Large viewing angle integral imaging 3D display system based on a symmetrical compound lens array.

We propose a large viewing angle integral imaging 3D display system based on a symmetrical compound lens array (SCLA). The display system comprises a high-resolution 2D display panel, an SCLA, and a light shaping diffuser. The high-resolution 2D display panel presents an elemental image array, the SCLA modulates the light rays emitted from the 2D display panel to form 3D images in space, and the light shaping diffuser eliminates the gaps between 3D pixels of the 3D images. We find that the lateral aberration is a crucial factor that affects the resolution of the reconstructed 3D image. The symmetrical structure of the SCLA enables a reduced focal length and the elimination of lateral aberration, improving the viewing angle and the 3D image resolution simultaneously. The experimental results confirm that the proposed display system increases the viewing angle to 68.6°, achieving a comparable resolution of the full field of view while maintaining a simple structure.

SIPA1 promotes angiogenesis by regulating VEGF secretion in Müller cells through STAT3 activation.

Diabetic retinopathy (DR) is a prevalent complication of diabetes that can lead to vision loss. The chronic hyperglycemia associated with DR results in damage to the retinal microvasculature. Müller cells, as a kind of macroglia, play a crucial role in regulating the retinal vascular microenvironment. The objective of this study was to investigate the role of signal-induced proliferation-associated protein 1 (SIPA1) in regulating angiogenesis in Müller cells. Through proteomics, database analysis, endothelial cell function tests, and Western blot detection, we observed an up-regulation of SIPA1 expression in Müller cells upon high glucose stimulation. SIPA1 expression contributed to VEGF secretion in Müller cells and regulated the mobility of retinal vascular endothelial cells. Further investigation of the dependence of SIPA1 on VEGF secretion revealed that SIPA1 activated the phosphorylation STAT3, leading to its translocation into the nucleus. Overexpression of SIPA1 combined with the STAT3 inhibitor STATTIC demonstrated the regulation of SIPA1 in VEGF expression, dependent on STAT3 activation. These findings suggest that SIPA1 promotes the secretion of pro-angiogenic factors in Müller cells by activating the STAT3 signaling pathway, thereby highlighting SIPA1 as a potential therapeutic target for DR.

Liquid lens based holographic camera for real 3D scene hologram acquisition using end-to-end physical model-driven network.

With the development of artificial intelligence, neural network provides unique opportunities for holography, such as high fidelity and dynamic calculation. How to obtain real 3D scene and generate high fidelity hologram in real time is an urgent problem. Here, we propose a liquid lens based holographic camera for real 3D scene hologram acquisition using an end-to-end physical model-driven network (EEPMD-Net). As the core component of the liquid camera, the first 10 mm large aperture electrowetting-based liquid lens is proposed by using specially fabricated solution. The design of the liquid camera ensures that the multi-layers of the real 3D scene can be obtained quickly and with great imaging performance. The EEPMD-Net takes the information of real 3D scene as the input, and uses two new structures of encoder and decoder networks to realize low-noise phase generation. By comparing the intensity information between the reconstructed image after depth fusion and the target scene, the composite loss function is constructed for phase optimization, and the high-fidelity training of hologram with true depth of the 3D scene is realized for the first time. The holographic camera achieves the high-fidelity and fast generation of the hologram of the real 3D scene, and the reconstructed experiment proves that the holographic image has the advantage of low noise. The proposed holographic camera is unique and can be used in 3D display, measurement, encryption and other fields.

Dual interface trapezium liquid prism with beam steering function.

In this paper, a dual interface trapezium liquid prism with beam steering function is implemented and analyzed. The electrowetting-on-dielectric method is used to perform the desired beam steering function without mechanical moving parts. This work examines deflection angles at different applied voltages to determine the beam steering range. The deflection angle can be experimentally measured from 0° to 3.43°. The proposed liquid prism can be applied in the field of optical manipulation, solar collecting system and so on.

On implications of somatostatin in diabetic retinopathy.

