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1.
Appl Opt ; 63(12): 3174-3177, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38856463

RESUMEN

This study reports on a composite structure composing tilted taper, and tilted and curved waveguides with the aim of enhancing the spectral width and output power of mid-infrared quantum cascade superluminescent emitters (QC-SLEs). The computational results indicate that a tilt angle of 10° and a curved angle of 20° can avoid the selectivity of a certain wavelength due to interference effects at tilt angles of 6° and 8°, resulting in the minimum reflectivity of 1.3×10-4 and 4.4×10-4 for each wide and narrow cavity surface. Simultaneously, the modes propagating perpendicular to the cavity surface exist the least. The corresponding experimental results show a significant enhancement in the spectral width to 168.5c m -1 and a high power output of 5.1 mW for the device. This study presents what we believe to be a novel concept for the designing of superluminescent emitters with both a broadband and high power output.

2.
Entropy (Basel) ; 25(10)2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37895503

RESUMEN

In severe low-visibility environments full of smoke, because of the performance degeneration of the near-infrared (NIR) collimation system of quantum drones communication networks, the improved dual-threshold method based on trend line analysis for long-wave infrared (LWIR) quantum cascade lasers (QCLs) is proposed, to achieve target acquisition. The simulation results show that smoke-scattering noise is a steeply varying medium-high-frequency modulation. At particle sizes less than 4 µm, the traditional dual-threshold method can effectively distinguish the target information from the smoke noise, which is the advantage of the LWIR laser compared to the NIR laser. For detecting lasers with high signal-to-noise ratios (SNRs), the method can achieve good target acquisition, by setting reasonable conventional thresholds, such as 0.7 times the peak intensity and 0.8 times the peak rising velocity. At low SNRs and steep intensity variation, the method can also achieve good target acquisition, by adaptively resetting new thresholds after filtering the detecting laser, such as 0.6 times the peak intensity and 0.6 times the peak rising velocity. The results of this paper will provide a reference for the performance improvement and refinement of the collimation system for wireless quantum communication networks in low visibility.

3.
Appl Opt ; 62(5): 1364-1368, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36821240

RESUMEN

Distributed feedback quantum cascade lasers lased at 3.0 THz were prepared and their output performance was analyzed. The optimized grating parameters were obtained by theoretical analyses. Single-mode emission was obtained and a maximum output power of more than 166 mW at 15 K was achieved. The corresponding threshold current density was 257A/c m 2, and the side-mode suppression ratio was more than 15 dB. By changing the input voltage, the frequency was stable with a variation of less than 3 GHz. A beam with obviously fast and slow axis features was observed. Further improvement and the potential application of distributed feedback quantum cascade lasers are discussed.

4.
Front Oncol ; 12: 1085305, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36561518

RESUMEN

Background: To explore the changes and significance of the expression level and nutritional status of human insulin-like growth factor binding protein-2 (IGFBP2) after the treatment of esophageal cancer with left neck anastomosis combined with placement of feeding nutritional applicators carrying ^(125)I particles. Methods: A total of 110 patients with esophageal cancer (observation group: left neck anastomosis combined with placement of feeding nutritional applicators carrying ^(125)I particles) and 100 healthy people (control group) were enrolled at the same period. Then enzyme-linked immunosorbent assay (ELISA) was carried out to detect level of IGFBP-2. Lymphocyte count and serum albumin were measured by immune analyzer and automatic protein analyzer to evaluate nutritional status. Logistic regression analysis was used to analyze the relationship between serum IGFBP-2, nutritional status and prognosis of esophageal cancer after combined treatment. Results: The albumin, lymphocyte absolute value and PNI detection value of the control group were lower than those of the observation group 1 month after treatment, and the difference was statistically significant compared with the control group. The detection value of IGFBP-2 in early patients before and after treatment was lower than that in middle and late patients, and the detection values of albumin, lymphocyte absolute value and PNI were higher than those in middle and late patients, the differences were statistically significant. Serum IGFBP-2 level was negatively correlated with PNI, and albumin and lymphocyte absolute value were positively correlated with PNI. The detection value of IGFBP-2 in patients with good prognosis was significantly lower than that in patients with poor prognosis, and the detection values of albumin, lymphocyte absolute value and PNI were significantly higher than those in patients with poor prognosis. The AUC (0.887,95% CI: 0.799-0.975) of IGFBP-2, albumin, lymphocyte absolute value and PNI in predicting poor prognosis of esophageal cancer was the largest, and the sensitivity and specificity were 94.12% and 92.47%, respectively. Conclusions: Left neck anastomosis combined with ^(125)I particle application nutritional tube is helpful for the decrease of serum IGFBP-2 and the increase of various nutritional status indicators, which is beneficial for the improvement of the patient's condition.

