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Electrocatalytic nitrate reduction reaction offers a sustainable approach to treating wastewater and synthesizing high-value ammonia under ambient conditions. However, electrocatalysts with low faradaic efficiency and selectivity severely hinder the development of nitrate-to-ammonia conversion. Herein, Ru-doped ultrasmall copper nanoparticles loaded on a carbon substrate (Cu-Ru@C) were fabricated by the pyrolysis of Cu-BTC metal-organic frameworks (MOFs). The Cu-Ru@C-0.5 catalyst exhibits a high faradaic efficiency (FE) of 90.4% at -0.6 V (vs RHE) and an ammonia yield rate of 1700.36 µg h-1mgcat.-1 at -0.9 V (vs RHE). Moreover, the nitrate conversion rate is almost 100% over varied pHs (including acid, neutral, and alkaline electrolytes) and different nitrate concentrations. The remarkable performance is attributed to the synergistic effect between Cu and Ru and the excellent conductivity of the carbon substrate. This work will open an exciting avenue to exploring MOF derivatives for ambient ammonia synthesis via selective electrocatalytic nitrate reduction.
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The Electrochemical reduction of nitrate to ammonia (NH3) is a process of great significance to energy utilization and environmental protection. However, it suffers from sluggish multielectron/proton-involved steps involving coupling reactions between different reaction intermediates and active hydrogen species (Hads) produced by water decomposition. In this study, a Ru-doped NiFe-MIL-53 (NiFeRu-MIL-53) supported on Ni foam (NF) has been designed for the nitrate reduction reaction (NO3RR). The NiFeRu-MIL-53 exhibits excellent NO3RR activity with a maximum Faradaic efficiency (FE) of 100% at -0.4 V vs. RHE for NH3 and a maximum NH3 yield of 62.39 mg h-1 cm-2 at -0.7 V vs. RHE in alkaline media. This excellent performance for the NO3RR is attributed to a strong synergistic effect between Ru and reconstructed NiFe(OH)2. Additionally, the doped Ru facilitates water dissociation, leading to an appropriate supply of Hads required for N species hydrogenation during NO3RR, thereby further enhancing its performance. Furthermore, in situ Raman analysis reveals that incorporating Ru facilitates the reconstruction of MOFs and promotes the formation of hydroxide active species during the NO3RR process. This work provides a valuable strategy for designing electrocatalysts to improve the efficiency of the reduction of electrochemical nitrate to ammonia.
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Water fluoride pollution has caused non-negligible harm to the environment and humans, and thus it is crucial to find a suitable treatment technology. In this study, La-Fe@PTA adsorbent was synthesized for the defluoridation of mine water. The results showed that the optimum conditions for defluoridation by La-Fe@PTA were pH close to 7.0, the initial F- concentration of 10 mg/L, the dosage of 0.5 g/L and the adsorption time of 240 min. Compared with SO42â, Clâ, NO3â, Ca2+ and Mg2+, CO32â and HCO3â presented severer inhibition on fluoride uptake by La-Fe@PTA. The adsorption process fits well with the pseudo-second-order kinetic model and Freundlich model, and the maximum adsorption capacity of Langmuir model was 95 mg/g. Fixed-bed adsorption results indicated that fluoride in practical fluorinated mine water could be effectively removed from 3.6 mg/L to less than 1.5 mg/L within 130 bed volume (BV) by using 1.5 g La-Fe@PTA. Furthermore, the adsorbent still had good adsorption capacity after regeneration, which confirms the great application potential of La-Fe@PTA as a fluoride ion adsorbent. The mechanism analysis showed that La-Fe@PTA adsorption of fluorine ions is a physicochemical reaction driven by electrostatic attraction and ion exchange.
