion exchange with acids, cations, polymers, and surfactants. Some improve desorption of Cs+ from clay minerals, while surfactants and polymers expand the interlayer. Mixtures of acids/polymers, acids/surfactants, cations/polymers, and cations/surfactants are therefore more effective agents for desorption of Cs+ from clay minerals. Hydrothermal treatment plays a role similar to that of polymers and surfactants in expanding the interlayer of clay minerals. The primary desorption mechanism expands the interlayer and desorbs Cs+, but multiple sequential extractions based on these techniques can more effectively desorb Cs+ from clay minerals and field-contaminated soils. Desorption techniques for Cs+ based on multiple sequential extractions can reportedly achieve an efficiency greater than 90%, and such approaches are likely to be important technologies for remediation of Cs+-contaminated soils and industrial accident sites, as well as the dismantling of nuclear power plants.


Asunto(s)
Cesio , Contaminantes Radiactivos del Suelo , Adsorción , Cesio/análisis , Arcilla , Suelo , Contaminantes Radiactivos del Suelo/análisis
5.
Environ Res ; 188: 109832, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32798950

RESUMEN

Iron-modified graphitic carbon nitride (FG materials) was prepared through a simple and cost-effective method using iron oxide and melamine to achieve simultaneous oxidation and adsorption of arsenic. We hypothesized that graphitic carbon nitride oxidizes As(III) to As(V) under light irradiation, and the converted As(V) is adsorbed by the amorphous iron phase on FG materials. FG materials were characterized by X-ray diffraction, Fourier transform infrared spectra, field-emission scanning electron microscopy, specific surface area, ultraviolet-visible light spectroscopy, photoluminescence, and X-ray photoelectron spectroscopy. As(III) was efficiently transformed to As(V) due to the photocatalytic-oxidation ability of graphic carbon nitride under visible and UV light irradiation, the oxidized As(V) was adsorbed by the amorphous iron phases, and As species were removed from the system. The removal efficiency of As(III) decreased from 50%, 41%, and 33% under UV light, visible light and dark, respectively. FG materials exhibited the photocatalytic-oxidation ability and adsorption capacity, and a synergistic effect was observed between graphitic carbon nitride and iron oxide. Removal of As can be achieved even under visible light, confirming the field applicability of low-cost FG materials.


Asunto(s)
Arsénico , Adsorción , Catálisis , Grafito , Hierro , Luz , Compuestos de Nitrógeno
6.
Sensors (Basel) ; 18(10)2018 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-30360413

RESUMEN

Internet of Things (IoT)-based devices, especially those used for home automation, consist of their own sensors and generate many logs during a process. Enterprises producing IoT devices convert these log data into more useful data through secondary processing; thus, they require data from the device users. Recently, a platform for data sharing has been developed because the demand for IoT data increases. Several IoT data marketplaces are based on peer-to-peer (P2P) networks, and in this type of marketplace, it is difficult for an enterprise to trust a data owner or the data they want to trade. Therefore, in this study, we propose a review system that can confirm the reputation of a data owner or the data traded in the P2P data marketplace. The traditional server-client review systems have many drawbacks, such as security vulnerability or server administrator's malicious behavior. However, the review system developed in this study is based on Ethereum smart contracts; thus, this system is running on the P2P network and is more flexible for the network problem. Moreover, the integrity and immutability of the registered reviews are assured because of the blockchain public ledger. In addition, a certain amount of gas is essential for all functions to be processed by Ethereum transactions. Accordingly, we tested and analyzed the performance of our proposed model in terms of gas required.

7.
J Phys Ther Sci ; 30(8): 1103-1107, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30154609

RESUMEN

[Purpose] This study aimed to investigate the effects of McKenzie exercise, Kinesio taping, and myofascial release (MFR) on forward head posture (FHP). [Participants and Methods] Twenty-eight individuals with an FHP were enrolled. participants were randomly assigned to one of three groups: Group A, Group B and Group C. Group A underwent McKenzie exercise and MFR. Group B underwent McKenzie exercise and Kinesio taping. Group C underwent McKenzie exercise, MFR, and Kinesio taping. Interventions for all three groups were provided three times per week for four weeks. The acromion and tragus of ear (A-T length), craniovertebral angle (CVA), Cranial rotation angle (CRA), and neck disability index (NDI) were measured. [Results] The A-T length significantly differed after intervention in all three groups. CVA only significantly differed after intervention in group C. All three groups showed an increase in CRA after intervention; however, these increases were not statistically significant. [Conclusion] Considering these results, these three types of exercise may be recommended as effective exercises to improve posture in adults with FHP.

