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1.
Laryngoscope ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801129

RESUMO

OBJECTIVES: Vocal fold leukoplakia (VFL) is a precancerous lesion of laryngeal cancer, and its endoscopic diagnosis poses challenges. We aim to develop an artificial intelligence (AI) model using white light imaging (WLI) and narrow-band imaging (NBI) to distinguish benign from malignant VFL. METHODS: A total of 7057 images from 426 patients were used for model development and internal validation. Additionally, 1617 images from two other hospitals were used for model external validation. Modeling learning based on WLI and NBI modalities was conducted using deep learning combined with a multi-instance learning approach (MIL). Furthermore, 50 prospectively collected videos were used to evaluate real-time model performance. A human-machine comparison involving 100 patients and 12 laryngologists assessed the real-world effectiveness of the model. RESULTS: The model achieved the highest area under the receiver operating characteristic curve (AUC) values of 0.868 and 0.884 in the internal and external validation sets, respectively. AUC in the video validation set was 0.825 (95% CI: 0.704-0.946). In the human-machine comparison, AI significantly improved AUC and accuracy for all laryngologists (p < 0.05). With the assistance of AI, the diagnostic abilities and consistency of all laryngologists improved. CONCLUSIONS: Our multicenter study developed an effective AI model using MIL and fusion of WLI and NBI images for VFL diagnosis, particularly aiding junior laryngologists. However, further optimization and validation are necessary to fully assess its potential impact in clinical settings. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

2.
Am J Otolaryngol ; 45(4): 104342, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38703609

RESUMO

OBJECTIVE: To develop a multi-instance learning (MIL) based artificial intelligence (AI)-assisted diagnosis models by using laryngoscopic images to differentiate benign and malignant vocal fold leukoplakia (VFL). METHODS: The AI system was developed, trained and validated on 5362 images of 551 patients from three hospitals. Automated regions of interest (ROI) segmentation algorithm was utilized to construct image-level features. MIL was used to fusion image level results to patient level features, then the extracted features were modeled by seven machine learning algorithms. Finally, we evaluated the image level and patient level results. Additionally, 50 videos of VFL were prospectively gathered to assess the system's real-time diagnostic capabilities. A human-machine comparison database was also constructed to compare the diagnostic performance of otolaryngologists with and without AI assistance. RESULTS: In internal and external validation sets, the maximum area under the curve (AUC) for image level segmentation models was 0.775 (95 % CI 0.740-0.811) and 0.720 (95 % CI 0.684-0.756), respectively. Utilizing a MIL-based fusion strategy, the AUC at the patient level increased to 0.869 (95 % CI 0.798-0.940) and 0.851 (95 % CI 0.756-0.945). For real-time video diagnosis, the maximum AUC at the patient level reached 0.850 (95 % CI, 0.743-0.957). With AI assistance, the AUC improved from 0.720 (95 % CI 0.682-0.755) to 0.808 (95 % CI 0.775-0.839) for senior otolaryngologists and from 0.647 (95 % CI 0.608-0.686) to 0.807 (95 % CI 0.773-0.837) for junior otolaryngologists. CONCLUSIONS: The MIL based AI-assisted diagnosis system can significantly improve the diagnostic performance of otolaryngologists for VFL and help to make proper clinical decisions.


Assuntos
Inteligência Artificial , Laringoscopia , Leucoplasia , Prega Vocal , Humanos , Prega Vocal/diagnóstico por imagem , Prega Vocal/patologia , Laringoscopia/métodos , Masculino , Leucoplasia/diagnóstico , Leucoplasia/patologia , Feminino , Pessoa de Meia-Idade , Idoso , Diagnóstico por Computador/métodos , Aprendizado de Máquina , Diagnóstico Diferencial , Adulto , Algoritmos , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/diagnóstico por imagem
3.
J Cataract Refract Surg ; 50(6): 618-623, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38350234