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Estruturas Metalorgânicas , Poluentes Químicos da Água , Purificação da Água , Humanos , Fluoretos , Água , Adsorção , Cinética , Concentração de Íons de Hidrogênio , Purificação da Água/métodosRESUMO
Although there are some review papers on carbon capture, utilization and storage (CCUS), hardly any of these reviews are focused on the role of CO2 enhanced oil recovery (EOR) in accelerating carbon neutrality in China. In this review, strategies to achieve carbon neutrality is briefly but critically discussed, followed by a review of CO2-EOR as a promising technology. Especially, data analysis, including the number of publications on China's carbon neutrality, per capita CO2 emissions, China's power generation, and the crude oil production of China's large oilfields, is carried out to make the discussion more comprehensive. Given the large amount of coal consumed in China, the high percent of electricity generated with coal, and the slow penetration of renewables already observed, it seems unlikely that 2060 targets will be met without CCUS. In order to achieve carbon neutrality, both reduction in carbon emissions and increase in carbon sequestration are inevitable. Furthermore, it is concluded that CO2 storage through EOR is likely to have a bright future. However, there are some critical issues to be solved, including the technical issues, leakage and safety issues, cost issues, policy issues, etc. In order to turn CO2-EOR into a reliable and more favorable technology, more research and efforts are needed to solve these issues, including advancing carbon capture technologies, improving storage technologies, developing effective monitoring technologies, deploying government support and incentive policies, etc.
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Dióxido de Carbono , Carbono , Carbono/análise , Dióxido de Carbono/análise , Sequestro de Carbono , China , Carvão Mineral/análise , TecnologiaRESUMO
The electro-peroxone (E-peroxone) process is an emerging electrocatalytic ozonation process that is enabled by in situ producing hydrogen peroxide (H2O2) from cathodic oxygen reduction during ozonation. The in situ-generated H2O2 can then promote ozone (O3) transformation to hydroxyl radicals (â¢OH), and thus enhance the abatement of ozone-refractory pollutants compared to conventional ozonation. In this study, a chemical kinetic model was employed to simulate micropollutant abatement during the E-peroxone treatment of various water matrices (surface water, secondary wastewater effluent, and groundwater). Results show that by following the O3 and â¢OH exposures during the E-peroxone process, the abatement kinetics of a variety of model micropollutants could be well predicted using the model. In addition, the effect of specific ozone doses on micropollutant abatement efficiencies could be quantitatively evaluated using the model. Therefore, the chemical kinetic model can be used to reveal important information for the design and optimization of the treatment time and ozone doses of the E-peroxone process for cost-effective micropollutant abatement in water and wastewater treatment.
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Eletroquímica , Modelos Químicos , Oxirredução , Ozônio/química , Poluentes Químicos da Água/química , Eletroquímica/métodos , Cinética , Água/análise , Água/química , Poluentes Químicos da Água/análiseRESUMO
CONTEXT: Momordica charantia L. (Cucurbitaceae) has long been widely used as a traditional remedy for diabetes mellitus in some countries. However, detailed antidiabetic mechanisms are largely unknown. OBJECTIVES: This study clarified the ameliorating effects of M. charantia ethanol extracts (MCE) on the insulin resistance in type 2 diabetes mellitus (T2DM) rats. MATERIALS AND METHODS: T2DM rat model was established by high-fat diet and streptozotocin (STZ) injection. Diabetic rats were randomized into five groups: the model control group (n = 8) (common diet), the high-fat diet metformin (50 mg/kg/d), and the three-dose MCE (100, 200, and 400 mg/kg/d) groups (n = 8 each). After 8 weeks, the fasting serum glucose, insulin, TNF-α, and IL-6 were measured, and the relevant factors of glucose and insulin were monitored by glycogen dyeing, RT-PCR, and western blot, respectively. RESULTS: The 8-week treatment of 400 mg/kg MCE significantly lowered body weight (330.1 versus 365.9 g), serum glucose (7.41 versus 16.63 mmol/L), insulin (12.06 versus 15.89 mIU/L), TNF-α (52.72 versus 81.83 ng/L), and IL-6 (104.81 versus 135.74 ng/L) in comparison with those of the diabetic control group (p < 0.05). It was the same for skeletal muscle glucose transporter 4 (GLUT-4) protein, and glycogen level, suppressor of cytokine signaling-3 (SOCS-3), c-Jun N-terminal kinase (JNK), and Akt expression at both protein and mRNA levels in liver (p < 0.05). CONCLUSIONS: MCE can ameliorate insulin resistance in T2DM rats. This effect may be related to the regulation of mRNA and protein levels of SOCS-3 and JNK.
