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1.
Nat Commun ; 15(1): 3055, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38594345

ABSTRACT

Providing additional degrees of freedom to manipulate light, spatiotemporal optical vortex (STOV) beams carrying transverse orbital angular momentum are of fundamental importance for spatiotemporal control of light-matter interactions. Unfortunately, existing methods to generate STOV are plagued by various limitations such as inefficiency, bulkiness, and complexity. Here, we theoretically propose and experimentally demonstrate a microscale singlet platform composed of a slanted nanograting to generate STOV. Leveraging the intrinsic topological singularity induced by C2 symmetry and z-mirror symmetry breaking of the slanted nanograting, STOV is generated through the Fourier transform of the spiral phase in the momentum-frequency space to the spatiotemporal domain. In experiments, we observe the space-time evolution of STOV carried by femtosecond pulses using a time-resolved interferometry technique and achieve a generation efficiency exceeding 40%. Our work sheds light on a compact and versatile platform for light pulse shaping, and paves the way towards a fully integrated system for spatiotemporal light manipulation.

2.
J Periodontal Res ; 59(2): 249-258, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38115631

ABSTRACT

OBJECTIVE: To assess the effects of amoxicillin and metronidazole with scaling and root planing (SRP) on periodontal parameters and glycemic control in patients with severe periodontitis and diabetes mellitus. BACKGROUND: Adjunctive antibiotics use is advantageous for treating periodontitis in patients with severe periodontitis and diabetes. However, the effects of adjunctive antibiotic use on hemoglobin A1c (HbA1c) levels remain unclear. METHODS: This short-term, randomized controlled trial enrolled patients with severe periodontitis and type 2 diabetes. The patients were randomly allocated to SPR only (i.e., control) or SPR + antibiotics (500 mg of amoxicillin and 200 mg of metronidazole, three times daily for 7 days) groups. Periodontal and hematological parameters were assessed at baseline and 3 months after treatment. Inter- and intra-group analyses were performed using Student's t-tests, Mann-Whitney U tests, and the binary logistic regression models. p-values of <.05 were considered statistically significant. RESULTS: This study enrolled 49 patients, with 23 and 26 patients in the SRP-only and SRP + antibiotics groups, respectively. The periodontal parameters improved significantly and similarly in both groups after treatment (p < .05). The SRP + antibiotics group had more sites of improvement than the SRP-only group when the initial probing depth was >6 mm. (698 [78.96%] vs. 545 [73.35%], p = .008). The HbA1c levels decreased in the SRP-only and SRP + antibiotics groups after treatment (0.39% and 0.53%, respectively). The multivariable binary logistic regression model demonstrated that antibiotics administration and a high baseline HbA1c level were associated with a greater reduction in the HbA1c level (odds ratio = 4.551, 95% confidence interval: 1.012-20.463; odds ratio = 7.162, 95% confidence interval: 1.359-37.753, respectively). CONCLUSIONS: SRP and SRP plus systemic antibiotics were beneficial for glycemic control. Adjunctive antibiotic use slightly improved the outcome for patients with severe periodontitis and poorly controlled diabetes.


Subject(s)
Chronic Periodontitis , Diabetes Mellitus, Type 2 , Periodontitis , Humans , Metronidazole/therapeutic use , Amoxicillin/therapeutic use , Root Planing , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Glycemic Control , Glycated Hemoglobin , Treatment Outcome , Anti-Bacterial Agents/therapeutic use , Periodontitis/complications , Periodontitis/drug therapy , Dental Scaling , Chronic Periodontitis/drug therapy
3.
Opt Lett ; 48(17): 4709-4712, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37656592

ABSTRACT

Metasurfaces have recently emerged as a crucial tool because they achieve spherical-aberration-free focusing when exposed to normal incident light. Nevertheless, these metasurfaces often exhibit considerable coma when subjected to oblique incident light, thereby limiting their imaging field of view. In light of this, our study presents the design and an experimental demonstration of a polarization-insensitive, large-field-of-view metalens that uses a silicon metasurface. The metalens is specifically tailored to the long-wavelength infrared region and possesses a numerical aperture of 0.81, which is capable of focusing light at incident angles up to ±80°. Moreover, we successfully build a meta-optics camera by integrating the large field-of-view metalens on top of an image sensor, thus enabling wide-angle thermal imaging of practical scenes. This research provides new, to the best of our knowledge, insights for designing and realizing large-field-of-view optical systems and holds promise for applications in night vision imaging and security monitoring.