RESUMO

PURPOSE: To test a cataract shadow projection theory and validate it by developing a deep learning algorithm that enables automatic and stable posterior polar cataract (PPC) screening using fundus images. SETTING: Department of Ophthalmology, Far Eastern Memorial Hospital, New Taipei, Taiwan. DESIGN: Retrospective chart review. METHODS: A deep learning algorithm to automatically detect PPC was developed based on the cataract shadow projection theory. Retrospective data (n = 546) with ultra-wide field fundus images were collected, and various model architectures and fields of view were tested for optimization. RESULTS: The final model achieved 80% overall accuracy, with 88.2% sensitivity and 93.4% specificity in PPC screening on a clinical validation dataset (n = 103). CONCLUSIONS: This study established a significant relationship between PPC and the projected shadow, which may help surgeons to identify potential PPC risks preoperatively and reduce the incidence of posterior capsular rupture during cataract surgery.


Assuntos
Algoritmos , Catarata , Aprendizado Profundo , Humanos , Estudos Retrospectivos , Catarata/diagnóstico , Fundo de Olho , Masculino , Feminino , Idoso , Pessoa de Meia-Idade
4.
RSC Adv ; 13(46): 32681-32693, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37936644

RESUMO

Aptamers have sparked significant interest in cell recognition because of their superior binding specificity and biocompatibility. Cell recognition can be mediated by targeting the major histocompatibility complex (MHC) that presents short peptides derived from intracellular antigens. Although numerous antibodies have demonstrated a specific affinity for the peptide-MHC complex, the number of aptamers that exhibit comparable characteristics is limited. Aptamers are usually selected from large libraries via the Systemic Evolution of Ligands by Exponential Enrichment (SELEX), an iterative process of selection and PCR amplification to enrich a pool of aptamers with high affinity. However, the success rate of aptamer identification is low, possibly due to the presence of complementary sequences or sequences rich in guanine and cytosine that are less accessible for primers. Here, we modified SELEX by employing systemic consecutive selections with minimal PCR amplification. We also modified the analysis by selecting aptamers that were identified in multiple selection rounds rather than those that are highly enriched. Using this approach, we were able to identify two aptamers with binding specificity to cells expressing the ovalbumin alloantigen as a proof of concept. These two aptamers were also discovered among the top 150 abundant candidates, despite not being highly enriched, by performing conventional SELEX. Additionally, we found that highly enriched aptamers tend to contain fractions of the primer sequence and have minimal target affinity. Candidate aptamers are easily missed in the conventional SELEX process. Therefore, our modification for SELEX may facilitate the identification of aptamers for more application in diverse biomedical fields. Significance: we modify the conventional method to improve the efficiency in the identification of the aptamer, a single strand of nucleic acid with binding specificity to the target molecule, showing as a proof of concept that this approach is particularly useful to select aptamers that can selectively bind to cells presenting a particular peptide by the major histocompatibility complex (MHC) on the cell surface. Given that cancer cells may express mutant peptide-MHC complexes that are distinct from those expressed by normal cells, this study sheds light on the potential application of aptamers to cancer cell targeting.

5.
Braz J Med Biol Res ; 56: e12638, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37493769

RESUMO

RNA interference (RNAi) treatment has been proven to be an important therapeutic approach in cancer based on downregulation of target-oncogenes, but its clinical efficacy still needs further investigation. LMP1 is usually presented by Epstein-Barr virus (EBV)-positive tumor cells like EBV-associated nasopharyngeal carcinoma (NPC) and acts as an oncogene in tumorigenesis. However, the mechanism of LMP1 as a proto-oncogene in nasopharyngeal carcinoma is still unclear. Two sequence-specific shRNAs 1 and 2 were designed to target the different nucleotide loci of EBV latent antigen LMP1 gene and a series of in vivo and in vitro experiments were performed to investigate the therapeutic effect of sequence-specific shRNAs targeting LMP1 and its related molecular mechanisms in EBV-positive NPC. LMP1-shRNA2 generated a truncated LMP1 mRNA and protein, whereas LMP1-shRNA1 completely blocked LMP1 mRNA and protein expression. Both LMP1-shRNAs inhibited the proliferation and migration of NPC cells overexpressing LMP1 (NPC-LMP1) as well as the NPC-associated myeloid-derived suppressor cell (MDSC) expansion in vitro. However, LMP1-shRNA2 maintained the immunogenicity of NPC-LMP1 cells, which provoked MHC-class I-dependent T cell recognition. LMP1-shRNAs inhibited tumor growth in nude mice but did not reach statistical significance compared to control groups, while the LDH nanoparticle loaded LMP1-shRNAs and the antigen-specific T cells induced by NPC-LMP1 cells treated with LMP1-shRNA2 significantly reduced tumor growth in vivo. LMP1-RNAi-based anti-tumor therapy could be a new hope for the clinical efficacy of RNAi treatment of tumors like NPC.


