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1.
Artigo em Inglês | MEDLINE | ID: mdl-38603469

RESUMO

The electrochemical interface formed between an electrode and an electrolyte significantly affects the rate and mechanism of the electrode reaction through its structure and properties, which vary across the interface. The scope of the interface has been expanded, along with the development of energy electrochemistry, where a solid-electrolyte interphase may form on the electrode and the active materials change properties near the surface region. Developing a comprehensive understanding of electrochemical interfaces and interphases necessitates three-dimensional spatial resolution characterization. Atomic force microscopy (AFM) offers advantages of imaging and long-range force measurements. Here we assess the capabilities of AFM by comparing the force curves of different regimes and various imaging modes for in situ characterizing of electrochemical interfaces and interphases. Selected examples of progress on work related to the structures and processes of electrode surfaces, electrical double layers, and lithium battery systems are subsequently illustrated. Finally, this review provides perspectives on the future development of electrochemical AFM.

2.
J Affect Disord ; 354: 126-135, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38479517

RESUMO

BACKGROUND: Emotion regulation deficits, particularly in cognitive reappraisal, are crucial in depression and anxiety. However, research on the neural mechanisms of implicit emotion regulation is lacking, and it remains unclear whether these mechanisms are shared or distinct between the two disorders. METHODS: We investigated the neural mechanisms of implicit cognitive reappraisal in 28 individuals with major depressive disorder (MDD), 25 with generalized anxiety disorder (GAD), and 30 healthy controls (HC) using functional near-infrared spectroscopy (fNIRS). Participants completed an implicit cognitive reappraisal task and underwent neuropsychological and clinical assessments. RESULTS: We found that MDD patients reported higher levels of rumination and lower utilization of cognitive reappraisal, while GAD patients reported reduced use of perspective-taking. Notably, both MDD and GAD patients exhibited decreased activation in the dorsolateral prefrontal cortex (DLPFC) and orbitofrontal cortex (OFC) compared to HC participants during implicit cognitive reappraisal. Specifically, inadequate OFC activation was observed in MDD patients, while GAD patients demonstrated OFC deactivation during the task. Furthermore, DLPFC activation showed a negative correlation with depression severity in MDD patients, while OFC activation was positively correlated with perspective-taking in GAD patients. LIMITATIONS: fNIRS has limited depth and spatial resolution. CONCLUSION: Our fNIRS study is the first to reveal shared and distinct neurobiological profiles of depression and anxiety in implicit emotion regulation. These findings underscore the significance of reduced DLPFC/OFC activation in emotion regulation impairment and highlight unique OFC activation patterns in these disorders. These insights have potential implications for developing cognitive-behavioral therapy and transcranial magnetic stimulation as treatment approaches.


Assuntos
Transtorno Depressivo Maior , Regulação Emocional , Humanos , Emoções/fisiologia , Transtorno Depressivo Maior/psicologia , Depressão , Imageamento por Ressonância Magnética , Transtornos de Ansiedade/psicologia , Ansiedade , Córtex Pré-Frontal/diagnóstico por imagem
3.
World J Psychiatry ; 14(2): 234-244, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38464769

RESUMO

BACKGROUND: Panic disorder (PD) involves emotion dysregulation, but its underlying mechanisms remain poorly understood. Previous research suggests that implicit emotion regulation may play a central role in PD-related emotion dysregulation and symptom maintenance. However, there is a lack of studies exploring the neural mechanisms of implicit emotion regulation in PD using neurophysiological indicators. AIM: To study the neural mechanisms of implicit emotion regulation in PD with event-related potentials (ERP). METHODS: A total of 25 PD patients and 20 healthy controls (HC) underwent clinical eva-luations. The study utilized a case-control design with random sampling, selecting participants for the case group from March to December 2018. Participants performed an affect labeling task, using affect labeling as the experimental condition and gender labeling as the control condition. ERP and behavioral data were recorded to compare the late positive potential (LPP) within and between the groups. RESULTS: Both PD and HC groups showed longer reaction times and decreased accuracy under the affect labeling. In the HC group, late LPP amplitudes exhibited a dynamic pattern of initial increase followed by decrease. Importantly, a significant group × condition interaction effect was observed. Simple effect analysis revealed a reduction in the differences of late LPP amplitudes between the affect labeling and gender labeling conditions in the PD group compared to the HC group. Furthermore, among PD patients under the affect labeling, the late LPP was negatively correlated with disease severity, symptom frequency, and intensity. CONCLUSION: PD patients demonstrate abnormalities in implicit emotion regulation, hampering their ability to mobilize cognitive resources for downregulating negative emotions. The late LPP amplitude in response to affect labeling may serve as a potentially valuable clinical indicator of PD severity.

