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1.
Materials (Basel) ; 15(8)2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35454596

RESUMEN

The open-layered structure of Vanadium pentoxide (V2O5) has triggered significant interest in exploring its energy-related application as lithium (Li) intercalation cathode material. Various methods are extensively studied to improve the Li diffusion using thin films or nanoarchitecture. In this work, high-quality two-dimensional (2D) inverse opal α-V2O5 films were synthesized via a modified 'dynamic hard template' infiltration strategy using sacrificial polystyrene spheres (PS, a diameter of 530 nm) photonic crystal as a template. The new material exhibited an excellent porous array with featured structural colors in a large area. The electrochromic behavior was explored by combining bandgap and electrochemical characterization. On the one hand, the intercalation/deintercalation of Li+ played an important role in the bandgap (Eg), and thereafter on the visible range transmittance through changing the film's stoichiometry and the valence of vanadium ions. On the other hand, the asymmetry of the lattice due to the disordered distribution of Li+ within the V2O5 interlayer and/or the formation of an irreversible phase explained the change in transmittance with voltage.

2.
Appl Opt ; 60(31): 9781-9789, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34807165

RESUMEN

An ultrawide bandwidth and single-mode polarization beam splitter (PBS) based on an air-gap type of dual-hollow-core antiresonant fiber (DHC-ARF) is proposed. Nested tubes are introduced into two cladding tubes between two cores to weaken the wavelength dependence of coupling length in DHC-ARF for obtaining ultrawide bandwidth. By tuning the cladding tube sizes, higher-order core modes with the lowest loss can be coupled with cladding tube modes, and thus, effectively, single-mode operation is achieved. Numerical results demonstrate that an 8.15 cm long DHC-ARF can be used to develop a PBS with an operating bandwidth of 370 nm ranging from 1.28 to 1.65 µm, where a polarization extinction ratio is below -20dB and a high-order mode extinction ratio exceeds 100.

3.
J Int Med Res ; 49(7): 3000605211029461, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34325571

RESUMEN

OBJECTIVE: To investigate the effects and potential mechanism of action of shikonin (SHK) on the development of ovarian follicles and female germline stem cells (FGSCs). METHODS: Female Kunming adult mice were administered SHK (0, 20 and 50 mg/kg) by oral gavage. Cultures of FGSCs were treated with SHK 32 µmol/l for 24 h. The ovarian index in mouse ovaries was calculated. Numbers of primordial, primary and atretic follicles were counted. Germline stem cell markers and apoptosis were examined. Levels of glutathione (GSH), superoxide dismutase (SOD) and reactive oxygen species (ROS) were measured. RESULTS: Both doses of SHK significantly decreased the ovarian index, the numbers of primordial follicles, primary follicles and antral follicles in mice. SHK significantly increased the numbers of atretic follicles and atretic corpora lutea. SHK promoted apoptosis in vivo and in vitro. SHK significantly decreased the levels of the germline stem cell markers. SHK significantly lowered GSH levels and the activity of SOD in the peripheral blood from mice, whereas SHK significantly elevated cellular ROS content in FGSCs. CONCLUSIONS: These current results suggested that follicular development and FGSCs were suppressed by SHK through the induction of apoptosis and oxidative stress might be involved in this pathological process.


Asunto(s)
Naftoquinonas , Células Madre Oogoniales , Animales , Apoptosis , Femenino , Ratones , Folículo Ovárico
4.
Opt Lett ; 46(8): 1908-1911, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33857101

RESUMEN

We investigate the feasibility of applying an anti-resonant guiding mechanism in an all-solid anti-resonant fiber (AS-ARF) to achieve a large mode area (LMA) and single mode for high-power fiber laser applications. A novel, to the best of our knowledge, AS-ARF with nonuniform rods is proposed to enhance the single-mode property and enlarge the mode area. The numerical results show that the core diameter can expand to 57, 80, and 100 µm at the wavelengths of 1.064, 1.55, and 2 µm, respectively. The loss ratio of the lowest loss of higher-order modes to the loss of the fundamental mode can exceed 1000, 550, and 860 at the wavelength of 1.064, 1.55, and 2 µm; thus, robust single-mode operation can be ensured. Besides, the fiber can also be adapted to bent condition under certain heat load. These indicate that the proposed AS-ARF with nonuniform rods is a great candidate as an LMA fiber for high-power fiber lasers.

