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1.
Nano Lett ; 24(22): 6761-6766, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38775803

RESUMO

Orbital angular momentum (OAM) multiplexed holograms have attracted a great deal of attention recently due to their physically unbounded set of orthogonal helical modes. However, preserving the OAM property in each pixel hinders fine sampling of the target image in principle and requires a fundamental filtering aperture array in the detector plane. Here, we demonstrate the concept of metasurface-based vectorial holography with cylindrical vector beams (CVBs), whose unlimited polarization orders and unique polarization distributions can be used to boost information storage capacity. Although CVBs are composed of OAM modes, the holographic images do not preserve the OAM modes in our design, enabling fine sampling of the target image in a quasi-continuous way like traditional computer-generated holograms. Moreover, the images can be directly observed by passing them through a polarizer without the need for a fundamental mode filter array. We anticipate that our method may pave the way for high-capacity holographic devices.

2.
Opt Lett ; 49(10): 2573-2576, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748108

RESUMO

We propose a new, to the best of our knowledge, type of metalens of which the phase profile is extracted from the higher-order Bessel function. A light beam passing through this metalens would focus along the circular trajectory and produces a tightly focusing field. Utilizing phase binarization, we provide a method to design the geometric-phase dielectric metasurface both for phase and polarization modulations. We demonstrate two metalenses for circularly and radially polarized output beams at 633 nm, with the measured 0.737λ and 0.616λ focal spots, respectively. Theoretically, it can realize a super-diffraction-limit spot (0.38λ). This work can extend the way of realizing tightly focused optical devices.

3.
Appl Opt ; 63(3): 668-675, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38294378

RESUMO

Hollow corner-cube retroreflectors (HCCRs) are an essential reflection component of next-generation lunar laser-ranging technology. The verticality among the three reflectors, known as the right-angle error, is a critical parameter that affects the emission performance, and thus, should be correctly measured and calibrated. However, conventional methods measure the three right-angle errors separately, which can induce error superposition during the measurement process. A one-time measurement method was developed for the three right-angle errors of the HCCR using a single autocollimator (AC). The method establishes a mathematical relationship between the right-angle error of the HCCR and the angle offset of the reflected beam, and it considers the observation coordinates of the AC simultaneously to perform the coordinate transformation of the relationship parameters. The corresponding measurement equation was derived to extract the three-plane right-angle error of the HCCR using the measured readings of a single AC. In addition, a HCCR was designed to freely adjust the angle of the two reflective surfaces and used to simulate the different states of the three right-angle errors in practice. The measurement results show that the root-mean-square error of the proposed method in all right-angle error states is smaller than 16 ' ' .

4.
Opt Express ; 31(2): 2061-2071, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785228

RESUMO

The remarkable advances in nanofabrication that have occurred over the last decade present opportunities for the realization of new types of holograms. In this work, for the first time to the best of our knowledge, a method for phase multicolor holograms based on nanohole arrays is described. The nanoholes are in an aluminum film that is interposed between the glass substrate and a silicon dioxide layer. The nanoholes serve as color filters for blue, green, and red wavelengths and provide the necessary phase distribution via the detour phase method. Our nanohole arrays are optimized to maximize the transmission efficiency of the red, green, and blue channels and to minimize the cross-talk between them. We design two multicolor holograms based on these filters and simulate their performance. The results show good fidelity to the desired holographic images. The proposed structure has the advantages of being very compact, of requiring only a simple fabrication method with one lithography step, and of employing materials (aluminum and silicon dioxide) that are compatible with standard CMOS technology.

5.
Opt Lett ; 48(16): 4217-4220, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37581996

RESUMO

Metasurface-based vectorial holography can reconstruct images with different polarization states. However, the number of polarization channels in the holographic image is relatively small in traditional methods. Here, we propose and demonstrate a metasurface vectorial hologram which carries infinite polarization channels. It can independently control the holographic pattern and polarization distribution, which can be regarded as two independent storage dimensions. We use a supercell-based metasurface to independently control the complex amplitude of the left-handed circularly polarized and right-handed circularly polarized components of the transmitted light, which then superpose in the observation plane for the vectorial pattern generation. Different from most methods, our approach does not involve complex calculations, and it is suitable for far-field design. We anticipate that it may open avenues for future applications which require arbitrary intensity and polarization control.

