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Benefiting from similar hydrogen bonding energy to Pt and much lower price compare with Pt, Ru based catalysts are promising candidates for electrocatalytic hydrogen evolution reaction (HER). The catalytic activity of Ru nanoparticles can be enhanced through improving their dispersion by using different supports, and the strong metal supports interaction can further regulate their catalytic performance. In addition, single-atom catalysts (SACs) with almost 100% atomic utilization attract great attention and the coordinative atmosphere of single atoms can be adjusted by supports. Moreover, the syngenetic effects of nanoparticles and single atoms can further improve the catalytic performance of Ru based catalysts. In this review, the progress of Ru based HER electrocatalysts are summarized according to their existing forms, including nanoparticles (NPs), single atoms (SAs) and the combination of both NPs and SAs. The common supports such as carbon materials, metal oxides, metal phosphides and metal sulfides are classified to clarify the metal supports interaction and coordinative atmosphere of Ru active centers. Especially, the possible catalytic mechanisms and the reasons for the improved catalytic performance are discussed from both experimental results and theoretical calculations. Finally, some challenges and opportunities are prospected to facilitate the development of Ru based catalysts for HER.
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As an important half-reaction for electrochemical water splitting, electrocatalytic hydrogen evolution reaction suffers from sluggish kinetics, and it is still urgent to search high efficiency non-platinum-based electrocatalysts. Mo-based catalysts such as Mo2 C, MoO2 , MoP, MoS2 , and MoNx have emerged as promising alternatives to Pt/C owing to their similar electronic structure with Pt and abundant reserve of Mo. On the other hand, due to the adjustable topology, porosity, and nanostructure of metal organic frameworks (MOFs), MOFs are extensively used as precursors to prepare nano-electrocatalysts. In this review, for the first time, the progress of Mo-MOFs-derived electrocatalysts for hydrogen evolution reaction is summarized. The preparation method, structures, and catalytic performance of the catalysts are illustrated based on the types of the derived electrocatalysts including Mo2 C, MoO2 , MoP, MoS2 , and MoNx . Especially, the commonly used strategies to improve catalytic performance such as heteroatoms doping, constructing heterogeneous structure, and composited with noble metal are discussed. Moreover, the opportunities and challenges in this area are proposed to guide the designment and development of Mo-based MOF derived electrocatalysts.
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The biogenic synthesis of silver nanoparticles (AgNPs) by microorganisms has been a subject of increasing attention. Despite extensive studies on this biosynthetic pathway, the mechanisms underlying the involvement of proteins and enzymes in AgNPs production have not been fully explored. Herein, we reported that Burkholderia contaminans ZCC was able to reduce Ag+ to AgNPs with a diameter of (10±5) nm inside the cell. Exposure of B. contaminans ZCC to Ag+ ions led to significant changes in the functional groups of cellular proteins, with approximately 5.72% of the (C-OH) bonds being converted to (C-C/C-H) (3.61%) and CO (2.11%) bonds, and 4.52% of the CO (carbonyl) bonds being converted to (C-OH) bonds. Furthermore, the presence of Ag+ and AgNPs induced the ability of extracellular electron transfer for ZCC cells via specific membrane proteins, but this did not occur in the absence of Ag+ ions. Proteomic analysis of the proteins and enzymes involved in heavy metal efflux systems, protein secretion system, oxidative phosphorylation, intracellular electron transfer chain, and glutathione metabolism suggests that glutathione S-transferase and ubiquinol-cytochrome c reductase iron-sulfur subunit play importance roles in the biosynthesis of AgNPs. These findings contribute to a deeper understanding of the functions exerted by glutathione S-transferase and ferredoxin-thioredoxin reductase iron-sulfur subunits in the biogenesis of AgNPs, thereby hold immense potential for optimizing biotechnological techniques aimed at enhancing the yield and purity of biosynthetic AgNPs.
