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1.
J Biol Chem ; 300(3): 105721, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311175

RESUMO

Histone H3 tyrosine-99 sulfation (H3Y99sulf) is a recently identified histone mark that can cross-talk with H4R3me2a to regulate gene transcription, but its role in cancer biology is less studied. Here, we report that H3Y99sulf is a cancer-associated histone mark that can mediate hepatocellular carcinoma (HCC) cells responding to hypoxia. Hypoxia-stimulated SNAIL pathway elevates the expression of PAPSS2, which serves as a source of adenosine 3'-phosphate 5'-phos-phosulfate for histone sulfation and results in upregulation of H3Y99sulf. The transcription factor TDRD3 is the downstream effector of H3Y99sulf-H4R3me2a axis in HCC. It reads and co-localizes with the H3Y99sulf-H4R3me2a dual mark in the promoter regions of HIF1A and PDK1 to regulate gene transcription. Depletion of SULT1B1 can effectively reduce the occurrence of H3Y99sulf-H4R3me2a-TDRD3 axis in gene promoter regions and lead to downregulation of targeted gene transcription. Hypoxia-inducible factor 1-alpha and PDK1 are master regulators for hypoxic responses and cancer metabolism. Disruption of the H3Y99sulf-H4R3me2a-TDRD3 axis can inhibit the expression and functions of hypoxia-inducible factor 1-alpha and PDK1, resulting in suppressed proliferation, tumor growth, and survival of HCC cells suffering hypoxia stress. The present study extends the regulatory and functional mechanisms of H3Y99sulf and improves our understanding of its role in cancer biology.


Assuntos
Carcinoma Hepatocelular , Histonas , Neoplasias Hepáticas , Tirosina , Humanos , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Hipóxia/genética , Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Hepáticas/metabolismo , Tirosina/metabolismo
2.
Nat Chem Biol ; 19(7): 855-864, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36805701

RESUMO

Tyrosine sulfation is a common posttranslational modification in mammals. To date, it has been thought to be limited to secreted and transmembrane proteins, but little is known about tyrosine sulfation on nuclear proteins. Here we report that SULT1B1 is a histone sulfotransferase that can sulfate the tyrosine 99 residue of nascent histone H3 in cytosol. The sulfated histone H3 can be transported into the nucleus and majorly deposited in the promoter regions of genes in chromatin. While the H3Y99 residue is buried inside octameric nucleosome, dynamically regulated subnucleosomal structures provide chromatin-H3Y99sulf the opportunity of being recognized and bound by PRMT1, which deposits H4R3me2a in chromatin. Disruption of H3Y99sulf reduces PRMT1 binding to chromatin, H4R3me2a level and gene transcription. These findings reveal the mechanisms underlying H3Y99 sulfation and its cross-talk with H4R3me2a to regulate gene transcription. This study extends the spectrum of tyrosine sulfation on nuclear proteins and the repertoire of histone modifications regulating chromatin functions.


Assuntos
Histonas , Tirosina , Animais , Histonas/metabolismo , Tirosina/genética , Cromatina , Proteínas Nucleares/metabolismo , Transcrição Gênica , Mamíferos/genética
3.
Appl Opt ; 63(13): 3576-3584, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856543

RESUMO

Spectral imaging technology based on on-chip spectroscopy can find applications in areas including aerospace, industrial and consumer electronics, and so on. Since each application normally requires a different set and number of spectral bands, the development of customized spectroscopy solutions with more compact size and lower cost becomes quite important. In this paper, we demonstrate a compact, highly customizable imaging spectrometer scheme based on custom-made multi-strip filter arrays, which maintains an average high transmission of ∼85%, narrow bandwidth of ∼30n m, and high optical density of ∼O D2 in the blocking regions across the visible to near-infrared waveband. Spectral imaging experiments are conducted, and the accurate reconstruction of sparse spectral image data is demonstrated as well to prove the validity of the proposed scheme. As a result, the work reported in this paper allows researchers to develop customized spectral imaging equipment in a relatively easy way and also has a great potential to be engineered further for scalable production with a quite low cost.