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Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Momordica charantia/química , Extratos Vegetais/farmacologia , Animais , Glicemia/efeitos dos fármacos , Dieta Hiperlipídica , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Insulina/sangue , Resistência à Insulina , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Masculino , Extratos Vegetais/administração & dosagem , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estreptozocina , Proteína 3 Supressora da Sinalização de Citocinas/genéticaRESUMO
Gastric cancer is one of the most common malignancies worldwide. Interleukin-1-beta (IL-1ß) is a pro-inflammatory cytokine and potent inhibitor of gastric acid secretion. Some studies provided evidence of the association between IL-1B 31 polymorphism and gastric cancer risk while other studies did not. Therefore, we conducted a comprehensive meta-analysis to reassess the association. A systematic literature search of the PubMed and EMBASE databases identified 37 studies with 6108 cases and 8980 controls for this meta-analysis. The crude odd ratios (ORs) and the 95% confidence intervals (CIs) were calculated to evaluate the strength of the association. Meta-regression was used to determine the major source of heterogeneity across the studies. The pooled analysis did not suggest the significant association of IL-1B 31 C>T polymorphism with gastric cancer risk. Stratified analysis was performed by ethnicity, source of control, genotype method, and indicated a significantly increased gastric cancer risk associated with IL-1B 31T variant in the population-based subgroup (heterozygous model: OR = 1.22, 95% CI = 1.03-1.45). Moreover, stratified analysis by Helicobacter pylori infection status indicated that IL-1B 31 polymorphism increased gastric cancer risk in infection-positive subgroup (homozygous model: OR = 1.35, 95% CI = 1.02-1.78; heterozygous model: OR = 1.31, 95% CI = 1.04-1.66; recessive model: OR = 1.29, 95% CI = 1.04-1.61). The study suggested that IL-1B 31 polymorphism might confer susceptibility to gastric cancer in the presence of H. pylori infection, indicating a gene-environment interaction in gastric carcinogenesis.
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Infecções por Helicobacter/genética , Helicobacter pylori/fisiologia , Interleucina-1beta/genética , Neoplasias Gástricas/genética , Estudos de Casos e Controles , Interação Gene-Ambiente , Estudos de Associação Genética , Predisposição Genética para Doença , Infecções por Helicobacter/microbiologia , Humanos , Polimorfismo de Nucleotídeo Único , Neoplasias Gástricas/microbiologiaRESUMO
RATIONALE: Kawasaki disease (KD) is a vasculitis syndrome of small to medium-sized arteries that has typical clinical characteristics such as fever, rash, cervical lymphadenopathy, conjunctivitis, and mucosal changes. Cardiac manifestations, including coronary artery aneurysms, myocarditis, myocardial infarction, and sudden cardiac death, are the most serious complications observed in KD. On rare occasions, it may accompanied with reduced organ perfusion due to systolic hypotension, a condition known as Kawasaki disease shock syndrome (KDSS). KDSS is a serious complication that can be presented to the emergency department as an initial feature when typical clinical symptoms of KD have not be detected. PATIENT CONCERNS: We report the case of a 12-year-old boy admitted with prolonged fever, bilateral non-purulent conjunctivitis, and signs of shock such as hypotension and tachycardia. Laboratory findings showed elevated inflammatory markers, hypoalbuminemia, and sterile pyuria. He was initially treated with intravenous cefotaxime and vancomycin considering the possible diagnosis of toxic shock syndrome, while the treatment was not effective. Subsequent chest computerized tomography and ultrasound identified pulmonary consolidation and polyserous effusion. Echocardiography revealed mild biatrial dilatation and mild valvular regurgitation with preserved left ventricular function. DIAGNOSIS: After a multidisciplinary consultation, a diagnosis of KDSS was made. INTERVENTIONS: To prevent coronary artery lesions and other severe complications, the patient immediately received immunoglobulin, corticoid, and acetylsalicylic acid. OUTCOMES: Soon afterwards, he showed significant improvement, with the temperature dropped to normal and hypotension corrected about 24 hours post-intravenous immunoglobulin therapy. Polyserous effusions also disappeared before discharge. Follow-up echocardiography revealed normal results. LESSONS: Clinicians should maintain a high index of suspicion for KD and consider pulmonary involvement and polyserous effusions as potential complications. For children with KD, any symptoms pointing to infection should be carefully considered. When there is no etiologic evidence, antibiotics should be used with caution. Our case also highlights the importance of considering KDSS as a differential diagnosis in children presenting with prolonged fever and shock. Early recognition, timely treatment, and close monitoring are key to preventing severe complications and ensuring favorable outcomes in patients with KDSS.
