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1.
J Neural Eng ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38754410

RESUMEN

Upper limb loss can profoundly impact an individual's quality of life, posing challenges to both physical capabilities and emotional well-being. To restore limb function by decoding electromyography (EMG) signals, in this paper, we present a novel deep prototype learning method for accurate and generalizable EMG-based gesture classification. Existing methods suffer from limitations in generalization across subjects due to the diverse nature of individual muscle responses, impeding seamless applicability in broader populations. By leveraging deep prototype learning, we introduce a method that goes beyond direct output prediction. Instead, it matches new EMG inputs to a set of learned prototypes and predicts the corresponding labels. This novel methodology significantly enhances the model's classification performance and generalizability by discriminating subtle differences between gestures, making it more reliable and precise in real-world applications. Our experiments on four Ninapro datasets suggest that our deep prototype learning classifier outperforms state-of-the-art methods in terms of intra-subject and inter-subject classification accuracy in gesture prediction. The results from our experiments validate the effectiveness of the proposed method and pave the way for future advancements in the field of EMG gesture classification for upper limb prosthetics.

2.
J Cancer ; 15(10): 3152-3153, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38706919

RESUMEN

[This corrects the article DOI: 10.7150/jca.53385.].

3.
Int J Biol Macromol ; 269(Pt 2): 131885, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38688340

RESUMEN

Ag-doped Cu2O immobilized carbon beads (Ag/Cu2O@CB) based composite photocatalysts have been prepared for the removal of levofloxacin, an antibiotic, from water. The photocatalysts were prepared by the processes of chemical reduction and in-situ solid-phase precipitation. The composite photocatalyst was characterized by a porous and interconnected network structure. Ag nanoparticles were deposited on Cu2O particles to develop a metal-based semiconductor to increase the catalytic efficiency of the system and the separation efficiency of the photogenerated carriers. Cellulose-derived carbon beads (CBs) can also be used as electron storage libraries which can capture electrons released from the conduction band of Cu2O. The results revealed that the maximum catalytic degradation efficiency of the composite photocatalyst for the antibiotic levofloxacin was 99.02 %. The Langmuir-Hinshelwood model was used to study the reaction kinetics, and the process of photodegradation followed first-order kinetics. The maximum apparent rate was recorded to be 0.0906 min-1. The mass spectrometry technique showed that levofloxacin degraded into carbon dioxide and water in the presence of the photocatalyst. The results revealed that the easy-to-produce photocatalyst was stable and efficient in levofloxacin removing.

4.
GM Crops Food ; 15(1): 118-129, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38564429

RESUMEN

Soybean is one of the important oil crops and a major source of protein and lipids. Drought can cause severe soybean yields. Dehydrin protein (DHN) is a subfamily of LEA proteins that play an important role in plant responses to abiotic stresses. In this study, the soybean GmDHN9 gene was cloned and induced under a variety of abiotic stresses. Results showed that the GmDHN9 gene response was more pronounced under drought induction. Subcellular localization results indicated that the protein was localized in the cytoplasm. The role of transgenic Arabidopsis plants in drought stress response was further studied. Under drought stress, the germination rate, root length, chlorophyll, proline, relative water content, and antioxidant enzyme content of transgenic Arabidopsis thaliana transgenic genes were higher than those of wild-type plants, and transgenic plants contained less O2-, H2O2 and MDA contents. In short, the GmDHN9 gene can regulate the homeostasis of ROS and enhance the drought resistance of plants.


Asunto(s)
Arabidopsis , Arabidopsis/genética , Resistencia a la Sequía , Glycine max/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Peróxido de Hidrógeno/metabolismo , Estrés Fisiológico/genética , Sequías , Plantas Modificadas Genéticamente/metabolismo , Regulación de la Expresión Génica de las Plantas
5.
Org Biomol Chem ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38623736

RESUMEN

Herein, we report a visible light-enabled radical trihalomethylation/cyano-migration/carbonylation cascade reaction of 2-hydroxy-2-hex-5-enenitrile with CX3SO2Cl as the CX3-source (X = F, Cl) to obtain 5-oxo-2-(2,2,2-trihaloethyl)pentanenitrile compounds in the absence of a photocatalyst, transition metal and base. This reaction system is also effective to convert (benzo[d]thiazol-2-yl)-pent-4-enol to the corresponding 4-(benzo[d]thiazol-2-yl)-6,6,6-trihalo-hexanone products. These reactions occur under mild conditions, tolerate a wide range of functional groups, and provide alternative approaches for the 1,2-bifunctionalization reaction of unactivated olefins.