4.
Appl Opt ; 63(8): 1995-2003, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38568640

RESUMO

For gravitational wave detection, the telescope is required to have an ultra-low wavefront error and ultra-high signal-to-noise ratio, where the power of the stray light should be controlled on the order of less than 10-10. In this work, we propose an alternative stray light suppression method for the optical design of an off-axis telescope with four mirrors by carefully considering the optimal optical paths. The method includes three steps. First, in the period of the optical design, the stray light caused by the tertiary mirror and the quaternary mirror is suppressed by increasing the angle formed by the optical axes of the tertiary mirror and the quaternary mirror and reducing the radius of curvature of the quaternary mirror as much as possible to make sure the optical system provides a beam quality with a wavefront error less than λ/80. Next, the stray light could satisfy the requirement of the order of 10-10 when the level of roughness reaches 0.2 nm, and the pollution of mirrors is controlled at the level of CL100. Finally, traditional stray light suppression methods should also be applied to mechanics, including the use of the optical barrier, baffle tube, and black paint. It can be seen that the field stop can efficiently reduce stray light caused by the secondary mirror by more than 55% in the full field of view. The baffle tube mounted on the position of the exit pupil can reduce the overall stray light energy by 5%, and the difference between the ideal absorber (absorption coefficient is 100%) and the actual black paint (absorption coefficient is 90%) is 3.2%. These simulation results are confirmed by the Monte Carlo method for a stray light analysis. Based on the above results, one can conclude that the geometry structure of the optical design, the quality of mirrors, and the light barrier can greatly improve the stray light suppression ability of the optical system, which is vital when developing a gravitational wave telescope with ultra-low stray light energy.

5.
Sensors (Basel) ; 24(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38475226

RESUMO

The remarkable light perception abilities of the mantis shrimp, which span a broad spectrum ranging from 300 nm to 720 nm and include the detection of polarized light, serve as the inspiration for our exploration. Drawing insights from the mantis shrimp's unique visual system, we propose the design of a multifunctional imaging sensor capable of concurrently detecting spectrum and polarization across a wide waveband. This sensor is able to show spectral imaging capability through the utilization of a 16-channel multi-waveband Fabry-Pérot (FP) resonator filter array. The design incorporates a composite thin film structure comprising metal and dielectric layers as the reflector of the resonant cavity. The resulting metal-dielectric composite film FP resonator extends the operating bandwidth to cover both visible and infrared regions, specifically spanning a broader range from 450 nm to 900 nm. Furthermore, within this operational bandwidth, the metal-dielectric composite film FP resonator demonstrates an average peak transmittance exceeding 60%, representing a notable improvement over the metallic resonator. Additionally, aluminum-based metallic grating arrays are incorporated beneath the FP filter array to capture polarization information. This innovative approach enables the simultaneous acquisition of spectrum and polarization information using a single sensor device. The outcomes of this research hold promise for advancing the development of high-performance, multifunctional optical sensors, thereby unlocking new possibilities in the field of optical information acquisition.

6.
Fish Physiol Biochem ; 49(5): 983-1003, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37670169

RESUMO

The neuropeptide B/W signaling system is composed of neuropeptide B (NPB), neuropeptide W (NPW), and two cognate receptors, NPBWR1 and NPBWR2, which are involved in diverse physiological processes, including the central regulation of neuroendocrine axes in vertebrates. The components of this signaling system are not well conserved during vertebrate evolution, implicating its functional diversity. The present study characterized the ricefield eel neuropeptide B/W system, generated a specific antiserum against the neuropeptide B/W receptor, and examined the potential roles of the system in the regulation of adenohypophysial functions. The ricefield eel genome contains npba, npbb, and npbwr2b but lacks the npw, npbwr1, and npbwr2a genes. The loss of npw and npbwr1 probably occurred at the base of ray-finned fish radiation and that of npbwr2a species specifically in ray-finned fish. Npba and npbb genes are produced through whole-genome duplication (WGD) in ray-finned fish. The ricefield eel npba was expressed in the brain and some peripheral tissues, while npbb was predominantly expressed in the brain. The ricefield eel npbwr2b was also expressed in the brain and in some peripheral tissues, such as the pituitary, gonad, heart, and eye. Immunoreactive Npbwr2b was shown to be localized to Lh and Fsh cells but not to Gh or Prl cells in the pituitary of ricefield eels. Npba upregulated the expression of fshb and cga but not lhb mRNA in pituitary fragments of ricefield eels cultured in vitro. The results of the present study suggest that the NPB system of ricefield eels may be involved in the neuroendocrine regulation of reproduction.


