Zonular instability-associated morphologic features in eyes with primary angle closure disease using the swept-source anterior segment - optical coherence tomography system.

BACKGROUND: This study aims to investigate the morphologic features of the crystalline lens in Primary Angle Closure Disease (PACD) patients with zonular instability during cataract surgery using the swept-source CASIA 2 Anterior Segment-Optical Coherence Tomography (AS-OCT) system. METHODS: A total of 398 eyes (125 PACD eyes with zonular instability, 133 PACD eyes with zonular stability, and 140 cataract patient controls) of 398 patients who underwent cataract surgery combined or not glaucoma surgery between January 2021 and January 2023 were enrolled. The crystalline lens parameters were measured by CASIA2 AS-OCT. Then, logistic regression was performed to evaluate the risk factors associated with zonular instability. RESULTS: The results revealed that PACD eyes had a more anterior lens equator position, a steeper anterior curvature of lens, shorter Axial Length (AL), shallower Anterior Chamber Distance (ACD), higher Lens Vault (LV) and thicker Lens Thickness (LT), when compared to eyes in the cataract control group. Furthermore, PACD eyes in the zonular instability group had steeper front R, front Rs and Front Rf, flatter back Rf, thicker lens anterior part thickness, higher lens anterior-to-posterior part thickness ratios, shallower ACD, and greater LV, when compared to PACD eyes with zonular stability. The logistic regression analysis, which was adjusted for age and gender, revealed that zonular instability was positively correlated with anterior part thickness, lens anterior-to-posterior part thickness ratio, and LV, but was negatively correlated with lens anterior radius and ACD. CONCLUSION: Steeper anterior curvature, increased lens anterior part thickness, higher anterior-to-posterior part thickness ratio, shallower ACD, and greater LV are the anatomic features of PACD eyes associated with zonular instability.

Identification of novel cell-free RNAs in maternal plasma as preterm biomarkers in combination with placental RNA profiles.

BACKGROUND: Preterm birth (PTB) is the main driver of newborn deaths. The identification of pregnancies at risk of PTB remains challenging, as the incomplete understanding of molecular mechanisms associated with PTB. Although several transcriptome studies have been done on the placenta and plasma from PTB women, a comprehensive description of the RNA profiles from plasma and placenta associated with PTB remains lacking. METHODS: Candidate markers with consistent trends in the placenta and plasma were identified by implementing differential expression analysis using placental tissue and maternal plasma RNA-seq datasets, and then validated by RT-qPCR in an independent cohort. In combination with bioinformatics analysis tools, we set up two protein-protein interaction networks of the significant PTB-related modules. The support vector machine (SVM) model was used to verify the prediction potential of cell free RNAs (cfRNAs) in plasma for PTB and late PTB. RESULTS: We identified 15 genes with consistent regulatory trends in placenta and plasma of PTB while the full term birth (FTB) acts as a control. Subsequently, we verified seven cfRNAs in an independent cohort by RT-qPCR in maternal plasma. The cfRNA ARHGEF28 showed consistence in the experimental validation and performed excellently in prediction of PTB in the model. The AUC achieved 0.990 for whole PTB and 0.986 for late PTB. CONCLUSIONS: In a comparison of PTB versus FTB, the combined investigation of placental and plasma RNA profiles has shown a further understanding of the mechanism of PTB. Then, the cfRNA identified has the capacity of predicting whole PTB and late PTB.

Adaptive optimization technology of a conformal infrared dome based on the Von Karman surface under hypersonic conditions.

With the advent of the hypersonic era, diverse combat methods of hypersonic precision-guided weapons have been gradually developed. This study focuses on the precise design of a conformal infrared dome to accommodate different working conditions. To achieve this, an adaptive optimization technology for configuring conformal infrared domes is proposed, employing a multi-objective genetic algorithm. The technology enables the dome to dynamically balance its aerodynamic and imaging performance, taking into account the specific characteristics of each working condition. Moreover, it streamlines the design process of the conformal infrared domes. By optimizing the design with von Karman surfaces, we can overcome the limitations associated with the traditional quadric configuration. In order to evaluate its performance, a comparison was made with a conventional ellipsoid dome. The results indicate that, under the same working conditions, the air drag coefficient of the optimized infrared dome is reduced by 34.29% and that the peak signal-to-noise ratio of the distorted image from the infrared detection system is increased by 1.7%. We have demonstrated the effectiveness of the optimization method to balance aerodynamic performance and optical performance. Hopefully, our new method will improve the comprehensive performance of the infrared dome as well as the guidance capability of infrared detection technology.

