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1.
Heliyon ; 9(8): e18779, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37664731

ABSTRACT

Objective: Breast cancer is one of the most prevalent cancers in females worldwide and is one of the leading causes of cancer death and disability in women. Multiple therapies have been applied to breast cancer treatment; however, the long-term survival rate remains low. Although cisplatin has been widely utilized for cancer therapy, chemoresistance still influences the outcome. Methods: After collecting the breast cancer cell line MDA-MB-231 treated with or without cisplatin and sample information from The Cancer Genome Atlas Program (TCGA), we screened out their common parameters and influences on the prognoses of patients' potential targets. Surgical excisional tissue sections of patients with breast cancer who were admitted and treated in the Department of Breast and Thyroid Surgery, Liuzhou People's Hospital from 2017 to 2020 was collected and follow up. After a series of assays combined with clinical information, we tested the reliability of the target. Results: We found that a high expression level of ZNF268 in breast cancer cell lines significantly enhances the sensitivity to cisplatin, contrary to the effects of low expression. Furthermore, a significantly worse prognosis was observed in patients with a high expression of ZNF268 after cisplatin chemotherapy. Conclusion: The expression level of ZNF268 in breast cancer patients after cisplatin chemotherapy may become a potential target to predict the chemoresistance of patients to cisplatin. This study provides a novel idea for improving breast cancer treatment and survival rates.

2.
Opt Express ; 30(25): 45612-45623, 2022 Dec 05.
Article in English | MEDLINE | ID: mdl-36522964

ABSTRACT

Metasurface provides an unprecedented means to manipulate electromagnetic waves within a two-dimensional planar structure. Traditionally, the design of meta-atom follows the pattern-to-phase paradigm, which requires a time-consuming brute-forcing process. In this work, we present a fast inverse meta-atom design method for the phase-to-pattern mapping by combining the deep neural network (DNN) and genetic algorithm (GA). The trained classification DNN with an accuracy of 92% controls the population generated by the GA within an arbitrary preset small phase range, which could greatly enhance the optimization efficiency with less iterations and a higher accuracy. As proof-of-concept demonstrations, two reflective functional metasurfaces including an orbital angular momentum generator and a metalens have been numerically investigated. The simulated results agree very well with the design goals. In addition, the metalens is also experimentally validated. The proposed method could pave a new avenue for the fast design of the meta-atoms and functional meta-devices.

3.
Opt Express ; 30(23): 41340-41349, 2022 Nov 07.
Article in English | MEDLINE | ID: mdl-36366614

ABSTRACT

Metasurfaces offer an unprecedented opportunity for flexible manipulation of electromagnetic wave. The azimuth-rotation-independent (ARI) polarization conversion metasurface (PCM) is an ultrathin device, which could convert an arbitrary linearly-polarized incident wave to its cross-polarized state. However, the bandwidth of an ARI PCM with a high cross-polarized transmission is usually limited. Here, a topology optimization method of multi-feature points based on the differential evolution (DE) algorithm is adopted to enhance the bandwidth of the traditional ARI PCM while maintaining a high transmission and polarization conversion ratio. The simulated results of the optimized structure indicate a 2.08 times bandwidth expansion in the cross-polarization conversion compared with the original structure. In addition, the measured results are consistent with the simulated ones and the ARI characteristic is validated. The proposed method provides a promising route for efficient high-performance metasurface designs.

4.
Opt Express ; 30(10): 16009-16019, 2022 May 09.
Article in English | MEDLINE | ID: mdl-36221454

ABSTRACT

Stealth radome (SR), especially with an ultra-broad and nearly transparent window between two absorption bands, plays a crucial role in stealth techniques, antenna radomes, and so on. However, current devices have the defects of narrow transmission bands, high insertion loss, and wide transition bands between the transmission and absorption bands, which are unfavorable for the stealth of broadband radar and communication systems. In this paper, a novel SR with an ultra-broad and high-efficiency inter-absorption band transparent window is proposed by combining broadband resonance lumped circuits with a multi-layer cascaded frequency-selective surface (FSS). The equivalent circuit model (ECM) and transmission line method (TLM) are provided and analyzed as a guideline for the SR design. The SR consists of a resistive lossy layer loaded with wide passband lumped circuits and two stacked lossless FSS layers to collectively achieve the high selectivity and ultra-broad transmission band. Simulated results indicate that the proposed SR exhibits an ultra-broad passband from 8.2 to 11.2 GHz (31%) with transmission amplitude more than 0.85 and two 90% absorption bands over 6.8-7.8 GHz and 12-13 GHz, and the transition bands at both sides are only 0.4 GHz and 0.8 GHz, respectively. Our findings can stimulate the promising applications of SR in broadband stealth devices with integrated ultra-broad communication capability or in other electromagnetic (EM) compatibility facilities.

