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1.
Nano Lett ; 24(18): 5453-5459, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38682680

RESUMO

Voltage-controlled oscillators, serving as fundamental components in semiconductor chips, find extensive applications in diverse modules such as phase-locked loops, clock generators, and frequency synthesizers within high-frequency integrated circuits. This study marks the first implementation of superconducting Josephson probe microscopy for near-field microwave detection on multiple voltage-controlled oscillators. Focusing on spectrum tracking, various phenomena, such as stray spectra and frequency drifts, were found under nonsteady operating states. Parasitic electromagnetic fields, originating from power supply lines and frequency divider circuits, were identified as sources of interference between units. The investigation further determined optimal working states by analyzing features of the microwave distributions. Our research not only provides insights into the optimization of circuit design and performance enhancement in oscillators but also emphasizes the significance of nondestructive near-field microwave microscopy as a pivotal tool in characterizing integrated millimeter-wave chips.

2.
Anal Chem ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39018067

RESUMO

Efficient carrier separation is vitally crucial to improving the detection sensitivity of photoelectrochemical (PEC) biosensors. Here, we developed a facile strategy to efficiently regulate the carrier separation efficiency of the photoactive matrix BiOI and In2S3 signal label functionalized paper chip by manipulation of electrons spin-state and rational design of electron transport pathways. The spin-dependent electronic structures of BiOI and In2S3 were regulated via enhanced electron-spin parallel alignment induced by an external magnetic field, markedly retarding carrier recombination and extending their lifetime. Simultaneously, with the progress of the target-induced catalytic hairpin assembly process, the transfer path of photogenerated carriers was changed, leading to a switch in photocurrent polarity from cathode to anode. This reversed electron transport pathway not only boosted the separation ability of photogenerated electrons but also eliminated false-positive and false-negative signals, thereby further improving the detection sensitivity. As a proof of concept, the well-designed magnetic field-stimulated paper-based PEC biosensor showed highly selectivity and sensitivity for acetamiprid assay with a wide linear range of 1 fM to 20 nM and an ultralow detection limit of 0.73 fM. This work develops a universal strategy for improving the sensitivity of biosensors and exhibits enormous potential in the fields of bioanalysis and clinical diagnosis.

3.
Molecules ; 29(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38893285

RESUMO

In the study, natural deep eutectic solvents (NADESs) were used as alternatives to traditional chemical solvents for the extraction of polyphenols from Elaeagnus angustifolia L. Nine NADESs were tested for the first time and compared with ethanol and water (traditional solvents) regarding the extraction of phenolic compounds from E. angustifolia L. These solvents were particularly effective at extracting polyphenols, whose low water solubility usually requires high amounts of organic solvents. The solvent based on choline chloride and malonic acid provided optimal results and was selected for further optimization. The effects of material-to-liquid ratio, ultrasound time, and ultrasound temperature on the extraction efficiency were studied through single-factor experiments. These parameters were optimized by Box-Behnken design using response surface methodology. The optimal conditions identified were 49.86 g/mL of material-to-liquid ratio, 31.10 min of ultrasound time, and 62.35 °C of ultrasound temperature, resulting in a high yield of 140.30 ± 0.19 mg/g. The results indicated that the NADES extraction technique provided a higher yield than the conventional extraction process. The antioxidant activity of the extract of polyphenols from E. angustifolia L. was determined, and UPLC-IMS-QTOF-MS was used to analyze the phenolic compounds in it. The results revealed that the scavenging ability of 1,1-diphenyl-2-picryl-hydrazil and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) extracted by NADES was higher than that of polyphenols extracted by water and ethanol. Furthermore, a total of 24 phenolic compounds were identified in the extract. To the best of our knowledge, this is the first study in which a green and efficient NADES extraction method has been used to extract bioactive polyphenols from E. angustifolia L., which could provide potential value in pharmaceuticals, cosmetics, and food additives.