Assuntos
Enguias , Neuropeptídeos , Animais , Enguias/genética , Enguias/metabolismo , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Gonadotropinas/metabolismo , Receptores de Neuropeptídeos/genética
7.
Opt Express ; 30(20): 36985-36995, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36258617

RESUMO

The bionic curved compound-eye camera is a bionic-inspired multi-aperture camera, which can be designed to have an overlap on the field of view (FOV) in between adjacent ommatidia so that 3D measurement is possible. In this work, we demonstrate the 3D measurement with a working distance of up to 3.2 m by a curved compound-eye camera. In that there are hundreds of ommatidia in the compound-eye camera, traditional calibration boards with a fixed-pitch pattern arrays are not applicable. A batch calibration method based on the CALTag calibration board for the compound-eye camera was designed. Next, the 3D measurement principle was described and a 3D measurement algorithm for the compound-eye camera was developed. Finally, the 3D measurement experiment on objects placed at different distances and directions from the compound-eye camera was performed. The experimental results show that the working range for 3D measurement can cover the whole FOV of 98° and the working distance can be as long as 3.2 m. Moreover, a complete depth map was reconstructed from a raw image captured by the compound-eye camera and demonstrated as well. The 3D measurement capability of the compound-eye camera at long working distance in a large FOV demonstrated in this work has great potential applications in areas such as unmanned aerial vehicle (UAV) obstacle avoidance and robot navigation.


Assuntos
Algoritmos , Calibragem
8.
Opt Express ; 29(21): 33346-33356, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809148

RESUMO

In this work, we demonstrate a prototype of a biomimetic multispectral curved compound eye camera (BMCCEC). In comparison with traditional multispectral imaging systems, the BMCCEC developed in this work has the distinct features of multi-spectral imaging on multiple targets in real time in an ultra-large field of view (FOV), which can be attributed to its biomimetic curved compound eye structure as well as the multispectral cluster network. Specifically, the BMCCEC has a total of 104 multispectral ommatidia and a FOV of 98°×98°, which is able to realize 7-band multispectral imaging with center wavelengths of 500 nm, 560 nm, 600 nm, 650 nm, 700 nm, 750 nm and 800 nm and a spectral resolution of 10 nm. A prototype of BMCCEC was then manufactured and multispectral imaging experiments were performed based on it. As a result, the red edge feature of the spectrum of green plants has been successfully obtained and retrieved with a good accuracy.

9.
World J Urol ; 39(2): 501-510, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32277278

RESUMO

OBJECTIVE: The new clinical criteria termed SOFA and qSOFA were demonstrated to be more accurate than SIRS in screening patients at high risk of sepsis. We aim to evaluate the ability of SOFA, qSOFA and SIRS to predict septic shock after PCNL. PATIENTS AND METHODS: Consecutive patients undergoing PCNL were included to assess the performance of SOFA, qSOFA and SIRS in predicting septic shock, the AUC of ROC curve and decision curve analysis were used, and the optimal cutoff values and their achieving time were calculated. RESULTS: Of the 431 included patients, 12 (2.7%) cases developed septic shock. Compared with non-septic shock patients, patients with septic shock were more likely to be female, have positive history of urine culture and higher urine leukocyte count, and show increased postoperative serum creatinine, PCT and decreased leukocyte. The optimal cutoff of SOFA, qSOFA and SIRS was > 2, > 0 and > 1, respectively. All of the 12 patients with verified septic shock met SOFA and SIRS criteria, while only 11 cases met qSOFA criterion. SOFA had the identical highest sensitivity (100%) and greater specificity (87% vs. 81%) than SIRS. qSOFA had higher specificity (92%) than both SOFA and SIRS at the expense of lower sensitivity (92%). The AUC of SOFA (0.973) to predict septic shock was greater than that of qSOFA (0.928) and SIRS (0.935). When combined with SIRS, SOFA outperformed qSOFA for discrimination of septic shock (AUC 0.987 vs. 0.978). Decision curve analysis indicated SOFA was clearly superior to both qSOFA and SIRS with a higher net benefit and net reduction in intervention. The qSOFA achieved the best time-based predictive efficiency, with the shortest median time to meet its cutoff, followed by SOFA and SIRS. CONCLUSION: The performance of SOFA in predicting septic shock after PCNL was slightly greater than qSOFA and SIRS. The comprehensive application of various criteria is recommended to assist early detection of septic shock following PCNL.