Optical performance evaluation of an infrared system of a hypersonic vehicle in an aero-thermal environment.

At hypersonic velocities, the turbulent flow field generated by an aircraft, along with its temperature distribution, leads to significant aerodynamic optical effects that severely impede the performance of internal optical systems. This study proposes a method for analyzing the temporal characteristics of imaging degradation in a detector window infrared imaging system under different field angles of hypersonic velocity. Based on heat transfer theory, a method for solving the transient temperature field in the optical window of a high-speed aircraft is derived and established, considering unsteady thermal conduction-radiation coupling. Additionally, an optical window radiation tracing method is introduced, which directly determines the initial direction vector of light reaching the detector. This method reduces the workload of radiation transmission, significantly enhancing the efficiency of radiation calculations. The time characteristics of image degradation caused by aero-optical effects in high-speed aircraft are analyzed using metrics such as peak signal-to-noise ratio, wave aberration, and point diffusion function. The results demonstrate that as working time increases and the viewing angle widens, the impact of aero-optics on the aircraft imaging system becomes more severe. Moreover, compared to the aerodynamic light transmission effect, the aerodynamic thermal radiation effect has a more detrimental influence on imaging quality.

Hierarchical deconvolution dehazing method based on transmission map segmentation.

Images captured in fog are often affected by scattering. Due to the absorption and scattering of light by aerosols and water droplets, the image quality will be seriously degraded. The specific manifests are brightness decrease, contrast decrease, image blur, and noise increase. In the single-image dehazing method, the image degradation model is essential. In this paper, an effective image degradation model is proposed, in which the hierarchical deconvolution strategy based on transmission map segmentation can effectively improve the accuracy of image restoration. Specifically, the transmission map is obtained by using the dark channel prior (DCP) method, then the transmission histogram is fitted. The next step is to divide the image region according to the fitting results. Furthermore, to more accurately recover images of complex objects with a large depth of field, different levels of inverse convolution are adopted for different regions. Finally, the sub-images of different regions are fused to get the dehazing image. We tested the proposed method using synthetic fog images and natural fog images respectively. The proposed method is compared with eight advanced image dehazing methods on quantitative rating indexes such as peak signal-to-noise ratio (PSNR), structural similarity (SSIM), image entropy, natural image quality evaluator (NIQE), and blind/referenceless image spatial quality evaluator (BRISQUE). Both subjective and objective evaluations show that the proposed method achieves competitive results.

CircZSWIM4 facilitates tumor development in lung adenocarcinoma by targeting miR-370-3p and miR-873-5p to regulate the axis of FOXM1/ß-catenin.

Circular RNA (circRNA) is a kind of RNA generated by a covalently closed loop and possesses sophisticated capacities of gene regulation in tumorigenesis and development. However, the role of circZSWIM4 on lung adenocarcinoma (LUAD) remains largely unclear. In the present study, we used reverse transcription-qPCR (RT-qPCR) to examine whether circZSWIM4 was significantly overexpressed in LUAD cells. The impacts of circZSWIM4 on the properties of proliferation, apoptosis and migration were assessed by loss-of and gain-of-function assays, such as CCK-8 experiments, flow cytometry analysis and wound healing experiments. Moreover, TOP/FOP flash experiments and FISH experiments were carried out to prove that circZSWIM4 stimulated the Wnt/ß-catenin pathway. Downstream targets of circZSWIM4 were forecasted by bioinformatics tools and validated by RNA immunoprecipitation (RIP), RNA pulls down as well as luciferase reporter experiments. Forkhead box M1 (FOXM1) was confirmed to be the corporate targets of miR-370-3p and miR-873-5p. Through co-IP assay, we verified the combination between FOXM1 and ß-catenin. Totally, circZSWIM4 activated the Wnt/ß-catenin pathway by targeting miR-370-3p and miR-873-5p to regulate FOXM1 and ß-catenin and facilitated the progression of LUAD.