5.
Opt Express ; 30(22): 40221-40230, 2022 Oct 24.
Article in English | MEDLINE | ID: mdl-36298958

ABSTRACT

In this paper, a novel broadband circularly polarized transmitarray antenna (CPTA) enabled by axial-ratio-improved receiver-transmitter metasurface loaded with parasitic patches is proposed. Split-ring-shaped parasitic patch is utilized to generate an additional resonant mode and significantly broaden the 3-dB axial ratio (AR) bandwidth of proposed receiver/transmitter patches from 6.64% to 15.61%. By cascading the receiver and transmitter with the same polarization and then rotating the cell, Pancharatnam-Berry phase can be exploited for providing a 2π phase shift. As verification, a CPTA prototype integrated with a self-made circularly polarized patch antenna is designed, fabricated, and measured. Experimental results show that the proposed CPTA obtains a 3-dB AR bandwidth of 27.1% from 12.1 to 15.9 GHz and an impedance bandwidth of 20.6% from 12.5 to 15.2 GHz. Additionally, it has a flat gain with a 3-dB gain bandwidth of 18.8% from 12.5 to 15.1 GHz, and a maximum gain of 25.6 dBi at 13.1 GHz is achieved. With the advantages of simple design, wide AR bandwidth, and flat gain performance, the proposed CPTA presents great potential applications in wireless systems.

6.
Opt Express ; 30(5): 8303-8316, 2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35299574

ABSTRACT

In this paper, a conformal optical transparent metamaterial absorber (COTMA) is proposed based on the circuit analog optimization method (CAOM), which can effectively enhance the optimization speed in the metamaterial absorber structure design by quantifying the equivalent circuit parameters. The operating frequency band can be customized at any band through CAOM, such as microwave, terahertz, and near-infrared frequencies. Here, a five-square-patch structure absorber with transparency and flexible properties is achieved. The simulated and measured incident electromagnetic (EM) wave absorptions of COTMA can reach above 90% in 15.77 - 38.69 GHz band. Meanwhile, COTMA exhibits excellent conformal EM absorption, a thinner substrate (0.078 wavelength at 15.77 GHz), lower structure complexity and polarization independence, and it can also be adapted to the EM absorption of different curved screens. This design is expected to have potential applications for wearable electronics, curved surface screens and OLED displays.

7.
Opt Lett ; 47(21): 5708-5711, 2022 Nov 01.
Article in English | MEDLINE | ID: mdl-37219309

ABSTRACT

Surface plasmon polaritons (SPPs) and their counterparts at low frequency (i.e., spoof SPPs) have been attracting a lot of attention recently due to their potential application for routing information with high speeds and bandwidth. To further develop integrated plasmonics, a high-efficiency surface plasmon coupler is required for full elimination of the intrinsic scattering and reflection when exciting the highly confined plasmonic modes, but a solution to this challenge has remained elusive so far. To take on this challenge, here we propose a feasible spoof SPP coupler based on a transparent Huygens' metasurface, which is able to realize more than 90% efficiency in near- and far-field experiments. To be specific, electrical and magnetic resonators are designed separately on both sides of the metasurface to satisfy the impedance-matching condition everywhere, leading to full conversion of plane wave propagation into surface wave propagation. Moreover, a well-optimized plasmonic metal which is able to support an eigen SPP is designed. This proposed high-efficiency spoof SPP coupler based on a Huygens' metasurface may pave the way for the development of high-performance plasmonic devices.

8.
Oncol Lett ; 15(4): 4813-4820, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29541245

ABSTRACT

Although nipple-sparing mastectomy (NSM) is being used more frequently, the oncological safety of NSM remains unclear, particularly in young patients (<35 years). The aim of the present study was to compare the rates of local recurrence (LR), disease-free survival (DFS) and overall survival (OS) in young patients with breast cancer who had undergone NSM or conventional mastectomy (CM). The clinicopathological data of young patients with stage 0-IIB breast cancer who had undergone NSM (163 cases) or CM (194 cases) between 2007 and 2016 were retrospectively analyzed. The log-rank test was used to analyze the differences in the LR, DFS and OS rates between the two groups and multivariate analysis was used to analyze the patient prognostic factors for DFS. The median follow-up time was 49 months. Patients who had undergone CM were more likely to exhibit stage II disease (68.4 vs. 58.3%; P=0.015) and positive lymph nodes (45.9 vs. 33.1%; P=0.014). In the NSM group, LR occurred in 7 (4.3%) cases, systemic recurrence in 15 (9.2%) cases and mortality in 9 (5.5%) cases. In the CM group, LR occurred in 6 (3.1%) cases, systemic recurrence in 27 (13.9%) cases and mortality in 15 (7.7%) cases. There were no statistical differences in the LR, DFS and OS rates between the two groups (P>0.05). Following adjustment for clinical stage, the LR and DFS rates between the two groups exhibited no significant differences. Analysis of the prognostic factors demonstrated that clinical stage, lymph node status, estrogen and progesterone receptor status and human epidermal growth factor receptor 2 status were associated with DFS (P<0.05). NSM is safe for young patients with early-stage breast cancer and provides patients with an improved cosmetic outcome. Furthermore, nipple-areola complex preservation does not increase the risk of recurrence.