4.
Mol Oral Microbiol ; 38(4): 309-320, 2023 08.
Article in English | MEDLINE | ID: mdl-37216657

ABSTRACT

INTRODUCTION: MicroRNAs (miRNAs), a type of non-coding RNA, have been demonstrated to be essential posttranscriptional modulators in oral diseases and inflammatory responses. However, the specific role of miR-27a-5p in periodontitis requires further investigation. In this study, we used both cellular and animal models to determine how miR-27a-5p affects the pathogenesis of periodontitis and its associated biological functions. METHODS: Quantitative real-time polymerase chain reaction and western blotting were used to analyze the expression of cytokines, phosphatase and tensin homolog deleted on chromosome ten (PTEN), and miR-27a-5p transcription. Investigation of alveolar bone resorption and inflammation of the periodontium in ligature-induced periodontitis in mice was performed using micro-computed tomography (micro-CT), hematoxylin-eosin (HE) staining, and tartrate-resistant acid phosphatase (TRAP) staining. The binding of miR-27a-5p and PTEN was predicted using the TargetScan database and experimentally confirmed using dual luciferase reporter gene assays. RESULTS: The inflamed gingiva showed lower levels of miR-27a-5p. Macrophages from miR-27a-5p-/- mice produced much higher quantities of pro-inflammatory cytokines owing to the stimulation of Porphyromonas gingivalis lipopolysaccharide, and miR-27a-5p-/- mice with ligature-induced periodontitis also exhibited more severe alveolar bone resorption and damage to the periodontium. Target validation assays identified PTEN as a direct target of bona. Blocking PTEN expression partially reduced inflammation, both in vitro and in vivo. CONCLUSIONS: miR-27a-5p alleviated the inflammatory response in periodontitis by targeting PTEN.


Subject(s)
Bone Resorption , MicroRNAs , Periodontitis , Mice , Animals , Tensins/genetics , X-Ray Microtomography , MicroRNAs/genetics , MicroRNAs/metabolism , Inflammation , PTEN Phosphohydrolase/genetics , PTEN Phosphohydrolase/metabolism , Cytokines/genetics , Periodontitis/genetics , Chromosomes/metabolism , Bone Resorption/genetics
5.
Nano Lett ; 23(7): 2991-2997, 2023 Apr 12.
Article in English | MEDLINE | ID: mdl-36971648

ABSTRACT

Spiral phase contrast imaging and bright-field imaging are two widely used modes in microscopy, providing distinct morphological information about objects. However, conventional microscopes are always unable to operate with these two modes at the same time and need additional optical elements to switch between them. Here, we present a microscopy setup that incorporates a dielectric metasurface capable of achieving spiral phase contrast imaging and bright-field imaging synchronously. The metasurface not only can focus the light for diffraction-limited imaging but also can perform a two-dimensional spatial differentiation operation by imparting an orbital angular momentum to the incident light field. This allows two spatially separated images to be simultaneously obtained, one containing high-frequency edge information and the other showing the entirety of the object. Combined with the advantages of planar architecture and ultrathin thickness of the metasurface, this approach is expected to provide support in the fields of microscopy, biomedicine, and materials science.