Assuntos
Carcinoma , Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Animais , Camundongos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/terapia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Carcinoma/metabolismo , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/metabolismo , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/terapia , Neoplasias Nasofaríngeas/metabolismo , Interferência de RNA , Camundongos Nus , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , RNA Mensageiro/metabolismo , Linhagem Celular Tumoral
6.
Heliyon ; 9(8): e18472, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37520946

RESUMO

Background: With age, people begin to experience deterioration in standing balance, especially when sensory input is suddenly removed or added. Here, we sought to explore the effects of age on postural performance and postural control strategies. Methods: The convenience sample consisted of 15 young, 10 middle-aged, and 14 elderly healthy adults. They were instructed to stand with their feet together in four randomly administered conditions involving visual input removal/addition and single-/dual-tasking. Dual-tasking involved continuous subtraction by 3s. Results: Postural sway displacement in the two older groups seemed larger than that in the younger group; however, neither the main effect of group (F2, 36 = 1.152, p = .327) nor the group × time interaction effect (F4, 27 = 0.229, p = .922) was significant. Greater stiffness of the lower leg muscles was observed in the vision-addition condition than in the vision-removal condition in only the elderly group (t13 = -2.755, p = .016). The dual-tasking condition resulted in smaller sway displacement (F1, 36 = 7.690, p = .009) and greater muscle stiffness (F1, 36 = 5.495, p = .025). In the vision-removal condition, the increase in muscle stiffness due to dual-tasking was significantly larger in the middle-aged (t9 = -3.736, p = .005) and elderly groups (t13 = -2.512, p = .026). Conclusions: In healthy older individuals, age-related changes were observed in control strategies used to maintain standing balance upon changes in visual input. The dual-task paradigm induced the use of an ankle-stiffening strategy in middle-aged and elderly adults.

7.
Braz. j. med. biol. res ; 56: e12638, 2023. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1447691

RESUMO

RNA interference (RNAi) treatment has been proven to be an important therapeutic approach in cancer based on downregulation of target-oncogenes, but its clinical efficacy still needs further investigation. LMP1 is usually presented by Epstein-Barr virus (EBV)-positive tumor cells like EBV-associated nasopharyngeal carcinoma (NPC) and acts as an oncogene in tumorigenesis. However, the mechanism of LMP1 as a proto-oncogene in nasopharyngeal carcinoma is still unclear. Two sequence-specific shRNAs 1 and 2 were designed to target the different nucleotide loci of EBV latent antigen LMP1 gene and a series of in vivo and in vitro experiments were performed to investigate the therapeutic effect of sequence-specific shRNAs targeting LMP1 and its related molecular mechanisms in EBV-positive NPC. LMP1-shRNA2 generated a truncated LMP1 mRNA and protein, whereas LMP1-shRNA1 completely blocked LMP1 mRNA and protein expression. Both LMP1-shRNAs inhibited the proliferation and migration of NPC cells overexpressing LMP1 (NPC-LMP1) as well as the NPC-associated myeloid-derived suppressor cell (MDSC) expansion in vitro. However, LMP1-shRNA2 maintained the immunogenicity of NPC-LMP1 cells, which provoked MHC-class I-dependent T cell recognition. LMP1-shRNAs inhibited tumor growth in nude mice but did not reach statistical significance compared to control groups, while the LDH nanoparticle loaded LMP1-shRNAs and the antigen-specific T cells induced by NPC-LMP1 cells treated with LMP1-shRNA2 significantly reduced tumor growth in vivo. LMP1-RNAi-based anti-tumor therapy could be a new hope for the clinical efficacy of RNAi treatment of tumors like NPC.

