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1.
Sensors (Basel) ; 24(3)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38339558

RESUMO

The circular waveguide aperture or open-end radiator, one of the canonical antenna elements, can be filled with a dielectric material for miniaturization. With dielectric filling, the aperture reflection increases and impedance matching is necessary. This paper presents a simple but innovative simulation-based approach to the aperture matching of a dielectric-filled circular waveguide aperture. By properly loading the aperture with two- or three-section dielectric rings, the impedance matching is possible over a wide frequency range starting slightly above the TE11-mode cutoff and continuing upward. The material for the aperture matching is the same as that filling the waveguide. The proposed matching structure is analyzed and optimized using a simulation tool for the dielectric constant εr of the filling material ranging from 1.8 to 10. For εr ≥ 5, the unmatched reflection coefficient ranges from -6.0 dB to -0.9 dB while the matched reflection coefficient is from -20.4 dB to -10.0 dB. The impedance matching has been achieved over more than an octave bandwidth.

2.
Sensors (Basel) ; 23(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38005561

RESUMO

The maximum reflection at an open end of a standard rectangular waveguide is about -10 dB in its operating frequency range. It is often used without matching. For critical applications, it is desirable to further reduce the reflection coefficient. In this paper, a new technique is presented for the broadband impedance matching of an open-ended rectangular waveguide. The proposed technique employs three thin capacitive matching elements placed at proper intervals via a low-loss dielectric material. The capacitance of, and distance between, the matching elements are optimized for broadband impedance matching using a simulation tool. Based on the proposed technique, two design examples are presented for the matching of a WR75 waveguide radiator. A reflection coefficient of less than -16 dB and -20 dB has been achieved over a ratio bandwidth of 2.13:1 and 1.62:1, respectively.

3.
J Pharm Pharmacol ; 74(9): 1251-1260, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35789274

RESUMO

OBJECTIVES: Cervical cancer (CC) is the common female malignant tumour with non-negligible morbidity and mortality. Eleutheroside E (EE) has anti-oxidative stress, anti-inflammatory and anti-proliferation effects in diverse disease models. However, its anti-tumour role remains unclear. METHODS: The cell viability, apoptosis rate and protein expressions were detected by CCK-8, flow cytometry and western blot assays, respectively. The metabolic profile was performed by GC/MS analysis. Furthermore, the effect of EE on CC was verified in nude mice. KEY FINDINGS: EE notably decreased the viability and increased the cell apoptosis, which could be reversed with 740Y-P treatment. EE treatment changed the metabolic categories of SiHa cells. The fatty acids signalling pathway was the most outstanding differential pathway. Myo-inositol prominently enhanced the level of phosphorylated Akt in a dose-dependent way. Moreover, EE declined the tumour volume and weight and the proliferation, but promoted the apoptosis in vivo. EE reduced the relative expression of phosphorylated PI3K and Akt. However, all these in-vivo results were observably antagonized with myo-inositol treatment. CONCLUSIONS: EE plays an anti-tumour role in CC via inhibiting the PI3K pathway and reprogramming the metabolic responses.


Assuntos
Antineoplásicos , Neoplasias do Colo do Útero , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Glucosídeos , Humanos , Inositol , Lignanas , Camundongos , Camundongos Nus , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia
4.
Neoplasma ; 69(6): 1406-1417, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36591804

RESUMO

LncRNA carbonyl reductase antisense RNA 1 (CBR3-AS1) is increased in cervical cancer and predicts poor prognosis. This study aims to investigate the underlying mechanism of lncRNA CBR3-AS1 in cervical cancer. LncRNA CBR3-AS1 and LASP1 expressions were significantly elevated in cervical cancer tissue and cells, whereas miR-3163 expression was significantly decreased in cervical cancer tissue and cells. High lncRNA CBR3-AS1 expression and LASP1 expression showed a lower overall survival rate, whereas high miR-3163 expression showed a higher overall survival rate. Correlation between clinicopathological parameters of cervical cancer patients and lncRNA CBR3-AS1, miR-3163, LASP1 expressions indicated that the expressions of lncRNA CBR3-AS1, miR-3163, and LASP1 were closely related with distant metastasis and lymphatic metastasis of cervical cancer. LncRNA CBR3-AS1 knockdown suppressed cervical cancer cell viability and inhibited cancer stem cell-like properties. Besides, we identified that lncRNA CBR3-AS1 interacted with miR-3163, and miR-3163 targeted to LASP1. Moreover, the correlation between lncRNA CBR3-AS1 and miR-3163, as well as the correlation between miR-3163 and LASP1 was confirmed. Finally, lncRNA CBR3-AS1 knockdown inhibited tumor growth and suppressed cancer stem cell-like properties of cervical cancer in vivo. Taken together, high expression of lncRNA CBR3-AS1 predicts poor prognosis in cervical cancer, and the lncRNA CBR3-AS1/miR-3163/LASP1 pathway plays a vital function in the modulation of cervical cancer cell proliferation and cancer stem cell-like properties.


Assuntos
MicroRNAs , RNA Longo não Codificante , Neoplasias do Colo do Útero , Feminino , Humanos , Proteínas Adaptadoras de Transdução de Sinal/genética , Oxirredutases do Álcool/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Proteínas do Citoesqueleto/genética , Regulação Neoplásica da Expressão Gênica , Proteínas com Domínio LIM/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Prognóstico , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
5.
Acta Inform Med ; 27(5): 318-3326, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32210499

RESUMO

INTRODUCTION: The American College of Obstetricians and Gynecologists (ACOG) defines postpartum hemorrhage (PPH) as a blood loss of >500mL following vaginal delivery or >1000mL following cesarean section. PPH is widely recognized as a common cause of maternal death. However, there is currently no effective method to predict its risk of occurrence. AIM: To develop a fuzzy expert system to predict the risk of developing PPH and to evaluate its performance in the clinical setting. METHODS: This system was developed using MATLAB software. Mamdani inference was used to simulate reasoning of experts in the field. To evaluate the performance of the system, a dataset of 1705 patients admitted at the Labor and Delivery ward of The Second Affiliated Hospital of Nanjing Medical University from 2017-10 to 2018-04, was considered. RESULTS: The Negative Predictive value (NPV), Positive Predictive value PPV), Specificity and Sensitivity were calculated and were 99.72%, 18.50%, 87.48% and 92.16% respectively. CONCLUSIONS: Our findings suggest that the fuzzy expert system can be used to predict PPH in clinical settings and thus decrease maternal mortality rate due to hemorrhage.

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