6.
Anim Sci J ; 95(1): e13944, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38549501

RESUMEN

The objective of this study was to investigate the effects of two different organic selenium (Se) supplements, selenomethionine (Se-Met) and selenohomolanthionine (Se-Hlan), on the serum biochemical parameters and Se status of dairy cows. Different dietary Se supplementation treatments were set as follows: a control group (CON, adding sodium selenite at 0.3 mg Se/kg dry matter [DM]), 0.3 and 0.5 Se-Met (adding Se-Met at 0.3 and 0.5 mg Se/kg DM, respectively), as well as 0.3 and 0.5 Se-Hlan (adding Se-Hlan at 0.3 and 0.5 mg Se/kg DM, respectively). The experiment lasted 8 weeks. The serum measurements showed that both organic Se treatments resulted in higher uric acid than CON. Se-Met produced higher aspartate aminotransferase, glucose, urea, low-density lipoprotein cholesterol, and lactate dehydrogenase than Se-Hlan. Regarding the Se status, the highest milk Se values appeared in 0.5 Se-Met, with intermediate values in 0.3 Se-Met and 0.5 Se-Hlan, whereas the highest and lowest serum Se levels were presented in 0.5 Se-Met and 0.3 Se-Hlan, respectively. Our results suggest that Se-Hlan was not as efficient in boosting serum or milk Se as Se-Met and differences in serum biomarkers between Se-Met and Se-Hlan may be associated with distinct metabolic pathways for different forms of organic Se.


Asunto(s)
Selenio , Femenino , Bovinos , Animales , Suplementos Dietéticos , Leche/metabolismo , Selenometionina/metabolismo , Alimentación Animal/análisis , Biomarcadores/metabolismo , Dieta/veterinaria
7.
Eur J Nucl Med Mol Imaging ; 51(6): 1651-1661, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38182838

RESUMEN

PURPOSE: MRI-negative children with focal cortical dysplasia type II (FCD II) are one of the most challenging cases in surgical epilepsy management. We aimed to utilize quantitative positron emission tomography (QPET) analysis to complement [18F]SynVesT-1 and [18F]FDG PET imaging and facilitate the localization of epileptogenic foci in pediatric MRI-negative FCD II patients. METHODS: We prospectively enrolled 17 MRI-negative children with FCD II who underwent [18F]SynVesT-1 and [18F]FDG PET before surgical resection. The QPET scans were analyzed using statistical parametric mapping (SPM) with respect to healthy controls. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC) of [18F]SynVesT-1 PET, [18F]FDG PET, [18F]SynVesT-1 QPET, and [18F]FDG QPET in the localization of epileptogenic foci were assessed. Additionally, we developed a multivariate prediction model based on dual trace PET/QPET assessment. RESULTS: The AUC values of [18F]FDG PET and [18F]SynVesT-1 PET were 0.861 (sensitivity = 94.1%, specificity = 78.2%, PPV = 38.1%, NPV = 98.9%) and 0.908 (sensitivity = 82.4%, specificity = 99.2%, PPV = 93.3%, NPV = 97.5%), respectively. [18F]FDG QPET showed lower sensitivity (76.5%) and NPV (96.6%) but higher specificity (95.0%) and PPV (68.4%) than visual assessment, while [18F]SynVesT-1 QPET exhibited higher sensitivity (94.1%) and NPV (99.1%) but lower specificity (97.5%) and PPV (84.2%). The multivariate prediction model had the highest AUC value (AUC = 0.996, sensitivity = 100.0%, specificity = 96.6%, PPV = 81.0%, NPV = 100%). CONCLUSIONS: The multivariate prediction model based on [18F]SynVesT-1 and [18F]FDG PET/QPET assessments holds promise in noninvasively identifying epileptogenic regions in MRI-negative children with FCD II. Furthermore, the combination of visual assessment and QPET may improve the sensitivity and specificity of diagnostic tests in localizing epileptogenic foci and achieving a preferable surgical outcome in MRI-negative FCD II.