8.
Sensors (Basel) ; 22(15)2022 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35898000

RESUMO

In the context of behavior recognition, the emerging bed-exit monitoring system demands a rapid deployment in the ward to support mobility and personalization. Mobility means the system can be installed and removed as required without construction; personalization indicates human body tracking is limited to the bed region so that only the target is monitored. To satisfy the above-mentioned requirements, the behavior recognition system aims to: (1) operate in a small-size device, typically an embedded system; (2) process a series of images with narrow fields of view (NFV) to detect bed-related behaviors. In general, wide-range images are preferred to obtain a good recognition performance for diverse behaviors, while NFV images are used with abrupt activities and therefore fit single-purpose applications. This paper develops an NFV-based behavior recognition system with low complexity to realize a bed-exit monitoring application on embedded systems. To achieve effectiveness and low complexity, a queueing-based behavior classification is proposed to keep memories of object tracking information and a specific behavior can be identified from continuous object movement. The experimental results show that the developed system can recognize three bed behaviors, namely off bed, on bed and return, for NFV images with accuracy rates of 95~100%.


Assuntos
Hospitais , Reconhecimento Psicológico , Humanos , Monitorização Fisiológica/métodos
9.
J Chin Med Assoc ; 85(4): 431-437, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35125403

RESUMO

BACKGROUND: Oral squamous cell carcinoma (OSCC) is a type of malignancy characterized by high relapse and recurrence rates in the late stage despite optimal surgical intervention and postoperative chemoradiotherapy. Because the management of relapse following definitive treatment is challenging, accurate risk stratification is of clinical significance to improve treatment outcomes. Circular RNAs (circRNAs) are noncoding RNAs featured with cell-type specificity and high stability, owing to their circular structure, making these molecules excellent biomarkers for a variety of diseases. METHODS: The levels of hsa_circ_0000190 and 0001649 in plasma samples from 30 healthy controls and 66 OSCC patients were determined by droplet digital polymerase chain reaction. The same primer sets were used with PCR to examine the expression of these two circRNAs in cancerous and adjacent normal tissues. A receiver operating characteristics curve was generated to evaluate the diagnostic value. The Kaplan-Meier method with a log-rank test was used for survival analysis. RESULTS: We identified two circRNAs as potential biomarkers for OSCC, showing that the plasma level of hsa_circ_0000190 was significantly decreased in the late stage and marginally correlated with the development of second primary OSCC. We also found that the decreased plasma hsa_circ_0001649 was correlated with the recurrence and poor prognosis of patients. Additionally, we found that high plasma hsa_circ_0000190, but not hsa_circ_0001649, possibly predicted a better response of patients to induction chemotherapy. CONCLUSION: Our study demonstrated the potential of biomarkers in plasma to inform not just the tumor but the entire oral cavity, thereby offering a prediction for early recurrence and second primary OSCC. The plasma circRNAs remain valuable for OSCC, albeit the easy accessibility to the oral cavity.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Biomarcadores , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Humanos , Neoplasias Bucais/terapia , Recidiva Local de Neoplasia , RNA/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço
10.
J Integr Neurosci ; 19(3): 513-519, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33070532

RESUMO

"Tianma" (Gastrodia) and "gouteng" (Uncaria) are both widely used to treat cerebral ischemia. At the same time, "ezhu" (Curcuma longa) or turmeric, is derived from the dried roots of C. longa. It is a polyphenol known for its anti-inflammatory effects and its promotion of blood vessel endothelial function. This study explored the neuroprotective effects of a water extract of "tianma", "gouteng", and "ezhu" against ischemic injury. Flow cytometry analysis showed that Gastrodia, Uncaria, and Curcuma reduced the proportion of apoptotic cells in CoCl2 induced B35 (P = 0.0027) and SH-SY5Y (P = 0.0006) cell sample relative to the respective control group. Western blot indicated that Gastrodia, Uncaria, and Curcuma upregulated the expression of Bcl-2 and inversely downregulated Bax and Caspase-3 (P < 0.001). The infarct volume observed in the Gastrodia, Uncaria, and Curcuma group was also decreased compared with the control group (P < 0.05). Immunofluorescence detection revealed a lower expression of Caspase-7 in the Gastrodia, Uncaria, and Curcuma group than in the control group, while expression was negligible in the sham group. Gastrodia, Uncaria, and Curcuma confer neuroprotective effects in CoCl2 induced B35/SH-SY5Y cells and a rat model of ischemia by way of its anti-apoptotic effects.