Assuntos
Nefrolitotomia Percutânea , Escores de Disfunção Orgânica , Complicações Pós-Operatórias/epidemiologia , Choque Séptico/epidemiologia , Síndrome de Resposta Inflamatória Sistêmica/epidemiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
10.
Opt Express ; 28(18): 27181-27195, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32906974

RESUMO

Generalized composite aperiodic zone plates (GCAZPs) are proposed to generate clearer images at focal planes. The images can be produced by a target object at infinity based on a collimator. The proposed zone plate consists of the proposed radial zone plate (RZP), whose original radius is not zero, and the common aperiodic zone plate, which has the coincident first-order diffraction area and the same axial first-order diffraction intensity distribution. The GCAZPs are applicable for the other aperiodic zone plates. Moreover, the modulation transfer function curve of the GCAZP is basically above that of the corresponding common aperiodic zone plate. Compared with the common aperiodic zone plates, the GCAZPs have the foci with higher intensity and the images with higher contrast at the same focal planes. In addition, a GCAZP with an arbitrary size can be designed. The construction method of the GCAZP is illustrated in details. Furthermore, it has been also proved numerically and experimentally that the GCAZPs are used to generate the clearer images than the corresponding common aperiodic zone plates. The proposed zone plates are applicable to generate clear images and trap particles stably at multiple planes simultaneously.

11.
Opt Express ; 28(25): 37827-37843, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33379610

RESUMO

A modified single-focus fractal zone plate (MSFFZP) is proposed to generate a single main focus with many subsidiary foci or two equal-intensity main foci with many subsidiary foci. Widths of high-transmission zones, which have influence on the number of the high-order diffraction foci, such as the second-order focus and the fourth-order focus, can adjust first-order fractal focal intensities, but have no influence on first-order focal positions. Moreover, the MSFFZPs have the first-order foci or the first and second order foci only along the optic axis. It is proved numerically and experimentally that the MSFFZP can generate one or two colourful images with the low chromatic aberrations at the focal planes, and the MSFFZP beam has the self-reconstruction property. In addition, the MSFFZP produces a series of foci at the different focal planes along the optic axis in the simulations and experiments. The method of constructing the MSFFZP is illustrated. The proposed zone plate can be used to produce the multiple clear images, trap particles at the multiple planes simultaneously, and generate the images with the low chromatic aberration.

12.
Opt Express ; 28(20): 30048-30062, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33114890

RESUMO

The obstacle of imaging through multimode fibers (MMFs) is encountered due to the fact that the inherent mode dispersion and mode coupling lead the output of the MMF to be scattered and bring about image distortions. As a result, only noise-like speckle patterns can be formed on the distal end of the MMF. We propose a deep learning model exploited for computational imaging through an MMF, which contains an autoencoder (AE) for feature extraction and image reconstruction and self-normalizing neural networks (SNNs) sandwiched and employed for high-order feature representation. It was demonstrated both in simulations and in experiments that the proposed AE-SNN combined deep learning model could reconstruct image information from various binary amplitude-only targets going through a 5-meter-long MMF. Simulations indicate that our model works effectively even in the presence of system noise, and the experimental results prove that the method is valid for image reconstruction through the MMF. Enabled by the spatial variability and the self-normalizing properties, our model can be generalized to solve varieties of other computational imaging problems.