5.
Polymers (Basel) ; 14(21)2022 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-36365598

RESUMEN

The exploding foil initiator (EFI) system has been extensively used in ignition and detonation sequences and proved to be of high safety and reliability. Polyimide is considered the ideal flyer material for EFI due to its excellent performance, including thermal stability, outstanding mechanical properties, high radiation resistance, and excellent dielectric properties. In this study, we prepared the EFI based on a polyimide (ODPA-ODA) flyer, which is spin-coated and solidified on patterned copper film in situ. The electric explosion test shows that the prepared EFI has good working performance, and the 4000 V working voltage drove the flyer to reach a maximum velocity of 5096 m/s. The polyimide morphology and chemical structure after the electric explosion was observed by microscope, SEM, XPS, and FTIR, which showed that the polyimide flyer underwent thermal deformation and complex chemical reactions during an electric explosion. A large number of polyimide bonds broke to form new carbonyl compounds, and the opening of aromatic rings was accompanied by the formation of aliphatic hydrocarbon chains. The morphology and chemical structure analysis after the electric explosion test will lay a foundation for us to further understand the working principle and evolution process of polyimide (ODPA-ODA) flyer.

6.
J Biosci ; 472022.
Artículo en Inglés | MEDLINE | ID: mdl-36222132

RESUMEN

Non-small-cell lung cancer (NSCLC) is the most prevalent type of lung cancer. This study evaluated the mechanism of histone methyltransferase SET and MYND domain-containing 3 (SMYD3) in the abnormal proliferation of NSCLC cells. The human bronchial epithelial cell (HBEC) line (16HBE) and NSCLC cell lines (H1299, A549, H460, and H1650) were collected. A549 and H1650 cells were transfected with si-SMYD3 and Anoctamin-1 (ANO1) and their negative controls or treated with BCI-121, or A549 cells were treated with CPI-455. SMYD3, H3 lysine 4 tri-methylation (H3K4me3), and ANO1 levels in the cells were detected. The proliferation ability of A549 and H1650 cells were examined. We found that SMYD3, H3K4me3, and ANO1 were highly expressed in NSCLC cell lines. Silencing SMYD3 or SMYD3 activity in A549 and H1650 cells inhibited the cell proliferation ability and decreased H3K4me3 level and ANO1 mRNA level in the cells. H3K4me3 upregulation orANO1 overexpression reversed the inhibitory effects of silencing SMYD3 on the abnormal proliferation of NSCLC cells. Chromatin-Immunoprecipitation (Ch-IP) assay detected that SMYD3 bound to and enriched in the ANO1 promoter region, and the ANO1 promoter region was enriched with H3K4me3. Collectively, SMYD3 promoted ANO1 transcription by upregulating H3K4me3 in the ANO1 promoter region, thus facilitating the abnormal proliferation of NSCLC cells.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Anoctamina-1/genética , Anoctamina-1/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/genética , Línea Celular Tumoral , Proliferación Celular/genética , Cromatina , Regulación Neoplásica de la Expresión Génica , N-Metiltransferasa de Histona-Lisina/genética , Histonas , Humanos , Neoplasias Pulmonares/genética , Lisina/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , ARN Mensajero/genética
7.
Nanomaterials (Basel) ; 12(15)2022 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-35893497

RESUMEN

High-power, incoherent THz array sources are widely desired in some applications due to their low energy, unique terahertz fingerprint, and image. In this work, a dual ridge terahertz quantum cascade laser lasing at 3.1 THz is presented, and the device's performance is analyzed in detail. The maximum output power can reach 512 mW when the two ridges work simultaneously in continuous-wave mode, with a threshold current density of 281 A/cm2 at 15 K. While the peak power is approximately 704 mW in pulse-wave mode at 15 K, the lasing still could be observed approximately 7 mW at 125 K. The far-field pattern of the dual ridge THz QCL is detected by a THz camera; two light spots typically show a single-lobe Gaussian distribution. The experimental results provide a reference for realizing high-power THz quantum cascade lasers, and they will provide some guidance for the structural design of multiple ridges or laser arrays.

