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1.
PLoS One ; 19(7): e0306093, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39046984

RESUMEN

With the development of e-commerce and the increase of consumers' green consciousness, more and more consumers purchase green products online. The frequent occurrence of the fake green product in online shopping has been harmful to the management and operation of the online market. In order to find the ways for the platform to supervise effectively green products quality problems, we consider the role of blockchain technology, the dynamic penalty mechanisms, the three strategy choices of seller, and the green awareness of consumers, and establish a supervision game model with the participation of online platform, online seller and consumer, which analyzes the equilibrium state of the three parties. The results show that (1) the level of the consumers' green awareness, the compensation for green consumers, and the cost saved by non-green products are the critical factors to ensure the effectiveness of the platform punishment mechanism; (2) the combine effect of dynamic punishment and blockchain supervision can effectively and rapidly improve the quality of green products; (3) the improvement of consumers' green awareness can drive sellers to sell green product, and makes the platform to strengthen the supervision of fake green products.


Asunto(s)
Cadena de Bloques , Comercio , Comportamiento del Consumidor , Humanos , Internet
2.
Sci Rep ; 14(1): 15758, 2024 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-38977800

RESUMEN

The role of SLC3A2, a gene implicated in disulfidptosis, has not been characterized in gliomas. This study aims to clarify the prognostic value of SLC3A2 and its influence on glioma. We evaluated the expression of SLC3A2 and its prognostic importance in gliomas using publicly accessible databases and our clinical glioma samples and with reliance on Meta and Cox regression analysis approaches. Functional enrichment analyses were performed to explore SLC3A2's function. Immune infiltration was evaluated using CIBERSORT, ssGSEA, and single-cell sequencing data. Additionally, Tumor immune dysfunction and exclusion (TIDE) and epithelial-mesenchymal transition scores were determined. CCK8, colony formation, migration, and invasion assays were utilized in vitro, and an orthotopic glioma xenograft model was employed in vivo, to investigate the role of SLC3A2 in gliomas. Bioinformatics analyses indicated high SLC3A2 expression correlates with adverse clinicopathological features and poor patient prognosis. Upregulated SLC3A2 influenced the tumor microenvironment by altering immune cell infiltration, particularly of macrophages, and tumor migration and invasion. SLC3A2 expression positively correlated with immune therapy indicators, including immune checkpoints and TIDE. Elevated SLC3A2 was revealed as an independent risk element for poor glioma prognosis through Cox regression analyses. In vitro experiments showed that reduced SLC3A2 expression decreased cell proliferation, migration, and invasion. In vivo, knockdown of SLC3A2 led to a reduction in tumor volume and prolonged survival in tumor-bearing mice. Therefore, SLC3A2 is a prognostic biomarker and associated with immune infiltration in gliomas.


Asunto(s)
Neoplasias Encefálicas , Regulación Neoplásica de la Expresión Génica , Glioma , Glioma/genética , Glioma/patología , Glioma/metabolismo , Humanos , Pronóstico , Animales , Ratones , Línea Celular Tumoral , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/inmunología , Movimiento Celular , Microambiente Tumoral/inmunología , Proliferación Celular , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Cadena Pesada de la Proteína-1 Reguladora de Fusión/genética , Cadena Pesada de la Proteína-1 Reguladora de Fusión/metabolismo , Femenino , Masculino , Transición Epitelial-Mesenquimal/genética , Ratones Desnudos
3.
J Chromatogr A ; 1696: 463986, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37059047

RESUMEN

The simultaneous quantification of amino acids (AAs) in solid beverages without prior derivatization was explored by high-performance liquid chromatography (HPLC) coupled to a potentiometric detector. Included were threonine, leucine, methionine, phenylalanine, and histidine. The potentiometric detector was made consisting of a copper(II)-selective electrode based on a polyvinyl chloride (PVC) membrane, and the potential changes in the detector were determined according to the coordination interactions between cupric copper ions released from the inner filling solution of the electrode and AAs. Conditions were optimized for effective separation and sensitive detection. Fundamental characteristics such as linearity, limits of detection, limits of quantitation, accuracy, precision, and robustness were validated experimentally. The calibration curves showed a linear relationship between peak heights and the injection concentrations of the AAs. The detection limits down to the sub-micromolar range were achieved under isocratic conditions, outperforming ultraviolet detection. The copper(II)-selective electrode had a minimum lifetime of one month. Some real samples were examined to further demonstrate the feasibility of the proposed approach. The measurement results obtained by the present method were in good agreement with those obtained by the HPLC-mass spectrometry (MS), indicating that the combined HPLC-potentiometric method is a potential option for quantifying AAs.