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Síndrome de Linfonodos Mucocutâneos , Choque Séptico , Choque , Humanos , Masculino , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Criança , Diagnóstico Diferencial , Choque Séptico/diagnóstico , Choque Séptico/etiologia , Choque/etiologia , Choque/diagnóstico , EcocardiografiaRESUMO
Medicated bath is the most common spiking method used in the development of matrix reference materials for aquatic products; however, the environmental issues caused by the treatment of waste liquid after medicated bath cannot be ignored. We proposed an environmentally friendly spiking method based on microfluidics, which significantly improved the drug utilization rate without the need for subsequent drug residue treatment. Finely processed minced fish samples were fully mixed with quinolone drugs, and minced fish gel microspheres were prepared by microfluidic technology, utilizing the gel's water-locking function to enhance the drug-loading capacity. The results showed that this method can significantly increase the drug-loading capacity of the matrix (2.33-4.03 times) compared with the traditional spiking methods. In addition, the matrix reference material prepared by this method has good stability, and the drug concentration was adjustable and controllable.
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Traditional spiking methods for preparing matrix reference material of aquatic products is difficult to control the drug content in the matrix, especially one matrix containing multiple drugs. Minced fish is commonly used for the preparation of matrix reference materials in aquatic products, which is a relatively complex matrix with stickiness and difficult handling. Drug loading capacity is a key factor affecting the effectiveness of matrix reference materials. Here, we proposed a new spiking approach to improve the drug loading capacity of seven quinolones based on microfluidics, simultaneously. Fresh grass carp tissue underwent grinding, fine filtration, centrifugation and reconstituted in distilled water to form a liquid sample, which was subsequently mixed with a sodium alginate solution (1â¯%) at a ratio of 1:1.2. The mixed solution was supplemented with seven quinolones of equal concentration, followed by the preparation of uniform fish gel microspheres using microfluidic technology. The results indicated that the recoveries of seven quinolones ranged from 82.54â¯% to 114.17â¯%, demonstrating a significant improvement in the drug loading capacity of these quinolones compared to traditional methods. Moreover, the drug concentration in the matrix can be precisely controlled. A strong linear relationship was observed between the concentration of seven quinolones in the matrix and its initial concentration, which could serve as a reference for the development of other matrix reference materials.
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Microfluídica , Quinolonas , Animais , Quinolonas/química , Microfluídica/métodos , Carpas , Alginatos/química , Peixes , MicroesferasRESUMO
The present study aims to investigate the associations among math self-efficacy, parenting style, and math anxiety in primary school children. The sample comprised 400 participants, aged between 10 and 11 years old, from an elementary school in China. Participants completed three self-reported questionnaires on math anxiety, parenting styles and math self-efficacy. The results revealed that rejection was strongly and positively correlated with math anxiety, while emotional warmth was negatively related to math anxiety. Interestingly, math anxiety was found to be related to rejection, with math self-efficacy playing a mediating role in this relationship. Conversely, math self-efficacy played a mediating role in the relationship between parenting styles and math anxiety, while over protection exhibited no significant correlation with math anxiety. The study also showed that gender differences existed in the level of math anxiety and math self-efficacy, with boys exhibiting lower math anxiety and higher math self-efficacy than girls. These results provide important insights into the development and treatment of math anxiety in primary school children. Specifically, parents and educators should focus on enhancing children's math self-efficacy beliefs, while adopting a parenting style characterized by emotional warmth and low levels of rejection.