9.
Opt Express ; 26(3): 3594-3603, 2018 Feb 05.
Article in English | MEDLINE | ID: mdl-29401887

ABSTRACT

Multifunctional metasurface integrating different functions can significantly save the occupied space, although most of bifunctional metasurfaces reported to date only control the wave in either reflection or transmission regime. In this paper, we propose a scheme that allows one to independently control the reflection and transmission wavefront under orthogonal polarizations. For demonstration, we design a bifunctional metasurface that simultaneously realizes a diffusion reflection and a focusing transmission. The diffusion reflection is realized using a random phase distribution, which was implemented by randomly arranging two basic coding unit cells with the aid of an ergodic algorithm. Meanwhile, the hyperbolic phase distribution was designed to realize the focusing functionality in the transmission regime. To further show the potential applications, a high-gain lens antenna was designed by assembling the proposed metasurface with a proper feed. Both simulation and measurement results have been carried out, and the agreement between the two results demonstrates the validity of the performance as expected. The backward scattering can be reduced more than 5 dB within 6.4-10 GHz compared with the metallic plate. Moreover, the lens antenna has a gain of 20 dB (with around 13 dB enhancement in comparison with the bare feeding antenna) and an efficiency of 32.5%.

10.
Sci Rep ; 7(1): 16560, 2017 11 29.
Article in English | MEDLINE | ID: mdl-29185501

ABSTRACT

This paper proposes an easy, efficient strategy for designing broadband, wide-angle and polarization-independent diffusion metasurface for radar cross section (RCS) reduction. A dual-resonance unit cell, composed of a cross wire and cross loop (CWCL), is employed to enhance the phase bandwidth covering the 2π range. Both oblique-gradient and horizontal-gradient phase supercells are designed for illustration. The numerical results agree well with the theoretical ones. To significantly reduce backward scattering, the random combinatorial gradient metasurface (RCGM) is subsequently constructed by collecting eight supercells with randomly distributed gradient directions. The proposed metasurface features an enhanced specular RCS reduction performance and less design complexity compared to other candidates. Both simulated and measured results show that the proposed RCGM can significantly suppress RCS and exhibits broadband, wide-angle and polarization independence features.

11.
Sci Rep ; 7(1): 11685, 2017 09 15.
Article in English | MEDLINE | ID: mdl-28916819

ABSTRACT

Goubau line is a single-conductor transmission line, featuring easy integration and low-loss transmission properties. Here, we propose a periodic leaky-wave antenna (LWA) based on planar Goubau transmission line on a thin dielectric substrate. The leaky-wave radiations are generated by introducing periodic modulations along the Goubau line. In this way, the surface wave, which is slow-wave mode supported by the Goubau line, achieves an additional momentum and hence enters the fast-wave region for radiations. By employing the periodic modulations, the proposed Goubau line LWAs are able to continuously steer the main beam from backward to forward within the operational frequency range. However, the LWAs usually suffer from a low radiation efficiency at the broadside direction. To overcome this drawback, we explore both transversally and longitudinally asymmetrical modulations to the Goubau line. Theoretical analysis, numerical simulations and experimental results are given in comparison with the symmetrical LWAs. It is demonstrated that the asymmetrical modulations significantly improve the radiation efficiency of LWAs at the broadside. Furthermore, the measurement results agree well with the numerical ones, which experimentally validates the proposed LWA structures. These novel Goubau line LWAs, experimentally demonstrated and validated at microwave frequencies, show also great potential for millimeter-wave and terahertz systems.

12.
Opt Express ; 24(24): 27836-27848, 2016 Nov 28.
Article in English | MEDLINE | ID: mdl-27906352

ABSTRACT

Pancharatnam-Berry (PB) metasurfaces have intrigued a great deal of interest in recent years for anomalous reflection/refraction, vortex plate, orbital angular momentum, flat lens, photonic spin hall effect (PSHE), holograms and reflect/transmit arrays. However, almost all designs are restricted to fixed electrical performance/functionality once the design is finished. Here, we report for the first time a strategy for PB metasurface with agile working frequency by involving each meta-atom with tunable PIN diodes. For verification, a tunable PB metasurface with frequency reconfigurability is designed and numerically characterized across C and X band. By controlling the external voltages imposed on the diodes, numerical results show that the operation band with 180° phase difference between orthogonal reflection coefficients can be dynamically controlled. As such, the resulting PB metasurface composed of these orderly rotated meta-atoms exhibits a broadband PSHE with nearly 100% conversion efficiency in the "On" state while switches to dual well-separated bands in the "Off" state. Our proposal, not confined to PHSE, set a solid platform for PB phase control and can be populated to any dual-functional and/or multifunctional devices with high integrity, stability and low cost.

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