Asunto(s)
Aminoácidos , Cobre , Cromatografía Líquida de Alta Presión/métodos , Aminoácidos/química , Espectrometría de Masas , Electrodos
4.
Opt Lett ; 37(7): 1268-70, 2012 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-22466217

RESUMEN

Important for telecommunications, luminescence of trivalent erbium (Er) at 1.5 µm generally arises from a Stokes-shifted downconversion mechanism. We show that this luminescence following direct excitation of the 4I11/2 state is generated by upconversion-mediated looping process in Er3+/Sc3+-codoped LiNbO3 single crystal. Emissions at 1.0 and 1.5 µm from the 4I11/2 and 4I13/2 states display linear and quadratic dependences on the excitation density in two separated ranges with a threshold of 20 W/cm2. This observation correlates with two- and four-photon processes in green and red upconversion emissions. The mechanism described has implications in the improvement of the output of 1.5 µm luminescence.


Asunto(s)
Erbio/química , Luminiscencia , Niobio/química , Óxidos/química , Escandio/química , Láseres de Semiconductores , Espectrometría de Fluorescencia
5.
Opt Lett ; 36(7): 1056-8, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21478981

RESUMEN

Based on repetition frequency-dependent excited state absorption (ESA) upconversion (UC) luminescence, a method to measure the lifetime of an IR intermediate level is proposed so long as ESA UC luminescence can occur in the rare earth ions. The feasibility of this idea is demonstrated via a theoretical simulation. A Er(3+):LiNbO3 crystal ESA UC luminescence under femtosecond laser excitation is used to illustrate this measurement method, and the obtained 1.5 µm lifetime of 2.31 ms is shorter than previous reported values. This method can obviate the influence of radiation trapping effect on lifetime measurement, which is crucial in the traditional pulse sampling technique.


Asunto(s)
Rayos Infrarrojos , Mediciones Luminiscentes/métodos , Absorción , Láseres de Estado Sólido , Factores de Tiempo
6.
RSC Adv ; 8(10): 5145-5150, 2018 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-35542425

RESUMEN

A series of Sc:Ru:Fe:LiNbO3 crystals with various levels of Sc2O3(0, 1, 2, and 3 mol%) doping were grown from congruent melts in air by using the Czochralski technique. The defect structures and photorefractive properties of the Sc:Ru:Fe:LiNbO3 crystals were investigated by acquiring infrared spectra of the crystals and performing two-wavelength nonvolatile experiments, respectively. Our results showed the holographic storage properties of Ru:Fe:LiNbO3 crystals to be enhanced by doping them with a high concentration of Sc2O3, and indicated Sc:Ru:Fe:LiNbO3 crystals to constitute a promising medium for holographic storage.

7.
Appl Opt ; 44(21): 4569-73, 2005 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-16047908

RESUMEN

The threshold concentration for In2O3 was found in In:Mn:Fe:LiNbO3 crystals by measurement of the infrared spectra of the crystals. The resistance of the In:Mn:Fe:LiNbO3 crystals to optical damage is characterized by changes in photoinduced birefringence as well as by distortion of the transmitted beam pattern. The resistance increases remarkably when the concentration of In2O3 exceeds its threshold. The resistance to optical damage of a In(3.0 mol. %):Mn:Fe:LiNbO3 crystal is 2 orders of magnitude higher that of a Mn:Fe:LiNbO3 crystal. The dependence of defects on the resistance to optical damage of the In:Mn:Fe:LiNbO3 crystals is discussed in detail. Nonvolatile holographic storage was achieved for all crystals, and the sensitivity of the In(3.0 mol. %):Mn:Fe:LiNbO3 crystal is much higher than that of the others.

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