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1.
Small ; : e2401892, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38794995

RESUMO

Inorganic solid-state electrolytes have attracted enormous attention due to their potential safety, increased energy density, and long cycle-life benefits. However, their application in solid-state batteries is limited by unstable electrode-electrolyte interface, poor point-to-point physical contact, and low utilization of metallic anodes. Herein, interfacial engineering based on sodium (Na)-conductive polymeric solid-state interfacial adhesive is studied to improve interface stability and optimize physical contacts, constructing a robust organic-rich solid electrolyte interphase layer to prevent dendrite-induced crack propagation and security issues. The interfacial adhesive strategy significantly increases the room-temperature critical current density of inorganic Na-ion conductors from 0.8 to 3.2 mA cm-2 and markedly enhances the cycling performance of solid-state batteries up to 500 cycles, respectively. Particularly, the Na3V2(PO4)3-based full solid-state batteries with high cathode loading of 10.16 mg cm-2 also deliver an excellent cycling performance, further realizing the stable operation of solid-state laminated pouch cells. The research provides fundamental perspectives into the role of interfacial chemistry and takes the field a step closer to realizing practical solid-state batteries.

2.
Small ; : e2311086, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459647

RESUMO

Despite the low competitive cost and high theoretical capacity of lithium-sulfur (Li-S) batteries, their practical application is severely hindered by the lithium polysulfide (LiPS) shuttling and low conversion efficiency. Herein, the electronic structure of hollow Titanium dioxide nanospheres is tunned by single Iron atom dopants that can cooperatively enhance LiPS absorption and facilitate desired redox reaction in practical Li-S batteries, further suppressing the notorious shuttle effect, which is consistent with theoretical calculations and in situ UV/vis investigation. The obtained electrode with massive active sites and lower energy barrier for sulfur conversions exhibits exceptional cycling stability after 500 cycles and high capacity under the sulfur loading of 10.53 mg cm-2 . In particular, an Ah-level Li-S pouch cell is fabricated, further demonstrating that the synthetic strategy based on atomic-level design offers a promising route toward practical high-energy-density Li-S batteries.

3.
Colloids Surf B Biointerfaces ; 231: 113537, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37776773

RESUMO

Periosteum, the thin layer covering adjacent to bone containing specific architecture, is important for functional bone regeneration and remodeling. Synthetic periosteum investigated presently lacks the resemblance of natural periosteum, suffering from poor mechanical strength and cell attachment. Here, we report a newly-developed biomimetic film to function as synthetic periosteum. Based on poly(ε-caprolactone) (PCL), where surface wettability of the synthetic periosteum is enhanced by microtantalum (mTa) particle blending and after a cold drawing process, further obtains topographical anisotropy without any involvement of solvent. This new blend shows mechanical enhancement over pure PCL, with yield stress and elastic strain approaching the natural periosteum. A distinct degradation mechanism is proposed for the blend, and by seeding with mouse calvarial preosteoblasts, cell proliferation is promoted on surface of the drawn PCL but delayed on the mTa-blended PCL. However, cell mineralization is accelerated on the mTa-blended surface. This is less on the drawn PCL. The synergistical integration of cellular proliferation, alignment and osteogenic enhancement suggest that the cold drawn PCL/Ta blend has unique potential for developing into a synthetic periosteum and other tissue-engineering products.


Assuntos
Periósteo , Poliésteres , Animais , Camundongos , Engenharia Tecidual , Osteogênese , Alicerces Teciduais
4.
Cancer Manag Res ; 14: 1293-1302, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35386183

RESUMO

Background: Transformation to a lung neuroendocrine tumor (LNET) is a mechanism of resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI). Serum neuron-specific enolase (NSE) is a useful marker in the detection of LNET. Therefore, we explored the clinical significance of serum NSE levels in the detection of transformed neuroendocrine tumors after EGFR-TKI therapy. Methods: We report a cohort of 5 cases in our treatment group. The characteristics of the patients, pathological diagnoses, immunohistochemistry with molecular detection, laboratory examination, and treatment histories are analyzed. The tumor markers of serum NSE were analyzed. Additionally, we reviewed the publications reporting the tumor markers before and after LNET transformation during EGFR-TKI therapy. Results: Most patients are female (3/5), aged <60 years old (4/5), nonsmokers (4/5) and harbor the EGFR 19 exon deletion (4/5). The median time of LNET transformation was 19 months (range: 12-31 months). The clinical characteristics were similar to those reported in previous studies. Laboratory examination revealed an increased NSE level before the LNET is defined. Sixteen publications were reviewed. Of those, 86.67% (13/15) publications showed an increased level of NSE when the LNET transformation was defined. Conclusion: Adenocarcinoma tumors in non-smokers, young patients harboring the EGFR 19 exon deletion tended to transform to LNETs after EGFR-TKI therapy. Combining our findings and a review of the literature, we suggest that serum NSE may be a useful tumor marker to predict neuroendocrine tumor transformation.