8.
BMC Anesthesiol ; 15: 17, 2015 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-25971886

RESUMEN

BACKGROUND: Dexmedetomidine (DMT), a highly selective α2-adrenoceptor agonist, has been used safely as a sedative in patients under regional anesthesia. The purpose of this study was to determine the 50% effective dose (ED50) of single-dose DMT to induce adequate light sedation in elderly patients in comparison with younger patients undergoing transurethral resection of the prostate (TURP) with spinal anesthesia. METHODS: Forty-two male patients were recruited. The young age group (Group Y) included patients 45 to 64 years old and the old age group (Group O) included patients 65 to 78 years old. After the spinal anesthesia was performed, a pre-calculated dose of DMT was administered for 10 min. The Observer's Assessment of Alertness/Sedation (OAA/S) scale, bispectral index score (BIS) were assessed then at 2-min intervals for 20 min. A modified Dixon's up-and-down method was used to determine the ED50 of the drug for light sedation (OAA/S score 3/4). In the recovery room, regression times of the motor and sensory blocks were recorded. RESULTS: The ED50 of DMT was 0.25 (95% C.I. 0.15-0.35) µg/kg in Group O and 0.35 (95% C.I. 0.35-0.45) µg/kg in Group Y (p = 0.002). The ED95 was 33% lower in Group O compare with Group Y (0.38 (95% C.I. 0.29-0.39) µg/kg vs. 0.57 (95% C.I. 0.49-0.59) µg/kg). The regression time of sensory block was longer in Group O than in Group Y (109.0 ± 40.2 min vs. 80.0 ± 31.6 min) (p = 0.014). CONCLUSION: The single-dose of DMT for light sedation was lower by 21% in Group O compare with Group Y underwent TURP with spinal anesthesia. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01665586. Registered July 31, 2012.


Asunto(s)
Agonistas de Receptores Adrenérgicos alfa 2/administración & dosificación , Dexmedetomidina/administración & dosificación , Hipnóticos y Sedantes/administración & dosificación , Resección Transuretral de la Próstata/métodos , Adulto , Factores de Edad , Anciano , Anestesia Raquidea/métodos , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Hemodinámica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad
9.
Chemosphere ; 349: 140817, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38040260

RESUMEN

Metal-based anodes have been used for a long time in the electrochemical oxidation processes to remediate groundwater. However, the high cost of this technique as well as the release of potentially toxic metals (ex, lead), are major barriers being fully implemented. As an alternative of metal-based anodes, in recent years, carbon-based anodes have been paid attention due to their eco-friendliness and cost-effectiveness. This study evaluated the oxidation performance of carbon fiber (CF) anode in a flow-through system. The CF anode degraded 45-87% of the target pollutant (sulfanilamide), depending on the current intensity applied. However, no further degradation of sulfanilamide was observed after the cathode, indicating that sulfanilamide degradation occurred mainly at the anode. This study also determined the effect of electrolytes on electrochemical oxidation using chloride (Cl-), sulfate (SO42-), bicarbonate (CO3-), and synthetic groundwater. Cl- and SO42- electrolytes were converted electrochemically into active species, thereby enhancing sulfanilamide degradation, while the bicarbonate and groundwater electrolytes inhibited oxidation performance by scavenging hydroxyl radicals. A series of scavenger tests and characterization showed that the direct oxidation and hydroxyl radicals involved the sulfanilamide degradation. Especially, the production of hydroxyl radicals is more favorable in high currents than in low currents. That is, CF anode contributed to the degradation by direct oxidation of carbon-based electrodes and generation of hydroxyl radicals. In summary, this study highlights how a CF anode is capable of effectively degrading organic pollutants via anodic oxidation.


