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1.
Nanoscale ; 15(33): 13740-13749, 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37577851

RESUMEN

Graphitic carbon-based anodes for lithium-ion batteries have seen remarkable development and commercial acceptance during the past three decades. Still, the performance of these materials is limited due to the low surface area, stacking of layers, poor porosity, and meager conductivity. To overcome these limitations, we propose using polystyrene as a core and small-sized zeolitic imidazolate framework-67 (ZIF-67) particles as decorators to develop a highly porous three-dimensional graphitic carbon material. The developed material is optimized with the carbonization temperature for the best anodic performance of LIBs. The pyridinic nitrogen content in the material carbonized at 700 °C makes it high performing and more stable than the samples treated at 600, 800, and 900 °C. The packed coin cell exhibited an initial discharge capacity of 775 mA h g-1 at a current density of 50 mA g-1, which increases to 806 mA h g-1 after testing the material at different current densities for 55 cycles. The packed half-cell exhibited a highly stable performance of about 96% even after testing for 2000 cycles at 1 A g-1.

2.
ACS Appl Mater Interfaces ; 15(20): 24366-24376, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37186545

RESUMEN

Aqueous zinc-ion batteries (ZIBs) provide a safer and cost-effective energy storage solution by utilizing nonflammable water-based electrolytes. Although many research efforts are focused on optimizing zinc anode materials, developing suitable cathode materials is still challenging. In this study, one-dimensional, mixed-phase MnO2 nanorods are synthesized using ionic liquid (IL). Here, the IL acts as a structure-directing agent that modifies MnO2 morphology and introduces mixed phases, as confirmed by morphological, structural, and X-ray photoelectron spectroscopy (XPS) studies. The MnO2 nanorods developed by this method are utilized as a cathode material for ZIB application in the coin-cell configuration. As expected, Zn//MnO2 nanorods show a significant increase in their capacity to 347 Wh kg-1 at 100 mA g-1, which is better than bare MnO2 nanowires (207.1 Wh kg-1) synthesized by the chemical precipitation method. The battery is highly rechargeable and maintains good retention of 86% of the initial capacity and 99% Coulombic efficiency after 800 cycles at 1000 mA g-1. The ex situ XPS, X-ray diffraction, and in-depth electrochemical analysis confirm that MnO6 octahedra experience insertion/extraction of Zn2+ with high reversibility. This study suggests the potential use of MnO2 nanorods to develop high-performance and durable battery electrode materials suitable for large-scale applications.

3.
Toxicol Appl Pharmacol ; 374: 41-52, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31047981

RESUMEN

Arsenic is an environmental toxicant with long-term exposure associated with the development of urothelial carcinomas. Our lab has developed an in-vitro model of urothelial carcinoma by exposing the immortal, but non-tumorigenic bladder cell line, the UROtsa, to arsenite (As3+). These transformed cells form tumors in immune-compromised mice, which resemble urothelial carcinomas with components of the tumor exhibiting squamous differentiation. The goal of the present study was to determine the differences in global gene expression patterns between the As3+-transformed UROtsa cells and the urospheres (spheroids containing putative cancer initiating cells) isolated from these cell lines and to determine if the genes involved in the development of squamous differentiation were enriched in the urospheres. The results obtained in this study show an enrichment of genes such as KRT1, KRT5, KRT6A, KRT6B, KRT6C, KRT14 and KRT16 associated with squamous differentiation, a characteristic feature seen in aggressive basal subtypes of urothelial cell carcinoma (UCC) in the urospheres isolated from As3+-transformed UROtsa cells. In addition, there is increased expression of several of the small proline-rich proteins (SPRR) in the urospheres and overexpression of these genes occur in UCC's displaying squamous differentiation. In conclusion, the cancer initiating cells present in the urospheres are enriched with genes associated with squamous differentiation.


Asunto(s)
Arsenitos/toxicidad , Transformación Celular Neoplásica/inducido químicamente , Células Epiteliales/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias de Células Escamosas/metabolismo , Urotelio/citología , Biomarcadores de Tumor , Línea Celular Tumoral , Análisis por Conglomerados , Epigénesis Genética , Humanos , Análisis por Matrices de Proteínas , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología
4.
J Neurosci Rural Pract ; 3(1): 71-3, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22346199

RESUMEN

Choroid plexus carcinoma is a very rare tumor in adults. Here we report a rare case of choroid plexus carcinoma in an adult patient. A 24-year-old male presented with a right temporal intraventricular tumor with a cystic component also extending up to the cortex. Histological examination revealed complex papillary structures and glandular spaces showing stratification and multilayering of cells with nuclear crowding and numerous mitotic figures and large areas of necrosis. The patient went through a complete search for a possible primary keeping in mind the differential diagnosis of metastatic carcinoma that is more common in adults but there was no evidence of any other tumor. Finally a diagnosis of choroid plexus carcinoma was rendered. Immunohistochemical analysis for p53 protein showed positivity. Choroid plexus carcinoma is exceptionally rare in adults but cases do occur.

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