6.
Natl Sci Rev ; 10(1): nwac120, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36825119

ABSTRACT

Display and power supply have been two essential and independent cornerstones of modern electronics. Here, we report a lithium-plasmon-based low-powered dynamic color display with intrinsic dual functionality (plasmonic display and energy recycling unit) which is a result of the electric-field-driven transformation of nanostructured lithium metals. Dynamic color displays are enabled by plasmonic transformation through electrodeposition (electrostripping) of lithium metals during the charging (discharging) process, while the consumed energy for coloring can be retrieved in the inverse process respectively. Energy recycling of lithium metals brings energy consumption down to 0.390 mW cm-2 (0.105 mW cm-2) for the active (static) coloration state of a proof-of-concept display/battery device, which approaches nearly-zero-energy-consumption in the near-100%-energy-efficiency limit of commercial lithium batteries. Combining the subwavelength feature of plasmonics with effective energy recycling, the lithium-plasmon-based dynamic display offers a promising route towards next-generation integrated photonic devices, with the intriguing advantages of low energy consumption, a small footprint and high resolution.

7.
Nano Lett ; 23(6): 2436-2441, 2023 Mar 22.
Article in English | MEDLINE | ID: mdl-36723626

ABSTRACT

The electron vortex beam (EVB)-carrying quantized orbital angular momentum (OAM) plays an essential role in a series of fundamental research. However, the radius of the transverse intensity profile of a doughnut-shaped EVB strongly depends on the topological charge of the OAM, impeding its wide applications in electron microscopy. Inspired by the perfect vortex in optics, herein, we demonstrate a perfect electron vortex beam (PEVB), which completely unlocks the constraint between the beam size and the beam's OAM. We design nanoscale holograms to generate PEVBs carrying different quanta of OAM but exhibiting almost the same beam size. Furthermore, we show that the beam size of the PEVB can be readily controlled by only modifying the design parameters of the hologram. The generation of PEVB with a customized beam size independent of the OAM can promote various in situ applications of free electrons carrying OAM in electron microscopy.

8.
Nat Nanotechnol ; 18(1): 71-78, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36471110

ABSTRACT

The growing interest to develop modern digital displays and colour printing has driven the advancement of colouration technologies with remarkable speed. In particular, metasurface-based structural colouration shows a remarkable high colour saturation, wide gamut palette, chiaroscuro presentation and polarization tunability. However, previous approaches cannot simultaneously achieve all these features. Here, we design and experimentally demonstrate a surface-relief plasmonic metasurface consisting of shallow nanoapertures that enable the independent manipulation of colour hue, saturation and brightness by individually varying the geometric dimensions and orientation of the nanoapertures. We fabricate microscale artworks using a reusable template-stripping technique that features photorealistic and stereoscopic impressions. In addition, through the meticulous arrangement of differently oriented nanoapertures, kaleidoscopic information states can be decrypted by particular combinations of incident and reflected polarized light.

9.
Sci Adv ; 8(43): eabq8314, 2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36288319

ABSTRACT

The ability to control the instantaneous state of light, from high-energy pulses down to the single-photon level, is an indispensable requirement in photonics. This has, for example, facilitated spatiotemporal probing and coherent control of ultrafast light-matter interactions, and enabled capabilities such as generation of exotic states of light with complexity, or at wavelengths, that are not easily accessible. Here, by leveraging the multifunctional control of light at the nanoscale offered by metasurfaces embedded in a Fourier transform setup, we present a versatile approach to synthesize ultrafast optical transients with arbitrary control over its complete spatiotemporal evolution. Our approach, supporting an ultrawide bandwidth with simultaneously high spectral and spatial resolution, enables ready synthesis of complex states of structured space-time wave packets. We expect our results to offer unique capabilities in coherent ultrafast light-matter interactions and facilitate applications in microscopy, communications, and nonlinear optics.

10.
Nano Lett ; 22(16): 6655-6663, 2022 Aug 24.
Article in English | MEDLINE | ID: mdl-35925801

ABSTRACT

The miniaturization and integration of optoelectronic devices require progressive size reduction of active layers, resulting in less optical absorption and lower quantum efficiency. In this work, we demonstrate that introducing a metasurface made of hybrid organic-inorganic perovskite (HOIP) can significantly enhance broadband absorption and improve photon-to-electron conversion, which roots from exciting Mie resonances together with suppressing optical transmission. On the basis of the HOIP metasurface, a broadband photodetector has been fabricated where photocurrent boosts more than 10 times in the frequency ranging from ultraviolet to visible. The device response time is less than 5.1 µs at wavelengths 380, 532, and 710 nm, and the relevant 3 dB bandwidth is over 0.26 MHz. Moreover, this photodetector has been applied as a signal receiver for transmitting 2D color images in broadband optical communication. These results accentuate the practical applications of HOIP metasurfaces in novel optoelectronic devices for broadband optical communication.