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Burkholderia , Nanopartículas Metálicas , Proteoma , Prata , Prata/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Proteoma/metabolismo , Burkholderia/metabolismo , Proteômica , Proteínas de Bactérias/metabolismoRESUMO
Designing electrocatalysts with strong electronic metal-support interaction can effectively regulate the electronic properties of metal active centers, therefore maximizing the catalytic performance. As a proof of concept, heteroatoms doped carbon with CoPt alloy and isolated Co single atoms (CoPtCoSA@NSC) are synthesized using CoPt bimetallic metal-organic framework as the precursor in this work. The existence of CoSA on the carbon substrate leads to more electron transfer between CoPt and the support, and appropriate upward shift of the d band center of the catalysts, which can effectively reduce the reaction barrier of rate determine step and boost the catalytic performance of CoPt alloy. The enhanced catalytic activity and stability of CoPtCoSA@NSC are demonstrated experimentally. Remarkably, the overpotential for hydrogen evolution reaction is only 23 mV at 10 mA cm-2 and the half-wave potential for oxygen reduction reaction is 0.90 V, both exceeding the commercial Pt/C benchmark. In addition, CoPtCoSA@NSC also exhibits great potential as a cathode electrocatalyst for Zn-air battery, in terms of large open circuit potential of 1.53 V, high power density of 184 mW cm-2 , as well as superior cycling stability. This work provides a novel strategy for regulating the electronic structure and catalytic performance of alloy based electrocatalysts.
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Alzheimer's disease (AD) is a progressive and degenerative disorder accompanied by cognitive decline, which could be promoted by mitochondrial dysfunction induced by mitochondrial Ca 2+ (mCa 2+) homeostasis Mitochondrial calcium uniporter (MCU), a key channel of mCa 2+ uptake, may be a target for AD treatment. In the present study, we reveal for the first time that MCU knockdown in hippocampal neurons improves the memory performance of APP/PS1/tau mice through radial arm maze task. Western blot analysis, transmission electron microscopy (TEM), Golgi staining, immunohistochemistry (IHC) and ELISA results demonstrate that MCU knockdown in hippocampal neurons upregulates the levels of postsynaptic density protein 95 (PSD95) and synaptophysin (SYP), and increases the numbers of synapses and dendritic spines. Meanwhile, MCU knockdown in hippocampal neurons decreases the neuroinflammatory response induced by astrogliosis and high levels of IL-1ß and TNF-α, and improves the PINK1-Parkin mitophagy signaling pathway and increases the level of Beclin-1 but decreases the level of P62. In addition, MCU knockdown in hippocampal neurons recovers the average volume and number of mitochondria. These data confirm that MCU knockdown in hippocampal neurons improves the memory performance of APP/PS1/tau mice through ameliorating the synapse structure and function, relieving the inflammation response and recovering mitophagy, indicating that MCU inhibition has the potential to be developed as a novel therapy for AD.
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Doença de Alzheimer , Canais de Cálcio , Memória , Neurônios , Animais , Camundongos , Doença de Alzheimer/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Camundongos Transgênicos , Neurônios/metabolismo , Canais de Cálcio/genéticaRESUMO
Alzheimer's disease (AD) is a neurodegenerative disorder, which seriously affects health of the elderly, and is still irreversible up to now. Recent studies have indicated that mitochondrial dysfunction is a direct reason to promote the development of AD. Mitochondrial calcium uniporter (MCU), located in the inner membrane of mitochondria, is a key channel of mitochondrial Ca2+ uptake. Abnormal MCU expression results in imbalance of mitochondrial calcium homeostasis, ultimately leading to mitochondrial dysfunction. The purpose of this study was to determine the effects of MCU knockdown on AD hippocampal neurons and learning and memory function of AD model mice. Lentivirus and adeno-associated virus were used as vectors to transfect shRNA into hippocampal neurons (HT22 cells) and hippocampi of amyloid precursor protein (APP)/presenilin 1 (PS1)/tau AD transgenic mice, respectively, in order to interfere with MCU expression. The cellular activity of HT22 cells was detected by MTS method, and the changes of learning and memory dysfunction in APP/PS1/tau AD transgenic mice were tested by Y maze and Morris water maze. The results showed that MCU knockdown reversed the cellular activity of HT22 cells decreased by amyloid beta protein 1-42 (Aß1-42) or okadaic acid (OA). Knockdown of MCU in hippocampal neurons improved spontaneous alternation (spatial working memory), decreased escape latency, and increased time in target quadrant and number of platform crossing (spatial reference memory) of the APP/PS1/tau mice. This study suggests that MCU knockdown in hippocampal neurons has anti-AD effect, and it is expected to be a new strategy for prevention and treatment of AD.