Assuntos
Isquemia Encefálica/prevenção & controle , Medicamentos de Ervas Chinesas/administração & dosagem , Gastrodia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Extratos Vegetais/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Curcuma , Humanos , Ratos
11.
J Chin Med Assoc ; 83(10): 891-894, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32773584

RESUMO

As of April 15, 2020, the US Food and Drug Administration has granted emergency use authorization to a first saliva test for diagnosis of severe acute respiratory syndrome coronavirus 2 infection, the device developed by RUCDR Infinite Biologics laboratory, Rutgers University. A key feature that distinguishes the saliva-based test from nasopharyngeal or oropharyngeal (throat) swabs is that this kit allows self-collection and can spare healthcare professionals to be at risk during collecting nasopharyngeal or oropharyngeal samples, thereby preserving personal protective equipment for use in patient care rather than sampling and testing. Consequently, broader testing than the current methods of nasal or throat swabs will significantly increase the number of people screening, leading to more effective control of the spread of COVID-19. Nonetheless, a comparison of saliva-based assay with current swab test is needed to understand what and how we can benefit from this newly developed assay. Therefore, in this mini-review article, we aimed to summarize the current and emerging tools, focusing on diagnostic power of different clinical sampling and specimens.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Nasofaringe/virologia , Faringe/virologia , Pneumonia Viral/diagnóstico , Saliva/virologia , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico , Humanos , Pandemias , SARS-CoV-2 , Manejo de Espécimes/métodos
12.
Int J Mol Sci ; 22(1)2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33396303

RESUMO

Endoplasmic reticulum (ER) stress response is an adaptive program to cope with cellular stress that disturbs the function and homeostasis of ER, which commonly occurs during cancer progression to late stage. Late-stage cancers, mostly requiring chemotherapy, often develop treatment resistance. Chemoresistance has been linked to ER stress response; however, most of the evidence has come from studies that correlate the expression of stress markers with poor prognosis or demonstrate proapoptosis by the knockdown of stress-responsive genes. Since ER stress in cancers usually persists and is essentially not induced by genetic manipulations, we used low doses of ER stress inducers at levels that allowed cell adaptation to occur in order to investigate the effect of stress response on chemoresistance. We found that prolonged tolerable ER stress promotes mesenchymal-epithelial transition, slows cell-cycle progression, and delays the S-phase exit. Consequently, cisplatin-induced apoptosis was significantly decreased in stress-adapted cells, implying their acquisition of cisplatin resistance. Molecularly, we found that proliferating cell nuclear antigen (PCNA) ubiquitination and the expression of polymerase η, the main polymerase responsible for translesion synthesis across cisplatin-DNA damage, were up-regulated in ER stress-adaptive cells, and their enhanced cisplatin resistance was abrogated by the knockout of polymerase η. We also found that a fraction of p53 in stress-adapted cells was translocated to the nucleus, and that these cells exhibited a significant decline in the level of cisplatin-DNA damage. Consistently, we showed that the nuclear p53 coincided with strong positivity of glucose-related protein 78 (GRP78) on immunostaining of clinical biopsies, and the cisplatin-based chemotherapy was less effective for patients with high levels of ER stress. Taken together, this study uncovers that adaptation to ER stress enhances DNA repair and damage tolerance, with which stressed cells gain resistance to chemotherapeutics.


