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1.
J Environ Sci (China) ; 146: 217-225, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38969449

RESUMO

Membrane fouling is a bottleneck issue that hindered the further application of ultrafiltration technology. To alleviate membrane fouling, coagulation-ultrafiltration (C-UF) process using polyaluminum chloride (PACl) and PACl-Al13 with high proportion of Al13O4(OH)247+ as coagulants, respectively, were investigated at various pH conditions. Results indicated that an increase in solution pH contributed to larger floc size and looser floc structure for both PACl and PACl-Al13. It was conducive to the formation of more porous cake, as evidenced by mean pore area and pore area distribution of cake, leading to lower reversible fouling. Furthermore, humic acid (HA) removal presented a trend of first increasing and then decreasing with the increase of pH. The optimal HA removal was achieved at pH 6 regardless of coagulant type, suggesting that the slightest irreversible fouling should be occurred at this point. Interestingly, the irreversible fouling with PACl coagulant achieved a minimum value at pH 9, while the minimal irreversible fouling with PACl-Al13 was observed at pH 6. We speculated that the cake formed by PACl could further intercept HA prior to UF process at alkaline pH. Furthermore, compared with PACl, PACl-Al13 had a stronger charge neutralization ability, thus contributing to more compact floc structure and higher HA removal at various pH conditions. By UF fractionation measurement, higher HA removal for PACl-Al13 was due to higher removal of HA with molecular weight less than 50 kDa.


Assuntos
Substâncias Húmicas , Membranas Artificiais , Ultrafiltração , Ultrafiltração/métodos , Substâncias Húmicas/análise , Floculação , Hidróxido de Alumínio/química , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Eliminação de Resíduos Líquidos/métodos
2.
BMC Anesthesiol ; 24(1): 218, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956515

RESUMO

BACKGROUND: As a new type of intravenous anesthetic, ciprofol has the advantages of fast onset of action, fast recovery and high clearance rate. This study aimed to investigate the effectiveness and safety of ciprofol versus traditional propofol for anesthesia and sedation in and out of the operating room. METHODS: We searched the literature in PubMed, Web of Science, Cochrane Library, and Embase databases from January 2021 to December 2023. All clinical studies comparing the sedative effects of propofol and ciprofol, both inside and outside the operating room, were included in our trial. The main outcome measures were induction time and incidence of injection-site pain. Data are merged using risk ratio and standardized mean difference with 95% confidence interval. Subgroup analysis, meta-regression, sensitivity analysis, and publication bias were performed. The study protocol was prospectively registered with PROSPERO (CRD42023447747). RESULTS: A total of 15 randomized, controlled trials involving 2002 patients were included in this study. Compared with propofol, ciprofol has a longer induction time in the operating room but a shorter induction time in non-operating room settings. Ciprofol can effectively reduce the risk of injection-site pain and respiratory depression both inside and outside the operating room. In addition, the risk of drug-related hypotension induced with ciprofol in the operating room is lower, but the awakening time is also longer. Meta-regression analysis showed that neither age nor BMI were potential sources of heterogeneity. Funnel plot, egger and begg tests showed no significant publication bias. Sensitivity analyzes indicate that our results are robust and reliable. CONCLUSION: Ciprofol has absolute advantages in reducing the risk of injection-site pain and respiratory depression, both in and outside operating room. Intraoperative use of ciprofol reduces the risk of drug-related hypotension and may also reduce the risk of intraoperative physical movements. However, ciprofol may have longer induction and awakening time than propofol.


Assuntos
Anestésicos Intravenosos , Salas Cirúrgicas , Propofol , Propofol/efeitos adversos , Propofol/administração & dosagem , Humanos , Anestésicos Intravenosos/efeitos adversos , Anestésicos Intravenosos/administração & dosagem , Hipnóticos e Sedativos/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos
3.
Adv Mater ; : e2404689, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748686