Assuntos
Antioxidantes , Elaeagnaceae , Extratos Vegetais , Polifenóis , Polifenóis/química , Polifenóis/isolamento & purificação , Extratos Vegetais/química , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Elaeagnaceae/química , Solventes Eutéticos Profundos/química , Química Verde , Solventes/química
4.
Angew Chem Int Ed Engl ; 63(18): e202401924, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38366134

RESUMO

Nitrate electroreduction reaction (eNO3 -RR) to ammonia (NH3) provides a promising strategy for nitrogen utilization, while achieving high selectivity and durability at an industrial scale has remained challenging. Herein, we demonstrated that the performance of eNO3 -RR could be significantly boosted by introducing two-dimensional Cu plates as electrocatalysts and eliminating the general carrier gas to construct a steady fluid field. The developed eNO3 -RR setup provided superior NH3 Faradaic efficiency (FE) of 99 %, exceptional long-term electrolysis for 120 h at 200 mA cm-2, and a record-high yield rate of 3.14 mmol cm-2 h-1. Furthermore, the proposed strategy was successfully extended to the Zn-nitrate battery system, providing a power density of 12.09 mW cm-2 and NH3 FE of 85.4 %, outperforming the state-of-the-art eNO3 -RR catalysts. Coupled with the COMSOL multiphysics simulations and in situ infrared spectroscopy, the main contributor for the high-efficiency NH3 production could be the steady fluid field to timely rejuvenate the electrocatalyst surface during the electrocatalysis.

5.
BMC Gastroenterol ; 23(1): 161, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208605

RESUMO

INTRODUCTION: Chronic erosive gastritis (CEG) is closely related to gastric cancer, which requires early diagnosis and intervention. The invasiveness and discomfort of electronic gastroscope have limited its application in the large-scale screening of CEG. Therefore, a simple and noninvasive screening method is needed in the clinic. OBJECTIVES: The aim of this study is to screen potential biomarkers that can identify diseases from the saliva samples of CEG patients using metabolomics. METHODS: Saliva samples from 64 CEG patients and 30 healthy volunteers were collected, and metabolomic analysis was performed using UHPLC-Q-TOF/MS in the positive and negative ion modes. Statistical analysis was performed using both univariate (Student's t-test) and multivariate (orthogonal partial least squares discriminant analysis) tests. Receiver operating characteristic (ROC) analysis was conducted to determine significant predictors in the saliva of CEG patients. RESULTS: By comparing the saliva samples from CEG patients and healthy volunteers, 45 differentially expressed metabolites were identified, of which 37 were up-regulated and 8 were down-regulated. These differential metabolites were related to amino acid, lipid, phenylalanine metabolism, protein digestion and absorption, and mTOR signaling pathway. In the ROC analysis, the AUC values of 7 metabolites were greater than 0.8, among which the AUC values of 1,2-dioleoyl-sn-glycoro-3-phosphodylcholine and 1-stearoyl-2-oleoyl-sn-glycoro-3-phospholine (SOPC) were greater than 0.9. CONCLUSIONS: In summary, a total of 45 metabolites were identified in the saliva of CEG patients. Among them, 1,2-dioleoyl-sn-glycoro-3-phosphorylcholine and 1-stearoyl-2-oleoyl-sn-glycoro-3-phosphorine (SOPC) might have potential clinical application value.


Assuntos
Gastrite , Metaboloma , Humanos , Metabolômica/métodos , Biomarcadores/metabolismo , Aminoácidos , Gastrite/diagnóstico
6.
Angew Chem Int Ed Engl ; 61(39): e202207252, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-35819244

RESUMO

Rather than just focusing on the catalyst itself in the electrocatalytic CO2 reduction reaction (eCO2 RR), as previously reviewed elsewhere, we herein extend the discussion to the special topic of the microenvironment around the electrocatalytic center and present a comprehensive overview of recent research progress. We categorize the microenvironment based on the components relevant to electrocatalytic active sites, i.e., the catalyst surface, substrate, co-reactants, electrolyte, membrane, and reactor. Supported by most of the reported articles, the relevant factors affecting the catalytic performance of eCO2 RR are then discussed in detail, and existing challenges and potential solutions are mentioned. Perspectives for the future research on eCO2 RR, including the integration of different microenvironment factors, the extension to industrial application by coupling with carbon capture and conversion, and separation of products, are also discussed.

