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1.
Opt Express ; 32(7): 11221-11240, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38570975

RESUMO

Laser-guided detector and infrared detection have attracted increasing attention in a wide range of research fields, including multispectral detection, radiative cooling, and thermal management. Previously reported absorbers presented shortcomings of lacking either tunability or compatibility. In this study, a metamaterial perfect absorber based on a Helmholtz resonator and fractal structure is proposed, which realizes tunable perfect absorptivity (α 1.06µ m >0.99,α 10.6µ m >0.99) of guided-laser radar dual operating bands (1.06 µm and 10.6 µm) and a low infrared average emissivity (ε¯3-5µ m =0.03,ε¯8-14µ m =0.31) in two atmospheric windows for compatible camouflage. The proposed perfect absorber provides a dynamically tunable absorptivity without structural changes and can be applied to optical communication, military stealth or protection, and electromagnetic detection.

2.
Opt Express ; 32(3): 3379-3393, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297560

RESUMO

In contrast to conventional emitters fashioned from traditional materials, tunable thermal emitters exhibit a distinct propensity to fulfill the demands of diverse scenarios, thereby engendering an array of prospects within the realms of communications, military applications, and control systems. In this paper, a tunable thermal emitter without continuous external excitation is introduced using Ge2Sb2Te5 (GST) and high-temperature-resistant material Mo. It is automatically optimized by inverse design with genetic algorithm (GA) to switch between different functions according to the object temperature to adapt to diverse scenarios. In "off" mode, the emitter orchestrates a blend of infrared (IR) stealth and thermal management. This is evidenced by average absorptivity values of 0.08 for mid-wave infrared (MIR, 3-5 µm), 0.19 for long-wave infrared (LIR, 8-14 µm), and 0.68 for the non-atmospheric window (NAW, 5-8 µm). Conversely, when confronted with high-temperature entities, the emitter seamlessly transitions to "on" mode, instigating a process of radiative cooling. This transformation is reflected in the augmented emissivity of the dual-band atmospheric window including MIR and LIR, attaining peak values of 0.96 and 0.97. This transition yields a cooling potential, quantified at 64 W/m2 at the ambient temperature of 25°C. In addition, our design employs a layered structure, which avoids complex patterned resonators and facilitates large-area fabrication. The emitter in this paper evinces robust insensitivity to polarization variations and the angle of incidence. We believe that this work will contribute to the development in the fields of dynamic tunability for IR stealth, dynamic radiative cooling systems, and thermal imaging.

3.
Nano Lett ; 24(4): 1238-1245, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38180780

RESUMO

The metasurface analogue of electromagnetically induced transparency (EIT) provides a chip-scale platform for achieving light delay and storage, high Q factors, and greatly enhanced optical fields. However, the literature relies on the coupling between localized and localized or localized and collective resonances, limiting the Q factor and related performance. Here, we report a novel approach for realizing collective EIT-like bands with a measured Q factor reaching 2750 in silicon metasurfaces in the near-infrared regime, exceeding the state of the art by more than 5 times. It employs the coupling between two collective resonances, the Mie electric dipole surface lattice resonance (SLR) and the out-of-plane/in-plane electric quadrupole SLR (EQ-SLR). Remarkably, the collective EIT-like resonance can have diverging Q factor and group delay due to the bound state in the continuum characteristics of the in-plane EQ-SLR. With these findings, our study opens a new route for tailoring light flow in metasurfaces.

4.
Opt Express ; 31(24): 40498-40507, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041349

RESUMO

Multi-soliton operation in fiber lasers is a promising platform for the investigation of soliton interaction dynamics and high repetition-rate pulse. However, owing to the complex interaction process, precisely manipulating the temporal spacing of multiple solitons in a fiber laser is still challenging. Herein, we propose an automatic way to control the temporal spacing of multi-soliton operation in an ultrafast fiber laser by a hybrid genetic algorithm-particle swarm optimization (GA-PSO) algorithm. Relying on the intelligent adjustment of the electronic polarization controller (EPC), the on-demand temporal spacing of the double solitons can be effectively achieved. In particular, the harmonic mode locking with equal temporal spacing of double solitons is also obtained. Our approach provides a promising way to explore nonlinear soliton dynamics in optical systems and optimize the performance of ultrafast fiber lasers.