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This study investigated the formation of dichloroacetamide (DCAM) and dichloroacetic acid (DCAA) from the abatement of three phenicol antibiotics (PABs, chloramphenicol, thiamphenicol, and florfenicol) during ozonation and post-chlor(am)ination. Results show that the three PABs have a low ozone reactivity (kO3 = 0.11â0.12 M-1 s-1), and therefore are mainly abated through the hydrogen abstraction mechanism by hydroxyl radicals (â¢OH) during ozonation. During PAB degradation, the carboxamide moiety in the parent molecules can be cleaved off by â¢OH attack and thus gives rise to DCAM. The formed DCAM can then be further oxidized by O3 and/or â¢OH to DCAA as a more stable transformation product (TP). When the three PABs were adequately abated (abatement efficiency of â¼82 %â95 %), the molar yields of DCAM and DCAA were determined to be 2.79 %â4.71 % and 32.9 %â37.2 %, respectively. Furthermore, post-chloramination of the ozonation effluents increased the yields of DCAM and DCAA slightly to 4.20 %â6.45 % and 39.0 %â41.1 %, respectively. In comparison, post-chlorination eliminated DCAM in the solutions, but significantly increased DCAA yields to â¼100 % due to the further conversion of DCAM and other ozonation TPs to DCAA by chlorine oxidation. The results of this study indicate that high yields of DCAM and DCAA can be generated from PAB degradation during ozonation, and post-chlorination and post-chloramination will result in very different fates of DCAM and DCAA in the disinfected effluent. The formation and transformation of DCAM and DCAA during PAB degradation need to be taken into account when selecting multi-barrier treatment processes for the treatment of PAB-containing water.
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Ozônio , Poluentes Químicos da Água , Purificação da Água , Antibacterianos , Ácido Dicloroacético , Poluentes Químicos da Água/análise , Halogenação , Purificação da Água/métodos , Desinfecção/métodosRESUMO
Singlet oxygen (1O2) has often been identified by the popularly used quenching method as a more important reactive species (RS) than sulfate radicals (SO4â¢-) and hydroxyl radicals (â¢OH) for pollutant abatement during persulfate-based advanced oxidation processes (PS-AOPs), especially those activated by carbon-based catalysts. However, latest studies have demonstrated that the quenching method actually can often mislead the interpretations of the role of RS for pollutant abatement during AOPs due to various confounding effects caused by adding high-concentration quenchers in the system. To clarify the role of 1O2 in PS-AOPs, this study developed a probe compound-based experimental and kinetic model to quantify the concentrations and exposures of 1O2, SO4â¢-, and â¢OH, as well as their relative contributions to pollutant abatement during a cobalt oxide incorporated carbon nanotubes activated peroxymonosulfate (Co3O4@CNTs/PMS) process. Results show that during the Co3O4@CNTs/PMS process, the exposures and transient concentrations of 1O2 were about 19.6 and 41.3 times higher than those of SO4â¢- and â¢OH, respectively. However, the relative contribution of 1O2 to the abatement of most pollutants tested in this study (e.g., sulfisoxazole, sulfamethoxyprazine, trimethoprim, and metoprolol) is generally negligible (f1O2 ≤ 8%) compared to that of SO4â¢- and â¢OH ( [Formula: see text] = 15%-98% and fâ¢OH = 2%-78%) because of the significantly lower reactivity of 1O2 with these compounds than that of SO4â¢- and â¢OH. Reasons for misidentifying 1O2 as the dominant RS for pollutant abatement by the quenching method were then analyzed based on reaction kinetics principles. The results of this study highlight that while 1O2 can be generated in significant amounts and be present at higher concentrations than SO4â¢- and â¢OH in PS-AOP systems, 1O2 is unlikely to be the dominant RS for the abatement of most pollutants during the PS-AOPs because of its weak and selective oxidation capacity, and caution should be taken when using the quenching method to evaluate the role of RS for pollutant abatement by the PS-AOPs.
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Poluentes Ambientais , Nanotubos de Carbono , Poluentes Químicos da Água , Oxigênio Singlete , Poluentes Químicos da Água/análise , Peróxidos , OxirreduçãoRESUMO
Ion exchange membranes (IEMs) are widely used in water treatment applications such as electrodialysis. However, the exploration of IEMs as effective antibacterial food contact materials (e.g., food packaging membranes) against pathogenic bacteria to ensure food safety has not been reported. Here, we report a simple but effective method to prepare high performance antibacterial membranes via ion exchange coupled with in-situ reduction. The general membrane properties are characterized using SEM, EDS, FTIR, XPS, XRD, DSC, TGA, water uptake, etc. The distribution of silver and copper in the membranes are generally in line with the distribution of sulfur, indicating that the antibacterial ions are introduced into the membranes via ion exchange and are bonded with the sulfonate groups in the membranes. The antibacterial performance is investigated using zone of inhibition tests and continuous bacteria growth inhibition tests. All of the prepared membranes show obvious antibacterial activities compared to the bare cation exchange membranes. The diameters of inhibition zone against Staphylococcus aureus (S. aureus) are all larger than those of Escherichia coli (E. coli), indicating that the prepared membranes are more efficient in inhibiting S. aureus compared to E. coli. Furthermore, the silver-based membrane shows more sustainable antibacterial activities compared to the copper-based membrane. Especially, the results clearly reveal that the silver-based membrane is capable of killing bacteria instead of just inhibiting the growth of bacteria. We have shown for the first time that membranes derived from IEMs have the potential as food contact materials to inhibit the growth of pathogenic bacteria so as to eliminate the risk of bacterial infections and meanwhile delay food spoilage due to bacteria growth.