Psychological stress induces moderate pathology in the ganglion cell layer in mice.

Purpose: Primary open-angle glaucoma (POAG) is a condition with unclear pathogenesis. Researchers have observed an increased incidence of young Chinese POAG patients who manifest significant psychological stress while their intraocular pressure (IOP) is normal or close to normal; we hypothesize that psychological stress may play a causal role in initiating POAG. Methods: Twenty-four male C57BL/6 mice were included and divided randomly into two groups. A chronic unpredictable mild stress (CUMS) mouse model was established to evaluate the effect of psychological stress on glaucoma-related retinal pathologies. Body weight and IOP were recorded weekly. At 5 weeks after the CUMS procedure, a behavior test, serum corticosterone level, retinal nerve fiber layer (RNFL) thickness, retinal ganglion cell (RGC) number and neurotrophic factor expression were evaluated and compared between the CUMS group and the control group. Results: CUMS exposure induced depression-like behaviors, lighter body weight, and increased serum corticosterone levels in mice. RNFL thinning and neural cell loss in the ganglion cell layer (GCL) were observed in CUMS mice without significant IOP elevation. Decreased mRNA expression and protein levels of neurotropic factors in retinas of CUMS mice were observed, especially brain-derived neurotrophic factor (BDNF). Conclusions: The CUMS mouse model demonstrated that psychological stress induced glaucoma-like changes in the retinas of CUMS mice. The mechanism by which psychological stress induces retina defects may be due to a reduced expression of retinal neurotropic factors. Thus, we conclude that psychological stress is causally associated with POAG.

Evaluation of MYRF as a candidate gene for primary angle closure glaucoma.

PURPOSE: Primary angle-closure glaucoma (PACG) is a leading cause of blindness. Despite tremendous human effort and financial input, no definitive causative gene has been identified either through genome-wide association or Mendelian family studies. In the current study, novel candidate genes for PACG were investigated by studying the variants of nanophthalmos-associated genes. METHODS: A case-control study was conducted that included 45 PACG patients and 12 normal controls with short axial length (AL, less than 23.5 mm but more than 20.5 mm). Whole-exome sequencing (WES) was performed to screen the variants in previously identified nanophthalmos-associated genes, as well as other risk genes. RESULTS: The age range of the 45 PACG patients was 24 to 80 years, with an average AL of 21.87±0.65 mm (range: 20.54-23.45 mm) in the right eye and 21.89±0.64 mm (range 20.60-23.23 mm) in the left eye. Four novel myelin regulatory factor (MYRF) gene missense variants (p.G117S, p.H1057R, p.H230R, and p.R316C) were identified in four out of the 45 enrolled PACG patients, respectively. No MYRF or other nanophthalmos-associated gene variants were detected in the 12 normal controls. CONCLUSIONS: An appropriate approach was adopted to investigate the genetics of PACG through nanophthalmos-associated genes. A genetic variant, MYRF, was identified in four out of 45 PACG patients, which might be a novel candidate gene for PACG.

Transmissive mid-infrared achromatic bifocal metalens with polarization sensitivity.

Metasurfaces have shown great potential in versatile areas such as vortex-beam generators, metalenses, holograms and so on. However, chromatic error hinders metasurfaces, especially metalenses, from wider applications. In this paper, we demonstrate a novel design for a transmissive mid-infrared achromatic bifocal metalens with polarization sensitivity. The compensation phase is used to eliminate the chromatic aberration. Simulation results show that, over a continuous waveband from 3.9 to 4.6µm, the focal length only changes by 2.26% with an average focusing efficiency of about 18%. This work can push the practical application of mid-infrared metasurfaces.

Aberration characteristic correlation configuration optimization of a conformal dome based on the von Karman surface.

In this paper, the von Karman surface is used in the configuration design of the infrared conformal dome to improve its aerodynamic performance. The principle of differential geometry is used to study the geometric characteristics of the von Karman dome. Additionally, by using ray tracing, the geometric aberrations and wave aberrations of the von Karman dome are analyzed. Further, considering the geometric characteristics and aberration characteristics, an optimization method for the configuration of the von Karman dome is proposed. To prove the effectiveness of the optimization method, the aberrations introduced by the conformal dome after the configuration optimization and the original von Karman dome are compared. The comparison showed that the geometric aberration of the optimized conformal dome is reduced by 43.68%. The optimization method can significantly correct the aberration introduced by the von Karman dome and improve the guidance capability of infrared detection technology.