4.
Luminescence ; 39(1): e4659, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38286609

RESUMO

Specific biomarker-activatable probes have revolutionized theranostics, being beneficial for precision medicine. Hypoxia is a critical pathological characteristic prevalent in numerous major diseases such as cancers, cardiovascular disorders, inflammatory diseases, and acute ischemia. Aggregation-induced emission luminogens (AIEgens) have emerged as a promising tool to tackle the biomedical issues. Of particular significance are the hypoxia-responsive AIEgens, representing a kind of crucial probe capable of delicately sensing and responding to the hypoxic microenvironment, thereby enhancing the precision of disease diagnosis and treatment. In this review, we summarize the recent advances of hypoxia-responsive AIEgens for varied biomedical applications. The hypoxia-responsive structures based on AIEgens, such as azobenzene, nitrobenzene, and N-oxide are presented, which are in response to the reduction property to bring about significant alternations in response spectra and/or fluorescence intensity. The bioapplications including imaging and therapy of tumor and ischemia diseases are discussed. Moreover, the review sheds light on the future challenges and prospects in this field. This review aims to provide comprehensive guidance and understanding into the development of activatable bioprobes, especially the hypoxia-responsive AIEgens for improving the diagnosis and therapy outcome of related diseases.


Assuntos
Neoplasias , Medicina de Precisão , Humanos , Nanomedicina Teranóstica/métodos , Imagem Óptica/métodos , Isquemia , Corantes Fluorescentes/química , Microambiente Tumoral
5.
Small ; : e2311393, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287737

RESUMO

Electrolyte plays a crucial role in ensuring stable operation of lithium metal batteries (LMBs). Localized high-concentration electrolytes (LHCEs) have the potential to form a robust solid-electrolyte interphase (SEI) and mitigate Li dendrite growth, making them a highly promising electrolyte option. However, the principles governing the selection of diluents, a crucial component in LHCE, have not been clearly determined, hampering the advancement of such a type of electrolyte systems. Herein, the diluents from the perspective of molecular polarity are rationally designed and developed. A moderately fluorinated solvent, 1-(1,1,2,2-tetrafluoroethoxy)propane (TNE), is employed as a diluent to create a novel LHCE. The unique molecular structure of TNE enhances the intrinsic dipole moment, thereby altering solvent interactions and the coordination environment of Li-ions in LHCE. The achieved solvation structure not only enhances the bulk properties of LHCE, but also facilitates the formation of more stable anion-derived SEIs featured with a higher proportion of inorganic species. Consequently, the corresponding full cells of both Li||LiFePO4 and Li||LiNi0.8 Co0.1 Mn0.1 O2 cells utilizing Li thin-film anodes exhibit extended long-term stability with significantly improved average Coulombic efficiency. This work offers new insights into the functions of diluents in LHCEs and provides direction for further optimizing the LHCEs for LMBs.

6.
Plant Dis ; : PDIS02230321RE, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38012822

RESUMO

Gray mold caused by Botrytis cinerea severely threatens the yield of ginseng (Panax ginseng). Various categories of fungicides have been utilized to control gray mold on this crop. In this study, the resistance of 102 isolates of B. cinerea from 11 commercial ginseng-growing regions in China to fungicides was examined. A total of 32.4% were resistant to boscalid, with EC50 values that ranged from 12.26 to 235.87 µg/ml, and 94.1% were resistant to pyraclostrobin, with EC50 values that ranged from 5.88 to 487.72 µg/ml. Except for sdhA and sdhD, the amino acid substitutions of P225F, P225L, N230I, H272Y, and H272R in the sdhB subunit from 24 (4 sensitive [S] and 20 resistant [R]), 5 (1 S and 4 R), 1 (S), 1 (R), and 8 (4 S and 4 R) strains, respectively, and the concurrent amino acid substitutions of G85A + I93V + M158V + V168I in the sdhC subunit from 5 (4 S and 1 R) strains were identified. A G143A substitution in cytochrome b was identified in 96 isolates that were resistant to pyraclostrobin and three that were sensitive to it. The Bcbi-143/144 intron was identified in the other three isolates sensitive to pyraclostrobin, but it was absent in the isolates that harbored the G143A mutation. The results showed that the populations of B. cinerea on ginseng have developed strong resistance to pyraclostrobin. Therefore, it is not recommended to continue using this fungicide to control gray mold on P. ginseng. Boscalid is still effective against most isolates. However, to prevent fungicide resistance, it is recommended to use a mixture of boscalid with other categories of fungicides.