RESUMO

Revitalizing metal anodes for rechargeable batteries confronts challenges such as dendrite formation, limited cyclicity, and suboptimal energy density. Despite various efforts, a practical fabrication method for dendrite-free metal anodes remains unavailable. Herein, focusing on Li as exemplar, a general strategy is reported to enhance reversibility of the metal anodes by forming alloyed metals, which is achieved by induction heating of 3D substrate, lithiophilic metals, and Li within tens of seconds. It is demonstrated that preferred alloying interactions between substrates and lithiophilic metals created a lithiophilic metal-rich region adjacent to the substrate, serving as ultrastable lithiophilic host to guide dendrite-free deposition, particularly during prolonged high-capacity cycling. Simultaneously, an alloying between lithiophilic metals and Li creates a Li-rich region adjacent to electrolyte that reduces nucleation overpotential and constitutes favorable electrolyte-Li interface. The resultant composite Li anodes paired with high areal loading LiNi0.8Co0.1Mn0.1O2 cathodes achieve superior cycling stability and remarkable energy density above 1200 Wh L-1 (excluding packaging). Furthermore, this approach shows broader applicability to other metal anodes plagued by dendrite-related challenges, such as Na and Zn. Overall, this work paves the way for development of commercially viable metal-based batteries that offer a combination of safety, high energy density, and durability.

4.
Ann Med ; 56(1): 2357354, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38813815

RESUMO

BACKGROUND: Early diagnosis of acute gallstone pancreatitis severity (GSP) is challenging in clinical practice. We aimed to investigate the efficacy of CT features and radiomics for the early prediction of acute GSP severity. METHODS: We retrospectively recruited GSP patients who underwent CT imaging within 48 h of admission from tertiary referral centre. Radiomics and CT features were extracted from CT scans. The clinical and CT features were selected by the random forest algorithm to develop the ML GSP model for the identification of severity of GSP (mild or severe), and its predictive efficacy was compared with radiomics model. The predictive performance was assessed by the area under operating characteristic curve. Calibration curve and decision curve analysis were performed to demonstrate the classification performance and clinical efficacy. Furthermore, we built a web-based open access GSP severity calculator. The study was registered with ClinicalTrials.gov (NCT05498961). RESULTS: A total of 301 patients were enrolled. They were randomly assigned into the training (n = 210) and validation (n = 91) cohorts at a ratio of 7:3. The random forest algorithm identified the level of calcium ions, WBC count, urea level, combined cholecystitis, gallbladder wall thickening, gallstones, and hydrothorax as the seven predictive factors for severity of GSP. In the validation cohort, the areas under the curve for the radiomics model and ML GSP model were 0.841 (0.757-0.926) and 0.914 (0.851-0.978), respectively. The calibration plot shows that the ML GSP model has good consistency between the prediction probability and the observation probability. Decision curve analysis showed that the ML GSP model had high clinical utility. CONCLUSIONS: We built the ML GSP model based on clinical and CT image features and distributed it as a free web-based calculator. Our results indicated that the ML GSP model is useful for predicting the severity of GSP.


ML GSP model based on machine learning has good severity discrimination in both training and validation cohorts (0.916 (0.872­0.958), 0.914 (0.851­0.978), respectively).We built an online user-friendly platform for the ML GSP model to help clinicians better identify the severity of GSP.


Assuntos
Cálculos Biliares , Aprendizado de Máquina , Pancreatite , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Humanos , Pancreatite/diagnóstico por imagem , Pancreatite/diagnóstico , Feminino , Cálculos Biliares/diagnóstico por imagem , Cálculos Biliares/complicações , Masculino , Tomografia Computadorizada por Raios X/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Idoso , Doença Aguda , Valor Preditivo dos Testes , Diagnóstico Precoce , Algoritmos , Curva ROC
5.
Environ Sci Ecotechnol ; 21: 100416, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38584706

RESUMO

Water reuse is an effective way to solve the issues of current wastewater increments and water resource scarcity. Ultrafiltration, a promising method for water reuse, has the characteristics of low energy consumption, easy operation, and high adaptability to coupling with other water treatment processes. However, emerging organic contaminants (EOCs) in municipal wastewater cannot be effectively intercepted by ultrafiltration, which poses significant challenges to the effluent quality and sustainability of ultrafiltration process. Here, we develop a cobalt single-atom catalyst-tailored ceramic membrane (Co1-NCNT-CM) in conjunction with an activated peroxymonosulfate (PMS) system, achieving excellent EOCs degradation and anti-fouling performance. An interfacial reaction mechanism effectively mitigates membrane fouling through a repulsive interaction with natural organic matter. The generation of singlet oxygen at the Co-N3-C active sites through a catalytic pathway (PMS→PMS∗→OH∗→O∗→OO∗→1O2) exhibits selective oxidation of phenols and sulfonamides, achieving >90% removal rates. Our findings elucidate a multi-layered functional architecture within the Co1-NCNT-CM/PMS system, responsible for its superior performance in organic decontamination and membrane maintenance during secondary effluent treatment. It highlights the power of integrating Co1-NCNT-CM/PMS systems in advanced wastewater treatment frameworks, specifically for targeted EOCs removal, heralding a new direction for sustainable water management.