Asunto(s)
Epilepsia , Fluorodesoxiglucosa F18 , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Humanos , Niño , Masculino , Femenino , Tomografía de Emisión de Positrones/métodos , Preescolar , Adolescente , Malformaciones del Desarrollo Cortical de Grupo I/diagnóstico por imagen , Displasia Cortical Focal
8.
Artículo en Inglés | MEDLINE | ID: mdl-38261479

RESUMEN

Integrating information from vision and language modalities has sparked interesting applications in the fields of computer vision and natural language processing. Existing methods, though promising in tasks like image captioning and visual question answering, face challenges in understanding real-life issues and offering step-by-step solutions. In particular, they typically limit their scope to solutions with a sequential structure, thus ignoring complex inter-step dependencies. To bridge this gap, we propose a graph-based approach to vision-language problem solving. It leverages a novel integrated attention mechanism that jointly considers the importance of features within each step as well as across multiple steps. Together with a graph neural network method, this attention mechanism can be progressively learned to predict sequential and non-sequential solution graphs depending on the characterization of the problem-solving process. To tightly couple attention with the problem-solving procedure, we further design new learning objectives with attention metrics that quantify this integrated attention, which better aligns visual and language information within steps, and more accurately captures information flow between steps. Experimental results on VisualHow, a comprehensive dataset of varying solution structures, show significant improvements in predicting steps and dependencies, demonstrating the effectiveness of our approach in tackling various vision-language problems.

9.
Eur J Nucl Med Mol Imaging ; 51(2): 369-379, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37759096

RESUMEN

PURPOSE: PD-L1 PET imaging, as a non-invasive procedure, can perform a real-time, dynamic and quantitative analysis of PD-L1 expression at tumor sites. In this study, we developed a novel peptide-based PET tracer, [68 Ga]Ga-AUNP-12, for preclinical and first-of-its-kind imaging of PD-L1 expression in patients. METHODS: Radiosynthesis of [68 Ga]Ga-AUNP-12 was conducted. Assays for cellular uptake and binding were conducted on the PANC02, CT26, and B16F10 cell lines. Preclinical models were used to investigate its biodistribution, imaging capacity, and pharmacokinetics. Furthermore, interferon-γ (IFN-γ) was used for development of an animal model with high PD-L1 expression for targeted PET imaging and efficacy evaluation of PD-L1 blocking therapy. In healthy volunteers and cancer patients, the PD-L1 imaging, radiation dosimetry, safety, and biodistribution were further evaluated. RESULTS: In vitro and in vivo animal studies showed that [68 Ga]Ga-AUNP-12 PET imaging displayed a high specificity in evaluating PD-L1 expression. The radiochemical yield of [68 Ga]Ga-AUNP-12 was 71.7 ± 8.2%. Additionally, its molar activity and radiochemical purity were satisfactory. The B16F10 tumor was visualized with the tumor uptake of 6.86 ± 0.71% ID/g and tumor-to-muscle ratio of 6.83 ± 0.36 at 60 min after [68 Ga]Ga-AUNP-12 injection. Furthermore, [68 Ga]Ga-AUNP-12 PET imaging could sensitively detect the PD-L1 dynamic changes in CT26 tumor xenograft models regulated by IFN-γ treatment, and correspondingly can effectively guide immunotherapy. Regarding radiation dosimetry, [68 Ga]Ga-AUNP-12 is safe for human use. The first human study found that [68 Ga]Ga-AUNP-12 can be rapidly cleared from blood and other nonspecific organs through the kidney excretion, leading to form a clear imaging contrast in the clinical framework. The specificity of [68 Ga]Ga-AUNP-12 was validated and tumor uptake strongly correlated with the high PD-L1 expression in patients with lung adenocarcinoma and oesophageal squamous cell carcinoma (OSCC). CONCLUSION: [68 Ga]Ga-AUNP-12 was successfully developed as a PD-L1-specific PET imaging tracer in preclinical and first-in-human studies.


Asunto(s)
Radioisótopos de Galio , Neoplasias , Humanos , Antígeno B7-H1/metabolismo , Línea Celular Tumoral , Neoplasias/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Radiofármacos/farmacocinética , Distribución Tisular
10.
Clin Nucl Med ; 49(2): 180-181, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38049966

RESUMEN

ABSTRACT: A 54-year-old man presented with a 2-month history of urination disturbances. Serum prostate-specific antigen level was 4.96 ng/mL, and a possibility of benign prostate hyperplasia was raised by outside medical CT. Histopathology revealed adenosquamous carcinoma. Staging workup showed large areas of high PSMA uptake and focal intense hypermetabolism in the prostate, multiple lymphatics, bone, and pulmonary heterogenic metastases on 68 Ga-PSMA and 18 F-FDG PET/CT imaging.