7.
J Anesth ; 34(3): 434-444, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32133540

RESUMO

Neuraxial anesthesia is a common practice in obstetrics. Evidence suggests that preprocedural ultrasound versus the conventional landmark location method accurately identifies a given intervertebral space and predicts the needle insertion depth required to reach the spinal canal. However, whether the preprocedural ultrasound examination improves the first-pass success (FPS) rate remains elusive. Major databases were systematically searched for all relevant studies published in English up to June 2019. Eighteen randomized controlled trials including 1844 patients were enrolled. The quality of eligible studies was assessed, and predefined outcomes were synthesized by meta-analysis. The primary results showed that preprocedural ultrasound increased the FPS rate in patients with predicted puncture difficulty but not in patients who were easily punctured. Preprocedural ultrasound reduced the number of redirections and punctures and decreased the incidence of vascular puncture and backache. There was no evidence of a reduction in failed punctures. We also noted that preprocedural ultrasound prolonged the identification time but not the procedure time. Thus, this systematic review provides evidence that preprocedural ultrasound does not improve the FPS rate of neuraxial anesthesia in patients who are easily palpated, although it increases the FPS rate in patients who are difficult to palpate.


Assuntos
Raquianestesia , Obstetrícia , Feminino , Humanos , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Ultrassonografia , Ultrassonografia de Intervenção
8.
Mol Pain ; 14: 1744806918762205, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29448914

RESUMO

Therapies treating psoriasis can be categorized into five classes according to their mechanism: anti-metabolites (AM), anti-interleukin-12/23 agents (anti-IL12/23), anti-interleukin-17 agents (anti-IL17), anti-T-cell agent (ANT), and anti-tumor necrosis factor-α agent (anti-TNF-α). This network meta-analysis (NMA) aimed to give a quantitative and systemic evaluation of safety and efficacy for the five kinds of therapies mentioned above. Odds ratios and mean differences were calculated to evaluate binary and continuous outcomes, respectively. Forest plots were conducted to show the performance of pair-wise comparison of above therapies in each outcome, and surface under the cumulative ranking curves was given to evaluate the relative ranking of above therapies in each outcome. Node splitting was conducted to evaluate the consistency between direct and indirect evidence. Direct comparisons from 65 studies (32,352 patients) were included in this NMA. Our results showed an excellent efficacy of anti-IL12/23 and anti-IL17. However, these two therapies and anti-TNF-α were revealed to have a high possibility to cause adverse effects (AEs) such as infections. Additionally, node splitting showed that no inconsistency appeared between the direct and indirect comparisons. Anti-IL12/23 was the most recommended therapy according to this NMA. Anti-IL17 had similar efficacy to anti-IL12/23 but should be applied with caution since it has poor performance in safety outcomes.


Assuntos
Metanálise em Rede , Psoríase/terapia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Índice de Gravidade de Doença , Resultado do Tratamento
9.
BMC Infect Dis ; 18(1): 75, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29433428

RESUMO

BACKGROUND: Persons with chronic hepatitis B (CHB) infection were reported to suffer severe disease after hepatitis E virus (HEV) superinfection, but the studies regarding HEV seroprevalence in this population were limited. A recent study in Vietnam found higher HEV seroprevalence among CHB patients compared with healthy controls. METHODS: A community-based case-control study was conducted in two counties of Shandong province, China, where hepatitis E incidence was at the highest (Rushan) and lowest (Zhangqiu) in the province based on data from routine public health surveillance. Four townships were selected randomly from each county and all residents in these townships were tested for hepatitis B surface antigen (HBsAg). Those tested positive for HBsAg (CHB group) and the 1:1 age and sex-matched HBsAg-negative residents (control group) were included. Anti-HEV IgM and IgG were tested and positive rates of IgG and IgM were compared between the CHB group and the control group. RESULTS: In total, 2048 CHB participants and 2054 controls were included in the study. In the CHB group, HEV IgG seroprevalence was 9.16% (95% CI: 7.47-11.09) in Zhangqiue and 38.06% (95% CI: 35.07-41.19) in Rushan (P < 0.001); the corresponding rates of IgM were 0.1% (95% CI: 0.002-0.54) and 1.57% (95% CI: 0.90-2.53), respectively (P < 0.001). HEV IgG seroprevalence was similar between CHB group and the control group in both counties (P = 0.21, P = 0.47, respectively) and the same results were found for the positive rate of IgM (P = 0.103, P = 0.262, respectively). Multivariable analysis showed the status of HBsAg was not independently associated with the status of anti-HEV IgG in either Zhangqiu or Rushan [P = 0.187, OR = 1.23(95% CI: 0.90, 1.68); P = 0.609, OR = 1.05 (95% CI: 0.87, 1.26)]. CONCLUSIONS: The seroprevalence of HEV varies greatly in different geographic areas, but the seroprevalence is similar between populations with and without CHB. CHB patients residing in high HEV endemic areas might be at higher risk for HBV-HEV superinfection.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/complicações , Hepatite E/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , China/epidemiologia , Feminino , Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite B/metabolismo , Hepatite B Crônica/virologia , Hepatite E/complicações , Vírus da Hepatite E/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Estudos Soroepidemiológicos , Adulto Jovem
10.
Small ; 13(24)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28481435