5.
PLoS One ; 16(11): e0258907, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34723998

RESUMO

Efficiency and privacy are the key aspects in content extraction signatures. In this study, we proposed a Secure and Efficient and Certificateless Content Extraction Signature with Privacy Protection (SECCESPP) in which scalar multiplication of elliptic curves is used to replace inefficient bilinear pairing of certificateless public key cryptosystem, and the signcryption idea is borrowed to implement privacy protection for signed messages. The correctness of the SECCESPP scheme is demonstrated by the consistency of the message and the accuracy of the equation. The security and privacy of the SECCESPP scheme are demonstrated based on the elliptic curve discrete logarithm problem in the random oracle model and are formally analyzed with the formal analysis tool ProVerif, respectively. Theory and experimental analysis show that the SECCESPP scheme is more efficient than other schemes.


Assuntos
Algoritmos , Segurança Computacional , Privacidade , Modelos Teóricos , Fatores de Tempo
6.
Nanotechnology ; 33(11)2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34844218

RESUMO

Lithium-sulfur (Li-S) batteries with tremendous energy density possess great promise for the next-generation energy storage devices. Even though, the shuttle effect and sluggish redox kinetics of lithium polysulfides (LiPSs) seriously restrict practical applications of Li-S batteries. Herein, a three-dimensionally ordered macro/mesoporous TiN (3DOM TiN) nanostructure is established via using poly (methyl methacrylate) PMMA spheres as template. The interconnected macro/mesoporous channels are constructed to effectively alleviate the stacking of composite materials and render a large portion of inherent active sites exposed on the surface region. Moreover, TiN exhibits high electrical conductivity, which efficiently enhances charge-transfer kinetics and guarantees the favorable electrochemical performance of sulfur cathode. More importantly, the as-prepared 3DOM TiN suppresses the shuttle effect and improves the redox kinetics significantly due to strong affinity toward LiPSs. Attributed to these unique features, the S/3DOM TiN electrode achieves an ultrahigh initial discharge capacity of 1187 mAh g-1at 0.2 C, and stable cycling performance of 552 mAh g-1over 500 cycles at 1 C. Meanwhile, the discharge capacity retention of 701 mAh g-1(3.5 mAh cm-2) can be endowed for the S/3DOM TiN electrode under high sulfur loading of 5 mg cm-2after 100 cycles at 0.1 C. Therefore, the 3DOM TiN nanostructure electrocatalyst provides a promising path for developing practically useable Li-S batteries.

7.
Angew Chem Int Ed Engl ; 60(51): 26622-26629, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34463010

RESUMO

Lithium-sulfur (Li-S) batteries are regarded as a promising next-generation system for advanced energy storage owing to a high theoretical energy density of 2600 Wh kg-1 . However, the practical implementation of Li-S batteries has been thwarted by the detrimental shuttling behavior of polysulfides, and the sluggish kinetics in electrochemical processes. Herein, a novel single atom (SA) catalyst with oversaturated Fe-N5 coordination structure (Fe-N5 -C) is precisely synthesized by an absorption-pyrolysis strategy and introduced as an effective sulfur host material. The experimental characterizations and theoretical calculations reveal synergism between atomically dispersed Fe-N5 active sites and the unique carbon support. The results exhibit that the sulfur composite cathode built on the Fe-N5 -C can not only adsorb polysulfides via chemical interaction, but also boost the redox reaction kinetics, thus mitigating the shuttle effect. Meanwhile, the robust three-dimensional nitrogen doped carbon nanofiber with large surface area, and high porosity enables strong physical confinement and fast electron/ion transfer process. Attributed to such unique features, Li-S batteries with S/Fe-N5 -C composite cathode realize outstanding cyclability and rate capability, as well as high areal capacities under raised sulfur loading, which demonstrates great potential in developing advanced Li-S batteries.