Asunto(s)
Carcinoma Adenoescamoso , Neoplasias de la Próstata , Masculino , Humanos , Persona de Mediana Edad , Próstata/patología , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Fluorodesoxiglucosa F18 , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Carcinoma Adenoescamoso/diagnóstico por imagen , Carcinoma Adenoescamoso/patología
11.
BMC Gastroenterol ; 23(1): 400, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37978445

RESUMEN

BACKGROUND: Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease characterized by inflammation of the interlobular bile ducts. Ursodeoxycholic acid (UDCA) is the only FDA approved first-line therapy for PBC, but up to 40% of patients with PBC have an incomplete response to UDCA. Neutrophil-to-lymphocyte (NLR) has been used to predict prognosis in various liver diseases. There is limited evidence on the treatment response to UDCA in PBC patients. Our study aimed to evaluate the relationship between NRL and the response to UDCA treatment in PBC patients. METHODS: A total of 257 primary biliary cholangitis (PBC) patients treated with UDCA (13-15 mg/kg/d) were enrolled in this retrospective study. The response to treatment was evaluated based on alkaline phosphatase levels ≤1.67 times the upper limit of the normal value after 12 months of UDCA treatment. Multivariable logistic regression analysis was performed to investigate the association between NLR at baseline and the response to 12 months of UDCA treatment after adjusting for important confounding variables. The stability of the results was evaluated by unadjusted and adjusted models. RESULTS: The results of multiple regression analysis showed that NLR at baseline was positively associated with the nonresponse to UDCA treatment after adjustments for potential confounders (age, sex, BMI, hypertension, arterial plaque, thyroid disease, jaundice, albumin, globulin, total bile acid, ALP, GGT, LDLC, total cholesterol, hemoglobin, and APTT) (OR = 1.370, 95% CI 1.066-1.761). These results reveal that NLR is an independent risk factor for UDCA treatment nonresponse. CONCLUSIONS: Our results suggest that PBC patients with a high NLR had a worse response to UDCA therapy.


Asunto(s)
Cirrosis Hepática Biliar , Ácido Ursodesoxicólico , Humanos , Ácido Ursodesoxicólico/uso terapéutico , Ácido Ursodesoxicólico/efectos adversos , Estudios Retrospectivos , Cirrosis Hepática Biliar/tratamiento farmacológico , Cirrosis Hepática Biliar/complicaciones , Colagogos y Coleréticos/uso terapéutico , Neutrófilos , Resultado del Tratamiento
12.
Cancer Imaging ; 23(1): 81, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37667341

RESUMEN

BACKGROUND: The prostate-specific antigen (PSA) has been widely used in screening and early diagnosis of prostate cancer (PCa). However, in the PSA grey zone of 4-10 ng/ml, the sensitivity and specificity for diagnosing PCa are limited, resulting in considerable number of unnecessary and invasive prostate biopsies, which may lead to potential overdiagnosis and overtreatment. We aimed to predict clinically significant PCa (CSPCa) by combining the maximal standardized uptake value (SUVmax) based on 68Ga­PSMA PET/CT and clinical indicators in men with gray zone PSA levels. METHODS: 81 patients with suspected PCa based on increased serum total PSA (TPSA) levels of 4 - 10 ng/mL who underwent transrectal ultrasound/magnetic resonance imaging (MRI)/PET fusion-guided biopsy were enrolled. Among them, patients confirmed by histopathology were divided into the CSPCa group and the non-CSPCa group, and data on PSA concentration, prostate volume (PV), PSA density (PSAD), free PSA (FPSA)/TPSA, Prostate Imaging-Reporting and Data System version 2.1 (PI-RADS v2.1) score, 68Ga-PSMA PET/CT imaging evaluation results and SUVmax were compared. Multivariate logistic regression analysis was performed to identify the independent predictors for CSPCa, thereby establishing a predictive model based on SUVmax that was evaluated by analyzing the receiver operating characteristic (ROC) curve and decision curve analysis. RESULTS: Compared to non-CSPCa, CSPCa patients had smaller PVs (median, 31.40 mL), lower FPSA/TPSA (median, 0.12), larger PSADs (median, 0.21 ng/mL2) and higher PI-RADS scores (P < 0.05). The prediction model comprising 68Ga-PSMA PET/CT maximal standardized uptake value, PV and FPSA/TPSA had the highest AUC of 0.927 compared with that of other predictors alone (AUCs of 0.585 for PSA, 0.652 for mpMRI and 0.850 for 68Ga-PSMA PET/CT). The diagnostic sensitivity and specificity of the prediction model were 86.21% and 86.54%, respectively. CONCLUSION: Given the low diagnostic accuracy of regular PSA tests, a new prediction model based on the 68Ga-PSMA PET/CT SUVmax, PV and FPSA/TPSA was developed and validated, and this model could provide a more satisfactory predictive accuracy for CSPCa. This study provides a noninvasive prediction model with high accuracy for the diagnosis of CSPCa in the PSA gray zone, thus may be better avoiding unnecessary biopsy procedures.