Assuntos
Adaptação Fisiológica , Cisplatino/farmacologia , Reparo do DNA , DNA Polimerase Dirigida por DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos , Estresse do Retículo Endoplasmático , Neoplasias Bucais/tratamento farmacológico , Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Dano ao DNA , Replicação do DNA , DNA Polimerase Dirigida por DNA/genética , Chaperona BiP do Retículo Endoplasmático , Humanos , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Células Tumorais Cultivadas
13.
J Nanosci Nanotechnol ; 19(4): 2108-2115, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486953

RESUMO

A stability analyser and a rheometer were used to study the effects of Tween 85 (polyoxyethylene sorbitan trioleate) on the dispersion properties of nano-aluminium/JP-10 (exo-tetrahydrodicyclopentadiene) suspensions. Results show that the addition of Tween 85 can effectively improve the stability of two-phase suspensions by hindering particle aggregation and reduce the viscosity of a system. The surface characteristics of the zeta potential and the contact angle were measured. The dispersion of the suspensions was improved by Tween 85 mainly by enhancing the steric hindrance of particles. The adsorbed particles obtained in JP-10 with different Tween 85 concentrations were analysed via scanning electron microscopy and Fourier transform infrared spectroscopy to explore the adsorption behaviour of Tween 85 molecules on the surface of aluminium particles and to confirm that Tween 85 formed an adsorption layer on the particle surface. Thermogravimetric analysis indicated that the adsorption amount of Tween 85 increased with its concentration in JP-10. The roughness analysis of the surface of adsorbed particles was measured via atomic force microscopy to characterise the thickness of the adsorption layer. The results showed that Tween 85 molecules formed an irregular adsorption layer on the particle surface, and an increase in the concentration of Tween 85 in JP-10 increased the thickness of the adsorption layer.

14.
ACS Appl Mater Interfaces ; 7(51): 28166-76, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26462014

RESUMO

In this study, a jumbo silicon/silicon carbide (Si/SiC) composite (JSC), a novel anode material source, was extracted from solar power industry cutting waste and used as a material for lithium-ion batteries (LIBs), instead of manufacturing the nanolized-Si. Unlike previous methods used for preventing volume expansion and solid electrolyte interphase (SEI), the approach proposed here simply entails applying surface modification to JSC-based electrodes by using nitrogen-atmospheric pressure plasma jet (N-APPJ) treatment process. Surface organic bonds were rearranged and N-doped compounds were formed on the electrodes through applying different plasma treatment durations, and the qualitative examinations of before/after plasma treatment were identified by X-ray photoelectron spectroscopy (XPS) and electron probe microanalyzer (EPMA). The surface modification resulted in the enhancement of electrochemical performance with stable capacity retention and high Coulombic efficiency. In addition, depth profile and scanning electron microscope (SEM) images were executed to determine the existence of Li-N matrix and how the nitrogen compounds change the surface conditions of the electrodes. The N-APPJ-induced rapid surface modification is a major breakthrough for processing recycled waste that can serve as anode materials for next-generation high-performance LIBs.

15.
Small ; 11(19): 2314-22, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-25641716

RESUMO

Silicon (Si) has been perceived as a promising anode material for lithium-ion batteries for decades due to its superior theoretical capacity, environmental benignity, and earth abundance. To accommodate the drastic volume expansion during lithiation, which is the primary drawback leading to poor cycling life, a novel structural design via fabricating the Marimo-like carbon nanotubes frameworks with silicon nanoparticle (SiNP) filling in internal space has been developed. This facile fabrication procedure involves an in-spaced polymerization process through ex situ polymerization, using pyrrole monomers with a soft organic template in which well-dispersed SiNPs are present. Carbonization post-treatment is then performed to construct rigid conductive networks. The thus-fabricated 3D Marimo-like hybrid structure exhibits a remarkably improved electrochemical performance compared with that of the simple ball-milling method, which mainly originates from their structural advantages, including the built-in buffer spaces and the robust line-to-line contact mode between the components. The state-of-the-art structure exhibits an optimal high-rate capability (422 mAh g(-1) at a current rate of 2 A g(-1)) and long cycling stability (916 mAh g(-1) for 200th cycles at a current rate of 0.2 A g(-1)) and achieves the requirements for industrial production with the facile and cost-effective synthetic approach.

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