Asunto(s)
Bicarbonatos , Contaminantes Químicos del Agua , Sulfanilamida , Fibra de Carbono , Contaminantes Químicos del Agua/química , Oxidación-Reducción , Carbono , Electrodos , Radical Hidroxilo/química
10.
Nutr Res Pract ; 18(3): 309-324, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38854466

RESUMEN

BACKGROUND/OBJECTIVES: This study evaluated the beneficial effects of an ethanol extract of Boswellia serrata gum resin (FJH-UBS) in osteoporosis. MATERIALS/METHODS: MC3T3-E1 osteoblastic cells and RAW 264.7 osteoclastic cells were treated with FJH-UBS. The alkaline phosphatase (ALP) activity, mineralization, collagen synthesis, osteocalcin content, and Runt-related transcription factor 2 (RUNX2) and Osterix expression were measured in MC3T3-E1 cells. The actin ring structures, tartrate-resistant acid phosphatase (TRAP) activity, and the nuclear factor of activator T-cells, cytoplasm 1 (NFATc1) expression were evaluated in RAW 264.7 cells. Ovariectomized ICR mice were orally administered FJH-UBS for eight weeks. The bone mineral density (BMD) and the serum levels of osteocalcin, procollagen 1 N-terminal propeptide (P1NP), osteoprotegerin, and TRAP 5b were analyzed. RESULTS: FJH-UBS increased the ALP activity, collagen, osteocalcin, mineralization, and RUNX2 and osterix expression in MC3T3-E1 osteoblastic cells, whereas it decreased the TRAP activity, actin ring structures, and NFATc1 expression in RAW 264.7 osteoclastic cells. In ovariectomy-induced osteoporosis mice, FJH-UBS positively restored all of the changes in the bone metabolism biomarkers (BMD, osteocalcin, P1NP, osteoprotegerin, and TRAP 5b) caused by the ovariectomy. CONCLUSION: FJH-UBS has anti-osteoporotic activity by promoting osteoblast activity and inhibiting osteoclast activity in vitro and in vivo, suggesting that FJH-UBS is a potential functional food ingredient for osteoporosis.

11.
Chemosphere ; 366: 143392, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39343320

RESUMEN

Electrochemical oxidation has emerged as an effective and straightforward technology for groundwater remediation. While recent studies have investigated parameters such as current, electrolyte composition, and electrode materials, most have been conducted using small-scale batch or flow reactors, limiting their applicability to real-world conditions. In this study, a pilot-scale sandbox reactor was employed to simulate realistic groundwater conditions and assess the removal of sulfanilamide, a model organic contaminant. Various electrode configurations were systematically evaluated to identify the key operational parameters influencing pollutant removal efficiency, providing insights for practical applications in groundwater treatment. This study proposes three configurations, including a single well with the anode and cathode, a double well with the separated anode and cathode, and an e-barrier with electrodes separately mounted inside a permeable barrier. Single well had the lowest removal efficiency (60%) because cathodic reaction inhibited the anodic oxidation. A double well with a separate anode and cathode can achieve 80% removal efficiency. However, effluent pH can reach up to 13.2, which can adversely impact groundwater. Meanwhile, the e-barrier not only achieved complete removal, but also maintained a neutral pH of 7.0 over 30 days. The e-barriers proved to be the most effective configuration based on their removal efficiency (100%) while yielding an effluent with neutral pH. The energy consumption of the e-barrier was most effective at 1.54 kWh/m3, while the other configurations were 5.40 and 22.18 kWh/m3. E-barriers are deemed a very reasonable configuration, both in terms of removal efficiency and practical application in groundwater.

12.
J Hazard Mater ; 476: 134990, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38908179

RESUMEN

Arsenic (As) is a widespread environmental contaminant that poses a significant threat to ecosystems and human health. Although previous studies have qualitatively revealed the effects of individual soil properties on the transport and fate of As in the vadose zone, their integrated impacts remain obscure. Moreover, studies investigating the retardation factor therein, which is a key parameter for comprehending As transport in the vadose zone, are extremely limited. In this study, we investigated the interplay of soil properties with As transport and retention within the vadose zone, while focusing on the retardation factor of As. We employed steady-state unsaturated water-flow soil column experiments coupled with a mobile-immobile model and multiple linear regression analysis to elucidate the dependence of As retardation factors on the soil properties. In the mobile water zone, iron and organic matter contents emerged as the two most influential properties that impedes As mobility. Whereas, in the immobile water zone, the coefficient of uniformity and bulk density were the most influential factors that enhanced As retention. Finally, we derived an empirical equation for calculating the As retardation factors in each zone, offering a valuable tool for describing and predicting As behavior to protect the groundwater resources underneath.