7.
J Psychiatr Res ; 169: 97-104, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38007890

RESUMO

Cognitive reappraisal is an effective emotion regulation strategy involving prefrontal cortex (PFC) control of the amygdala. Its aberrant functioning is closely associated with panic disorder (PD). However, the resting-state functional connectivity (rsFC) between the PFC, implicated in cognitive reappraisal, and the amygdala in PD has not been studied. Thus, this study aims to investigate the rsFC patterns and their association with cognitive reappraisal and PD. This study involved 51 participants, including 26 untreated patients with PD and 25 healthy controls (HC). We evaluated the habit of cognitive reappraisal assessment and the severity of PD using neuropsychological and clinical measures. Resting-state fMRI was utilized to evaluate the rsFC pattern between the PFC, engaged in cognitive reappraisal, and the amygdala. Mediation analysis was performed to explore the role of this rsFC in the relationship between cognitive reappraisal and PD severity. PD patients showed reduced rsFC between the PFC and the amygdala compared to HC. This weakened rsFC was associated with the severity of PD symptoms. Moreover, cognitive reappraisal was negatively correlated with PD severity, and mediation analysis indicated that the rsFC of the PFC-amygdala played a mediating role in this association. Abnormal PFC-amygdala rsFC may play a pivotal role in PD development and/or manifestation and mediate the association between cognitive reappraisal and PD severity, potentially serving as a clinical indicator for monitoring and intervention.


Assuntos
Regulação Emocional , Transtorno de Pânico , Humanos , Transtorno de Pânico/diagnóstico por imagem , Mapeamento Encefálico , Córtex Pré-Frontal/diagnóstico por imagem , Tonsila do Cerebelo/diagnóstico por imagem , Imageamento por Ressonância Magnética
8.
J Laparoendosc Adv Surg Tech A ; 34(3): 280-283, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37844069

RESUMO

Purposes: Dilatation of cystic duct is very rare and had been classified as Todani type VI choledochal cyst. Choledochal cyst combined with dilatation of cystic duct is difficult to diagnose preoperatively. The purpose of this study is to report the rare variants and discuss the significance and laparoscopic management strategy in children. Methods: The subjects for this study were 10 consecutive patients with type VI choledochal cyst who had laparoscopic procedures at our institute between January 2009 and January 2023. Laparoscopic cholecystectomy, excision of the dilated cystic duct, and choledochal cyst were carried out, and the continuity of the biliary duct was re-established through a Roux-en-Y hepaticojejunostomy. Results: Cystic duct combined with the common bile duct dilatation was revealed in all the patients intraoperatively. Laparoscopic procedures were completed with no conversions. The postoperative recovery was uneventful. The mean follow-up duration was 27 ± 12.7 months (range 5-36 months) with no postoperative complications encountered. Conclusions: The rare entity of type VI choledochal cyst should be recognized as a distinct type of choledochal cyst and need to be given enough attention clinically. The laparoscopic procedure is a feasible option for experienced surgeons.


Assuntos
Colecistectomia Laparoscópica , Cisto do Colédoco , Laparoscopia , Criança , Humanos , Cisto do Colédoco/cirurgia , Anastomose em-Y de Roux/métodos , Fígado/cirurgia , Dilatação Patológica/cirurgia , Laparoscopia/métodos
9.
Adv Mater ; 35(52): e2309797, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37973189