Time-accuracy imaging quality prediction method for an infrared detection system under hypersonic conditions.

The imaging quality of infrared detection systems over time directly affects their ability to track targets accurately. In this study, a prediction scheme for the image quality of infrared detection system under hypersonic conditions based on time accuracy has been developed. Further, based on the time discretization, a calculation model has been established for the prediction scheme to perform numerical simulation. In particular, for verifying the reliability of this prediction method and the associated numerical calculation model, a comparison has been made between the numerical simulation results and the wind tunnel test results. The maximum error of the comparison result is less than 4.5%, and the reliability of the method proposed in this paper has been proved.

Analog optical deconvolution computing for wavefront coding based on nanoantennas metasurfaces.

Analog optical computing based on metasurfaces has attracted much attention for achieving high-speed calculating without the electronic processing unit. Wavefront coding imaging systems involve the joint design of an encoded image-capturing module and decoding postprocessing algorithms to obtain a required final image. The decoding postprocessing algorithms, as a typical deconvolution computation, require an additional electronic processing unit to yield a high-quality decoded image. We demonstrate an analog optical deconvolution computing kernel based on nanoantennas metasurfaces for the postprocessing calculation of wavefront coding systems. Numerical simulations are presented to prove that the encoded point spread function can be refocused through a designed optical computing metasurface. The proposed approach opens an opportunity for real-time recovering images in wavefront coding optical systems.

Myelin regulatory factor deficiency is associated with the retinal photoreceptor defects in mice.

Previously, we reported the myelin regulatory factor (MYRF) as a candidate gene for nanophthalmos. We have also produced Myrf knockdown (Myrf+/-) mouse strain to investigate the cellular and molecular phenotypes of reduced MYRF expression in the retina. Myrf+/- mouse strain was generated using the CRISPR/Cas9 system. Optomotor response system, electroretinogram (ERG), spectral-domain optical coherence tomography (SD-OCT), histology, and immunohistochemistry were performed to evaluate retinal spatial vision, electrophysiological function, retinal thickness, and pathological changes in cone or rod photoreceptors, respectively. RNA sequencing (RNA-seq) was performed to investigate the underlying molecular mechanism linking Myrf deficiency with photoreceptor defects. The genotype and phenotype of CRISPR/Cas9-induced Myrf+/- mice and their offspring were comprehensively investigated. Photoreceptor defects were detected in the retinas of Myrf+/- mice. Visual acuity and ERG responses were decreased in Myrf+/- mice compared with the control mice (Myrf+/+). The loss of cone and rod neurons was proportional to the decreased outer nuclear layer (ONL) thickness. Moreover, RNA-seq revealed that phototransduction and estrogen signaling pathways played important roles in the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Myrf+/- mouse strain provides a good model to investigate the function of the MYRF gene. Photoreceptor defects with impaired functions of spatial vision and retinal electrophysiology indicate an important role played by MYRF in retinal development. Alterations in phototransduction and estrogen signaling pathways play important roles in linking Myrf deficiency with retinal photoreceptor defects.

Anterior vitrectomy, phacoemulsification cataract extraction and irido-zonulo-hyaloid-vitrectomy in protracted acute angle closure crisis.