RESUMO

A noble-metal-free electrocatalyst is fabricated via in situ formation of nanocomposite of nitrogen-doped graphene quantum dots (NGQDs) and Ni3 S2 nanosheets on the Ni foam (Ni3 S2 -NGQDs/NF). The resultant Ni3 S2 -NGQDs/NF can serve as an active, binder-free, and self-supported catalytic electrode for direct water splitting, which delivers a current density of 10 mA cm-2 at an overpotential of 216 mV for oxygen evolution reaction and 218 mV for hydrogen evolution reaction in alkaline media. This bifunctional electrocatalyst enables the construction of an alkali electrolyzer with a low cell voltage of 1.58 V versus reversible hydrogen electrode (RHE) at 10 mA cm-2 . The experimental results and theoretical calculations demonstrate that the synergistic effects of the constructed active interfaces are the key factor for excellent performance. The nanocomposite of NGQDs and Ni3 S2 nanosheets can be promising water splitting electrocatalyst for large-scale hydrogen generation or other energy storage and conversion applications.

11.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 37(4): 410-413, 2017 04.
Artigo em Zh | MEDLINE | ID: mdl-30650495

RESUMO

Objective To observe the correlation of hepatocyte growth factor (HGF) and Hepato- cyte growth factor receptor (c-Met ) in serum and gastric mucosa tissues of chronic erosive gastritis pa- tients. Methods Totally 70 patients with chronic erosive gastritis were selected and assigned to turbidity toxin intrinsic syndrome group and Gan-wei disharmony syndrome group, HGF expression level of ser- um,and HGF,c-Met expression level of gastric mucosa tissues were measured;the correlation of HGF and c-Met in gastric mucosa tissues, and the correlation of HGF in serum and gastric mucosa tissues were analyzed. Results The expression level of HGF and c-Met in turbidity toxin intrinsic syndrome group was higher than that in Gan-wei disharmony syndrome group (P <0. 05) ; the expression level of HGF in gastric mucosa tissues was positively correlated with c-Met(r =0. 831 , P <0. 05) ; the expression level of HGF in serum was positively correlated with that of gastric mucosa tissues(r =0. 656, P <0. 05). Conclusions There was correlation between turbidity toxin intrinsic syndrome of Chronic Erosive Gastri- tis patients and the expression level of HGF and c-Met.


Assuntos
Gastrite , Fator de Crescimento de Hepatócito , Proteínas Proto-Oncogênicas c-met , Mucosa Gástrica , Gastrite/sangue , Gastrite/metabolismo , Fator de Crescimento de Hepatócito/sangue , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Medicina Tradicional Chinesa , Proteínas Proto-Oncogênicas c-met/sangue , Proteínas Proto-Oncogênicas c-met/metabolismo , Úlcera Gástrica
12.
Cancer Invest ; 33(9): 420-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26180943

RESUMO

Liquid chromatograph-mass spectrometer (LC/MS) based labeled with isobaric mass tags for relative and absolute quantitation (iTRAQ) analyses were performed to identify differentially expressed proteins from normal and cancerous human colorectal tissues. Around 802 proteins were identified, 68 proteins of which were defined as differentially expressed proteins. Bioinformatics analysis indicated that these differentially expressed proteins correlated with several specific cellular processes and pathways which have relationships with pathological changes of colorectal cancer (CRC). EHD2 were selected to verify its expression patterns and localization using western blotting and immunohistochemistry respectively. LC/MS-based iTRAQ proteomic approach would provide new information about the character of CRC.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Expressão Gênica/genética , Proteínas de Neoplasias/genética , Proteínas de Transporte/genética , Cromatografia Líquida/métodos , Humanos , Espectrometria de Massas/métodos
13.
Am J Emerg Med ; 32(11): 1391-4, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25224024