Somatostatin, a naturally produced neuroprotective peptide, depresses excitatory neurotransmission and exerts anti-proliferative and anti-inflammatory effects on the retina. In this review, we summarize the progress of somatostatin treatment of diabetic retinopathy through analysis of relevant studies published from February 2019 to February 2023 extracted from the PubMed and Google Scholar databases. Insufficient neuroprotection, which occurs as a consequence of declined expression or dysregulation of retinal somatostatin in the very early stages of diabetic retinopathy, triggers retinal neurovascular unit impairment and microvascular damage. Somatostatin replacement is a promising treatment for retinal neurodegeneration in diabetic retinopathy. Numerous pre-clinical and clinical trials of somatostatin analog treatment for early diabetic retinopathy have been initiated. In one such trial (EUROCONDOR), topical administration of somatostatin was found to exert neuroprotective effects in patients with pre-existing retinal neurodysfunction, but had no impact on the onset of diabetic retinopathy. Overall, we concluded that somatostatin restoration may be especially beneficial for the growing population of patients with early-stage retinopathy. In order to achieve early prevention of diabetic retinopathy initiation, and thereby salvage visual function before the appearance of moderate non-proliferative diabetic retinopathy, several issues need to be addressed. These include the needs to: a) update and standardize the retinal screening scheme to incorporate the detection of early neurodegeneration, b) identify patient subgroups who would benefit from somatostatin analog supplementation, c) elucidate the interactions of somatostatin, particularly exogenously-delivered somatostatin analogs, with other retinal peptides in the context of hyperglycemia, and d) design safe, feasible, low cost, and effective administration routes.

Color liquid crystal grating based color holographic 3D display system with large viewing angle.

Holographic 3D display is highly desirable for numerous applications ranging from medical treatments to military affairs. However, it is challenging to simultaneously achieve large viewing angle and high-fidelity color reconstruction due to the intractable constraints of existing technology. Here, we conceptually propose and experimentally demonstrate a simple and feasible pathway of using a well-designed color liquid crystal grating to overcome the inevitable chromatic aberration and enlarge the holographic viewing angle, thus enabling large-viewing-angle and color holographic 3D display. The use of color liquid crystal grating allows performing secondary diffraction modulation on red, green and blue reproduced images simultaneously and extending the viewing angle in the holographic 3D display system. In principle, a chromatic aberration-free hologram generation mechanism in combination with the color liquid crystal grating is proposed to pave the way for on such a superior holographic 3D display. The proposed system shows a color viewing angle of ~50.12°, which is about 7 times that of the traditional system with a single spatial light modulator. This work presents a paradigm for achieving desirable holographic 3D display, and is expected to provide a new way for the wide application of holographic display.

5-Bromo-3,4-dihydroxybenzaldehyde stabilizes diabetic retinal neurovascular units by inhibiting the inflammatory microenvironment.

BACKGROUND: Diabetic retinopathy (DR) is a leading cause of blindness characterized by damage to the retinal neurovascular unit, which is caused by hyperglycemia-induced metabolic and inflammatory responses. 5-Bromo-3,4-dihydroxybenzaldehyde (BDB) is a compound derived from marine red algae and known for its anti-inflammatory effects. METHODS: This study aimed to investigate the potential protective effects of BDB on DR using primary human retinal vascular endothelial cells and retinal tissue explants. The analysis involved assessing vascular integrity, expression of tight junction protein, hyperglycemia-induced permeability, and retinal ganglion cell (RGC) apoptosis. The protective effect of BDB in maintaining the diabetic retinal neurovascular units was verified using type 1 diabetic mouse models. Additionally, the inhibitory effect of BDB on the levels of inflammatory cytokines TNF-α, IL-1ß, and IL-6 were examined. RESULTS: In vitro experiments revealed that BDB promoted vascular integrity, inhibited the transcription of pro-inflammatory factors, and alleviated hyperglycemia-induced permeability. BDB also protected RGC from hyperglycemia-induced apoptosis. In diabetic mice models, BDB treatment maintained the integrity of diabetic retinal neurovascular units and inhibited the secretion of TNF-α, IL-1ß, and IL-6. CONCLUSION: BDB demonstrated a protective effect on DR by inhibiting the secretion of inflammatory factors, suggesting its potential as a therapeutic agent for the treatment of DR. Further research is warranted to validate its safety and efficacy for clinical application.

3D microscope image acquisition method based on zoom objective.