11.
ACS Appl Mater Interfaces ; 14(8): 10805-10814, 2022 Mar 02.
Article in English | MEDLINE | ID: mdl-35175726

ABSTRACT

With the development of high-performance supercapacitors, a conductive polymer (CP)-based pseudocapacitance electrode with good electrical conductivity and low processing costs holds a promising application prospect. As the core component of supercapacitors, the CP electrode with adjustable spacing, a high specific surface area, and a faster ion diffusion path has been extensively investigated. Herein, based on accurate top-down photolithography and electropolymerization approaches, we fabricate a CP-coated vertically aligned micropillar array (MPA) electrode. The electrode presents an overwhelming enhanced areal specific capacitance compared with that of a flat configuration, which is partially ascribed to an increased electroactive surface area, two rapid channels for ion diffusion and electron transfer, and enhanced electric field intensity that is provided by the MPA structure. Based on the fabricated CP-based MPA electrode, an asymmetric supercapacitor is assembled with two thiophene derivatives, presenting a high energy density and excellent cycling stability. A supercapacitor system cascading with three asymmetric supercapacitor devices further demonstrates the practical applications by driving the light-emitting diodes. This work provides a good reference for the further development of CP-based energy storage devices with high energy density and superior cycling stability.

12.
Light Sci Appl ; 10(1): 107, 2021 May 25.
Article in English | MEDLINE | ID: mdl-34035215

ABSTRACT

Monochromatic light can be characterized by its three fundamental properties: amplitude, phase, and polarization. In this work, we propose a versatile, transmission-mode all-dielectric metasurface platform that can independently manipulate the phase and amplitude for two orthogonal states of polarization in the visible frequency range. For proof-of-concept experimental demonstration, various single-layer metasurfaces composed of subwavelength-spaced titanium-dioxide nanopillars are designed, fabricated, and characterized to exhibit the ability of polarization-switchable multidimensional light-field manipulation, including polarization-switchable grayscale nanoprinting, nonuniform cylindrical lensing, and complex-amplitude holography. We envision the metasurface platform demonstrated here to open new possibilities toward creating compact multifunctional optical devices for applications in polarization optics, information encoding, optical data storage, and security.

13.
Nat Commun ; 12(1): 2230, 2021 Apr 13.
Article in English | MEDLINE | ID: mdl-33850114

ABSTRACT

The term Poincaré beam, which describes the space-variant polarization of a light beam carrying spin angular momentum (SAM) and orbital angular momentum (OAM), plays an important role in various optical applications. Since the radius of a Poincaré beam conventionally depends on the topological charge number, it is difficult to generate a stable and high-quality Poincaré beam by two optical vortices with different topological charge numbers, as the Poincaré beam formed in this way collapses upon propagation. Here, based on an all-dielectric metasurface platform, we experimentally demonstrate broadband generation of a generalized perfect Poincaré beam (PPB), whose radius is independent of the topological charge number. By utilizing a phase-only modulation approach, a single-layer spin-multiplexed metasurface is shown to achieve all the states of PPBs on the hybrid-order Poincaré Sphere for visible light. Furthermore, as a proof-of-concept demonstration, a metasurface encoding multidimensional SAM and OAM states in the parallel channels of elliptical and circular PPBs is implemented for optical information encryption. We envision that this work will provide a compact and efficient platform for generation of PPBs for visible light, and may promote their applications in optical communications, information encryption, optical data storage and quantum information sciences.