6.
Int J Clin Pharmacol Ther ; 61(3): 129-138, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36458443

RESUMO

OBJECTIVE: To evaluate the pharmacokinetics (PK), safety, and bioequivalence of two formulations of apixaban in healthy Chinese subjects under fasting and fed conditions. MATERIALS AND METHODS: A single-center, randomized, open, single-dose, two-period crossover PK study was carried out under fasting and fed conditions in 64 healthy subjects enrolled in either the fasting (36 subjects) or the fed (28 subjects) arms of the study. Subjects received a single oral dose of 2.5 mg apixaban tablets as test (T) or reference (R) formulation. The primary PK parameters determined were the area under the plasma concentration-time curve from zero to t and ∞ (AUC0-t and AUC0-∞) and the maximal plasma concentration (Cmax). Safety was assessed mainly from the occurrence of adverse events (AEs). RESULTS: A single drop-out in the fed arm of the trial was excluded from the statistical evaluation. The 90% confidence intervals (CIs) for the geometric mean ratio (GMR) for T/R using AUC0-t were 95.4 - 100.9% and 97.8 - 103.8%, and for AUC0-∞ were 95.3 - 100.6% and 98.3 - 104.3% under fasting (36 subjects) and fed (27 subjects) conditions, respectively. Similarly, the 90% CIs for Cmax were 94.6 - 103.1% and 88.8 - 102.0% under fasting (36 subjects) and the fed (27 subjects) conditions, respectively. Therefore, the 90% CIs for the T/R AUC and Cmax ratios were within the standard range for bioequivalence (80.0 - 125.0%). There were no serious adverse events (SAEs). CONCLUSION: The test and reference 2.5 mg apixaban tablets were bioequivalent and both showed good tolerability and safety.


Assuntos
População do Leste Asiático , Pirazóis , Piridonas , Equivalência Terapêutica , Humanos , Área Sob a Curva , Estudos Cross-Over , Jejum , Voluntários Saudáveis , Comprimidos , Pirazóis/farmacocinética , Piridonas/farmacocinética
7.
J Neurosci Res ; 100(6): 1257-1280, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35293012

RESUMO

Alzheimer's disease (AD), an age-related neurodegenerative disease, is a striking global health problem. Ferroptosis is a newly discovered form of cell death characterized by iron-dependent lipid peroxidation products and the accumulation of lethal reactive oxygen species. Strict regulation of iron metabolism is essential to ensure neuronal homeostasis. Excess and deficiency of iron are both associated with neurodegeneration. Studies have shown that oxidative stress caused by cerebral iron metabolism disorders in the body is involved in the process of AD, ferroptosis may play an important role in the pathogenesis of AD, and regulating ferroptosis is expected to be a new direction for the treatment of AD. Various organelles are closely related to ferroptosis: mitochondria, endoplasmic reticulum, Golgi apparatus, and lysosome are involved in the regulation of ferroptosis from the aspects of iron metabolism and redox imbalance. In this review, the relationship between AD and the dysfunction of organelles (including mitochondria, endoplasmic reticulum, lysosome, and Golgi apparatus) and the role of organelles in ferroptosis of AD were reviewed to provide insights for understanding the relationship between organelles and ferroptosis in AD and the treatment of AD.


Assuntos
Doença de Alzheimer , Ferroptose , Doenças Neurodegenerativas , Doença de Alzheimer/metabolismo , Humanos , Ferro/metabolismo , Peroxidação de Lipídeos , Mitocôndrias/metabolismo , Doenças Neurodegenerativas/patologia , Espécies Reativas de Oxigênio/metabolismo
8.
Opt Express ; 30(10): 16134-16144, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221464

RESUMO

Slow wave and localized field are conducive to terahertz (THz) modulators with deep and fast modulation. Here we propose an electrically controlled THz modulator with slow wave effect and localized field composed of a high electron mobility transistor (HEMT) integrated metasurface. Unlike previously proposed schemes to realize slow wave effect electrically, this proposal controls the resonant modes directly through HEMT switches instead of the surrounding materials, leading to a modulation depth of 96% and a group delay of 10.4ps. The confined electric field where HEMT is embedded, and the slow wave effect, work together to pave a new mechanism for THz modulators with high performance.

9.
Opt Lett ; 47(10): 2490-2493, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35561383

RESUMO

Mid-infrared (MIR) spectroscopy has numerous industrial applications and is usually performed with Fourier-transform infrared (FTIR) spectrometers. While these work well for many purposes, there is currently much interest in alternative approaches that are smaller and lighter, i.e., MIR microspectrometers. Here we investigate all-dielectric metasurfaces as spectral filters for MIR microspectrometers. Two metasurface types are studied. For the first, we design, fabricate, and test a metasurface with a narrow and angularly tunable transmission stop band. We use it to reconstruct the transmission spectra of various materials. The second metasurface, investigated theoretically, possesses narrow passband features via symmetry-protected bound states in the continuum.