6.
Adv Mater ; 36(15): e2310051, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38145580

RESUMO

Sodium-ion batteries (SIBs) hold great promise for next-generation grid-scale energy storage. However, the highly instable electrolyte/electrode interphases threaten the long-term cycling of high-energy SIBs. In particular, the instable cathode electrolyte interphase (CEI) at high voltage causes persistent electrolyte decomposition, transition metal dissolution, and fast capacity fade. Here, this work proposes a balanced principle for the molecular design of SIB electrolytes that enables an ultra-thin, homogeneous, and robust CEI layer by coupling an intrinsically oxidation-stable succinonitrile solvent with moderately solvating carbonates. The proposed electrolyte not only shows limited anodic decomposition thus leading to a thin CEI, but also suppresses dissolution of CEI components at high voltage. Consequently, the tamed electrolyte/electrode interphases enable extremely stable cycling of Na3V2O2(PO4)2F (NVOPF) cathodes with outstanding capacity retention (>90%) over 3000 cycles (8 months) at 1 C with a high charging voltage of 4.3 V. Further, the NVOPF||hard carbon full cell shows stable cycling over 500 cycles at 1 C with a high average Coulombic efficiency (CE) of 99.6%. The electrolyte also endows high-voltage operation of SIBs with great temperature adaptability from -25 to 60 °C, shedding light on the essence of fundamental electrolyte design for SIBs operating under harsh conditions.

7.
PeerJ ; 11: e15641, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37397007

RESUMO

Background: MicroRNA-154-5p (miR-154-5p) plays a role in tumorigenesis in diverse human malignancies. Nevertheless, little is known about the mechanism by which miR-154-5p alters the growth and metastasis of cervical cancer. This research aimed to analyze the role of miR-154-5p in the pathology of cervical cancer in vitro and in vivo. Methods: The level of miR-154-5p in human papillomavirus 16 positive cervical cancer cells was examined by real-time quantitative polymerase chain reaction. Bioinformatics predicted the downstream targets and potential functions of miR-154-5p. Furthermore, lentiviral technology was used to construct SiHa cell lines with stable up- and down-expression levels of miR-154-5p. Its differential expression effects on the progress and metastasis of cervical cancer were analyzed using cell culture and animal models. Results: MiR-154-5p showed low expression in cervical cancer cells. Overexpression of miR-154-5p could markedly inhibit the proliferation, migration, and colony formation ability of SiHa cells, concomitantly leading to G1 arrest of the cell cycle, while silencing miR-154-5p triggered the opposite results. Meanwhile, overexpression of miR-154-5p restrained the growth and metastasis of cervical cancer by silencing CUL2 in vivo. Additionally, miR-154-5p reduced CUL2 level, and overexpression of CUL2 influenced the effect of miR-154-5p in cervical cancer. In conclusion, miR-154-5p restrained the growth and metastasis of cervical cancer by directly silencing CUL2.


Assuntos
Proteínas Culina , MicroRNAs , Neoplasias do Colo do Útero , Animais , Feminino , Humanos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , MicroRNAs/genética , Neoplasias do Colo do Útero/genética , Proteínas Culina/genética , Inativação Gênica , Metástase Neoplásica
8.
Sci Total Environ ; 895: 165168, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37379911