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Nanopartículas Metálicas , Prata , Antibacterianos/farmacologia , Cobre , Escherichia coli , Troca Iônica , Testes de Sensibilidade Microbiana , Prata/farmacologia , Staphylococcus aureusRESUMO
The study of functional corticomuscular coupling can reflect the interaction between the cerebral cortex and muscle tissue, thereby helping to understand how the brain controls muscle tissue and the effect of muscle movement on brain function. This study proposes a detection model of the coupling strength between the cortex and muscles. The detection model uses an adaptive selector to choose the optimal long short-term memory network, uses this network to extract the features of electroencephalography and electromyography, and finally transforms time characteristics into the frequency domain. The transfer entropy is used to represent the interaction intensity of signals in different frequency bands. Using this model, we analyze the coupling relationship between the cortex and muscles in the three movements of wrist flexion, wrist extension, and clench fist, and compare the model with traditional wavelet coherence analysis and deep canonical correlation analysis. The experimental results show that our model can not only express the bidirectional coupling relationship between different frequency bands but also suppress the possible false coupling that traditional methods may detect. Our research shows that the proposed model has great potential in medical rehabilitation, movement decoding, and other fields.
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Memória de Longo Prazo/fisiologia , Memória de Curto Prazo/fisiologia , Córtex Motor/fisiologia , Movimento/fisiologia , Músculo Esquelético/fisiologia , Análise de Correlação Canônica , Eletroencefalografia , Eletromiografia , Entropia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Modelos Neurológicos , Transtornos dos Movimentos/fisiopatologia , Transtornos dos Movimentos/reabilitaçãoRESUMO
Ion exchange membranes (IEMs) are undergoing prosperous development in recent years. More than 30,000 papers which are indexed by Science Citation Index Expanded (SCIE) have been published on IEMs during the past twenty years (2001-2020). Especially, more than 3000 papers are published in the year of 2020, revealing researchers' great interest in this area. This paper firstly reviews the different types (e.g., cation exchange membrane, anion exchange membrane, proton exchange membrane, bipolar membrane) and electrochemical properties (e.g., permselectivity, electrical resistance/ionic conductivity) of IEMs and the corresponding working principles, followed by membrane synthesis methods, including the common solution casting method. Especially, as a promising future direction, green synthesis is critically discussed. IEMs are extensively applied in various applications, which can be generalized into two big categories, where the water-based category mainly includes electrodialysis, diffusion dialysis and membrane capacitive deionization, while the energy-based category mainly includes reverse electrodialysis, fuel cells, redox flow battery and electrolysis for hydrogen production. These applications are comprehensively discussed in this paper. This review may open new possibilities for the future development of IEMs.
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Membranas Artificiais , Diálise Renal , Cátions , Troca Iônica , ÁguaRESUMO
Electroencephalogram (EEG) and electromyogram (EMG) signals during motion control reflect the interaction between the cortex and muscle. Therefore, dynamic information regarding the cortical-muscle system is of significance for the evaluation of muscle fatigue. We treated the cortex and muscle as a whole system and then applied graph theory and symbolic transfer entropy to establish an effective cortical-muscle network in the beta band (12-30 Hz) and the gamma band (30-45 Hz). Ten healthy volunteers were recruited to participate in the isometric contraction at the level of 30% maximal voluntary contraction. Pre- and post-fatigue EEG and EMG data were recorded. According to the Borg scale, only data with an index greater than 14<19 were selected as fatigue data. The results show that after muscle fatigue: (1) the decrease in the force-generating capacity leads to an increase in STE of the cortical-muscle system; (2) increases of dynamic forces in fatigue leads to a shift from the beta band to gamma band in the activity of the cortical-muscle network; (3) the areas of the frontal and parietal lobes involved in muscle activation within the ipsilateral hemibrain have a compensatory role. Classification based on support vector machine algorithm showed that the accuracy is improved compared to the brain network. These results illustrate the regulation mechanism of the cortical-muscle system during the development of muscle fatigue, and reveal the great potential of the cortical-muscle network in analyzing motor tasks.