RESUMO

BACKGROUND: Conventional needle cricothyroidotomy uses blind manipulation. We investigated the feasibility and efficiency of a new visually guided needle cricothyroidotomy technique. METHODS: A 0.9-mm microimaging fiber was delivered into a 14G needle to develop a visual puncture system. 10 inexperienced physicians were randomly assigned to perform 10 repeated needle cricothyroidotomy in each group with both conventional method and visual puncture in a manikin. Tracheal lumen puncture time and number of procedure-related complications were recorded. RESULTS: Under visual guidance, the needle successfully reached the tracheal lumen. The anatomy of the upper and lower airways was acquired by further advancing the microimaging fiber into the tracheal lumen of the visual group. The tracheal lumen puncture time was significantly less in the visual group than in the conventional group (3.85 ± 1.54 vs. 9.84 ± 1.08 seconds, P < .001). Damage to the posterior tracheal wall was not observed in the visual group; however, 21% of manikins in the conventional group had procedure-related complications. CONCLUSIONS: Our results demonstrate that visual needle cricothyroidotomy is feasible, and may lead to a decrease in procedure time and procedure-related complications compared to the conventional procedure. In addition, this strategy may also provide useful information for diagnostic purposes; therefore, visual needle cricothyroidotomy may be a new strategy for the management of difficult airways in future care.


Assuntos
Manuseio das Vias Aéreas/métodos , Cartilagem Cricoide/cirurgia , Manequins , Agulhas , Cirurgia Vídeoassistida/métodos , Competência Clínica , Estudos de Viabilidade , Humanos , Punções
14.
J Mater Sci Mater Med ; 25(2): 273-82, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24150983

RESUMO

This study focused on the synthesis, characterization and cytocompatibility of a biodegradable polymer by the cross-linking from poly(ethylene glycol-co-lactide) dimethacrylate (PLEGDMA), polyethylene glycol diacrylate (PEGDA) and N-isopropylacrylamide, where PLEGDMA was synthesized by ring-opening oligomerization of poly(ethylene glycol) with different molecular weights (Mn = 400, 600, 1000, 2000 Da) and L-lactide using low toxic iron(III) acetylacetonate (Fe(acac)3) as the catalyst and subsequently being terminated with dimethacrylate. The product, PLEGDMA, was analyzed to confirm its chemistry using FTIR spectroscopy, (1)H NMR spectra and gel permeation chromatography etc. The thermodynamic properties, mechanical behaviors, surface hydrophilicity, degradability and cytotoxicity of the cross-linked product were evaluated by differential scanning calorimetry, tensile tests, contact angle measurements and cell cultures. The effects of reaction variables such as PEGDA content and reactants ratio were optimized to achieve a material with low glass transition temperature (Tg), high wettability and preferable mechanical characteristics. Using a tubular mould which has been patented in our group, a tubular scaffold with predetermined dimension and pattern was fabricated, which aims at guiding the growth and phenotype regulation of esophageal primary cells like fibroblast and smooth muscle cell towards fabricating tissue engineered esophagus in future.


Assuntos
Materiais Biocompatíveis , Esôfago , Compostos Férricos/química , Polímeros/química , Engenharia Tecidual , Células Cultivadas , Humanos , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Cancer Med ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38168130