13.
Opt Express ; 28(7): 9216-9231, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32225533

RESUMO

In this work, we propose a new type of multispectral imaging system, named multispectral curved compound eye camera (MCCEC). The so called MCCEC consists of three subsystems, a curved micro-lens array integrated with selected narrow-band optical filters, an optical transformation subsystem, and the data processing unit with an image sensor. The novel MCCEC system can achieve multi-spectral imaging at an ultra-large field of view (FOV), and obtain information of multiple spectrum segments at real time. Moreover, the system has the advantages of small size, light weight, and high sensitivity in comparison with conventional multispectral cameras. In current work, we mainly focus on the optical design of the MCCEC based on the overlap of FOV between the neighboring clusters of ommatidia to achieve the multispectral imaging at an ultra-large FOV. The optical layout of the curved micro-lens array, narrow-band filter array and the optical relay system for image plane transformation are carefully designed and optimized. The whole size of the optical system is 93 mm × 42 mm × 42 mm. The simulation results show that a maximum FOV of about 120° can be achieved for seven-waveband multispectral imaging with center wavelengths of 480 nm, 550 nm, 591 nm, 676 nm, 704 nm, 740 nm, and 767 nm. The new designed MCCEC has a great potential as an airborne or satellite-born payload for real time remote sensing and thus paves a new way for the design of compact and light-weight spectral-imaging cameras with an ultra large FOV.

14.
Opt Express ; 28(3): 3000-3008, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32121976

RESUMO

We investigated the optical binding force in a plasmonic heterodimer structure consisting of two nano-disks. It is found that when illuminated by a tightly focused radially polarized beam (RPB), the plasmon modes of the two nano-disks are strongly hybridized, forming bonding/antibonding modes. An interesting observation of this setup is that the direction of the optical binding force can be controlled by changing the wavelength of illumination, the location of the dimer, the diameter of the nano-disks, and the dimer gap size. Further analysis yields that the inhomogeneous polarization state of RPB can be utilized to readily control the bonding type of plasmon modes and distribute the underlying local field confined in the gap (the periphery) of the dimer, leading to a positive (negative) optical binding force. Our findings provide a clear strategy to engineer optical binding forces via changes in device geometry and its illumination profile. Thus, we envision a significant role for our device in emerging nanophotonics structures.

15.
Opt Lett ; 45(24): 6863-6866, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33325915

RESUMO

In this Letter, we demonstrate the design and fabrication of a biomimetic curved compound-eye camera (BCCEC) with a high resolution for detecting distant moving objects purpose. In contrast to previously reported compound-eye cameras, our BCCEC has two distinct features. One is that the ommatidia of the compound eye are deployed on a curved surface which makes a large field of view (FOV) possible. The other is that each ommatidium has a relatively large optical entrance and long focal length so that a distant object can be imaged. To overcome the mismatch between the curved focal plane formed by the curved compound eye and the planar focal plane of the CMOS image sensor (CIS), an optical relay subsystem is introduced between the compound eye and the CIS. As a result, a BCCEC with 127 ommatidia in the compound eye is designed and fabricated to achieve a large FOV of up to 98∘×98∘. The experimental results show that objects with a size of 100 mm can be clearly resolved at a distance of 25 m. The capture of the motion trajectories of a moving object is also demonstrated, which makes it possible to detect and track the moving targets in a huge FOV for security surveillance purposes.

17.
Mol Carcinog ; 58(8): 1450-1464, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31026381

RESUMO

Gastric cancer is the second leading cause of cancer-related mortality and the fourth most common cancer globally. High intratumor heterogeneity of advanced gastric cancer poses great challenges to targeted therapy due to simultaneous activation of many redundant cancer-driving pathways. A central common signaling mechanism in cancer is proline-directed phosphorylation, which is further regulated by the unique proline isomerase Pin1. Pin1 inhibition exerts anticancer activity by blocking multiple cancer-driving pathways in some cancers, but its role in gastric cancer is not fully understood. Here we detected Pin1 protein expression in 1065 gastric cancer patients and paired normal tissues using immunohistochemistry and Western blot, and then examined the effects of Pin1 overexpression, and genetic and chemical Pin1 inhibition using Pin1 short hairpin RNA or small molecule inhibitor all-trans retinoic acid (ATRA) on tumorigenesis of human gastric cancer in vitro and in vivo, followed by biochemical analyses to elucidate Pin1 regulated oncogenic pathways. We found that Pin1 was significantly overexpressed in primary and metastasized tumors, with Pin1 overexpression being correlated with advanced stage and poor prognosis. Furthermore, whereas Pin1 overexpression promoted the transformed phenotype in immortalized and nontransformed human gastric cells, either genetic or chemical Pin1 inhibition in multiple human gastric cancer cells potently suppressed cell growth, G1/S transition and colony formation in vitro, as well as tumor growth in xenograft tumor models in vivo, which were further supported by downregulation of multiple key oncoproteins in PI3K/AKT and Wnt/ß-catenin signaling pathways. These results not only provide the first evidence for a critical role of Pin1 in the tumorigenesis of gastric cancer but also suggest that targeting Pin1 using ATRA or other inhibitors offers an effective new therapeutic approach for treating advanced gastric cancer.