10.
Opt Lett ; 47(2): 353-356, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35030604

RESUMO

Achieving arbitrary manipulation of the fundamental properties of a light wave with a metasurface is highly desirable and has been extensively developed in recent years. However, common approaches are typically targeted to manipulate only one dimension of light wave (amplitude, phase, or polarization), which is not quite sufficient for the acquisition of integrated multifunctional devices. Here, we propose a strategy to design single-layer dielectric metasurfaces that can achieve multidimensional modulation of a light wave. The critical point of this strategy is spin-decoupled complex amplitude modulation, which is realized by combining propagation and geometric phases with polarization-dependent interference. As proofs of concept, perfect vector vortex beams and polarization-switchable stereoscopic holographic scenes are experimentally demonstrated to exhibit the capability of multidimensional light wave manipulation, which unlocks a flexible approach for the multidimensional manipulation of a light wave such as complex light-wave control and vectorial holography in integrated optics and polarization-oriented applications.

11.
Nano Lett ; 21(4): 1735-1741, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33544611

RESUMO

Metasurface-based holography presents opportunities for applications that include optical displays, data storage, and optical encryption. Holograms that control polarization are sometimes referred to as vectorial holograms. Most studies on this topic have concerned devices that display different images when illuminated with different polarization states. Fewer studies have demonstrated holographic images whose polarization varies spatially, i.e., as a function of the position within the image. Here, we experimentally demonstrate a vectorial hologram that produces an image with a spatially continuous distribution of polarization states, for the first time to our knowledge. An unlimited number of polarization states can be achieved within the image. Furthermore, the holographic image and its polarization map (polarization vs position in image) are independent. The same image can be thus encoded with different polarization maps. As far as we know, our approach is conceptually new. We anticipate that it could broaden the application scope of metasurface holography.

12.
Int J Mol Sci ; 23(24)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36555632

RESUMO

Flexible polymer-based magnetoelectric (ME) materials have broad application prospects and are considered as a new research field. In this article, FeCoSiB thin films were deposited on poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE) substrate by DC magnetron sputtering. The structure of PVDF-TrFE/FeCoSiB heterostructure thin films was similar to 2-2. Under a bias magnetic field of 70 Oe, the composites have a dramatically increased ME voltage coefficient as high as 111 V/cm⋅Oe at a frequency of about 85 kHz. The piezoelectric coefficient of PVDF-TrFE thin films is 34.87 pC/N. The surface morphology of PVDF-TrFE thin films were studied by FESEM, and the results of XRD and FTIR showed that the ß-phase of PVDF-TrFE thin films was dominant. Meanwhile, the effects of different heating conditions on the crystallization and piezoelectric properties of PVDF-TrFE films were also studied. The flexible ME heterojunction composite has a significant ME voltage coefficient and excellent piezoelectric properties at room temperature, which allows it to be a candidate material for developing flexible magnetoelectric devices.


Assuntos
Polímeros de Fluorcarboneto , Calefação , Cristalização
13.
Molecules ; 26(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34443634

RESUMO

Microwave-absorbing materials have attracted increased research interest in recent years because of their core roles in the fields of electromagnetic (EM) pollution precaution and information security. In this paper, microwave-absorbing material NiFe-layered double hydroxide (NiFe-LDH) was synthesized by a simple co-precipitation method and calcined for the fabrication of NiFe-mixed metal oxide (NiFe-MMO). The phase structure and micromorphology of the NiFe-LDH and NiFe-MMO were analyzed, and their microwave-absorbing properties were investigated with a vector network analyzer in 2-18 GHz. Both NiFe-LDH and NiFe-MMO possessed abundant interfaces and a low dielectric constant, which were beneficial to electromagnetic wave absorption, owing to the synergistic effect of multi-relaxation and impedance matching. The optimum reflection loss (RL) of NiFe-LDH and NiFe-MMO was -58.8 dB and -64.4 dB, respectively, with the thickness of 4.0 mm in the C band. This work demonstrates that LDH-based materials have a potential application in electromagnetic wave absorption.

14.
Opt Express ; 23(8): 10272-81, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25969069

RESUMO

The miniaturization of measurement systems currently used to characterize the polarization state of light is limited by the bulky optical components used such as polarizers and waveplates. We propose and experimentally demonstrate a simple and compact approach to measure the ellipticity and handedness of the polarized light using an ultrathin (40 nm) gradient metasurface. A completely polarized light beam is decomposed into a left circularly polarized beam and a right circularly polarized beam, which are steered in two directions by the metasurface consisting of nanorods with spatially varying orientations. By measuring the intensities of the refracted light spots, the ellipticity and handedness of various incident polarization states are characterized at a range of wavelengths and used to determine the polarization information of the incident beam. To fully characterize the polarization state of light, an extra polarizer can be used to measure the polarization azimuth angle of the incident light.