13.
Crit Care ; 17(5): R254, 2013 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-24156702

RESUMEN

INTRODUCTION: Recombinant human erythropoietin (EPO) is known to provide organ protection against ischemia-reperfusion injury through its pleiotropic properties. The aim of this single-site, randomized, case-controlled, and double-blind study was to investigate the effect of pre-emptive EPO administration on the incidence of postoperative acute kidney injury (AKI) in patients with risk factors for AKI undergoing complex valvular heart surgery. METHODS: We studied ninety-eight patients with preoperative risk factors for AKI. The patients were randomly allocated to either the EPO group (n = 49) or the control group (n = 49). The EPO group received 300 IU/kg of EPO intravenously after anesthetic induction. The control group received an equivalent volume of normal saline. AKI was defined as an increase in serum creatinine >0.3 mg/dl or >50% from baseline. Biomarkers of renal injury were serially measured until five days postoperatively. RESULTS: Patient characteristics and operative data, including the duration of cardiopulmonary bypass, were similar between the two groups. Incidence of postoperative AKI (32.7% versus 34.7%, P = 0.831) and biomarkers of renal injury including cystatin C and neutrophil gelatinase-associated lipocalin showed no significant differences between the groups. The postoperative increase in interleukin-6 and myeloperoxidase was similar between the groups. None of the patients developed adverse complications related to EPO administration, including thromboembolic events, throughout the study period. CONCLUSIONS: Intravenous administration of 300 IU/kg of EPO did not provide renal protection in patients who are at increased risk of developing AKI after undergoing complex valvular heart surgery. TRIAL REGISTRATION: Clinical Trial.gov, NCT01758861.


Asunto(s)
Lesión Renal Aguda/prevención & control , Eritropoyetina/uso terapéutico , Enfermedades de las Válvulas Cardíacas/cirugía , Hematínicos/uso terapéutico , Complicaciones Posoperatorias/prevención & control , Lesión Renal Aguda/epidemiología , Biomarcadores/sangre , Puente Cardiopulmonar , Estudios de Casos y Controles , Método Doble Ciego , Epoetina alfa , Femenino , Hematócrito , Humanos , Incidencia , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Proteínas Recombinantes/uso terapéutico , Factores de Riesgo , Resultado del Tratamiento
14.
Sci Total Environ ; 886: 163891, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37142015

RESUMEN

Biochar (BC) has received much attention as a promising adsorbent that can be exploited to remove heavy metals in domestic and wastewater. The adsorption capacity of BC is, however, relatively low compared to that of conventional adsorbents, and its performance is inversely proportional to its stability. Various chemical and physical methods have been tried to address these limitations, but BC activation still generates too much acidic or alkaline wastewater. Here we propose a novel electrochemical method and compare its lead (Pb) adsorption capacity to that of acid- and alkaline-based approaches. We found that electrochemical activation significantly increased the number of hydroxyl and carboxylic groups on the BC surface, which led to an increase in Pb absorption from 27 % (pristine BC) to 100 % because the oxygenated-functional groups contributed to the adsorption of Pb. Pb capacity was 1.36, 2.64, 3.31, and 5.00 mg g-1, corresponding to pristine, acidic, alkaline, and electrochemical activation, respectively. The Pb absorption capacity of electrochemically activated BC was also higher than that of acid- and alkali-activated BC, which we attribute to the observed increases in oxygen ratio and surface area. Moreover, the adsorption rate of BC after electrochemical activation was 190 times faster and its capacity was 2.4 times higher than that of pristine BC. These findings show that the electrochemical activation of BC results in greater adsorption capacity than conventional methods.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Café , Plomo , Adsorción , Contaminantes Químicos del Agua/análisis , Carbón Orgánico , Cinética
15.
Appl Spectrosc ; 77(6): 603-615, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37097821