Microscopy is being pursued to obtain richer and more accurate information, and there are many challenges in imaging depth and display dimension. In this paper, we propose a three-dimensional (3D) microscope acquisition method based on a zoom objective. It enables 3D imaging of thick microscopic specimens with continuous adjustable optical magnification. The zoom objective based on liquid lenses can quickly adjust the focal length, to expand the imaging depth and change the magnification by adjusting the voltage. Based on the zoom objective, an arc shooting mount is designed to accurately rotate the objective to obtain the parallax information of the specimen and generate parallax synthesis images for 3D display. A 3D display screen is used to verify the acquisition results. The experimental results show that the obtained parallax synthesis images can accurately and efficiently restore the 3D characteristics of the specimen. The proposed method has promising applications in industrial detection, microbial observation, medical surgery, and so on.

Assessment and evaluation of Chitosan-Metamizole nanoparticles for the fracture healing and analgesic effect: Preclinical study in rat model.

To assess and evaluate Chitosan-Metamizole nanoparticles for fracture healing and analgesic potential, nanoparticles were formulated using the ionotropic gelation method. The nanoparticles were evaluated for particle size, zeta potential, polydispersity index, loading efficiency, surface characteristics and drug release properties. The analgesic activity was determined in carrageenan-induced arthritic male Wister rats. Further fracture healing potency, mechanical testing, radiographic examination and bone histology of the femur were studied. The drug loading efficiency of 11.38%-17.45%, particle size of 140-220 nm, and zeta potential of 19.12-23.14 mV were observed with a spherical, smooth appearance. Nanoparticles showed sustained release behaviour over a longer period. Nearly 4-fold inhibition of oedema was observed in animals treated with nanoparticles with excellent fracture healing potential. The femurs treated with nanoparticles required greater force to fracture. Nanoparticles significantly improved the strength and healing process. Histopathological studies showed the potential of nanoparticles in the healing process. The study confirmed the potential of nanoparticles in fracture healing and enhancement of analgesic activity.

Three-phase electrowetting liquid lens with deformable liquid iris.

Inspired by the arrangement of iris and crystalline lens in human eyes, we propose a three-phase electrowetting liquid lens with a deformable liquid iris (TELL-DLI). The proposed electrowetting liquid lens has three-phase fluid: air, conductive liquid, and dyed insulating liquid. The insulating liquid is distributed on the inner wall of the chamber in a ring shape. By applying voltage, the contact angle is changed, so that the dyed insulating liquid contracts towards the center, which is similar to the contraction of iris and the function of crystalline lens muscle in human eyes. The variation range of focal length is from -451.9 mm to -107.9 mm. The variation range of the aperture is from 4.89 mm to 0.6 mm. Under the step voltage of 200 V, the TELL-DLI can be switched between the maximum aperture state and the zero aperture state, and the switching time is ∼150/200 ms. Because of the discrete electrodes, TELL-DLI can regionally control the shape and position of the iris, and switch between circle, ellipse, sector, and strip. The TELL-DLI has a wide application prospect in imaging systems, such as microscopic imaging system, and has the potential to be applied in the field of complex beam navigation.

Depth of field and resolution-enhanced integral imaging display system.

Depth of field (DOF) and resolution are mutually restricted in integral imaging (II) display. To overcome the trade-offs, we propose an II display system that simultaneously enhances the DOF and resolution. The system consists of a transmissive mirror device (TMD), a semi-transparent mirror (STM), and two II display units. Each II display unit consists of a 4K display screen and a micro-lens array (MLA). Benefiting from the parallel placement of the TMD and the STM, two central depth planes are reconstructed, which effectively enhances the DOF. Meanwhile, the resolution in the overlapping DOF region is increased to two times due to the interpolation of the light field information from two II display units. The impact of the distance between the two II display units and the TMD on the 3D image quality is analyzed. In geometric optics, a distance between the II two display units and the TMD is optimized to eliminate ghost images. In wave optics, a distance is optimized to eliminate 3D pixel gaps by exploiting the diffraction effect of the TMD. Both the geometric and wave optics are considered simultaneously to obtain a high-quality 3D image without ghost images and 3D pixel gaps. A DOF and resolution-enhanced II display system is developed, and the experimental results verify its feasibility.

Method of color holographic display with speckle noise suppression.

In this paper, a method of color holographic display with speckle noise suppression is proposed. Firstly, the intensity information of the object is extracted according to the red, green and blue (RGB) channels. The band-limited phase is calculated and used as the initial phase for each color channel. Secondly, the double-step Fresnel diffraction algorithm is used to calculate the computer-generated holograms (CGHs), and a filter plane that dynamically adjusts the position of the filter in the optical path is designed. Then, a divergent spherical phase factor is added to the CGHs. Finally, the time average method is used to further reduce the speckle noise. When the CGHs of the RGB channels are loaded on the digital micromirror device and illuminated by the RGB lights emitting in a temporal sequence, the color reconstructed images with speckle noise suppression can be displayed. The validity of the proposed method is verified.