8.
Mol Cell Biochem ; 476(2): 619-631, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33070275

RESUMO

Parkinson's disease (PD) is a disorder characterized by a progressive loss of the dopaminergic neurons in the substantia nigra and a depletion of the neurotransmitter dopamine in the striatum. Our published results indicate that fasciculation and elongation protein zeta-1 (FEZ1) plays a role in the astrocyte-mediated protection of dopamine neurons and regulation of the neuronal microenvironment during the progression of PD. In this study, we examined the effects of engrafted type-2 astrocytes (T2As) with high expression of FEZ1 on the improvement of the symptoms and functional reconstruction of PD rats. T2As were stereotactically transplanted into the striatum of rats with PD induced by 6-hydroxydopamine (6-OHDA). An examination of apomorphine (APO)-induced rotations was performed to evaluate dopamine neuron damage and motor functions. Remarkably, the grafted cells survived in the lesion environment for six weeks or longer after implantation. In addition, the transplantation of T2As decrease the average velocity and the duration time of the APO-induced rotations, and increase the actuation time, as measured in the rotation behavioural tests. In the substantia nigra, the transplantation of T2As reduced the PD-induced GFAP, TH and FEZ1 downregulation. The grafted cells exclusively migrated to other regions near the injection site in the striatum and differentiated into GFAP+ astrocytes or TH+ neurons. Furthermore, by detecting monoamine neurotransmitters through high-performance liquid chromatography, we found that the nigrostriatal pathway had been repaired to some extent. Taken together, these results suggest that engrafted T2As with high expression of FEZ1 improved the symptoms and functional reconstruction of PD rats, providing a theoretical basis for FEZ1 as a potential target and engraftment of T2As as a therapeutic strategy in the treatment of PD.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apomorfina/farmacologia , Astrócitos/transplante , Neurônios Dopaminérgicos/efeitos dos fármacos , Doença de Parkinson/terapia , Substância Negra/metabolismo , Adrenérgicos/administração & dosagem , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Masculino , Atividade Motora/efeitos dos fármacos , Oxidopamina/administração & dosagem , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Ratos , Ratos Sprague-Dawley
9.
Int J Radiat Oncol Biol Phys ; 78(5): 1541-7, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21092834

RESUMO

PURPOSE: To determine the impact of prolonged fraction delivery times (FDTs) simulating intensity-modulated radiotherapy (IMRT) on cultured nasopharyngeal carcinoma (NPC) cell killing. METHODS AND MATERIAL: Cultured NPC cell lines CNE1 and CNE2 were used in this study. The biological effectiveness of fractionated irradiation protocols simulating conventional external beam radiotherapy and IMRT (FDT of 15, 36, and 50 minutes) was estimated with standard colony assay, and the differences in cell surviving fractions after irradiation with different protocols were tested by use of the paired t test. The impact degree of prolonged FDTs (from 8 to 50 minutes) on cell killing was also assessed by the dose-modifying factors, which were estimated by comparing the effectiveness of intermittently delivered 2 Gy with that of continuously delivered 1.5 to 2 Gy. RESULTS: The cell surviving fractions of both CNE1 and CNE2 after fractionated irradiation simulating IMRT were higher than those simulating conventional external beam radiotherapy (p < 0.05). The dose-modifying factors for a fraction dose of 2 Gy increased from 1.05 to 1.18 for CNE1 and from 1.05 to 1.11 for CNE2 with the FDT being prolonged from 15 to 50 minutes. CONCLUSIONS: This study showed that the prolonged FDTs simulating IMRT significantly decreased the cell killing in both CNE1 and CNE2 cell lines, and these negative effects increased with the FDT being prolonged from 15 to 50 minutes. These effects, if confirmed by in vivo and clinical studies, need to be considered in designing IMRT treatments for NPC.


Assuntos
Neoplasias Nasofaríngeas/radioterapia , Radioterapia de Intensidade Modulada/métodos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Fracionamento da Dose de Radiação , Humanos , Neoplasias Nasofaríngeas/patologia , Eficiência Biológica Relativa , Fatores de Tempo , Células Tumorais Cultivadas
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