RESUMEN

In this study, we propose a transfer learning-based classification model for identifying scrap metal using an augmented training dataset consisting of laser-induced breakdown spectroscopy (LIBS) measurement of standard reference material (SRMs) samples, considering varying experimental setups and environmental conditions. LIBS provides unique spectra for identifying unknown samples without complicated sample preparation. Thus, LIBS systems combined with machine learning methods have been actively studied for industrial applications such as scrap metal recycling. However, in machine learning models, a training set of the used samples may not cover the diversity of the scrap metal encountered in field measurements. Moreover, differences in experimental configuration, where laboratory standards and real samples are analyzed in situ, may lead to a wider gap in the distribution of training and test sets, dramatically reducing the performance of the LIBS-based fast classification system for real samples. To address these challenges, we propose a two-step Aug2Tran model. First, we augment the SRM dataset by synthesizing spectra of unobserved types through attenuation of dominant peaks corresponding to sample composition and generating spectra depending on the target sample using a generative adversarial network. Second, we used the augmented SRM dataset to build a robust real-time classification model with a convolutional neural network, which is further customized for the target scrap metal with limited measurements through transfer learning. For evaluation, SRMs of five representative metal types, including aluminum, copper, iron, stainless steel, and brass, are measured with a typical setup to form the SRM dataset. For testing, scrap metal from actual industrial fields is experimented with three different configurations, resulting in eight different test datasets. The experimental results show that the proposed scheme produces an average classification accuracy of 98.25% for the three experimental conditions, as high as the results of the conventional scheme with three separately trained and executed models. Additionally, the proposed model improves the classification accuracy of arbitrarily shaped static or moving samples with various surface contaminations and compositions, and even for differing ranges of charted intensities and wavelengths. Therefore, the proposed Aug2Tran model can be used as a systematic model for scrap metal classification with generalizability and ease of implementation.


Asunto(s)
Aluminio , Metales , Contaminación de Medicamentos , Análisis Espectral , Rayos Láser
16.
Chemosphere ; 324: 138321, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36878361

RESUMEN

Biochar has a great potential in the stabilization of soil heavy metals; however, the application can actually enhance the mobility of Arsenic (As) in soil. Here, a biochar-coupled calcium peroxide system was proposed to control the increase in As mobility caused by biochar amendment in paddy soil environment. The capability of rice straw biochar pyrolyzed at 500 °C (RB) and CaO2 to control As mobility was evaluated by incubation for 91 days. CaO2 encapsulation was performed for pH control of CaO2, and As mobility was evaluated using a mixture of RB + CaO2 powder (CaO2-p), and RB + CaO2 bead (CaO2-b), respectively. The control soil solely and RB alone were included for comparison. The combination of RB with CaO2 exhibited remarkable performance in controlling As mobility in soil, and As mobility decreased by 40.2% (RB + CaO2-p) and 58.9% (RB + CaO2-b) compared to RB alone. The result was due to high dissolved oxygen (6 mg L-1 in RB + CaO2-p and RB + CaO2-b) and calcium concentrations (296.3 mg L-1 in RB + CaO2-b); oxygen (O2) and Ca2+ derived from CaO2 is able to prevent the reductive dissolution and chelate-promoted dissolution of As bound to iron (Fe) oxide by biochar. This study revealed that the simultaneous application of CaO2 and biochar could be a promising way to mitigate the environmental risk of As.


Asunto(s)
Arsénico , Oryza , Contaminantes del Suelo , Arsénico/análisis , Oryza/metabolismo , Suelo , Carbón Orgánico/metabolismo , Contaminantes del Suelo/análisis
17.
Chemosphere ; 312(Pt 1): 137218, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36370757

RESUMEN

Enzyme-based biocatalytic treatment has been known as an effective measure to biologically degrade organic pollutants. Advantageously, enzymes could be immobilized on solid supports, and such fact enables reuse/prolong the enzymatic capability. It could be of great importance to functionalize a support material for enhancing the immobilization efficiency/stability of enzymes. As such, this study laid great emphasis on covalent bonding to immobilize horseradish peroxidase (HRP) on a functionalized rice straw biochar with glutaraldehyde (GA) as a crosslinker. Biochar was pretreated by the electrochemical method and the acid treatment respectively to enrich the oxygen-containing functional groups. These led to the enhanced immobilizing ability of biochar. The HRP immobilized on the electrochemically-functionalized biochar (HRP-EBC) showed three times as much enzyme activity as the HRP directly adsorbed onto biochar. The HRP immobilized on the acid-functionalized biochar (HRP-ABC) showed activity similar to that of HRP-EBC. It was concluded that both the (acid/electrochemical) pretreatments are effective to enhance enzyme immobilization. Nevertheless, the electrochemical functionalized method of biochar is chemical oxidant-free, and one important lesson from a series of tests was that the pretreatment of biochar through the electrochemical method could be more environmentally benign. Moreover, employing HRP-EBC could be beneficial from a perspective of a real environmental practice considering its higher pH, thermal stability, and good reusability. 80% of phenol was degraded in 1 h in the presence of HRP-EBC when pH was 7.0 and a ratio of H2O2 to phenol was 1:1.5.