14.
Materials (Basel) ; 13(18)2020 Sep 08.
Article in English | MEDLINE | ID: mdl-32911692

ABSTRACT

AlSi10Mg alloy branches were fabricated by selective laser melting (SLM), and the branches were employed to evaluate their effect on the mechanical properties. When the porous branches were compressed along its building direction, the tree column structures-type AlSi10Mg alloy branches collapsed twice, which had typical elastic, shear, collapse, and densification stages. The compressive stress concentration at the interface between the support and the porous body caused the fracture of the tree column structures-type AlSi10Mg alloy branches. The fracture surface indicated that the prepared tree-type branches were distributed with different shapes of dimples, and the Si content inside the dimples was higher than that of the edge. The morphology of the Al-Si eutectic structure formed by SLM and the stress concentration at the Al/Al-Si-eutectic interface affected the fracture morphology and Si content distribution.

15.
Nano Lett ; 20(4): 2791-2798, 2020 04 08.
Article in English | MEDLINE | ID: mdl-32155076

ABSTRACT

As the two most representative operation modes in an optical imaging system, bright-field imaging and phase contrast imaging can extract different morphological information on an object. Developing a miniature and low-cost system capable of switching between these two imaging modes is thus very attractive for a number of applications, such as biomedical imaging. Here, we propose and demonstrate that a Fourier transform setup incorporating an all-dielectric metasurface can perform a two-dimensional spatial differentiation operation and thus achieve isotropic edge detection. In addition, the metasurface can provide two spin-dependent, uncorrelated phase profiles across the entire visible spectrum. Therefore, based on the spin-state of incident light, the system can be used for either diffraction-limited bright-field imaging or isotropic edge-enhanced phase contrast imaging. Combined with the advantages of planar architecture and ultrathin thickness of the metasurface, we envision this approach may open new vistas in the very interdisciplinary field of imaging and microscopy.


Subject(s)
Microscopy, Phase-Contrast/instrumentation , Equipment Design , Fourier Analysis , Light , Optical Imaging/instrumentation , Photons
16.
Optica ; 7(9)2020.
Article in English | MEDLINE | ID: mdl-33655018

ABSTRACT

We realize a dielectric metasurface that enables full-color generation and ultrasmooth brightness variation. The reproduced artwork "Girl with a Pearl Earring" features photorealistic color representation and stereoscopic image impression, mimicking the texture of an oil-painting.

17.
Laser Photon Rev ; 14(9)2020.
Article in English | MEDLINE | ID: mdl-33569085

ABSTRACT

Light beams carrying spin angular momentum (SAM) and orbital angular momentum (OAM) have created novel opportunities in the areas of optical communications, imaging, micromanipulation and quantum optics. However, complex optical setups are required to simultaneously manipulate, measure and analyze these states, which significantly limits system integration. Here, we introduce a novel detection approach for measuring multiple SAM and OAM modes simultaneously through a planar nanophotonic demultiplexer based on an all-dielectric metasurface. Coaxial light beams carrying multiple SAM and OAM states of light upon transmission through the demultiplexer are spatially separated into a range of vortex beams with different topological charge, each propagating along a specific wavevector. The broadband response, material dispersion and momentum conservation further enable the demultiplexer to achieve wavelength demultiplexing. We envision the ultracompact multifunctional architecture to enable simultaneous manipulation and measurement of polarization and spin encoded photon states with applications in integrated quantum optics and optical communications.

18.
Adv Mater ; 32(27): e1903787, 2020 Jul.
Article in English | MEDLINE | ID: mdl-31566259

ABSTRACT

Recent advances in nanofabrication technologies have spurred many breakthroughs in the field of photonic metamaterials that provide efficient ways of manipulating light-matter interaction at subwavelength scales. As one of the most important applications, photonic metamaterials can be used to implement novel optical absorbers. First the morphology engineering of various photonic metamaterial absorbers is discussed, which is highly associated with impendence matching conditions and resonance modes of the absorbers, thus directly determines their absorption efficiency, operational bandwidth, incident angle, and polarization dependence. Then, the recent achievements of various interdisciplinary applications based on photonic metamaterial absorbers, including structural color generation, ultrasensitive optical sensing, solar steam generation, and highly responsive photodetection, are reviewed. This report is expected to provide an overview and vision for the future development of photonic metamaterial absorbers and their applications in novel nanophotonic systems.