RESUMO

In this research, the effects of combined powdered activated carbon (PAC)-ozone (O3) pretreatment on ultrafiltration (UF) performance were comprehensively examined and compared with the conventional O3-PAC pretreatment. The performance of pretreatments on mitigating membrane fouling caused by Songhua River water (SHR) was evaluated by specific flux, membrane fouling resistance distribution, and membrane fouling index. Moreover, the degradation of natural organic matter in SHR was investigated by UV absorbance at 254 nm (UV254), dissolved organic carbon (DOC), and fluorescent organic matter. Results showed that the 100PAC-5O3 process was the most effective in improving the specific flux, with 82.89 % and 58.17 % reductions in the reversible fouling resistance and irreversible fouling resistance respectively. Additionally, the irreversible membrane fouling index was reduced by 20 % relative to 5O3-100PAC. The PAC-O3 process also exhibited superior performance in the degradation of UV254, DOC, three fluorescent components, and three micropollutants in the SHR system compared to O3-PAC pretreatment. The O3 stage played a major role in mitigating membrane fouling, while PAC pretreatment enhanced the oxidation in the subsequent O3 stage during the PAC-O3 process. Furthermore, the Extended Derjaguin-Landau-Verwey-Overbeek theory and pore blocking-cake layer filtration model fitting analysis were employed to explain the mechanisms of membrane fouling mitigation and fouling patterns transformation. It was found that PAC-O3 significantly increased the repulsive interactions between the foulants and the membrane, which restrained the formation of the cake layer filtration stage. Overall, this study evidenced the potential of PAC-O3 pretreatment in surface water treatment applications, providing new insights into the mechanism of controlling membrane fouling and improving the permeate quality.

9.
Front Neurol ; 14: 1156473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37265467

RESUMO

Objective: Telerehabilitation and telemedicine have gradually gained popularity. In 2019, the outbreak of COVID-19 started in Wuhan and then spread across the world. To date, most countries have opted to coexist with the virus. However, patients, especially those who have suffered a stroke, should take measures to avoid being infected with any disease as much as possible since any infectious disease can lead to adverse events for them. Telerehabilitation can be beneficial to stroke patients as they are less likely to be infected by the virus. In recent years, several studies on telerehabilitation have been conducted globally. This meta-analysis aimed to investigate the effects of telerehabilitation on the balance ability of stroke patients, compare the efficacy of conventional rehabilitation with telerehabilitation, explore the characteristics of telerehabilitation and conventional rehabilitation, and provide recommendations for rehabilitation programs in the context of the global pandemic. Methods: We searched Pubmed, Embase, the Web of Science, and The Cochrane Library databases from 1 January 2020 to 31 December 2022 for randomized controlled trials published in English that evaluated the improvement of balance function in stroke patients after telerehabilitation and compared the differences between telerehabilitation (TR) and conventional rehabilitation (CR). The random-effects model was utilized to calculate mean differences (MDs) with 95% confidence intervals (CIs) to estimate intervention effects. Statistical heterogeneity was assessed according to the I2 values. The risk of bias was measured using the Cochrane risk-of-bias assessment tool. Results: We included nine studies in the system evaluation, all of which were included in the pooled analysis. All outcomes in the experimental and control groups improved over time. The comparison between groups concluded that people who received the telerehabilitation intervention had a significant improvement in the Berg Balance Scale (MD = 2.80; 95% CI 0.61, 4.98, P < 0.05, I2 = 51.90%) and the Fugl-Meyer Assessment (MD = 8.12; 95% CI 6.35, 9.88, P < 0.05, I2 = 0) compared to controls. The Timed Up and Go test (MD = -4.59; 95% CI -5.93, -.25, P < 0.05, I2 = 0) and Tinetti Performance-Oriented Mobility Assessment-Balance (MD = 2.50; 95% CI 0.39, 4.61, P < 0.05) scored better in the control group than in the experimental group. There were no significant differences in other outcomes between the two groups. Conclusion: Studies on changes in medical conditions during the COVID-19 pandemic also demonstrated that, for stroke patients, telerehabilitation achieves similar effects as the conventional rehabilitation model and can act as a continuation of the conventional rehabilitation model. Owing to the different equipment and intervention programs of telerehabilitation, its curative effect on the static balance and reactive balance of stroke patients may be different. Currently, telerehabilitation may be more conducive to the rehabilitation of patients' static balance abilities, while conventional rehabilitation is more effective for the rehabilitation of patients' reactive balance. Therefore, further studies are needed for investigating the difference in efficacy between varied devices and telerehabilitation programs. Further research is needed on static and reactive balance. In addition, such research should have a large body of literature and a large sample size to support more definitive findings based on the context of the COVID-19 pandemic. Systematic review registration: CRD42023389456.