RESUMO

OBJECTIVE: This study investigates the relationship between financial toxicity and medical cost-coping behaviors (MCCB) in Chinese patients with lung cancer, with a particular focus on the moderating role of health insurance. METHODS: We surveyed 218 patients with lung cancer and assessed their Comprehensive Score for Financial Toxicity (COST) and self-reported MCCB. Patients were categorized into Urban Employee's Basic Medical Insurance (UEBMI) group and Urban-Rural Resident Basic Medical Insurance Scheme (URRBMI) groups by their medical insurance, and matched for socioeconomic, demographic, and disease characteristics via propensity score. RESULTS: Significant different characteristics were noted between UEBMI patients and URRBMI patients. Patients with UEBMI had higher COST scores but lower levels of MCCB compared to URRBMI patients in the original dataset. After data matching, multivariate logit regression analysis showed that better financial toxicity was associated with lower levels of MCCB (OR = 0.95, 95% CI: 0.92-0.99). Health insurance type did not have a direct association with cost-coping behaviors, but an interaction was observed between health insurance type and financial toxicity. Among patients with URRBMI, better financial toxicity was associated with lower levels of cost-coping behaviors (OR = 0.89, 95% CI: 0.83-0.95). Patients with UEBMI had a lower probability of engaging in any cost-coping behaviors in situations of worse financial toxicity compared to patients with URRBMI. CONCLUSION: The findings suggest that financial toxicity is correlated with MCCB in Chinese patients with lung cancer. The type of health insurance, specifically UEBMI and URRBMI, plays a moderating role in this relationship. Understanding these dynamics is essential for developing targeted interventions and policies to mitigate financial toxicity and improve patients' management of medical costs.

16.
Adv Mater ; 36(28): e2312566, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38630368

RESUMO

Transition metal oxides (TMOs) are widely studied for loading of various catalysts due to their low cost and high structure flexibility. However, the prevailing close-packed nature of most TMOs crystals has restricted the available loading sites to surface only, while their internal bulk lattice remains unactuated due to the inaccessible narrow space that blocks out most key reactants and/or particulate catalysts. Herein, using tunnel-structured MnO2, this study demonstrates how TMO's internal lattice space can be activated as extra loading sites for atomic Ag in addition to the conventional surface-only loading, via which a dual-form Ag catalyst within MnO2 skeleton is established. In this design, not only faceted Ag nanoparticles are confined onto MnO2 surface by coherent lattice-sharing, Ag atomic strings are also seeded deep into the sub-nanoscale MnO2 tunnel lattice, enriching the catalytically active sites. Tested for electrochemical CO2 reduction reaction (eCO2RR), such dual-form catalyst exhibits a high Faradaic efficiency (94%), yield (67.3 mol g-1 h-1) and durability (≈48 h) for CO production, exceeding commercial Ag nanoparticles and most Ag-based electrocatalysts. Theoretical calculations further reveal the concurrent effect of such dual-form catalyst featuring facet-dependent eCO2RR for Ag nanoparticles and lattice-confined eCO2RR for Ag atomic strings, inspiring the future design of catalyst-substrate configuration.

17.
iScience ; 26(4): 106407, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37020967

RESUMO

An electrochemical approach for ammonia production is successfully developed by coupling the anodic dinitrogen oxidation reaction (NOR) and cathodic hydrogen evolution reaction (HER) within a well-designed membraneless flow electrolyzer. The obtained reactor shows the preferential yield of ammonia over nitrogen oxides on the vanadium nitride catalyst surface. At an applied oxidation potential of 2.25 V versus the reversible hydrogen electrode (vs RHE), a promoted ammonia production rate and Faradaic efficiency (FE) were obtained with 9.9 mmol g-1 h-1 (0.029 mmol cm-2 h-1) and 4.8%, respectively. Besides, the negative affection of ammonia contamination is efficiently alleviated. Density functional theory calculations revealed that the thermodynamic energy needed to produce ammonia (-0.63 eV) is far lower than that of producing nitrogen oxide (0.96 eV) from hydrogenated nitrogen oxides [∗N2OH] splitting, confirming the coupling of NOR and HER.