8.
J Oncol ; 2021: 4451533, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34824582

RESUMEN

BACKGROUND: Carnosic acid (CA) is a polyphenolic diterpene extracted from rosemary. Reports have shown that CA possesses anticancer activity. However, whether CA inhibits esophageal squamous cell carcinoma, an aggressive type of esophageal cancer, remains untested. METHODS: The effects of CA on cell survival, migration, and apoptosis were evaluated by a combination of MTT, colony formation assay, flow cytometry, and Transwell assay. The potential signaling pathways involved were investigated via Western blot assay. RESULTS: CA dose-dependently inhibited cell proliferation, apoptosis, migration, and colony formation. Mechanistically, CA arrested the cell cycle at G2/M phase, promoted cell apoptosis, induced DNA damage, and inhibited the MAPK signaling pathways. CONCLUSION: Our results suggest that CA is a potential anticancer drug for esophageal squamous cell carcinoma.

9.
J BUON ; 26(4): 1453-1459, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34565004

RESUMEN

PURPOSE: To investigate the short- and medium-term outcomes following treatment with uniportal video-assisted thoracic surgery lobectomy (uniportal VATS) in elderly patients with non-small cell lung cancer (NSCLC). METHODS: We conducted a retrospective analysis on the clinical and follow-up data of 74 elderly patients with NSCLC who underwent uniportal VATS between January 2015 and January 2020. One-to-one propensity score matching (PSM) was employed to select 71 elderly patients with NSCLC who underwent multiportal video-assisted thoracoscopic lobectomy (multiportal VATS) during the same period. RESULTS: The baseline characteristics of the two patient groups were comparable, with no statistically significant differences in postoperative complications, operation time, conversion to thoracotomy, or lymph node dissection. The amount of intraoperative blood loss and postoperative pain were lower in the uniportal VATS group than in the multiportal VATS group. The 3-year overall survival and disease-free survival of the two groups were similar. CONCLUSIONS: Uniportal VATS achieved similar short- and medium-term outcomes as Multiportal VATS in elderly patients with NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/cirugía , Neoplasias Pulmonares/cirugía , Neumonectomía/métodos , Cirugía Torácica Asistida por Video/métodos , Factores de Edad , Anciano , Femenino , Humanos , Masculino , Estudios Retrospectivos , Cirugía Torácica Asistida por Video/instrumentación , Factores de Tiempo , Resultado del Tratamiento
10.
Clin Lab ; 67(4)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33865247

RESUMEN

BACKGROUND: Red blood cell distribution width (RDW) is a parameter reported in blood routine examination, and has been reported as an inflammatory biomarker. The objective of this study was to investigate the significance of RDW in NSCLC patients with EGFR mutations. METHODS: The clinical data of 102 patients with NSCLC who underwent radical resection surgery in the First Affiliated Hospital of Wenzhou Medical University from December 2012 to November 2017 were collected. Kaplan-Meier survival analysis and Cox proportional hazard models were used to examine the effect of RDW on survival. RESULTS: The RDW levels were divided into two groups: high RDW (≥ 13.1%), n = 47 vs. low RDW, n = 55 (< 13.1%). Univariate analysis showed that there were significant associations of high RDW values with smoking history and brain metastasis. Forty-seven patients with elevated RDW levels had shorter progression-free survival (PFS) than 55 patients with normal RDW levels (264 vs. 310 days, p = 0.039). CONCLUSIONS: RDW is associated with several factors that reflect inflammation and malnutrition in lung cancer patients. Moreover, high levels of RDW are associated with poor survival.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Índices de Eritrocitos , Humanos , Pronóstico , Estudios Retrospectivos
11.
Materials (Basel) ; 12(16)2019 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-31394784