RESUMO

Stubborn biofilm infections pose serious threats to human health due to the persistence, recurrence, and dramatically magnified antibiotic resistance. Photodynamic therapy has emerged as a promising approach to combat biofilm. Nevertheless, how to inhibit the bacterial signal transduction system and the efflux pump to conquer biofilm recurrence and resistance remains a challenging and unaddressed issue. Herein, a boric acid-functionalized lipophilic cationic type I photosensitizer, ACR-DMP, is developed, which efficiently generates •OH to overcome the hypoxic microenvironment and photodynamically eradicates methicillin-resistant Staphylococcus aureus (MRSA) and biofilms. Furthermore, it not only alters membrane potential homeostasis and osmotic pressure balance due to its strong binding ability with plasma membrane but also inhibits quorum sensing and the two-component system, reduces virulence factors, and regulates the activity of the drug efflux pump attributed to the glycan-targeting ability, helping to prevent biofilm recurrence and conquer biofilm resistance. In vivo, ACR-DMP successfully obliterates MRSA biofilms attached to implanted medical catheters, alleviates inflammation, and promotes vascularization, thereby combating infections and accelerating wound healing. This work not only provides an efficient strategy to combat stubborn biofilm infections and bacterial multidrug resistance but also offers systematic guidance for the rational design of next-generation advanced antimicrobial materials.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Percepção de Quorum , Humanos , Fármacos Fotossensibilizantes/farmacologia , Antibacterianos/farmacologia , Biofilmes , Testes de Sensibilidade Microbiana
10.
Phys Rev E ; 108(3-1): 034218, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37849154

RESUMO

Electrical turbulence in the heart is considered the culprit of cardiac disease, including the fatal ventricular fibrillation. Optogenetics is an emerging technology that has the capability to produce action potentials of cardiomyocytes to affect the electric wave propagation in cardiac tissue, thereby possessing the potential to control the turbulence, by shining a rotating spiral pattern onto the tissue. In this paper, we present a method to reorder and synchronize electrical turbulence through optogenetics. A generic two-variable reaction-diffusion model and a simplified three-variable ionic cardiac model are used. We discuss cases involving either global or partial illumination.


Assuntos
Iluminação , Miócitos Cardíacos , Simulação por Computador , Potenciais de Ação/fisiologia , Modelos Cardiovasculares
11.
Nano Lett ; 23(21): 9872-9879, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37856869

RESUMO

Lithium metal deposition is strongly affected by the intrinsic properties of the solid-electrolyte interphase (SEI) and working electrolyte, but a relevant understanding is far from complete. Here, by employing multiple electrochemical techniques and the design of SEI and electrolyte, we elucidate the electrochemistry of Li deposition under mass transport control. It is discovered that SEIs with a lower Li ion transference number and/or conductivity induce a distinctive current transition even under moderate potentiostatic polarization, which is associated with the control regime transition of Li ion transport from the SEI to the electrolyte. Furthermore, our findings help reveal the creation of a space-charge layer at the electrode/SEI interface due to the involvement of the diffusion process of Li ions through the SEI, which promotes the formation of dendrite embryos that develop and eventually trigger SEI breakage and the control regime transition of Li ion transport. Our insight into the very initial dendritic growth mechanism offers a bridge toward design and control for superior SEIs.

12.
JACC Case Rep ; 24: 102027, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37869216

RESUMO

IgG4-related disease (IgG4-RD) is a new clinical entity characterized by lymphoplasmacytic lesions rich in IgG4-positive plasma cells. Myocardial involvement is extremely rare and not a typical cardiovascular manifestation of IgG4-RD. We report a rare case of IgG4-RD-associated myocardial mass causing severe aortic incompetence, successfully treated with surgery and corticosteroids. (Level of Difficulty: Intermediate.).

13.
14.
Anal Chem ; 95(41): 15333-15341, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37793058

RESUMO

Accurate control of charge transfer is crucial to investigate the catalytic reaction mechanism of the biological oxidation process that biomedicine participates in. Herein, we have established an assembly model of metalloporphyrin framework (MPF) nanosheets as the active centers of biological enzymes. The introduction of Vitamin C (VC) into the MPF system can precisely modulate its content of charges. The surface-enhanced Raman scattering activity and peroxidase-like catalytic performance are enhanced simultaneously for the first time by manipulating the optimal molar ratio of an MPF to VC and the reaction sequence with target model molecules. We have confirmed that the formation of the intermediate of Fe(2+)-OOH species is specifically enhanced after VC modulation, which indicates that VC can regulate the oxidative stress of the active center of biological enzymes. This discovery not only accurately resolves the mechanism of VC-selective anticancer therapy but also has important significance for the precise treatment of VC synergistic targeting medicines.