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Doença de Alzheimer , Animais , Camundongos , Peptídeos beta-Amiloides/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Neurônios , Camundongos TransgênicosRESUMO
OBJECTIVE: Perineural injection therapy with 5% dextrose water is progressively becoming a mainstream method for treating carpal tunnel syndrome. However, its long-term outcome is still unknown. Hence, the purpose of this retrospective study was to investigate the long-term outcome after perineural injection therapy using 5% dextrose water. METHODS: A total of 185 patients diagnosed with carpel tunnel syndrome at least 1 year post-therapy were enrolled. All the patients underwent ultrasound-guided perineural injection therapy using 10 ml of 5% dextrose water at the outpatient department. In a structured telephone interview, the patients were asked about the outcome post-therapy compared with pre-injection. A symptom relief ≥50% indicated effective outcome, and a symptom relief <50% was indicative of a poor outcome. RESULTS: In total, 88.6% patients reported an effective outcome, and 11.4% rated the outcome as poor, after a mean of 2.2 injections with a mean of 1-3 years' post-injection follow-up. The outcome was significantly related with severity level, and the patients that reported a poor outcome had a significantly higher incidence of severe grade compared with those who reported an effective outcome (52.4% vs 31.7%, P = 0.03). Patients with mild, moderate and severe grades, respectively, required an average of 1.7 (0.1), 2.4 (0.2) and 2.6 (0.3) injections to reach an effective outcome (P = 0.006) (severe vs mild, P = 0.008; moderate vs mild, P = 0.062). CONCLUSION: Perineural injection therapy is a novel approach for treatment of carpal tunnel syndrome with safe and outstanding long-term effects.
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Síndrome do Túnel Carpal , Glucose/administração & dosagem , Injeções/métodos , Síndrome do Túnel Carpal/diagnóstico , Síndrome do Túnel Carpal/tratamento farmacológico , Síndrome do Túnel Carpal/fisiopatologia , China , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados da Assistência ao Paciente , Nervos Periféricos/efeitos dos fármacos , Soluções Farmacêuticas/administração & dosagem , Estudos Retrospectivos , Avaliação de Sintomas/métodos , Tempo , Resultado do TratamentoRESUMO
Background: Perineural injection therapy with 5% dextrose water (D5W) is a potential and innovative treatment with long-term efficacy for carpal tunnel syndrome (CTS). However, the prognostic factors of this management are lacking; hence, the aim of this retrospective study was to identify the prognostic factors of D5W perineural injection therapy for mild-to-moderate CTS. Methods: A total of 52 patients (52 wrists) diagnosed with mild-to-moderate CTS and treated with a single ultrasound-guided 5cc D5W perineural injection were retrospectively reviewed. Patient-reported injection outcomes (visual analog scale, VAS) at 6 months post-injection were categorized into two groups; (1) Good outcome, when symptom relief ≥50% compared to pre-injection and (2) Poor outcome, when symptom relief < 50% compared to pre-injection. Significant variables between groups were entered into a binary logistic regression with forward stepwise regression to determine the prognostic factors for these outcomes. Results: The treatment outcome was significantly related to body height and sensory nerve conduction velocity (SNCV) (159.1 ± 1.0 vs. 155.0 ± 1.8, p=0.04; 33.6 ± 0.8 vs. 28.3 ± 1.2, p=0.001, good vs. poor outcomes). However, only SNCV remained significantly correlated with the outcomes after conducting stepwise logistic regression (ORs: 1.201; 95% CI 1.05-1.38; p=0.01). Conclusions: SNCV was found to be a significant prognostic factor of treatment outcome for patients with mild-to-moderate CTS 6 months after a D5W perineural injection.
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Síndrome do Túnel Carpal/tratamento farmacológico , Glucose/administração & dosagem , Nervo Mediano/efeitos dos fármacos , Dor/tratamento farmacológico , Síndrome do Túnel Carpal/complicações , Síndrome do Túnel Carpal/diagnóstico , Feminino , Seguimentos , Humanos , Injeções/métodos , Masculino , Nervo Mediano/diagnóstico por imagem , Pessoa de Meia-Idade , Dor/diagnóstico , Dor/etiologia , Medição da Dor/estatística & dados numéricos , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Ultrassonografia de IntervençãoRESUMO
Background: This study is to compare the efficacy of short-axis hydrodissection with long-axis hydrodissection for patients with mild-to-moderate carpal tunnel syndrome (CTS). Methods: Forty-seven patients with mild-to-moderate CTS were enrolled in a prospective, randomized, single-blinded, controlled trial (6 months follow-up). With ultrasound guidance, patients in both groups (short-axis or long-axis groups) were injected with normal saline (5 mL per session). Assessments were performed before and 2 weeks after the injection, as well as at 1, 3, and 6 months post-intervention. The primary outcome measure was the Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) score and secondary outcomes included the cross-sectional area of the median nerve and electrophysiological studies. Results: Forty-four patients (21 wrists in the short-axis group and 23 wrists in the long-axis group) completed the study. Compared with the baseline, both groups showed improved BCTQ and cross-sectional area at all follow-up assessments (p<0.05). The short-axis group was not more effective except significant improvements in BCTQ-severity and BCTQ-function 1 month post-injection compared to the long-axis group (p = 0.031 and p = 0.023, respectively). Conclusions: Both short- and long-axis hydrodissection were effective for patients with mild-to-moderate CTS and the short-axis approach was not more effective than long-axis injection. Further studies with larger sample sizes, multiple injections, and larger injection volume are encouraged in the future.