19.
Nanoscale ; 11(22): 10646-10654, 2019 Jun 06.
Article in English | MEDLINE | ID: mdl-31107482

ABSTRACT

Optical polarization topology is a spatially varying polarization structure, which usually exists around the polarization singularity. In three-dimensional (3D) space, optical polarization topologies mainly contain two fundamental structures, Möbius strip and twisted ribbon, depending on the parity of half-twist number. These spectacular topologies have been widely found in the existence of electric fields from multi-beam interference. Here, we propose and numerically demonstrate that, depending on the photonic spin state of light, an ultrathin all-dielectric metasurface can achieve efficient generation and transformation of two arbitrary 3D polarization topologies. The spin-controlled, tightly-focused Poincaré beams generated by the metasurface exhibit topologically stable 3D polarization topologies around the waist of the focal point. The preparation of such optical polarization topologies may have potential applications in compact complex beam engineering, optical signal multiplexing and optical fabrication of microstructures with nontrivial topology.

20.
Arch Oral Biol ; 103: 26-32, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31128439

ABSTRACT

OBJECTIVE: Type 2 diabetes mellitus (T2DM) is a complex disease influenced by genes and the environment. Periodontitis a demonstrated risk factor of T2DM. Previous studies related to gene-environment interactions on the risk of T2DM mainly focused on gene-obesity interactions. However, the impact of gene-periodontitis interaction on the risk of T2DM has not yet been investigated. This study aimed to investigate gene-environment interactions among moderate/severe periodontitis, polymorphisms of adiponectin (ADIPOQ)-rs1501299, and leptin receptor (LEPR)-rs1137100 on T2DM risk in Chinese subjects. DESIGN: A case-control study was conducted in 239 Chinese participants from Beijing Hypertension Association Institute (BHAL). After full-mouth periodontal examinations, the participants underwent bilateral buccal swabs for DNA testing. ADIPOQ-rs1501299 and LEPR-rs1137100 were used for genotyping. Generalised multifactor dimensionality reduction (GMDR) and logistic regression were used to examine the interactions among single nucleotide polymorphisms (SNPs) and moderate/severe periodontitis on the risk of T2DM. RESULTS: The risk of T2DM was higher in moderate/severe periodontitis [adjusted odds ratio (AOR) = 3.67, 95% confidence interval (95%CI): 1.26-10.71] in ADIPOQ-rs1501299 GG genotype (AOR = 3.42, 95%CI: 1.81-6.46) and LEPR-rs1137100 GG genotype (AOR = 3.16, 95%CI: 1.56-6.39). The GMDR model indicated that there was a significant three-factor model (p = 0.001) involving rs1501299, rs1137100, and moderate/severe periodontitis, demonstrating a potential gene-environment interaction among periodontitis, polymorphisms of rs1501299, and rs1137100 influencing the risk of T2DM. Moderate/severe periodontitis patients with rs1501299-GG and rs1137100-GG have the highest T2DM risk after adjusting for age, gender, BMI, WHR, smoking status, alcohol consumption, economic status, and hypertension (AOR = 20.39, 95%CI: 2.64-157.26). CONCLUSIONS: Interactions among moderate/severe periodontitis, rs1501299-GG, and rs1137100-GG were associated with an increased risk of T2DM. This study may provide a new insight into the effect of gene-environment interactions on T2DM.


Subject(s)
Adiponectin/genetics , Diabetes Mellitus, Type 2/genetics , Gene-Environment Interaction , Periodontitis/epidemiology , Periodontitis/genetics , Receptors, Leptin/genetics , Asian People , Case-Control Studies , Genetic Predisposition to Disease , Genotype , Humans , Polymorphism, Single Nucleotide , Risk Factors
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