15.
Zhongguo Dang Dai Er Ke Za Zhi ; 15(11): 979-82, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24229593

RESUMO

OBJECTIVE: To study the prevalence, epidemiological characteristics, and risk factors for childhood asthma in Yichang City, China and to collect evidence for the early diagnosis and preventive treatment of asthma. METHODS: Preliminary screening questionnaires were distributed to more than 90% of children in 5 kindergartens, 10 primary and secondary schools, and 5 communities in Yichang City to detect children with suspected asthma. These surveyed children were selected by cluster random sampling. A further questionnaire survey was conducted for suspected cases. Meanwhile, a similar number of sex- and age-matched non-asthmatic children were selected for the case-control study. Information from returned questionnaires was entered into a database for statistical analysis. RESULTS: A total of 11 000 questionnaires were distributed, and 10 456 (95.1%) questionnaires were returned. The prevalence rate of asthma among children in Yichang was 3.47%, significantly higher in boys than in girls (P<0.05). A total of 107 out of 363 children with asthma had a history of drug allergy, and 152 cases had a family history of allergy. The majority of asthmatic children had irregular onset-prone seasons and hours. Respiratory tract infections were the most common trigger of asthma attacks, accounting for 93.1% of all onsets; family history of allergy, history of early use of antibiotics, history of housing renovation, and history of passive smoking were the major risk factors for asthma. CONCLUSIONS: Prevention of respiratory tract infections may reduce the frequency of asthma attacks; reducing the use of antibiotics during early childhood, decreasing the frequency of housing renovation, and advocating for smoking cessation among parents have preventive effects on asthma.


Assuntos
Asma/epidemiologia , Adolescente , Asma/etiologia , Asma/prevenção & controle , Índice de Massa Corporal , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prevalência , Infecções Respiratórias/complicações , Fatores de Risco , Inquéritos e Questionários
16.
Clin Pharmacol Drug Dev ; 12(3): 273-278, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36047047

RESUMO

The purpose of this trial was to evaluate the pharmacokinetics (PK), bioequivalence (BE), and safety of 2 preparations of hydroxychloroquine (200-mg tablet) under fasting and fed conditions. A total of 180 subjects (fasting condition: n = 80; fed condition: n = 100) were randomly enrolled in this randomized, open, single-dose, single-cycle parallel phase Ⅰ clinical study. Under the 2 conditions, the subjects were randomly administered the test (T) or reference (R) tablet, both at a dose of 200 mg (1 tablet). Liquid chromatography-tandem mass spectrometry was used to determine the concentration of hydroxychloroquine in healthy subjects after oral administration of the T or R preparation to evaluate the PK characteristics. In this trial, the T and R preparations of hydroxychloroquine were bioequivalent under both conditions within the range of 80%-125%. No serious adverse events (SAEs) were found in the safety assessments for either condition, and all adverse events (AEs) were mild, except for 2 moderate AEs in the fed condition, indicating good safety.


Assuntos
Hidroxicloroquina , Equivalência Terapêutica , Humanos , Área Sob a Curva , População do Leste Asiático , Jejum , Voluntários Saudáveis , Hidroxicloroquina/farmacocinética , Comprimidos
17.
Nat Commun ; 13(1): 6687, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335215

RESUMO

Optical cryptography manifests itself a powerful platform for information security, which involves encrypting secret images into visual patterns. Recently, encryption schemes demonstrated on metasurface platform have revolutionized optical cryptography, as the versatile design concept allows for unrestrained creativity. Despite rapid progresses, most efforts focus on the functionalities of cryptography rather than addressing performance issues, such as deep security, information capacity, and reconstruction quality. Here, we develop an optical encryption scheme by integrating visual cryptography with metasurface-assisted pattern masking, referred to as Stokes meta-hologram. Based on spatially structured polarization pattern masking, Stokes meta-hologram allows multichannel vectorial encryption to mask multiple secret images into unrecognizable visual patterns, and retrieve them following Stokes vector analysis. Further, an asymmetric encryption scheme based on Stokes vector rotation transformation is proposed to settle the inherent problem of the need to share the key in symmetric encryption. Our results show that Stokes meta-hologram can achieve optical cryptography with effectively improved security, and thereby paves a promising pathway toward optical and quantum security, optical communications, and anticounterfeiting.