Asunto(s)
Antígeno Prostático Específico , Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Imagen por Resonancia Magnética , Biopsia Guiada por Imagen
13.
Artículo en Inglés | MEDLINE | ID: mdl-37461343

RESUMEN

BACKGROUND: Liver cirrhosis is one of the leading causes of decreased life expectancy worldwide. However, the molecular mechanisms underlying liver cirrhosis remain unclear. In this study, we performed a comprehensive analysis using transcriptome and metabolome sequencing to explore the genes, pathways, and interactions associated with liver cirrhosis. METHODS: We performed transcriptome and metabolome sequencing of blood samples from patients with cirrhosis and healthy controls (1:1 matched for sex and age). We validated the differentially expressed microRNA (miRNA) and mRNAs using real-time quantitative polymerase chain reaction. RESULTS: For transcriptome analysis, we screened for differentially expressed miRNAs and mRNAs, analyzed mRNAs to identify possible core genes and pathways, and performed co-analysis of miRNA and mRNA sequencing results. In terms of the metabolome, we screened five pathways that were substantially enriched in the differential metabolites. Next, we identified the metabolites with the most pronounced differences among these five metabolic pathways. We performed receiver operating characteristic (ROC) curve analysis of these five metabolites to determine their diagnostic efficacy for cirrhosis. Finally, we explored possible links between the transcriptome and metabolome. CONCLUSION: Based on sequencing and bioinformatics, we identified miRNAs and genes that were differentially expressed in the blood of patients with liver cirrhosis. By exploring pathways and disease-specific networks, we identified unique biological mechanisms. In terms of metabolomes, we identified novel biomarkers and explored their diagnostic efficacy. We identified possible common pathways in the transcriptome and metabolome that could serve as candidates for further studies.

14.
Chem Asian J ; 18(14): e202300330, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37300365

RESUMEN

A direct protocol for Rh-catalyzed C-H amidation of ferrocenes in a ball mill using dioxazolones as the amide source under solvent-free conditions was developed. The corresponding ortho-aminated products were formed in 3 hours and the yields were up to 99% in the absence of base. This method could be a typically sustainable and environmental-friendly alternative method to traditional methodologies, with the advantages of wide substrate range, good functional group tolerance and gram-scale synthesis.

15.
Org Biomol Chem ; 21(25): 5185-5188, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37317819

RESUMEN

A KOH-promoted cascade C-Cl bond activation and amidation of trichloromethyl aromatic compounds with formamides using water as a solvent has been developed. This methodology suggested an alternative synthetic approach for the synthesis of aryl amide compounds in the absence of catalysts, additives and organic solvents. In addition, the yields of gram-scale reactions are good and provide a basis for synthetic application.