RESUMEN

Based on the requirements of underwater acoustic stealth, the classification and research background of acoustic coatings are introduced herein. The research significance of acoustic coatings is expounded from the perspective of both the military and civilian use. A brief overview of the conventional design process of acoustic coatings is presented, which describes the substrates used in different countries. Aimed at the local design of acoustic coatings, research progress on passive and semi-active/active sound absorption structure is summarized. Focused on the passive acoustic coatings; acoustic cavity design and optimization, acoustic performance of acoustic coatings with rigid inclusions or scatterers, and acoustic coatings with a hybrid structure are discussed. Moreover, an overview of the overall design of acoustic coatings based on the sound field characteristics of the submarine is also presented. Finally, the shortcomings of the research are discussed, breakthroughs in acoustic coating design research are forecast, and the key technical issues to be solved are highlighted.

12.
Appl Opt ; 55(3): A43-8, 2016 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-26835956

RESUMEN

Terahertz digital holography is a combination of terahertz technology and digital holography. In digital holography, the imaging resolution is the key parameter in determining the detailed quality of a reconstructed wavefront. In this paper, the synthetic aperture method is used in terahertz digital holography and the in-line arrangement is built to perform the detection. The resolved capability of previous terahertz digital holographic systems restricts this technique to meet the requirement of practical detection. In contrast, the experimental resolved power of the present method can reach 125 µm, which is the best resolution of terahertz digital holography to date. Furthermore, the basic detection of a biological specimen is conducted to show the practical application. In all, the results of the proposed method demonstrate the enhancement of experimental imaging resolution and that the amplitude and phase distributions of the fine structure of samples can be reconstructed by using terahertz digital holography.

13.
Nanoscale ; 8(8): 4628-34, 2016 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-26853784

RESUMEN

Conventionally, electrical transport of quantum subbands occurs at very high electric fields, indicating that the medium is easy to break down. In the experiments and practical applications, the extreme condition is difficult to satisfy. For quantum information transmission, low power consumption and convenient implementation are what we expect. In this paper, we engineered a special quantum dot array (QDA) embedded in a single crystal matrix. By external optical field excitation, we found a series of subbands made of the self-assembled QDA discretely located in the matrix. Changing the spacing between the quantum dots leads to the variation of subband spacing. Artificially manipulating the microcosmic QDA system can bring interesting macroscopic effects, such as an enhanced absorption intensity in the ultraviolet range, a blue-shift of the surface plasmon resonance peak and nonlinear absorption changed from two-photon absorption to saturated absorption. The intrinsic mechanism of the subband optical response was revealed due to the strong quantum confinement effect and dominant intraband transitions. The weak surface plasmon resonance absorption of Ni QDA gave an excellent figure of merit of the order of 10(-10). The composite films are expectation enough to become a prime candidate for nonlinear applications near 532 nm. Therefore with interplay of the weak optical field and subbands, we achieved a tunable photoelectron transport process.

14.
Nanoscale ; 6(22): 13876-81, 2014 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-25307500

RESUMEN

A self-assembled quantum dots array (QDA) is a low dimensional electron system applied to various quantum devices. This QDA, if embedded in a single crystal matrix, could be advantageous for quantum information science and technology. However, the quantum tunneling effect has been difficult to observe around room temperature thus far, because it occurs in a microcosmic and low temperature condition. Herein, we show a designed a quasi-periodic Ni QDA embedded in a single crystal BaTiO3 matrix and demonstrate novel quantum resonant tunneling transport properties around room-temperature according to theoretical calculation and experiments. The quantum tunneling process could be effectively modulated by changing the Ni QDA concentration. The major reason was that an applied weak electric field (∼10(2) V cm(-1)) could be enhanced by three orders of magnitude (∼10(5) V cm(-1)) between the Ni QDA because of the higher permittivity of BaTiO3 and the 'hot spots' of the Ni QDA. Compared with the pure BaTiO3 films, the samples with embedded Ni QDA displayed a stepped conductivity and temperature (σ-T curves) construction.

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