10.
JMIR Form Res ; 7: e43175, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36592426

RESUMO

BACKGROUND: Compared with combustible cigarettes, electronic cigarettes (e-cigarettes) can deliver a sufficient amount of nicotine with a significantly reduced emission of toxicants, which renders them as potential harm reduction candidates for tobacco and smoking replacement. However, the use of e-cigarettes is not harm free and the long-term health effect of using e-cigarettes is yet to be established. Given the high prevalence of e-cigarette use across the globe and its potential health concerns, it is imperative to conduct actual use behavior assessments to better understand how e-cigarettes are being consumed in real-world conditions. However, with the currently available technologies, there is still a lack of noninvasive, noninterventional, and convenient instruments for the real-time and real-world use behavior monitoring of e-cigarette product use. Novel technology-based systems that do not primarily rely on self-report or intrusive measurements to monitor e-cigarette use behaviors are therefore highly desired. OBJECTIVE: The primary goal of this study is to investigate the e-cigarette actual use behaviors in the real world via a novel puff recording electronic nicotine delivery system (PR-ENDS). Specifically, we aim to analyze and summarize the survey and PR-ENDS use data and to study the relationships and effects of different factors on these variables. METHODS: In real-world conditions, 61 enrolled UK e-cigarette users were instructed to use PR-ENDS as the primary source of nicotine with their selected e-liquids for at least 3 weeks (21 days). A baseline survey was conducted to collect information about participants' demographics and nicotine use history (cigarette and ENDS). The puff data (ie, puff number, puff duration for each puff, device power, e-liquid nicotine concentrations) were directly recorded by PR-ENDS and uploaded to the cloud for further analyses. The nicotine emission and nicotine consumption were estimated based on recorded puff data. RESULTS: Middle-aged adults with a nicotine history represented the major user profile during the PR-ENDS trial. A wide range of device power and e-liquid nicotine concentrations was applied and their combinations during actual use were found to be rather complex. Various puff parameters (ie, puff duration, puff number, nicotine emission) were assessed with contributing factors from device, e-liquid, and user nicotine history in different effect sizes. The real-time observation revealed substantial intra- and interindividual variabilities in PR-ENDS use behaviors. The use pattern of a quick adaptation followed by consistent product use was recognized for at least 3 weeks during actual use. CONCLUSIONS: The actual use behavior assessment of PR-ENDS was conducted as a proof-of-concept application. The complex interactions of product attributes and significant intra- and interindividual variabilities in e-cigarette use behaviors provided new insights of compensatory behavior, which can inspire future studies in the field of nicotine addiction and abuse liability behavior assessment.

11.
JMIR Form Res ; 7: e42544, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36542679

RESUMO

BACKGROUND: Assessing the naturalistic puff topography and associated nicotine consumption during e-cigarette use is important as such information will not only unveil how these products are being consumed in real-world conditions, but also enable investigators and regulatory bodies to conduct quantitative, accurate, and realistic harmful exposure and nicotine abuse liability risk assessments based on actual e-cigarette use. Conventional approaches cannot accurately, conveniently, and noninvasively determine e-cigarette puff topography in a natural use environment. Thus, novel technology-enabled systems that do not primarily rely on self-report mechanisms or intrusive measurements to monitor e-cigarette product use behaviors are highly desired. OBJECTIVE: This study aimed to explore and demonstrate the feasibility of a novel puff recording electronic nicotine delivery system (PR-ENDS) device for measuring naturalistic puff topography and estimating nicotine consumption during the ad libitum use of products among smokers and vapers. METHODS: An ancillary data analysis based on a completed parent study was conducted. The parent study was a 1-way randomized controlled open-label puff topography and nicotine pharmacokinetic assessment carried out in 24 healthy adults (12 smokers and 12 vapers). Participants were assigned a randomized product use sequence of a PR-ENDS device within 5 site visits for both controlled and ad libitum product use sessions. Blood samples were obtained for plasma nicotine analysis, and questionnaires were administered at various time points. During the ad libitum use session, puff topography was measured using a Clinical Research Support System (CReSS) device as a benchmark, as well as the PR-ENDS device with a built-in puff recording feature. RESULTS: There were no significant differences in representative puff topography parameters (number of puffs, total puff duration, and average puff duration) between the PR-ENDS and CReSS devices at the populational level across different device powers, e-liquid nicotine strengths, and flavors. The nicotine consumption estimated by the PR-ENDS device suggested that this device can be employed as a convenient monitoring tool for estimating nicotine use without measuring e-liquid weight loss between puffs. The linear relationship between nicotine consumption estimated by the PR-ENDS device and the pharmacokinetic parameter AUCad lib (plasma concentration-time curve for 1-hour ad libitum use) substantiated the potential of using this device as a pragmatic, noninvasive, and convenient means for estimating nicotine intake in the human body without blood collection. CONCLUSIONS: The novel PR-ENDS device was feasible for assessing naturalistic puff topography and estimating nicotine consumption and intake in the human body during ad libitum use. Several key factors can influence users' puff topography, including device power levels, e-liquid nicotine strengths, and flavors. The study results pave the way for further research in the real-time measurement of naturalistic puff topography and puffing behaviors in the real world.