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Síndrome do Túnel Carpal/terapia , Dissecação/métodos , Hidratação/métodos , Nervo Mediano/cirurgia , Bloqueio Nervoso/métodos , Adulto , Idoso , Feminino , Humanos , Injeções , Masculino , Nervo Mediano/fisiopatologia , Pessoa de Meia-Idade , Estudos Prospectivos , Método Simples-Cego , Inquéritos e Questionários , Resultado do TratamentoRESUMO
OBJECTIVE: To assess the therapeutic effect of platelet-rich plasma (PRP) for moderate-to-severe carpal tunnel syndrome (CTS). DESIGN: A prospective, randomized, double-blinded, controlled trial (1-year follow-up). SETTING: Outpatient of local medical center settings. PARTICIPANTS: Patients (N=26) who were diagnosed with bilateral moderate-to-severe CTS (total 52 wrists) were included. For each patient, one wrist was randomized into either the PRP or control group and the contralateral wrist of the same patient was allocated to another group. Twenty-four patients were included in the final data analysis. INTERVENTIONS: The wrists in the PRP group received a single ultrasound-guided dose of PRP injection (3.5mL), and the control group received a single ultrasound-guided injection with normal saline (3.5mL). MAIN OUTCOME MEASURES: The Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) scores were used as the primary outcome. Secondary outcomes encompassed the cross-sectional area of the median nerve and electrophysiological study. Assessments were conducted prior to injection and 1, 3, 6, and 12 months postinjection. RESULTS: Compared to the control group, the PRP group exhibited significant improvements in BCTQ severity scores at all time points, BCTQ functional scores at the sixth month, and cross-sectional area at the 12th month postinjection (P<.0125). CONCLUSIONS: A single dose of ultrasound-guided perineural PRP injection can provide therapeutic effect for 1 year postinjection.
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Síndrome do Túnel Carpal/terapia , Plasma Rico em Plaquetas , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários , Ultrassonografia de IntervençãoRESUMO
It is of increasing importance to develop highly active and economical oxygen reduction reaction (ORR) electrocatalysts, which have great significance for the large-scale implementation of various energy conversion systems, including metal-air batteries and fuel cells. Herein, a novel method to synthesize FeNx -decorated carbon nanotubes as a high-efficiency ORR catalyst, by utilizing ZnO nanowires as a sacrificial template and a Fe-polydopamine complex as metal and carbon sources, is reported. The obtained catalyst shows great potential for replacing Pt/C as the ORR catalyst under various pH conditions, from alkaline to acidic electrolytes. The high conductivity, large surface area of the carbon nanotube, and highly active FeNx species contributed greatly to the high performance of the catalyst. The work presented herein paves a new way for the synthesis of 1D porous nanomaterials for a broad range of energy-related applications.
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INTRODUCTION: In this study we explored the efficacy of nerve hydrodissection for mild-to-moderate carpal tunnel syndrome (CTS). METHODS: Thirty-four participants were randomly assigned to an intervention group or a control group. One 5-ml dose of normal saline was injected into the intracarpal and subcutaneous regions in subjects of both groups, respectively. The primary outcome measure was the Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) score. Secondary outcomes were cross-sectional area of the median nerve and electrophysiological studies. Assessments were performed before the injection and at 1, 2, 3, and 6 months postintervention. RESULTS: Compared with the control group, the intervention group showed significantly greater improvement at the second and third posttreatment months according to BCTQ severity score and at all time-points for cross-sectional area of the median nerve (P < 0.01). DISCUSSION: Our study demonstrates the therapeutic effects of nerve hydrodissection for mild-to-moderate CTS. Muscle Nerve 59:174-180, 2019.