PURPOSE: To describe a modified surgical approach with anterior vitrectomy, phacoemulsification (phaco) cataract extraction and irido-zonulo-hyaloid-vitrectomy (IZHV) in protracted acute angle closure crisis (AACC). PATIENTS AND METHODS: Non-comparative, retrospective case series including 21 eyes in 19 consecutive cases of protracted AACC, which persists for at least 7 days despite maximal medical and laser therapies, were included in this study. All patients underwent a modified surgical procedure with anterior vitrectomy, phaco cataract extraction, IOL implantation, goniosynechialysis (GSL) and IZHV, using modest phaco dynamic parameters with intraocular pressure (IOP) set at 30 mmHg through the procedure using Centurion® Vision System equipped with active fluidics while the anterior vitrectomy was set at 4000 or 5000 rpm. IOP and anterior chamber space were maintained through the procedure using ophthalmic viscosurgical device (OVD) injected through paracentesis whenever the Phaco or I/A probe was withdrawn from within the anterior chamber. Medical history, visual acuity (VA), IOP and anterior and posterior segment findings were recorded and compared before and after surgical treatment. RESULTS: The average age of all patients was 60.05 years old, while the average period of persistent AACC was 20.05 days. Preoperatively, the average IOP of all included eyes was 44.40 ± 8.42 mmHg despite maximal topical and systemic anti-glaucoma medications and/or laser surgeries, while the average VA was 1.46 ± 0.88 (log MAR). Postoperatively, IOP was well controlled in all patients with an average IOP at 12.06 ± 3.07 mmHg without any anti-glaucoma medications at follow-ups, which was decreased significantly from that in preoperative measurements (P < 0.001). Visual acuity was improved significantly at final follow-up with an average postoperative VA at 0.74 ± 0.77 (log MAR, P < 0.001). Anterior segment inflammation was surprisingly mild with no or minimal inflammatory cells or exudates. Anterior segment configuration was resolved in all the cases. There was no recurrent IOP spike, anterior chamber shallowing or severe complications during an average follow-up of 5.38 months (ranging from 3 to 6 months). CONCLUSIONS: Protracted AACC is a complex situation while a modified surgical strategy of anterior vitrectomy, phaco cataract extraction and IZHV provides a safe and efficient solution.

Evaluating imaging quality of optical dome affected by aero-optical transmission effect and aero-thermal radiation effect.

The imaging quality of the aerodynamically heated optical dome was evaluated under the comprehensive influence of aero-optical transmission effect and aero-thermal radiation effect. The ray propagating algorithm based on the fourth order Runge-Kutta method was used to trace the target ray and the thermal radiation ray of the optical dome. Three imaging quality evaluation parameters were proposed to evaluate aero-optical effect: Modulation transfer function (MTF), irradiance, peak signal-to-noise ratio (PSNR) of distorted images. The results show that: as the flight speed increased, the MTF decreased observably compared with the diffraction-limit MTF, the irradiance on the photosensitive surface of the detector increased gradually, and the distorted imaging quality under the influence of the comprehensive aero-optical effect gradually deteriorated. However, as the thickness of the optical dome increased, the MTF decreased sharply and the irradiance decreased gradually, that indicated the aero-optical transmission effect was reinforced and the aero-thermal radiation effect was weakened. The imaging quality improved with thickness increasing. The influence of aero-thermal radiation effect on the PSNR of the image was more serious than that of the aero-optical transmission effect.

Analysis of a highly efficient phase-locking stabilization method for electro-optic comb generation.

We theoretically show that a slightly modified Pound-Drever-Hall (PDH) stabilization scheme can lead to the optimum time-domain characteristics for electro-optic comb generators (EOCG). The ideal locking point is located by analyzing the EOCG output pulse width. By summing up the electrical field reflected by the EOCG front mirror, a model of the phase-locking error signal is derived with the Jacobi-Anger identical transformation. The simulation and experiment show that the zero-locking point of the error signal of the modified scheme coincides well with the ideal locking point in contrast with the direct application of the PDH scheme. Finally, a power efficiency of up to 2.9% is achieved with this EOCG stabilization scheme. A relative instability of better than 2.6×10-8 is demonstrated by a dual comb interferometer with fixed paths. The Allan deviations of the comb mode frequencies are smaller than 2.8×10-9 and 1.1×10-10 for average times of 1 and 100 s, respectively.

Elevated intraocular pressure causes cellular and molecular retinal injuries, advocating a more moderate intraocular pressure setting during phacoemulsification surgery.