5.
Appl Opt ; 59(25): 7621-7629, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32902462

RESUMEN

A novel bend-resistant large mode area fiber with pixeled structure and leakage channel is proposed for application with a tight bend radius at the 2 µm wavelength region. Two layers of discontinuous fluorine-doped silica rods, which are called pixels, are introduced in the cladding. By removing four pixels, the loss of high-order modes is enhanced significantly due to the leakage channel. Bend properties of the fiber are investigated thoroughly by numerical simulations. As a result, a robust single-mode operation is obtained with an ultrahigh loss ratio (the minimum loss of high-order modes to the loss of fundamental mode) exceeding 3×105 when the fiber is bent with a tight radius as 10 cm. The effective mode area can reach 1764µm2. In addition, the fiber can keep high performance within a broad waveband from 1.75 to 2.15 µm. Large mode area and robust single-mode operation with a tight bend radius make this fiber beneficial to the development of 2 µm miniaturized fiber lasers.

6.
Am J Reprod Immunol ; 84(2): e13265, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32395847

RESUMEN

Chronic low-grade inflammation is one cause of follicle development disturbance. Chronic inflammation exists in pathological conditions such as premature ovarian failure, physiological aging of the ovaries, and polycystic ovary syndrome. Inflammation of the whole body can affect oocytes via the follicle microenvironment, oxidative stress, and GM-CSF. Many substances without toxic side-effects extracted from natural organisms have gradually gained researchers' attention. Recently, chitosan oligosaccharide, resveratrol, anthocyanin, and melatonin have been found to contribute to an improvement in inflammation. This review discusses the interrelationships between chronic low-grade inflammation and follicle development, the underlying mechanisms, and methods that may improve follicle development by controlling the level of chronic low-grade inflammation.


Asunto(s)
Oocitos/fisiología , Folículo Ovárico/fisiología , Síndrome del Ovario Poliquístico/inmunología , Insuficiencia Ovárica Primaria/inmunología , Animales , Microambiente Celular , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Humanos , Inmunomodulación , Inflamación , Estrés Oxidativo
7.
Sheng Li Xue Bao ; 71(3): 405-414, 2019 Jun 25.
Artículo en Chino | MEDLINE | ID: mdl-31218331

RESUMEN

The present study was aimed to investigate the expression relationship of Hippo signaling molecules and ovarian germline stem cell (OGSC) markers in the development schedule of OGSCs during ovarian aging in women and mice. The ovaries of 2-month-old mature (normal control) and 12-month-old (physiological ovarian aging) KM mice were sampled, and the ovarian cortex samples of young (postpuberty to 35 years old), middle age (36-50 years old) and menopausal period (51-60 years old) women were obtained with consent. The mice model of pathological ovarian aging was established by intraperitoneal injection of cyclophosphamide/busulfan (CY/BUS). HE staining was used to detect the changes of follicles at different stages, and the localization and expression changes of Hippo signaling molecules and OGSCs related factors (MVH/OCT4) were detected by immunohistochemistry and immunofluorescence staining. Western blot was used to detect the protein expression levels of the major molecules in the Hippo signaling pathway and OGSCs related factors. The results showed that there were not any normal follicles, but a few atresia follicles in the ovaries from physiological and pathological ovarian aging mice. Compared with the normal control mice, both the physiological and pathological ovarian aging mice showed decreased protein expression levels of the main Hippo signaling molecules (pYAP1) and MVH/OCT4; Whereas only the pathological ovarian aging mice showed increased ratio of pYAP1/YAP1. In comparison with the young women, the middle age and menopausal women showed looser structure of ovarian surface epithelium (OSE) and less ovarian cortical cells. The protein expression level of LATS2 in the OSE was the highest in young women, MST1 expression was the lowest in the menopausal period women, and the expression levels of YAP1 and pYAP1 were the highest in middle age women. Compared with the young women, the middle age and menopausal period women exhibited significantly decreased ratio of OSE pYAP1/YAP1, whereas there was no significant difference between them. The expression level of MVH protein in OSE from the young women was significantly higher than those of the middle age and menopausal period women. These results indicate that there is an expression relationship between the main molecules of Hippo signaling pathway and OGSCs related factors, which suggests that Hippo signaling pathway may regulate the expression levels of OGSCs related factors, thus participating in the process of physiological and pathological degeneration of ovarian.


Asunto(s)
Envejecimiento , Células Madre Oogoniales/metabolismo , Ovario , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adulto , Animales , Epitelio , Femenino , Vía de Señalización Hippo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Ratones , Persona de Mediana Edad , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Folículo Ovárico , Fosfoproteínas/metabolismo , Transducción de Señal , Factores de Transcripción , Proteínas Supresoras de Tumor/metabolismo , Proteínas Señalizadoras YAP
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