Assuntos
Ácido Ascórbico , Metaloporfirinas , Estresse Oxidativo , Antioxidantes/metabolismo , Vitaminas
15.
Curr Oncol ; 30(9): 8444-8463, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37754530

RESUMO

Despite the development of HER2-targeted drugs, achieving favorable outcomes for patients with HR+/HER2+MBC remains challenging. This study utilized Bayesian Network Meta-analysis to compare the efficacy and safety of anti-HER2 combination regimens. The primary analysis focused on progression-free survival (PFS), while secondary analyses included objective response rate, overall survival (OS) and the incidence rate of grade 3/4 adverse events (AEs). A comprehensive search across seven databases identified 25 randomized controlled trials for inclusion in this meta-analysis. For patients eligible for endocrinotherapy, our findings revealed that dual-target combined endocrine therapy, such as Her2-mAb+Her2-mAb+Endo (HR = 0.38; 95%CrI: 0.16-0.88) and Her2-mAb+Her2-tki+Endo (HR = 0.45; 95%CrI: 0.23-0.89), significantly improved PFS compared to endocrine therapy alone. According to the surface under the cumulative ranking curves (SUCRAs), Her2-mAb+Her2-mAb+Endo and Her2-mAb+Her2-tki+Endo ranked highest in terms of PFS and OS, respectively. For patients unsuitable for endocrine therapy, anti-HER2 dual-target combined chemotherapy, such as Her2-mAb+Her2-mAb+Chem (HR = 0.76; 95%CrI: 0.6-0.96) and Her2-mAb+Her2-tki+Chem (HR = 0.48; 95%CrI: 0.29-0.81), demonstrated significant improvements in PFS compared to Her2-mAb+Chem. The results were the same when compared with Her2-tki+Chem. According to the SUCRAs, Her2-mAb+Her2-tki+Chem and Her2-mAb+Her2-mAb+Chem ranked highest for PFS and OS, respectively. Subgroup analyses consistently supported these overall findings, indicating that dual-target therapy was the optimal approach irrespective of treatment line.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Teorema de Bayes , Metanálise em Rede , Bases de Dados Factuais , Intervalo Livre de Progressão
16.
Dig Dis ; 41(5): 685-694, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37579733

RESUMO

BACKGROUND: Mild cellular atypia of esophageal squamous epithelial dysplasia has a risk of progressing to cancer that poses great confusion for pathological diagnosis. There is no research on the diagnosis and differential diagnosis of esophageal squamous dysplasia by the expression of immunohistochemical (IHC) p53. The study aims to conduct a graded diagnosis of esophageal squamous epithelial hyperplasia by combining p53 expressions and microscopic histomorphological characteristics. METHODS: The study was conducted from January 2021 to January 2022 and included a total of 208 cases including 262 specimens with atypical hyperplasia or dysplasia of squamous epithelia discovered by esophageal mucosal biopsy. HE staining was used to grade the epithelial hyperplasia degree, and all cases underwent p53 IHC evaluation. RESULTS: Benign lesions: we did not find any p53 IHC mutant-phenotype (0/12 cases) in 12 cases of esophagitis. We found 10 cases (10/80 cases) of p53 IHC mutant-phenotype in 80 cases of low-grade dysplasia, and 158 cases (158/170 cases) of p53 IHC mutant-phenotype of high-grade lesions in 170 cases of high-grade dysplasia and early cancer based on the χ2 test results. We found statistically significant differences in p53 IHC mutant-phenotype between the high-grade squamous epithelial lesions and benign lesions. The sensitivity and specificity of p53 in detecting high-grade squamous epithelial lesions were 92.9% and 89.1%, respectively. The positive predictive value was 94.0%, and the negative predictive value was 87.2%. CONCLUSION: In this study, we found that p53 IHC had high sensitivity and specificity in detecting high-grade esophageal squamous epithelial lesions. Therefore, it has potential to be used as a routine item in pathological detection for auxiliary risk stratification of esophageal squamous epithelial lesions.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Humanos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Hiperplasia/diagnóstico , Hiperplasia/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Fenótipo
17.
ISA Trans ; 142: 702-715, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37481439

RESUMO

The difference in power demand and the driver's operation in various operation stages make the loader have the problem of low energy utilization. Changeable operating objects and drastically changing loads have exacerbated the difficulty of energy-saving research in different operating stages of loaders. Therefore, based on identifying the operation stage and analyzing the load characteristics under typical working conditions of the loader, this paper proposes a shovel-loading cooperative control strategy. Specifically, the Drag Reduction Insertion (DRI) in the shoveling stage is realized based on learning the driving intention. Based on different operation stages, the load characteristics of different materials for shovel-loading are deeply analyzed, and the prediction research of the power output characteristics of the power unit is carried out. The shovel-loading cooperative control solves the problem of the poor economy caused by different power requirements in different operation stages and significantly reduces the impact of the driver's operating experience.