5.
Opt Express ; 31(22): 35653-35669, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-38017732

RESUMO

In recent years, structural color has developed rapidly due to its distinct advantages, such as low loss, high spatial resolution and environmental friendliness. Various inverse design methods have been extensively investigated to efficiently design optical structures. However, the optimization method for the inverse design of structural color remains a formidable challenge. Traditional optimization approaches, such as genetic algorithms require time-consuming repetitions of structural simulations. Deep learning-assisted design necessitates prior simulations and large amounts of data, making it less efficient for systems with a small number of features. This study proposes a tensor completion algorithm capable of swiftly and accurately predicting missing datasets based on partially obtained datasets to assist in structural color design. Transforming the complex physical problem of structural color design into a spatial structure relationship problem linking geometric parameters and spectral data. The method utilizes tensor multilinear data analysis to effectively capture the complex relationships associated with geometric parameters and spectral data in higher-order data. Numerical and experimental results demonstrate that the algorithm exhibits high reliability in terms of speed and accuracy for diverse structures, datasets of varying sizes, and different materials, significantly enhancing design efficiency. The proposed algorithm offers a viable solution for inverse design problems involving complex physical systems, thereby introducing a novel approach to the design of photonic devices. Additionally, numerical experiments illustrate that the structural color of cruciform resonators with diamond can overcome the high loss issues observed in traditional dielectric materials within the blue wavelength region and enhance the corrosion resistance of the structure. We achieve a wide color gamut and a high-narrow reflection spectrum nearing 1 by this structure, and the theoretical analysis further verifies that diamond holds great promise in the realm of optics.

6.
Opt Express ; 31(20): 33622-33637, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859139

RESUMO

Infrared (IR) thermal camouflage and management are deeply desirable in the field of military and astronomy. While IR compatible with laser camouflage technology is extensively studied to counter modern detection systems, most existing strategies for visible light camouflage focus on color matching, which is not suitable for scenarios requiring transparency. In this work, we propose an optically transparent metamaterial with multi-band compatible camouflage capability based on the inverse design. The metamaterial consists of Ag grating, Si3N4 dielectric spacer layer, Ag reflection layer, and Si3N4 anti-reflective layer. An ideal multi-band compatible spectrum is involved in the inverse design algorithm. Calculated results demonstrate high transmittance (T0.38-0.78µm = 0.70) in the visible region, low reflectance (R1.55µm = 0.01) in laser working wavelength, high reflectance (R3-5µm = 0.86 and R8-14µm = 0.92) in the dual-band atmospheric window, and high emissivity (ɛ5-8µm = 0.61) for the non-atmospheric window. The radiative heat flux in the detected band is 31W/m2 and 201W/m2 respectively. Furthermore, the incident and polarized insensitivity of the proposed metamaterial supports applicability for practical situations. This work, emphasizes an effective strategy for conducting optically transparent design with compatible IR-laser camouflage as well as radiative cooling properties by an automated design approach.