12.
Water Res ; 226: 119219, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36242937

RESUMO

Membrane-based technology has been confirmed as an effective way to treat emulsified oily wastewater, however, membrane fouling is still one of practical challenges in long-term operation. Herein, a novel passive-active combined strategy was proposed to control membrane fouling in continuous oily wastewater purification, where the δ-MnO2 decoration layer helped to reduce the total fouling ratio (passive strategy for fouling mitigation) and the catalytic cleaning effectively removed the irreversible oil fouling (active strategy for fouling removal). The functional membrane was prepared via in-situ modification, referred to as δ-MnO2@TA-PES. The morphology, crystalline phase, chemical structure and surface properties of the membranes were systematically characterized. Compared with PES, the δ-MnO2@TA-PES possessed superhydrophilicity, enhanced electronegativity and narrowed pore size. The δ-MnO2@TA-PES achieved high water permeation flux of 723.9 L·m - 2·h - 1·bar-1, excellent oil rejection with separation efficiency above 98.5% for various emulsions, and durable anti-oil-fouling performance with FRRb of 98.0%. Notably, the oil cake layer fouling on δ-MnO2@TA-PES was greatly alleviated owing to its enhanced surface properties. In addition, δ-MnO2@TA-PES showed high cleaning efficiency in the peroxymonosulfate (PMS) cleaning process, where the radical and nonradical pathways occurred simultaneously. And the active substances generated in the nonradical process (especially 1O2) were considered as the main contributor to the reduction of irreversible fouling. Overall, the novel strategy of fouling control ensured the efficient operation of ultrafiltration membranes for the continuous oily wastewater purification.


Assuntos
Ultrafiltração , Purificação da Água , Compostos de Manganês , Membranas Artificiais , Óxidos , Óleos/química
13.
Chemosphere ; 297: 134066, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35202663

RESUMO

In this study, a permanganate-assisted electrocoagulation-ultrafiltration (PEC-UF) process was proposed to control membrane fouling in the treatment of secondary effluent. Four comparable systems, i.e., UF, electro-UF (E-UF), electrocoagulation-UF (EC-UF), and PEC-UF, were investigated to systematically clarify the role of permanganate and electrocoagulation in mitigating membrane fouling. Results revealed that the formation of a dense cake layer containing concentrated solutes was the primary reason for membrane fouling. Electrocoagulation significantly mitigated membrane fouling and resulted in the reduction of the normalized transmembrane pressure of the EC-UF and PEC-UF systems by 35.0% and 44.6% compared with the UF control system, respectively. However, the retention of a considerable amount of iron oxyhydroxide precipitates on the membrane surface aggravated inorganic fouling in the in-situ EC-UF system. Furthermore, the enhanced formation of Fe(III) by oxidation of Fe(II) with permanganate promoted the coagulation process. Hence, increased generation of Fe(III) and enhanced coagulation promoted by formed MnOx accelerated the formation of a hydrophilic cake layer with high porosity and thereby reduced the occurrence of both organic and inorganic membrane fouling. These results demonstrated the potential application of permanganate-assisted in-situ electrical-based methods to control UF membrane fouling during advanced wastewater treatment.


Assuntos
Ultrafiltração , Purificação da Água , Compostos Férricos , Compostos de Manganês , Membranas Artificiais , Óxidos , Purificação da Água/métodos
15.
Water Res ; 209: 117960, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34923440