Real scene acquisition and holographic near-eye display system based on a zoom industrial endoscope.

In this paper, we propose a real scene acquisition and holographic near-eye display system based on a zoom industrial endoscope. By controlling the driving current of the liquid lens, the working distance and focal length of the zoom industrial endoscope can be tuned accordingly. Thus, the object at different depths can be captured. Then, the sub-sampling algorithm is used to generate the hologram. By adjusting the hologram sampling rate of the objects with different depths, the holographic near-eye 3D display can be realized. Experimental results demonstrate that the working distance of the zoom industrial endoscope can be tuned from 20 mm to 200 mm with the driving current changing from 80 mA to 190 mA. With the proposed system, the human eye can intuitively see the depth relationships among the real objects. The proposed system is expected to be applied to 3D display and industrial inspection fields.

Holographic near-eye display system with large viewing area based on liquid crystal axicon.

In this paper, a liquid crystal axicon based holographic near-eye display system with large viewing area is proposed. The viewing area of the system is extended by implementing the liquid crystal axicon. The error diffusion algorithm is used to calculate the computer-generated hologram (CGH). When incident on the liquid crystal axicon placed at the back focal plane of Fourier lens, the reconstruction light modulated by the CGH is deflected into two directions resulting in a viewing area extension. Meanwhile, to illustrate the potential of the proposed system, two-dimensional viewing area extension is demonstrated. It combines the frequency spectrum shift with the proposed system and achieves a double expansion of the horizontal viewing area and three-times expansion of the vertical viewing area. Feasibility of the proposed system is verified by optical experiments. The proposed system has potential applications in holographic augmented reality (AR) display.

5-Bromo-3,4-dihydroxybenzaldehyde attenuates endothelial cells injury from high glucose-induced damage.

Hyperglycemia triggers metabolic and inflammatory responses, which lead to vascular inflammation and consequently induce microvascular and/or macrovascular diabetic complications. 5-bromo-3,4-dihydroxybenzaldehyde (BDB), a marine red algae-derived bromophenol compound, is found to have diverse bioactivities, including the effect of anti-inflammation and anti-diabetes, though the mechanism of which is still unclear. To evaluate the anti-vasculopathy of BDB and explore the possible mechanism involved. Firstly, MTT assay was used to optimize the treatment concentration of glucose and BDB with HUVECs. Subsequently, we adopted two concentrations of BDB (50 µM and 100 µM) to verify the protective effect of BDB on vascular model, which was established by HUVECs from high glucose (30 mM)-induced damage. The cell migration and tube formation were used to evaluate the function of HUVECS. Moreover, the related mechanisms were analyzed by assays for flow cytometry, ELISA, qPCR, intracellular ROS and western blot. The present study demonstrated that BDB could protect endothelial cells from apoptosis caused by high glucose treatment. BDB also significantly reduced the secretion of inflammatory cytokines, such as TNF-α, IL-1ß and IL-6, induced by high glucose, which was also in agreement to the decrease of p65 protein expression and activities of NF-ĸB regulated by BDB. The reactive oxygen species (ROS) production and phosphorylation of 38 protein expression were also down-regulated by BDB compared to high glucose alone treatment. Furthermore, BDB reserved the endothelial cells functions of migration and tube formation under high glucose condition, which suggested that BDB could be a potential candidate in treating vascular inflammation induced by hyperglycemia.

System to eliminate the graininess of an integral imaging 3D display by using a transmissive mirror device.

We propose a system to eliminate the graininess of an integral imaging 3D display by using a transmissive mirror device (TMD). The proposed system consists of a 2D display, a micro-lens array (MLA), and a TMD. The TMD comprises square apertures with mirror-reflective inner wall. The light rays pass through the square aperture to form a diffraction spot, and the diffraction light intensity has a Sinc-function distribution. Therefore, the TMD can be used as an optical low-pass filter. In a certain imaging range, the mainlobe of the Sinc-function distribution is almost unchanged. The TMD has the property of a volumetric optical low-pass filter. It can interpolate the interval between discrete 3D pixels. Therefore, the TMD can be used to eliminate the graininess. The resolution of the 3D image is improved by 2.12 times. The experimental results verify the feasibility of the proposed system.