7.
J Minim Access Surg ; 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37706413

RESUMO

Introduction: To assess the feasibility and safety of placing a small-sized tube as drainage in patients after uniportal thoracoscopic lung resection. Patients and Methods: Patients who received uniportal video-assisted thoracoscopic surgery (U-VATS) lung resection were identified in our database. Patients placed small-sized tube drainage were compared with those placed conventional chest tube in terms of characteristics, operation modality, post-operative pulmonary complications, post-operative pain, chest tube duration and post-operative hospital stay. Propensity score matching was performed. Results: Of the 217 enrolled patients, 173 were assigned to the conventional tube group and 44 were assigned to the small-sized tube group. Rates of post-operative pulmonary complications were relatively low and similar between the two groups. After propensity score matching, operation duration was shorter (1 h vs. 1.21 h, P = 0.01) was shorter, and the maximum value of the Visual Analogue Scale (VAS) score after operation (1 vs. 1.5, P = 0.02) and the overall average value of VAS score after operation (0.33 vs. 0.88, P = 0.006) was lower in small-sized tube group. No significant difference was observed in chest tube duration (2 vs. 2, P = 0.34) and post-operative hospital stay (3 vs. 3, P = 0.34). Conclusions: Compared to conventional chest tubes, small-sized tubes for post-operative drainage after U-VATS lung resection may be a safe and promising approach for reducing post-operative pain.

8.
Sensors (Basel) ; 23(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37631664

RESUMO

Fiber-optic magnetic field sensors have garnered considerable attention in the field of marine monitoring due to their compact size, robust anti-electromagnetic interference capabilities, corrosion resistance, high sensitivity, ease of multiplexing and integration, and potential for large-scale sensing networks. To enable the detection of marine magnetic field vector information, we propose an optical fiber vector magnetic field sensor that integrates three single-axis sensors in an orthogonal configuration. Theoretical analysis and experimental verification are conducted to investigate its magnetic field and temperature sensing characteristics, and a sensitivity matrix is established to address the cross-sensitivity between the magnetic field and temperature; experimental tests were conducted to assess the vector response of the three-dimensional (3D) vector sensor across the three orthogonal axes; the obtained experimental results illustrate the commendable magnetic field vector response exhibited by the sensor in the orthogonal axes, enabling precise demodulation of vector magnetic field information. This sensor presents several advantages, including cost-effectiveness, easy integration, and reliability vectorially. Consequently, it holds immense potential for critical applications in marine magnetic field network detection.

10.
World J Surg Oncol ; 21(1): 232, 2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37516847

RESUMO

BACKGROUND: This study aimed to demonstrate the learning curve of anatomical segmentectomy performed by uniportal video-assisted thoracoscopic surgery (U-VATS). METHOD: We conducted a retrospective study of U-VATS segmentectomies performed by the same surgeon between September 2019 and August 2022. The learning curve was demonstrated using risk-adjusted cumulative sum (RA-CUSUM) analysis in terms of perioperative complications, which reflected surgical quality and technique proficiency. The surgical outcomes were also compared between different phases. RESULT: The complication-based learning curve of U-VATS segmentectomy could be divided into two phases based on RA-CUSUM analysis: phase I, the initial learning phase (cases 1-50) and phase II, the proficiency phase (cases 51-141). Significantly higher complication rates (24.0 vs. 8.8%, p=0.013), longer surgical times (119.8±31.9 vs. 106.2±23.8 min, p=0.005), and more blood loss (20 [IQR, 20-30] vs. 20 [IQR, 10-20] ml, p=0.003) were observed in phase I than in phase II. CONCLUSION: The learning curve of U-VATS segmentectomy consists of two phases, and at least 50 cases were required to gain technique proficiency and achieve high-quality surgical outcomes.


Assuntos
Curva de Aprendizado , Cirurgiões , Humanos , Mastectomia Segmentar , Estudos Retrospectivos , Duração da Cirurgia
11.
Sensors (Basel) ; 23(10)2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37430570