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Síndrome do Túnel Carpal/tratamento farmacológico , Nervo Mediano/efeitos dos fármacos , Nervo Mediano/fisiologia , Solução Salina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Síndrome do Túnel Carpal/diagnóstico por imagem , Estudos Transversais , Método Duplo-Cego , Estimulação Elétrica , Feminino , Humanos , Masculino , Nervo Mediano/diagnóstico por imagem , Pessoa de Meia-Idade , Condução Nervosa/efeitos dos fármacos , Medição da Dor , Estudos Prospectivos , Estatísticas não Paramétricas , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia de Intervenção , Adulto JovemRESUMO
Corporal punishment is believed to precede various forms of violent behavior, yet prior research has yielded inconsistent findings, partly due to variations in violent types and other factors. This meta-analysis systematically reviewed 35 studies including 144 effect sizes (comprising a total sample size of 159,213) investigating the association between corporal punishment and a spectrum of violent behaviors called Violent Behavior Spectrum (VBS). Additionally, meta-regressions were conducted to explore the moderating impact of punishment severity, violence type and cultural context. Our findings indicated a significant positive relationship between corporal punishment and VBS (r = 0.238, 95%, CI [0.176, 0.300]). Notably, punishment severity was found to influence the strength of this association. Namely, The more severe the corporal punishment, the more likely it is to lead to VBS. These results enhance our understanding of the intricate connection between corporal punishment and various forms of violence, providing valuable insights for both parenting practices and policy development.
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The present study conducted a comprehensive meta-analysis to systematically review the relationship between occupational burnout and work pressure among Chinese police officers. Additionally, the study explored the mediating role of coping styles using a meta-analytic structural equation model. The investigation involved a thorough search of CNKI, PubMed, PsychInfo, Web of Science, and Google Scholar databases, resulting in the identification of a total of 39 studies with 124 effect sizes and 14,089 police officers. The findings revealed a positive correlation between work pressure and occupational burnout among Chinese police officers (r = 0.410, 95% CI = [0.347, 0.469]). Furthermore, negative coping styles mediate the relationship between work pressure and occupational burnout. Importantly, these conclusions held true across various work regions for police officers. These results provide insights into the relationship magnitude between work pressure and occupational burnout in Chinese police work and shed light on the underlying mechanisms. Based on these findings, it is recommended that interventions focusing on reducing work pressure and fostering positive coping styles be implemented to mitigate occupational burnout among police officers.
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Adaptação Psicológica , Esgotamento Profissional , Polícia , Humanos , Esgotamento Profissional/psicologia , Esgotamento Profissional/epidemiologia , Polícia/psicologia , Polícia/estatística & dados numéricos , China/epidemiologia , Estresse Ocupacional/psicologia , Estresse Ocupacional/epidemiologia , População do Leste AsiáticoRESUMO
Constructing heterogeneous catalysts can significantly boost the electrocatalytic activity due to the improved intrinsic catalytic activity induced by tailored electronic structure and optimized chemisorption to the reaction intermediates. RuO2 based electrocatalysts are especially attractive due to the high catalytic activity of RuO2. To reduce the usage of noble metal and improve the catalytic activity of catalyst, CoMoO4-RuO2 micro-flower was synthesized using a facile hydrothermal-calcination method in this work. CoMoO4-RuO2 exhibits a low overpotential of 177 mV at 10 mA cm-2 for oxygen evolution reaction (OER) and a high half-wave potential of 0.858 V for oxygen reduction reaction (ORR). Moreover, the Zn-air battery assembled using CoMoO4-RuO2 exhibit shows a high maximum discharge power density of 149 mW cm-2 and a large open circuit voltage of 1.38 V. The good performance can be attributed to the incorporation of RuO2, which not only induces extra catalytic active sites, but also forms heterojunction with CoMoO4 to optimize the electronic structure of CoMoO4-RuO2, thereby achieving a better equilibrium of absorption and desorption of intermediates. The work provides insights into designing RuO2 based electrocatalysts for advanced electrocatalysis.
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Thrombus and cardiovascular diseases pose a significant health threat, and dietary interventions have shown promising potential in reducing the incidence of these diseases. Marine bioactive proteins and peptides have been extensively studied for their antithrombotic properties. They can inhibit platelet activation and aggregation by binding to key receptors on the platelet surface. Additionally, they can competitively anchor to critical enzyme sites, leading to the inhibition of coagulation factors. Marine microorganisms also offer alternative sources for the development of novel fibrinolytic proteins, which can help dissolve blood clots. The advancements in technologies, such as targeted hydrolysis, specific purification, and encapsulation, have provided a solid foundation for the industrialization of bioactive peptides. These techniques enable precise control over the production and delivery of bioactive peptides, enhancing their efficacy and safety. However, it is important to note that further research and clinical studies are needed to fully understand the mechanisms of action and therapeutic potential of marine bioactive proteins and peptides in mitigating thrombotic events. The challenges and future application perspectives of these bioactive peptides also need to be explored.