16.
Neural Plast ; 2023: 1863686, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37274448

RESUMEN

Methods: A pilot double-blind and randomized clinical trial. Ninety-one subjects with subacute stroke were treated with cathodal/sham stimulation tDCS based on CGR (physiotherapy 40 min/d and occupational therapy 20 min/d) once daily for 20 consecutive working days. Computer-based stratified randomization (1 : 1) was employed by considering age and sex, with concealed assignments in opaque envelopes to ensure no allocation errors after disclosure at the study's end. Patients were evaluated at T0 before treatment, T1 immediately after the posttreatment assessment, and T2 assessment one month after the end of the treatment. The primary outcome index was assessed: lower limb Fugl-Meyer motor score (FMA-LE); secondary endpoints were other gait assessment and relevant stroke scale assessment. Results: Patients in the trial group performed significantly better than the control group in all primary outcome indicators assessed posttreatment T1 and at follow-up T2: FMA-LE outcome indicators between the two groups in T1 (P = 0.032; effect size 1.00, 95% CI: 0.00 to 2.00) and FMA-LE outcome indicators between the two groups in T2 (P = 0.010; effect size 2.00, 95% CI: 1.00 to 3.00). Conclusion: In the current pilot study, ctDCS plus CGR was an effective treatment modality to improve lower limb motor function with subacute stroke. The effectiveness of cathodal tDCS in poststroke lower limb motor dysfunction is inconclusive. Therefore, a large randomized controlled trial is needed to verify its effectiveness.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Estimulación Transcraneal de Corriente Directa , Humanos , Proyectos Piloto , Recuperación de la Función , Accidente Cerebrovascular/terapia , Extremidad Inferior , Resultado del Tratamiento , Extremidad Superior
17.
Clin Nucl Med ; 48(4): 348-350, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36800250

RESUMEN

ABSTRACT: Malignant peritoneal mesothelioma is a rare malignancy that may manifest as extraperitoneal metastasis. We describe the findings of 68 Ga-FAPI and 18 F-FDG PET/CT in a case of malignant peritoneal mesothelioma with widespread muscle metastasis in a butterfly-shaped distribution pattern. We found that FDG and FAPI uptake in the peritoneal tumor and its spread were inhomogeneous. Notably, 68 Ga-FAPI PET/CT more clearly showed relevant lesions compared with 18 F-FDG PET/CT.


Asunto(s)
Mesotelioma Maligno , Neoplasias Peritoneales , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Fluorodesoxiglucosa F18 , Músculos
18.
Small ; 19(10): e2207745, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36650988

RESUMEN

Vertical graphene (VG) arrays show exposed sharp edges, ultra-low electrical resistance, large surface-to-volume ratio, and low light reflectivity, thus having great potential in emerging applications, including field emission, sensing, energy storage devices, and stray light shields. Although plasma enhanced chemical vapor deposition (PECVD) is regarded as an effective approach for the synthesis of VG, it is still challenging to increase the growth rate and height of VG arrays simultaneously. Herein, a fluorobenzene and water-assisted method to rapidly grow VG arrays in an electric field-assisted PECVD system is developed. Fluorobenzene-based carbon sources are used to produce highly electronegative fluorine radicals to accelerate the decomposition of methanol and promote the growth of VG. Water is applied to produce hydroxyl radicals in order to etch amorphous carbon and accelerate the VG growth. The fastest growth rate can be up to 15.9 µm h-1 . Finally, VG arrays with a height of 144 µm are successfully synthesized at an average rate of 14.4 µm h-1 . As a kind of super black material, these VG arrays exhibit an ultra-low reflectance of 0.25%, showing great prospect in stray light shielding.

19.
Carbohydr Polym ; 304: 120502, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36641192

RESUMEN

Recyclable and degradable supercapacitors have promising applications for a sustainable energy storage industry. Herein, we prepare a dual-physical crosslinking (DP) carboxymethyl cellulose (CMC) hydrogel with high-toughness, healability, and electric conductivity by integrating abundant ions into the matrix. The prepared hydrogel displays a maximum compressive fracture stress of 4.42 MPa, fast healing in five seconds, and full degradation within eight days. Moreover, the fabricated supercapacitor shows high specific capacitance (309 F g-1) and volumetric capacitance (2.60 F cm-3). The supercapacitor achieves a healing efficiency of 93.9 % after five cuttings, and exhibits a cycling stability of 84.6 % capacitance retention after 1000 cycles. These merits ensure that the all-cellulose-based supercapacitor can operate in case of sudden collision and deformation, which contribute to reducing the environmental hazards from supercapacitor's preparation to its abandonment.


Asunto(s)
Carboximetilcelulosa de Sodio , Electrólitos , Celulosa , Capacidad Eléctrica , Hidrogeles
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