RESUMO

In the process of ocean exploration, highly accurate and sensitive measurements of seawater temperature and pressure significantly impact the study of seawater's physical, chemical, and biological processes. In this paper, three different package structures, V-shape, square-shape, and semicircle-shape, are designed and fabricated, and an optical microfiber coupler combined Sagnac loop (OMCSL) is encapsulated in these structures with polydimethylsiloxane (PDMS). Then, the temperature and pressure response characteristics of the OMCSL, under different package structures, are analyzed by simulation and experiment. The experimental results show that structural change hardly affects temperature sensitivity, and square-shape has the highest pressure sensitivity. In addition, with an input error of 1% F.S., temperature and pressure errors were calculated, which shows that a semicircle-shape structure can increase the angle between lines in the sensitivity matrix method (SMM), and reduce the effect of the input error, thus optimizing the ill-conditioned matrix. Finally, this paper shows that using the machine learning method (MLM) effectively improves demodulation accuracy. In conclusion, this paper proposes to optimize the ill-conditioned matrix problem in SMM demodulation by improving sensitivity with structural optimization, which essentially explains the cause of the large errors for multiparameter cross-sensitivity. In addition, this paper proposes to use the MLM to solve the problem of large errors in the SMM, which provides a new method to solve the problem of the ill-conditioned matrix in SMM demodulation. These have practical implications for engineering an all-optical sensor that can be used for detection in the ocean environment.

12.
Biol Direct ; 18(1): 33, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37337223

RESUMO

BACKGROUND: Proteasome 26S subunit, non-ATPase 3 (PSMD3) has been reported to participate in various human cancers. Nevertheless, the function of PSMD3 in lung cancer (LC) remains unclear. METHODS: RT-qPCR and western blot were used to detect the expression of PSMD3 in LC tissues form TCGA database and clinical samples, and LC cell lines. To study the effect of PSMD3 on LC cell proliferation, migration, invasion, and apoptosis, siRNAs targeting PSMD3 were synthesized and overexpressed plasmids were constructed. CCK-8 assay, Transwell assay, and etc. were used to evaluate the results. Tumor xenograft model was used to evaluate the function of PSMD3 on tumor growth. CO-IP and MS were used to scan the proteins that bind with PSMD3. The interaction between PSMD3 and ILF3 in lung cancer cells were studied using IF staining, CHX protein stability, and ubiquitination assay. Additionally, the effect of ILF3 on cell progression and LC tumor growth was demonstrated by conducting a recovery assay using siILF3 and an ILF3 inhibitor YM155. RESULTS: We observed that PSMD3 was significantly overexpressed in LC tissues and cells, which indicated a poor prognosis. Meanwhile, we found that PSMD3 promoted cell proliferation, migration, and invasion of LC cells. We also determined that PSMD3 stabilized the protein expression of ILF3 and the deubiquitination of ILF3 in lung cancer cells. Furthermore, animal experiments showed that the ILF3 inhibitor YM155 could suppress tumor growth with the presence of PSMD3. CONCLUSIONS: PSMD3 collectively regulated the stability of ILF3 protein and facilitated the ubiquitination of endogenous ILF3 in LC, which ultimately promoted the progression of LC cells. The PSMD3/ ILF3 axis could potentially be used as a novel strategy for both diagnosis and treatment of LC.


Assuntos
Neoplasias Pulmonares , Proteínas do Fator Nuclear 90 , Complexo de Endopeptidases do Proteassoma , Animais , Humanos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Proteínas do Fator Nuclear 90/genética , Proteínas do Fator Nuclear 90/metabolismo , Transdução de Sinais , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo
13.
Opt Express ; 31(7): 11913-11922, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37155815

RESUMO

Low-cost, short-range optical interconnect technology plays an indispensable role in high-speed board-level data communications. In general, 3D printing technology can easily and quickly produce optical components with free-form shapes, while the traditional manufacturing process is complicated and time-consuming. Here, we present a direct ink writing 3D-printing technology to fabricate optical waveguides for optical interconnects. The waveguide core is 3D printed optical polymethylmethacrylate (PMMA) polymer, with propagation loss of 0.21 dB/cm at 980 nm, 0.42 dB/cm at 1310 nm, and 1.08 dB/cm at 1550 nm, respectively. Furthermore, a high-density multilayer waveguide arrays, including a four-layer waveguide arrays with a total of 144 waveguide channels, is demonstrated. Error-free data transmission at 30 Gb/s is achieved for each waveguide channel, indicating that the printing method can produce optical waveguides with excellent optical transmission performance. We believe this simple, low-cost, highly flexible, and environmentally friendly method has great potential for high-speed short-range optical interconnects.