Asunto(s)
Peróxido de Hidrógeno , Fenol , Peroxidasa de Rábano Silvestre/metabolismo , Estabilidad de Enzimas , Temperatura , Enzimas Inmovilizadas/metabolismo , Fenoles
18.
Bioeng Transl Med ; 8(1): e10362, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36684086

RESUMEN

Adoptive cell therapy (ACT) with antigen-specific T cells is a promising treatment approach for solid cancers. Interleukin-2 (IL-2) has been utilized in boosting the efficacy of ACT. However, the clinical applications of IL-2 in combination with ACT is greatly limited by short exposure and high toxicities. Herein, a complex coacervate was designed to intratumorally deliver IL-2 in a sustained manner and protect against proteolysis. The complex coacervate consisted of fucoidan, a specific IL-2 binding glycosaminoglycan, and poly-l-lysine, a cationic counterpart (FPC2). IL-2-laden FPC2 exhibited a preferential bioactivity in ex vivo expansion of CD8+T cells over Treg cells. Additionally, FPC2 was embedded in pH modulating injectable gel (FPC2-IG) to endure the acidic tumor microenvironment. A single intratumoral administration of FPC2-IG-IL-2 increased expansion of tumor-infiltrating cytotoxic lymphocytes and reduced frequencies of myeloid populations. Notably, the activation and persistency of tumor-reactive T cells were observed only in the tumor site, not in the spleen, confirming a localized effect of FPC2-IG-IL-2. The immune-favorable tumor microenvironment induced by FPC2-IG-IL-2 enabled adoptively transferred TCR-engineered T cells to effectively eradicate tumors. FPC2-IG delivery system is a promising strategy for T-cell-based immunotherapies.

19.
J Hazard Mater ; 432: 128751, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35344889

RESUMEN

The mobilization of As in paddy soils is affected by iron redox cycles. In this regard, calcium peroxide (CaO2) can be used as an alternative to maintaining oxidizing conditions by liberating oxygen under flooding environments. Nevertheless, the problem of increase in pH by CaO2 dissolution remains unresolved. In this study, the encapsulation of CaO2 using alginate is proposed. Encapsulated CaO2 (CaO2-b) using 1% sodium alginate was applied to As-contaminated soil to evaluate the ability of pH control and As mobility during flooding conditions. The pH increased rapidly from 6.8 to 9.0 in unencapsulated CaO2 (CaO2-p) within 1 day, while CaO2-b increased slowly to 8.6 over 91 days. CaO2 created an oxidizing condition in the soil by providing oxygen, thus effectively prevented the reductive dissolution of iron. The mobility of As decreased by 50% (CaO2-p) and 83% (CaO2-b) compared with that of the control soil. Furthermore, the As in pore water was three times lower than CaO2-p because CaO2-b released 1.8 times more Ca2+ to form Ca-As complexes than CaO2-p. Consequently, the encapsulated CaO2 reduced the negative effects of CaO2 treatment on increasing pH of the soil and furnished a better environmental condition for inhibiting As mobility.


Asunto(s)
Arsénico , Contaminantes del Suelo , Alginatos , Arsénico/química , Hierro , Oxígeno , Peróxidos , Suelo/química , Contaminantes del Suelo/análisis
20.
Chemosphere ; 292: 133336, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34922955

RESUMEN

Total organic carbon (TOC), total nitrogen (TN), and total phosphorous (TP) are the most common indicators of water quality. The analytical processes of the indicators require oxidation of any type of C, N, and P to carbon dioxide, nitrate, and phosphate as final products. Persulfate is the recommended oxidant for these transformations. In this study, co-oxidation was suggested for the simultaneous analysis of TOC-TN-TP. A single oxidizing reactor using persulfate was proposed instead of three individual systems. The system oxidizes complex organic chemicals to carbon dioxide, nitrate, and phosphate. However, the residual persulfate after oxidation interferes with the spectrophotometric analysis of nitrate and phosphate. Therefore, in the proposed system, the complete transformation of persulfate is a key factor for simultaneous analysis. In this system, ultraviolet irradiation for 30 min under alkaline conditions converted residual persulfate to sulfate. The complete transformation eliminated persulfate interference in nitrate and phosphate detection. In the proposed system with a single oxidation reactor, TOC, TN, and TP were oxidized and analyzed simultaneously within 15% of the analytical error range compared to the standard test method.


Asunto(s)
Nitrógeno , Contaminantes Químicos del Agua , Oxidación-Reducción , Fósforo , Sulfatos
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