18.
J Laparoendosc Adv Surg Tech A ; 33(9): 904-908, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37417990

RESUMO

Background: An aberrant vascular anatomy might present a technical pitfall for biliary atresia (BA) surgery. The purpose of this study was to report the rare cases and discuss the significance and management strategy for BA with an aberrant right hepatic artery (ARHA) by laparoscopic Kasai procedure in children. Methods: The subjects for this study were 10 consecutive type III BA patients with an ARHA who had laparoscopic Kasai procedure at our institute between January 2012 and August 2021. The common bile duct was mobilized between the right hepatic artery and the right branch of portal vein, and then lifted to the liver hilum. The fibrous cord was transected and then the laparoscopic Kasai was carried out. Results: All patients survived the laparoscopic Kasai without any intraoperative complications. The mean operative time was 235 minutes for each laparoscopic Kasai. The mean follow-up time was 32.6 months. The total and direct bilirubin dropped to normal within 4 months of surgery in 7 patients. One patient died of repeated cholangitis and liver failure 1 year after surgery. In the additional 2 patients the bilirubin levels dropped significantly after the surgery but elevated again because of repeated cholangitis and requiring ongoing observation and intermittent treatment. Conclusions: With the perfect laparoscopic skills, the common bile duct could be safely mobilized between the right hepatic artery and right branch of portal vein for the infants with type III BA associated with an ARHA, and laparoscopic Kasai could be carried out safely and successfully.


Assuntos
Atresia Biliar , Colangite , Laparoscopia , Lactente , Criança , Humanos , Atresia Biliar/cirurgia , Portoenterostomia Hepática/efeitos adversos , Artéria Hepática/cirurgia , Resultado do Tratamento , Laparoscopia/métodos , Colangite/etiologia , Bilirrubina , Estudos Retrospectivos
19.
ACS Appl Mater Interfaces ; 15(25): 31057-31066, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37317823

RESUMO

Anion exchange membrane (AEM) fuel cells have gained significant interest in recent years due to their promising applications in cost-effective and environmentally friendly energy conversion. Among various factors that affect their performance, water content plays an important role in the conductivity and stability of AEMs. However, the effect of the hydration level on the microstructure of AEMs and the correlation between the microstructure and macroconductivity have not been systematically investigated. In this work, four AEMs, quaternary ammonia polysulfone, quaternary ammonia poly(N-methyl-piperidine-co-p-terphenyl) (QAPPT), and bromoalkyl-tethered poly(biphenyl alkylene)s PBPA and PBPA-co-BPP, have been studied by atomic force microscopy and electrochemical impedance spectroscopy to elucidate the correlation between the humidity-dependent surface microstructure and macroconductivity of the AEMs. We obtained phase images by atomic force microscopy and identified hydrophilic and hydrophobic domains by fitting the distribution curve of phase images, which reasonably distinguishes hydrophilic domains from hydrophobic domains of the membrane surface, and thus, the surface hydrophilic area ratio and average size could be quantitatively analyzed. The conductivities of the membranes were then measured by electrochemical impedance spectroscopy at various humidities. The joint results from atomic force microscopy and electrochemical measurements help clarify the effect of the hydration level on the microphase separation and ionic conduction of the membranes.

20.
Nat Commun ; 14(1): 3536, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37321993

RESUMO

The solid-electrolyte interphase (SEI) plays crucial roles for the reversible operation of lithium metal batteries. However, fundamental understanding of the mechanisms of SEI formation and evolution is still limited. Herein, we develop a depth-sensitive plasmon-enhanced Raman spectroscopy (DS-PERS) method to enable in-situ and nondestructive characterization of the nanostructure and chemistry of SEI, based on synergistic enhancements of localized surface plasmons from nanostructured Cu, shell-isolated Au nanoparticles and Li deposits at different depths. We monitor the sequential formation of SEI in both ether-based and carbonate-based dual-salt electrolytes on a Cu current collector and then on freshly deposited Li, with dramatic chemical reconstruction. The molecular-level insights from the DS-PERS study unravel the profound influences of Li in modifying SEI formation and in turn the roles of SEI in regulating the Li-ion desolvation and the subsequent Li deposition at SEI-coupled interfaces. Last, we develop a cycling protocol that promotes a favorable direct SEI formation route, which significantly enhances the performance of anode-free Li metal batteries.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Lítio , Ouro , Análise Espectral Raman , Eletrólitos
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