Assuntos
Peptidilprolil Isomerase de Interação com NIMA/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/patologia , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Carcinogênese/genética , Carcinogênese/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Peptidilprolil Isomerase de Interação com NIMA/antagonistas & inibidores , Peptidilprolil Isomerase de Interação com NIMA/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Tretinoína/farmacologia , Via de Sinalização Wnt
18.
Opt Express ; 26(1): 402-418, 2018 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-29328317

RESUMO

This paper presents the device design and performance analysis of a novel design of planar optical cross-connect (OXC) using nematic liquid crystal (NLC) waveguides. It employs N × N switching matrix in cross-bar fabric. In each unit cell, the input light is set in either the transverse electric (TE) mode or the transverse magnetic (TM) mode by electrically reorienting the NLC in the waveguide. The light then enters a passive waveguide and is routed to different paths depending on the polarization state (TE/TM mode). A sample device of 8 × 8 OXC is analyzed for performance estimation, which predicts a maximum on-chip insertion loss of 3 dB, an average cross-talk of -40 dB, ~1 ms switching time, and 2 mm × 2 mm footprint. The proposed OXC is unique in the switching mechanism of polarization-dependent routing and allows non-blocking switching with high compactness and broad bandwidth. It is potential for optical circuit switching in data centers and optical communication networks.

19.
Opt Express ; 26(6): 6532-6541, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29609341

RESUMO

This paper reports a tunable in-plane optofluidic lens by continuously tuning a silicone oil-air interface from concave to convex using the dielectrophoresis (DEP) force. Two parallel glasses are bonded firmly on two sides by NOA 81(Norland Optical Adhesive 81) spacers, forming an open microfluidic channel. An ITO (indium tin oxide) strip and another unpatterned ITO layer are deposited on two glasses as the top and bottom electrodes. Initially, a capillary concave liquid-air interface is formed at the end of the open channel. Then the DEP force is enabled to continuously deform the interface (lens) from concave to convex. In the experiment, the focal length gradually decreases from about -1 mm to infinite and then from infinite to around + 1 mm when the driving voltage is increased from 0 V to 260 V. Particularly, the longitudinal spherical aberration (LSA) is effectively suppressed to have LSA < 0.04 when the lens is operated in the focusing state. This work is the first study of in-plane tunable lenses using the DEP force and possesses special merits as compared to the other reported tunable lenses that are formed by pumping different liquids or by temperature gradient, such as wide tunability, no need for continuous supply of liquids, low power consumption (~81 nJ per switching) due to the capacitor-type driving, and the use of only one type of liquid. Besides, its low aberration makes it favorable for light manipulation in microfluidic networks.

20.
Opt Express ; 25(4): 3863-3874, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28241597

RESUMO

Biological research requires dynamic and wide-field optical microscopy with resolution down to nanometer to study the biological process in a sub-cell or single molecular level. To address this issue, we propose a dynamic wide-field optical nanoimaging method based on a meta-nanocavity platform (MNCP) model which can be incorporated in micro/nano-fluidic systems so that the samples to be observed can be confined in a nano-scale space for the ease of imaging. It is found that this platform can support standing wave surface plasmons (SW-SPs) interference pattern with a period of 105 nm for a 532 nm incident wavelength. Furthermore, the potential application of the NCP for wide-field super-resolution imaging was discussed and the simulation results show that an imaging resolution of sub-80 nm can be achieved.

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