RESUMO

The synthesized catalyst nitrogen-doped multi-walled carbon nanotubes (N-MWCNTs) were introduced into membrane technology for peroxymonosulfate (PMS) activation. The enhanced permeability of the N-MWCNTs-modified membrane might be attributed to the increase in hydrophilicity and membrane porosity. The catalytic degradation and membrane filtration performance for the N-MWCNTs-modified membrane/PMS system in treating different types of natural waters were evaluated. The removal of phenol by the N-MWCNTs-modified membrane was 83.67% in 2 min, which was greater than the phenol removal by the virgin membrane (3.39%) and N-MWCNT powder (41.42%), respectively. Moreover, the resultant membrane coupled with PMS activation exhibited outstanding removal effects on the fluorescent organics in the secondary effluent and Songhua River water. The combination effectively reduced the total membrane fouling caused by the secondary effluent, Songhua River water, and three typical model organics by 28.19-61.98%. Electron paramagnetic resonance and classical quenching tests presented that the active species (SO4·-, ·OH, and 1O2) and other non-radical processes generated by N-MWCNTs activated PMS decreased the foulants deposition on the membrane surface. Meanwhile, the membrane interception accelerated the aggregation of pollutants and PMS towards the membrane surface through applied pressure, facilitating their mass transfer to the N-MWCNTs surface for the catalysis exerted more effectively. This study demonstrated the potential application of the coupling of N-MWCNTs catalytic oxidation and the UF, which offers a promising prospect to improve the permeate quality and simultaneously overcome the membrane fouling barriers.

16.
Acta Bioeng Biomech ; 23(1): 95-105, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34846033

RESUMO

PURPOSE: The goal of this study was to evaluate the biomechanical effects such as sonoporation or permeability, produced by ultrasound- driven microbubbles (UDM) within microvessels with various parameters. METHODS: In this study, a bubble-fluid-solid coupling system was established through combination of finite element method. The stress, strain and permeability of the vessel wall were theoretically simulated for different ultrasound frequencies, vessel radius and vessel thickness. RESULTS: the bubble oscillation induces the vessel wall dilation and invagination under a pressure of 0.1 MPa. The stress distribution over the microvessel wall was heterogeneous and the maximum value of the midpoint on the inner vessel wall could reach 0.7 MPa as a frequency ranges from 1 to 3 MHz, and a vessel radius and an initial microbubble radius fall within the range of 3.5-13 µm and 1-4 µm, respectively. With the same conditions, the maximum shear stress was equal to 1.2 kPa and occurred at a distance of ±5 µm from the midpoint of 10 µm and the maximum value of permeability was 3.033 × 10^-13. CONCLUSIONS: Results of the study revealed a strong dependence of biomechanical effects on the excitation frequency, initial bubble radius, and vessel radius. Numerical simulations could provide insight into understanding the mechanism behind bubble-vessel interactions by UDM, which may explore the potential for further improvements to medical applications.


Assuntos
Microbolhas , Microvasos , Elasticidade , Estresse Mecânico , Ultrassonografia
17.
Front Cell Dev Biol ; 9: 714996, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34568327

RESUMO

This study aimed to determine the role of dexmedetomidine (Dex) in neuropathic pain (NP) after chronic constriction injury (CCI) in a rat model as well as its underlying mechanism. First, a CCI rat model was established. After treatment with Dex, the severity of NP was ascertained by monitoring paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) at different time points. Immunohistochemical analysis was performed to determine the levels of Keap1 and Nrf2 in the spinal cord. Furthermore, the levels of Keap1-Nrf2-HO-1 pathway molecules, apoptotic proteins, and antioxidant genes in the spinal cord or isolated primary microglia were determined using quantitative polymerase chain reaction and western blotting. The release of proinflammatory cytokines was detected via enzyme-linked immunosorbent assay. To evaluate Dex-treated CCI-induced NP via the Keap1-Nrf2-HO-1 pathway, the rats were intrathecally injected with lentivirus to upregulate or downregulate the expression of Keap1. We found that Dex inhibited pathological changes and alleviated sciatic nerve pain as well as repressed inflammation, apoptosis, and redox disorders of the spinal cord in CCI rats. Keap1 protein expression was substantially downregulated, whereas Nrf2 and HO-1 expressions were significantly upregulated in the spinal cord after Dex administration. Additionally, Keap1 overexpression counteracted Dex-mediated inhibition of NP. Keap1 overexpression led to a decrease in Nrf2 and HO-1 levels as well as PWT and PWL but led to an aggravation of inflammation and antioxidant disorders and increased apoptosis. Keap1 silencing alleviated NP in rats with CCI, as evidenced by an increase in PWT and PWL. Keap1 depletion resulted in the alleviation of inflammation and spinal cord tissue injury in CCI rats. Collectively, these findings suggest that Dex inhibits the Keap1-Nrf2-HO-1-related antioxidant response, inflammation, and apoptosis, thereby alleviating NP in CCI rats.