18.
PLoS One ; 18(3): e0282928, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36913401

RESUMO

BACKGROUND: Infectious diseases are a major threat to public health, causing serious medical consumption and casualties. Accurate prediction of infectious diseases incidence is of great significance for public health organizations to prevent the spread of diseases. However, only using historical incidence data for prediction can not get good results. This study analyzes the influence of meteorological factors on the incidence of hepatitis E, which are used to improve the accuracy of incidence prediction. METHODS: We extracted the monthly meteorological data, incidence and cases number of hepatitis E from January 2005 to December 2017 in Shandong province, China. We employ GRA method to analyze the correlation between the incidence and meteorological factors. With these meteorological factors, we achieve a variety of methods for incidence of hepatitis E by LSTM and attention-based LSTM. We selected data from July 2015 to December 2017 to validate the models, and the rest was taken as training set. Three metrics were applied to compare the performance of models, including root mean square error(RMSE), mean absolute percentage error(MAPE) and mean absolute error(MAE). RESULTS: Duration of sunshine and rainfall-related factors(total rainfall, maximum daily rainfall) are more relevant to the incidence of hepatitis E than other factors. Without meteorological factors, we obtained 20.74%, 19.50% for incidence in term of MAPE, by LSTM and A-LSTM, respectively. With meteorological factors, we obtained 14.74%, 12.91%, 13.21%, 16.83% for incidence, in term of MAPE, by LSTM-All, MA-LSTM-All, TA-LSTM-All, BiA-LSTM-All, respectively. The prediction accuracy increased by 7.83%. Without meteorological factors, we achieved 20.41%, 19.39% for cases in term of MAPE, by LSTM and A-LSTM, respectively. With meteorological factors, we achieved 14.20%, 12.49%, 12.72%, 15.73% for cases, in term of MAPE, by LSTM-All, MA-LSTM-All, TA-LSTM-All, BiA-LSTM-All, respectively. The prediction accuracy increased by 7.92%. More detailed results are shown in results section of this paper. CONCLUSIONS: The experiments show that attention-based LSTM is superior to other comparative models. Multivariate attention and temporal attention can greatly improve the prediction performance of the models. Among them, when all meteorological factors are used, multivariate attention performance is better. This study can provide reference for the prediction of other infectious diseases.


Assuntos
Aprendizado Profundo , Hepatite E , Humanos , Incidência , China/epidemiologia , Conceitos Meteorológicos
19.
Biotechnol Genet Eng Rev ; : 1-22, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37066895

RESUMO

Leonurus japonicus Houtt is an important anti-skin pigmentation herb used in traditional Chinese medicine. However, the molecular basis for this activity is complex and not fully understood. In this study, water and ethanol extracts and polysaccharide extract from L. japonicus (LJPs) were analyzed by LC-MS/MS and HPLC-DAD separately. Cytotoxicity was analyzed by using CCK-8, antioxidant activity using flow cytometer, anti-MMPs, anti-tyrosinase and signalling pathway analysis using Western blotting to investigate their anti-melanogenesis function. The results showed that the water and ethanol extracts contained alkaloids, flavonoids, and phenolic acids. The LJPs mainly contain glucose, fucose, glucuronic acid, mannose, threonine and arginine, and structure characterization by FITR analyses indicated that LJPs have ß- or α-D-glycosidic bonds and contain pyranose rings. The L. japonicus extracts displayed high cell viability at their maximum concentration. The water extract and polysaccharides significantly reduced lipopolysaccharide (LPS)-induced intracellular reactive oxygen species (ROS) content and exhibited a cytoprotective role. Also, these extracts displayed higher matrix metalloproteinase-2 (anti-MMP-2), anti-MMP-9 and anti-tyrosinase activities. Furthermore, the polysaccharides displayed significantly greater inhibitory effect on intracellular ROS and tyrosinase protein expression than α-arbutin and ursolic acid used for the clinical treatment of skin pigmentation. This study also investigated the polysaccharide inhibition of melanin synthesis by repressing the expression of melanocytic lineage-specific transcription factor (MITF) and melanogenic enzymes via modulation of the phosphoinositide 3-kinase (PI3K-Akt-mTOR) and ß-catenin pathways. The overall results indicate that L. japonicus is a promising candidate for anti-pigmentation treatment.

20.
Small Methods ; : e2301307, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38088567

RESUMO

Despite that extensive efforts have been dedicated to the search for advanced catalysts to boost the electrocatalytic nitrobenzene reduction reaction (eNBRR), its progress is severely hampered by the limited understanding of the relationship between catalyst structure and its catalytic performance. Herein, this review aims to bridge such a gap by first analyzing the eNBRR pathway to present the main influential factors, such as electrolyte feature, applied potential, and catalyst structure. Then, the recent advancements in catalyst design for eNBRR are comprehensively summarized, particularly about the impacts of chemical composition, morphology, and crystal facets on regulating the local microenvironment, electron and mass transport for boosting catalytic performance. Finally, the future research of eNBRR is also proposed from the perspectives of performance enhancement, expansion of product scope, in-depth understanding of the reaction mechanism, and acceleration of the industrialization process through the integration of upstream and downstream technologies.

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