PURPOSE: To evaluate the cellular and molecular retinal injuries induced by various intraocular pressure (IOP) settings in a mouse model of acute ocular hypertension (AOH), and to advise using a more moderate target IOP during phacoemulsification (phaco) surgery. METHODS: A mouse model of AOH that mimics a transient IOP elevation during phacoemulsification cataract surgery was established. Six groups with various settings of target IOP were included. Retinal tissues were assessed with terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end-labeling (TUNEL) staining for neuron loss, immunofluorescence with Iba1 for microglia activation, and quantitative real-time polymerase chain reaction analysis with tight junction proteins (claudin-3 and claudin-5) or classic inflammation markers (IL-1ß and eNOS) for impairment of the blood-retinal barrier (BRB) and inflammatory injury. RESULTS: Compared with those in the 45-mmHg IOP group, significantly increased number of neurons loss and increased microglia activation were observed in 90-mmHg IOP group. In addition, the expression of claudin-3 and claudin-5 was significantly decreased, while the expression of IL1-ß and eNOS was up-regulated, indicating impairment of the BRB and inflammatory injury in the retina. Furthermore, these findings of neuron loss, microglia activation, and inflammation in the 90-mmHg groups were exacerbated when an IOP-induced retinal injury was established 5 days earlier, while those in the 45-mmHg groups remained almost unchanged. CONCLUSIONS: In conclusion, these results showed that a relatively commonly used high IOP setting (90 mmHg) could induce significantly more serious retinal injury. An IOP setting around 45 mmHg is relatively safe and might be recommended in phaco surgery, especially in patients with advanced glaucoma, previous acute angle closure crisis, or other diseases with fragile retina and optic nerve.

Dual-wavelength digital holographic phase and fluorescence microscopy combining with Raman spectroscopy for micro-quartz pieces-based dual-channel encoded suspension array.

Dual-wavelength digital holographic phase and fluorescence microscopy (DW-DHPFM), combining with Raman spectroscopy, is designed to achieve the detection and analysis of biomolecules with a new dual-channel encoding method. This employs the Raman reporter molecules assembled micro-quartz pieces (MQPs) as microcarriers of suspension array (SA). The dual-wavelength digital holographic phase microscopy (DW-DHPM) and Raman spectroscopy are served as the decoding platforms, and the fluorescence microscopy is used to quantify target analytes. Considering the independence between encoding and label signal, the above two encoding channels could effectively avoid the crosstalk in immunoassay process, and the combination of two encoding methods expand the encoding capacity with a considerable magnitude. Accurate and stable decoding abilities are verified by multiplexed immunoassay experiment and the quantitative analysis of targets with high-sensitivity is confirmed by concentration gradient experiments.

Influence of altitude on aero-optic imaging quality degradation of the hemispherical optical dome.

We investigated the influence of altitude on aero-optic imaging quality degradation of the hemispherical optical dome. Boundary conditions for the aerodynamic heating effect of the optical dome were calculated by solving the Reynolds-averaged Navier-Stokes equations provided by FLUENT. The finite element model and the thermal-structure simulation results of the optical dome were obtained using ANSYS. The 3D nonuniform refractive index field of the optical dome was obtained according to the thermal-optical effect. The optical tracking method based on the fourth-order Runge-Kutta algorithm was adopted to simulate the optical transmission through the optical dome. The Strehl ratio (SR), encircled energy, distorted target images, and peak signal-to-noise ratio were presented for imaging quality evaluation. The variation rules of these imaging quality evaluation parameters were obtained in the altitude range of 0-45 km. The results showed that, in the same flight conditions, with the increase of altitude, peak signal-to-noise ratio (PSNR) of the distorted image, and SR result were increased, and radiuses of dispersion spots, including 80% energy, were decreased; therefore, the influence of aero-optics effect on imaging quality degradation was gradually weakened.

Nonlinear Errors Resulting from Ghost Reflection and Its Coupling with Optical Mixing in Heterodyne Laser Interferometers.

Even after the Heydemann correction, residual nonlinear errors, ranging from hundreds of picometers to several nanometers, are still found in heterodyne laser interferometers. This is a crucial factor impeding the realization of picometer level metrology, but its source and mechanism have barely been investigated. To study this problem, a novel nonlinear model based on optical mixing and coupling with ghost reflection is proposed and then verified by experiments. After intense investigation of this new model's influence, results indicate that new additional high-order and negative-order nonlinear harmonics, arising from ghost reflection and its coupling with optical mixing, have only a negligible contribution to the overall nonlinear error. In real applications, any effect on the Lissajous trajectory might be invisible due to the small ghost reflectance. However, even a tiny ghost reflection can significantly worsen the effectiveness of the Heydemann correction, or even make this correction completely ineffective, i.e., compensation makes the error larger rather than smaller. Moreover, the residual nonlinear error after correction is dominated only by ghost reflectance.