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Córtex Cerebral/fisiologia , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto , Ritmo beta , Eletroencefalografia , Eletromiografia , Feminino , Ritmo Gama , Humanos , Contração Isométrica , Masculino , Vias Neurais/fisiologia , Processamento de Sinais Assistido por Computador , Adulto JovemRESUMO
Rapid and highly efficient treatment of acid mine drainage (AMD) is still challenging due to the low pH and high metal concentrations in it. This research focuses on a novel treatment method of AMD using direct contact membrane distillation (DCMD) and photocatalysis to recover water and utilize iron. In the DCMD process without pretreatment, the flux decreased by 93.38%. If pretreated by adding sodium oxalate, scale formation potential was effectively mitigated due to the removal of calcium and complexing of iron. For the treatment of the pretreated AMD (PAMD), 60% of water was recovered in the DCMD process with the flux decrease of 22%. The concentrate obtained from the DCMD process demonstrated high photocatalytic activity in the methylene blue (MB) degradation in an aqueous solution. In addition, the Fe (III)-oxalate complexes in the concentrate were reduced to insoluble Fe (II)-oxalate with visible light irradiation, which could be separated by sedimentation and used as a Fenton catalyst. Hence, this novel method exhibits great advantages on effectively inhibiting DCMD membrane fouling during AMD treatment, producing high-quality distillate with low conductivity, and realizing near zero-discharge of AMD.
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Poluentes Químicos da Água , Purificação da Água , Destilação , Ferro , Membranas Artificiais , Mineração , Água , Poluentes Químicos da Água/análiseRESUMO
BACKGROUND: Emotions play a crucial role in human communication and affect all aspects of human life. However, to date, there have been few studies conducted on how movements under different emotions influence human brain activity and cortico-muscular coupling (CMC). NEW METHODS: In this study, for the first time, electroencephalogram (EEG) and electromyogram physiological electrical signals were used to explore this relationship. We performed frequency domain and nonlinear dynamics analyses on EEG signals and used transfer entropy to explore the CMC associated with the emotion-movement relationship. To study the transmission of information between different brain regions, we also constructed a functional brain network and calculated various network metrics using graph theory. RESULTS: We found that, compared with a neutral emotional state, movements made during happy and sad emotions had increased CMC strength and EEG power and complexity. The functional brain network metrics of these three emotional states were also different. COMPARISON WITH EXISTING METHODS: Much of the emotion-movement relationship research has been based on subjective expression and external performance. Our research method, however, focused on the processing of physiological electrical signals, which contain a wealth of information and can objectively reveal the inner mechanisms of the emotion-movement relationship. CONCLUSIONS: Different emotional states can have a significant influence on human movement. This study presents a detailed introduction to brain activity and CMC.
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Encéfalo , Eletroencefalografia , Eletromiografia , Emoções , Humanos , MovimentoRESUMO
Environment protection and food safety are two critical issues in the world. In this review, a novel approach which integrates statistical study and subjective discussion was adopted to review recent advances on environment and food safety. Firstly, a scientometric-based statistical study was conducted based on 4904 publications collected from the Web of Science Core Collection database. It was found that the research on environment and food safety was growing steadily from 2001 to 2020. Interestingly, the statistical analysis of most-cited papers, titles, abstracts, keywords, and research areas revealed that the research on environment and food safety was diverse and multidisciplinary. In addition to the scientometric study, strategies to protect environment and ensure food safety were critically discussed, followed by a discussion on the emerging research topics, including emerging contaminates (e.g., microplastics), rapid detection of contaminants (e.g., biosensors), and environment friendly food packaging materials (e.g., biodegradable polymers). Finally, current challenges and future research directions were proposed.