A latent profile analysis of residents' knowledge, attitude, and practice toward common chronic diseases among ethnic minority area in China.

Background: Health literacy plays an important role in preventing and managing chronic diseases, while low levels of health literacy among ethnic minorities are a major manifestation of health inequities. We believe that before effective health literacy intervention strategies, it is preferable to understand the features of health literacy among ethnic minorities. The present study firstly updated insights on health literacy among ethnic minorities by investigating the knowledge, attitude, and practice (KAP) profile of common chronic diseases in ethnic minority areas, and secondly discussed the KAP profiles in detail to inspire future health education interventions. Methods: A cross-sectional, health-literacy-sensitive study was conducted in China's typical ethnic minority area. Participants included 801 adult residents who lived in the ethnic minority area. The primary outcome was participant scores on the KAP questionnaire of common chronic diseases, followed by latent profile analysis to identify participants with similar KAP score patterns and determine whether membership in specific groups was associated with demographic or clinical characteristics. Results: The participants included 496 ethnic minorities (61.9%) and 305 Han Chinese (38.1%). Three-profile solution was determined after the latent profile analysis: incomplete transfer [I.T.] (n = 215), better practice [B.P.] (n = 301), and average [A.V.] (n = 285). IT group (26.84%) was characterized by the highest level of knowledge and attitude toward common chronic diseases and below average level for practice. Participants in B.P. group performed poorly in both knowledge and attitude toward common chronic diseases but had the highest level of practice. A.V. group reflected average knowledge, attitude, and practice toward common chronic diseases among three subgroups. Ethnic minorities were the dominant population in A.V. group (68.8%). Compared with other groups, the A.V. group contained the largest proportions of married participants (84.2%), participants with no formal education (46.7%), and high annual out-of-pocket medical expense (33.3%). Conclusion: A more specific and nuanced understanding of minority health literacy can enable service providers to provide more effective health education to their recipients, thereby improving health inequities.

Tunable liquid crystal grating based holographic 3D display system with wide viewing angle and large size.

As one of the most ideal display approaches, holographic 3-dimensional (3D) display has always been a research hotspot since the holographic images reproduced in such system are very similar to what humans see the actual environment. However, current holographic 3D displays suffer from critical bottlenecks of narrow viewing angle and small size. Here, we propose a tunable liquid crystal grating-based holographic 3D display system with wide viewing angle and large size. Our tunable liquid crystal grating, providing an adjustable period and the secondary diffraction of the reconstructed image, enables to simultaneously implement two different hologram generation methods in achieving wide viewing angle and enlarged size, respectively. By using the secondary diffraction mechanism of the tunable liquid crystal grating, the proposed system breaks through the limitations of narrow viewing angle and small size of holographic 3D display. The proposed system shows a viewing angle of 57.4°, which is nearly 7 times of the conventional case with a single spatial light modulator, and the size of the reconstructed image is enlarged by about 4.2. The proposed system will have wide applications in medical diagnosis, advertising, education and entertainment and other fields.

Three-dimensional lattice deformation of blue phase liquid crystals under electrostriction.

In this work, we investigate the three-dimensional lattice deformation of blue phase (BP) liquid crystals under electrostriction. Using the in situ measurement of light diffraction signals from a twinned crystal, we propose a method to experimentally determine the lattice constants of BPs under an electric field; the overlap angle in the diffraction pattern of BP twinning domains gives the ratio of lattice constants in the lateral direction of the field, which can be analyzed together with the Bragg reflection peak wavelength along the field direction to yield three-dimensional lattice constants. The obtained values are confirmed to show good agreement with the diffraction data measured from a converging monochromatic light. Furthermore, by applying the method to BPs in a thin cell and specifying the transitions of azimuthal orientation, three-dimensional lattice deformation of BP I crystals and evolution of the azimuthal orientation are clarified under the electrostriction. Results reveal that the BPs confined to thin films undergo discrete elongation along the field direction and the BP I crystal undergoes larger lattice deformation in the field-perpendicular directions than that along the field. Our work allows a relatively easy determination of three-dimensional lattice constants of deformed BP crystals under an electric field, and the obtained results provide important insights into the understanding of the electrostriction behaviour of BPs towards improvement of the electro-optical performance of BP devices in practical applications.