18.
Front Chem ; 9: 717201, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34368087

RESUMO

In recent years, single-atom catalysts (SACs) have received extensive attention due to their unique structure and excellent performance. Currently, a variety of porous materials are used as confined single-atom catalysts, such as zeolites, metal-organic frameworks (MOFs), or carbon nitride (CN). The support plays a key role in determining the coordination structure of the catalytic metal center and its catalytic performance. For example, the strong interaction between the metal and the carrier induces the charge transfer between the metal and the carrier, and ultimately affects the catalytic behavior of the single-atom catalyst. Porous materials have unique chemical and physical properties including high specific surface area, adjustable acidity and shape selectivity (such as zeolites), and are rational support materials for confined single atoms, which arouse research interest in this field. This review surveys the latest research progress of confined single-atom catalysts for porous materials, which mainly include zeolites, CN and MOFs. The preparation methods, characterizations, application fields, and the interaction between metal atoms and porous support materials of porous material confined single-atom catalysts are discussed. And we prospect for the application prospects and challenges of porous material confined single-atom catalysts.

19.
Math Biosci Eng ; 18(2): 1154-1168, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33757180

RESUMO

The aim of this study is to estimate the effects of some acoustic parameters on thermal lesions of atherosclerotic plaques in high-intensity focused ultrasound (HIFU) fields. A fluid-solid thermal coupling model is presented for describing the temperature elevation and thermal ablation of atherosclerotic plaque. A finite element approach is used to solve the coupling equations in cylindrical coordinates. The model considers the effect of the wall thickness of large arteries. The extent of the tissue lesion is determined by the accumulated thermal lesion with Arrhenius integral equation at each location. The results show the lesion size of atherosclerotic plaque is positively correlated to the excited frequency and acoustic output power with heating time. The computational model indicates HIFU may present a novel option for thermal ablation of atherosclerotic plaques with a completely non-invasive treatment paradigm.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Placa Aterosclerótica , Acústica , Humanos , Placa Aterosclerótica/diagnóstico por imagem
20.
Eur J Pharmacol ; 897: 173945, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33596416

RESUMO

The objective of study was to investigate the inhibitory effect of sinomenine on neuropathic pain on dorsal root ganglia (DRG). The DRG cell line and spinal nerve ligation (SNL) model were used in this study. The effect of sinomenine on the cell viability was examined by MTT assay. The expression of p38 MAPK, NF-κB, c-fos, SP and TNF-α was detected by using immunofluorescence and immunohistochemistry assay. We also assessed the level of p-CaMKII, COX-2, p-CREB, IL-17A, TLR4 and IL-1ß via western blotting and RT-qPCR. Compared to the controls, sinomenine showed a protective effect on TNF-α-induced apoptosis on DRG cells in a dose-dependent manner, with an increase of cell viability and a decrease of reactive oxygen species level as well as LDH release. Parallelly, sinomenine treatment significantly reduced the expression of various factors related to stress and inflammation, including p38 MAPK, NF-κB, c-fos, p-CAMKII, COX-2, p-CREB, TLR4 and IL-17A in DRG cells in vitro. Furthermore, we found that administration of sinomenine significantly reduced mechanical withdrawal threshold and thermal withdrawal latency and inhibited the inflammation and activation of p38 signaling in SNL rats. It is noting that combined therapy of sinomenine and pulsed radiofrequency exhibited higher efficacy of dorsal root ganglia inflammation than single treatment as well as the combination of oxycodone and pulsed radiofrequency. Sinomenine inhibited the apoptosis of DRG cell by regulating p38 MAPK/CREB signalling pathway, which provides evidence to alleviate neuropathic pain in clinic.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Gânglios Espinais/efeitos dos fármacos , Inflamação/prevenção & controle , Morfinanos/farmacologia , Neuralgia/prevenção & controle , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Analgésicos Opioides/farmacologia , Animais , Apoptose/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Linhagem Celular , Terapia Combinada , Modelos Animais de Doenças , Gânglios Espinais/enzimologia , Gânglios Espinais/patologia , Gânglios Espinais/fisiopatologia , Inflamação/enzimologia , Inflamação/patologia , Inflamação/fisiopatologia , Mediadores da Inflamação/metabolismo , Masculino , Neuralgia/enzimologia , Neuralgia/patologia , Neuralgia/fisiopatologia , Oxicodona/farmacologia , Limiar da Dor/efeitos dos fármacos , Tratamento por Radiofrequência Pulsada , Ratos Sprague-Dawley , Transdução de Sinais
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