14.
Opt Express ; 31(10): 16795-16811, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157751

RESUMO

Metal coatings can protect the fragile optical fiber sensors and extend their life in harsh environments. However, simultaneous high-temperature strain sensing in a metal-coated optical fiber remains relatively unexplored. In this study, a nickel-coated fiber Bragg grating (FBG) cascaded with an air bubble cavity Fabry-Perot interferometer (FPI) fiber optic sensor was developed for simultaneous high temperature and strain sensing. The sensor was successfully tested at 545 °C for 0-1000 µÉ›, and the characteristic matrix was used to decouple temperature and strain. The metal layer allows easy attachment to metal surfaces that operate at high temperatures, enabling sensor-object integration. As a result, the metal-coated cascaded optical fiber sensor has the potential to be used in real-world structural health monitoring.

15.
Nanomaterials (Basel) ; 13(9)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37176996

RESUMO

Color displays have become increasingly attractive, with dielectric optical nanoantennas demonstrating especially promising applications due to the high refractive index of the material, enabling devices to support geometry-dependent Mie resonance in the visible band. Although many structural color designs based on dielectric nanoantennas employ the method of artificial positive adjustment, the design cycle is too lengthy and the approach is non-intelligent. The commonly used phase change material Ge2Sb2Te5 (GST) is characterized by high absorption and a small contrast to the real part of the refractive index in the visible light band, thereby restricting its application in this range. The Sb2S3 phase change material is endowed with a wide band gap of 1.7 to 2 eV, demonstrating two orders of magnitude lower propagation loss compared to GST, when integrated onto a silicon waveguide, and exhibiting a maximum refractive index contrast close to 1 at 614 nm. Thus, Sb2S3 is a more suitable phase change material than GST for tuning visible light. In this paper, genetic algorithms and finite-difference time-domain (FDTD) solutions are combined and introduced as Sb2S3 phase change material to design nanoantennas. Structural color is generated in the reflection mode through the Mie resonance inside the structure, and the properties of Sb2S3 in different phase states are utilized to achieve tunability. Compared to traditional methods, genetic algorithms are superior-optimization algorithms that require low computational effort and a high population performance. Furthermore, Sb2S3 material can be laser-induced to switch the transitions of the crystallized and amorphous states, achieving reversible color. The large chromatic aberration ∆E modulation of 64.8, 28.1, and 44.1 was, respectively, achieved by the Sb2S3 phase transition in this paper. Moreover, based on the sensitivity of the structure to the incident angle, it can also be used in fields such as angle-sensitive detectors.

16.
Sensors (Basel) ; 23(7)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37050450

RESUMO

The magnetic field is a vital physical quantity in nature that is closely related to human production life. Magnetic field sensors (namely magnetometers) have significant application value in scientific research, engineering applications, industrial productions, and so forth. Accompanied by the continuous development of magnetic materials and fiber-sensing technology, fiber sensors based on the Magneto-Refractive Effect (MRE) not only take advantage in compact structure, superior performance, and strong environmental adaptability but also further meet the requirement of the quasi-distributed/distributed magnetic field sensing; they manifest potential and great application value in space detection, marine environmental monitoring, etc. Consequently, the present and prevalent Magneto-Refractive Magnetic Field Fiber Sensors (MR-MFSs) are briefly summarized by this paper, proceeding from the perspective of physicochemical properties; design methods, basic performance and properties are introduced systematically as well. Furthermore, this paper also summarizes key fabrication techniques and future development trends of MR-MFSs, expecting to provide ideas and technical references for staff engaging in relevant research.