18.
Burns Trauma ; 10: tkac009, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35265724

RESUMO

Background: Circular RNA (circRNA) plays key regulatory roles in the development of many diseases. However the biological functions and potential molecular mechanisms of circRNA in the injury and repair of intestinal mucosa in mice after severe burns are yet to be elucidated. Methods: Cell counting kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), wound healing and transwell assays were used to detect cell proliferation and migration ability. Real-time quantitative PCR was used to identify the expression of circRNA, microRNA and messenger RNA. Nuclear and cytoplasmic separation experiments were employed to perceive the location of circRNA_Maml2. Finally, in vitro and in vivo experiments were conducted to study the repairing effect of circRNA_Maml2 on the intestinal mucosa of mice after severe burns. Results: When compared with the control group, the expression of circRNA_Maml2 was significantly reduced in the severe burn group. Furthermore, overexpression of circRNA_Maml2 promoted the proliferation and migration of CT26.wt cells in vivo and the repair of damaged intestinal mucosa in vitro. CircRNA_Maml2 acted as a sponge adsorption molecule for miR-93-3p to enhance the expression of frizzled class receptor 7 and activate the downstream Wnt/ß-catenin pathway, thereby promoting the repair of the intestinal mucosa. Conclusions: Our findings demonstrate that circRNA_Maml2 regulates the miR-93-3p/FZD7/Wnt/ß-catenin pathway and promotes the repair of damaged intestinal mucosa. Hence, circRNA_Maml2 is a potential therapeutic target to promote intestinal mucosal repair.

19.
Adv Mater ; 34(3): e2103192, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34363242

RESUMO

Metasurfaces provide a compact and powerful platform for manipulating the fundamental properties of light, and have shown unprecedented capabilities in both optical holographic display and information encryption. For increasing information display/storage capacity, metasurfaces with more polarization manipulation channel and full-color holographic functionality are now an urgent requirement. Here, a minimalist dielectric metasurface with the capability of full-color holography encoded with arbitrary polarization is proposed and experimentally demonstrated. Without the daunting exploratory and computational problem in nanostructure searching, full-color holographic images can be multiplexed into arbitrary polarization channels through vectorial ptychography and k-space ptychography based on tetratomic macropixel geometric phase metasurfaces. Thanks to the full degree of freedom tuning in polarization and color spaces, the application scenarios such as holographic 3D imaging and information encryption are realized. The strategy exhibits promising potential in applications of 3Dl display, augmented/virtual reality, high-density data storage, and encryption.

20.
Oncol Lett ; 23(1): 8, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34820007

RESUMO

Isoliensinine is a bis-benzylisoquinoline alkaloid that can be isolated from the lotus Nelumbo nucifera Gaertn. It has been reported to exert a variety of anti-cancer properties. In the present study, the potential effects of isoliensinine on cervical cancer Siha, HeLa, Caski and C33A cell lines were investigated by using Cell Counting Kit-8 (CCK-8), flow cytometry, western blotting and reverse transcription-PCR (RT-PCR) to measure cell proliferation, the cell cycle and apoptosis, in addition to elucidating the underlying molecular mechanism. Protein levels of p21, CDK2, Cyclin E, Mcl-1, cleaved Caspase-9, AKT, phosphorylated-AKT, glycogen synthase kinase (Gsk)3α, PTEN, and mRNA levels of p21, p15, p27, CDK2, CDK4, Cyclin E, Cyclin D, Gsk3α, Gsk3ß and PTEN were measured. Molecular docking assays were used to calculate the strength of binding of isoliensinine to AKT using AutoDock 4.0. Isoliensinine was found to induce cell cycle arrest at the G0/G1 phase by upregulating p21 expression and downregulating CDK2 and cyclin E in breast cancer cells. In addition, in previous research, isoliensinine promoted cell apoptosis by downregulating myeloid-cell leukemia 1 expression and activating caspase-9. Upstream, isoliensinine significantly downregulated AKT (S473) phosphorylation and GSK3α expression in a dose- and time-dependent manner. The AKT inhibitor AKTi-1/2 enhanced the function of isoliensinine on cell cycle arrest and apoptosis through the AKT/GSK3α pathway. AutoDock analysis showed that isoliensinine can bind to the AKT protein. These findings suggest that isoliensinine can induce cervical cancer cell cycle arrest and apoptosis by inhibiting the AKT/GSK3α pathway, which represents a novel strategy for the treatment of cervical cancer.

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