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Doenças Cardiovasculares , Trombose , Humanos , Doenças Cardiovasculares/prevenção & controle , Peptídeos/farmacologia , Peptídeos/química , Anticoagulantes/química , Plaquetas , Trombose/prevenção & controle , Trombose/tratamento farmacológicoRESUMO
Developing high-active and inexpensive electrocatalysts for oxygen evolution reaction (OER) is very important in the field of water splitting. The catalytic performance of electrocatalysts can be significantly improved by optimizing the electronic structure and designing suitable nanostructure. In this work, we represent the synthesis of hollow CoVOx/Ag-5 for OER. Due to the interaction of CoVOx and Ag nanoparticles, the electronic structure is optimized to improve the intrinsic catalytic activity. Additionally, the extrinsic catalytic activity of CoVOx/Ag is enhanced by the abundant active sites from the hollow structure. As a result, the CoVOx/Ag-5 demonstrates significantly enhanced OER catalytic activity with a low overpotential of 247 mV at 10 mA cm-2. In addition, it also exhibits excellent durability, without obvious attenuation in performance after continuous operation for 60 h. Furthermore, the catalyst can enable full water splitting with appropriate 100 % Faraday efficiency, demonstrating its practical application.
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In this work, an electric field-enhanced heterogeneous catalytic ozonation (EHCO) was systematically investigated using a prepared FeOx/PAC catalyst. The EHCO process exhibited high sulfadiazine (SDZ) and TOC removal efficiency compared with electrocatalysis (EC) and heterogeneous catalytic ozonation (HCO) process. Almost 100% of SDZ was removed within 2 min, and the TOC removal reached approximately 85% within 60 min. Quenching experiments and EPR analysis suggested that the prominent SDZ and TOC removal performance is supported by the enhanced ·OH generation ability. Further study proved that H2O2 formed by O2 electrochemical reduction, peroxone reaction and electrochemical reduction of ozone contributed to improving ·OH generation. Furthermore, the EHCO system showed satisfactory stability and recyclability compared to conventional HCO systems, and the SDZ and TOC removal rates were maintained at ≥95% and ≥70% in 16 consecutive recycles, respectively. Meanwhile, XPS analysis and Boehm's titration for the FeOx/PAC catalyst used in HCO and EHCO process confirmed that the external electron supply could restrain the oxidation of surface functional groups of PAC and maintain a balance of the Fe(II)/Fe(III) ratio, which proved the critical role of cathode reduction in catalyst in situ regeneration during long consecutive recycles. In addition, the EHCO system could achieve more than 80% SDZ removal within 2 min in different water matrices. These results confirmed that the EHCO process has a wide application perspective for refractory organics removal in actual wastewater.
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Ozônio , Poluentes Químicos da Água , Purificação da Água , Peróxido de Hidrogênio , Compostos Férricos , Sulfadiazina/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Ozônio/análise , CatáliseRESUMO
In this study, we purified a partially acetylated heteropolysaccharide (Ts1-1A) from the fruit bodies of Trametes sanguinea Lloyd through cold water extraction and serial chromatographic separation. The purified polysaccharide Ts1-1A (12.8 kDa) was characterized as a branched mannogalactofucan with a backbone of alternately connected 1,3-linked α-Fucp and 1,6-linked α-Galp, which was partially substituted by non-reducing end units of ß-Manp at O-2 and O-3 positions of 1,6-linked α-Galp. Ts1-1A showed pronounced anti-human cytomegalovirus activity at the concentration of 200 and 500 µg/mL in systematical assessments including morphological changes, western blotting, qPCR, indirect immunofluorescence and tissue culture infective dose assays. Moreover, Ts1-1A exerted its antiviral activity at two distinct stages of viral proliferation manifesting as significantly inhibiting viral protein (IE1/2 and p52) expression and reducing viral gene (UL123, UL44 and UL32) replication in the HCMV-infected WI-38 cells. At viral attachment stage, Ts1-1A interacted with HCMV and prevented HCMV from attaching to its host cells. While at early phase of viral replication stage, Ts1-1A suppressed HCMV replication by downregulating NQO1 and HO-1 proteins related to oxidative stress as an antioxidant. To sum up, Ts1-1A is a promising anti-HCMV agent which could be developed for HCMV infection prevention and therapy.