17.
Opt Express ; 31(5): 8668-8681, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36859977

RESUMO

Metalens with extended depth of focus (EDOF) can extend the mapping area of the image, which leads to novel applications in imaging and microscopy. Since there are still some disadvantages for existing EDOF metalenses based on forward design, such as asymmetric point spread function (PSF) and non-uniformly distributed focal spot, which impair the quality of images, we propose a double-process genetic algorithm (DPGA) optimization to inversely design the EDOF metalens for addressing these drawbacks. By separately adopting different mutation operators in successive two genetic algorithm (GA) processes, DPGA exhibits significant advantages in searching for the ideal solution in the whole parameter space. Here, the 1D and 2D EDOF metalenses operating at 980 nm are separately designed via this method, and both of them exhibit significant depth of focus (DOF) improvement to that of conventional focusing. Furthermore, a uniformly distributed focal spot can be maintained well, which can guarantee stable imaging quality along the longitudinal direction. The proposed EDOF metalenses have considerable potential applications in biological microscopy and imaging, and the scheme of DPGA can be promoted to the inverse design of other nanophotonics devices.

18.
Opt Express ; 31(5): 9112-9122, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36860010

RESUMO

On-line gas detection under strong impact such as combustion and explosion is of great significance for understanding the reaction processes. To realize simultaneous on-line detection of various gases under strong impact, an approach based on optical multiplexing for enhancing spontaneous Raman scattering is proposed. A single beam is transmitted several times using optical fibers through a specific measurement point in the reaction zone. Thus, the excitation light intensity at the measurement point is enhanced and the Raman signal intensity is substantially increased. Indeed, the signal intensity can be increased by a factor of ∼10, and the constituent gases in air can be detected with sub-second time resolution, under a 100 g impact.

19.
Front Surg ; 10: 1102352, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36793311

RESUMO

Objective: A large number of patients with pulmonary ground-glass opacities (GGOs) have anxiety and depression. However, the contributing factors and effects of anxiety and depression on postoperative outcomes are still unclear. Methods: Clinical data for patients undergoing surgical resection for pulmonary GGOs were collected. We prospectively evaluated levels and risk factors for anxiety and depression in patients with GGOs before surgery. The relationship between psychological disorders and postoperative morbidity was evaluated. Quality of life (QoL) was also assessed. Results: A total of 133 patients were enrolled. Prevalence rates of preoperative anxiety and depression were 26.3% (n = 35) and 18% (n = 24), respectively. Multivariate analysis revealed depression [odds ratio(OR) = 16.27, p < 0.001] and multiple GGOs (OR = 3.146, p = 0.033) to be risk factors for preoperative anxiety. Anxiety (OR = 52.166, p < 0.001), age > 60 (OR = 3.601, p = 0.036), and unemployment (OR = 8.248, p = 0.006) were identified as risk factors for preoperative depression. Preoperative anxiety and depression were associated with lower QoL and higher postoperative pain scores. Our results also revealed that the incidence of postoperative atrial fibrillation was higher in patients with than in those without anxiety. Conclusions: In patients with pulmonary GGOs, comprehensive psychological assessment and appropriate management are required before surgery to improve QoL and reduce postoperative morbidity.

20.
Opt Express ; 31(2): 2902-2910, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785293

RESUMO

The self-starting performance of a figure-9 fiber laser is critically dependent on the phase shift difference between the counter-propagating beams. Herein, we propose an effective approach to dynamically control the phase shift difference in a figure-9 fiber laser by utilizing the thermal nonlinearity of graphene-decorated microfiber device. With the adjustment of the control laser power injected into the graphene-decorated microfiber, the self-starting mode-locked threshold of the figure-9 fiber laser can be attained in a flexible pump power range, i.e., from 300 mW to 390 mW. These findings demonstrated that the graphene-decorated microfiber could act as a dynamical control device of phase shift difference for improving the performance of figure-9 fiber lasers, and might also open up new possibilities for applications of microfiber photonic devices in the field of ultrafast optics.

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