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Purpose: To investigate the efficacy and safety of orthokeratology (ortho-k) and repeated low-level red-light (RLRL) therapy in treating poor responders of ortho-k in myopic children. Methods: Study participants were 100 myopic children who completed two years of ortho-k treatment in a retrospective study. In the first year of ortho-k treatment (phase one), they experienced axial elongation of 0.30 mm or greater (defined as poor responders to ortho-k). Children were divided into two groups: the orthokeratology group (OK, n = 45) continued to receive ortho-k monotherapy and the combination group (OK-RLRL, n = 55) received RLRL in addition to ortho-k for the next year (phase two). Axial elongation over time between the groups was compared. Results: The mean age, male-to-female ratio, axial length (AL), and axial elongation in phase one were comparable between OK and OK-RLRL groups (all P > 0.05). During phase two, significant AL shortening was observed in the OK-RLRL group compared with children in the OK group (-0.10 ± 0.16 mm vs 0.30 ± 0.19 mm, P < 0.001). Among these 55 myopic children in the OK-RLRL group, 35 (63.6%), 25 (45.4%), 11 (20%), 6 (10.9%), and 3 (5.4%) of them had AL shortening over 0.05 mm/year, 0.10 mm/year, and 0.20 mm/year, 0.3 mm/year, and 0.4 mm/year, respectively. Older baseline age (ß = -0.02), higher treatment compliance (ß = -0.462), and AL change at 1 month (ß = 1.263) were significantly associated with less AL elongation (all P < 0.05). Conclusions: For poor responders of orthokeratology, RLRL could slow axial elongation in addition to the ortho-k treatment effect. Those who respond poorly to ortho-k with elder age might benefit more from combined therapy.
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Large language models (LLMs), a natural language processing technology based on deep learning, are currently in the spotlight. These models closely mimic natural language comprehension and generation. Their evolution has undergone several waves of innovation similar to convolutional neural networks. The transformer architecture advancement in generative artificial intelligence marks a monumental leap beyond early-stage pattern recognition via supervised learning. With the expansion of parameters and training data (terabytes), LLMs unveil remarkable human interactivity, encompassing capabilities such as memory retention and comprehension. These advances make LLMs particularly well-suited for roles in healthcare communication between medical practitioners and patients. In this comprehensive review, we discuss the trajectory of LLMs and their potential implications for clinicians and patients. For clinicians, LLMs can be used for automated medical documentation, and given better inputs and extensive validation, LLMs may be able to autonomously diagnose and treat in the future. For patient care, LLMs can be used for triage suggestions, summarization of medical documents, explanation of a patient's condition, and customizing patient education materials tailored to their comprehension level. The limitations of LLMs and possible solutions for real-world use are also presented. Given the rapid advancements in this area, this review attempts to briefly cover many roles that LLMs may play in the ophthalmic space, with a focus on improving the quality of healthcare delivery.
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Nonreciprocal devices are essential and crucial in optics for source protection and signal separation. A hybrid grating system consisting of a silicon grating, a graphene layer, and a silicon waveguide layer is employed to create a high-Q quasi-BIC (bound state in the continuum). Then, the high-Q properties of the quasi-BIC are harnessed to enhance the third-order nonlinear effect of silicon, thereby improving the nonreciprocal characteristics of the device. The nonreciprocal transmittance ratio of the device can be tunable by adjusting the graphene Fermi energy level, achieving tunability ranging from 0.0865 to 30.57â dB. It also enables the best performance of the device over a wider range of frequency bands. This study provides a new, to the best of our knowledge, method for designing tunable nonreciprocal devices with a wide range of potential applications.
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BACKGROUND: In adult patients with high myopia (HM), progressive axial elongation poses a significant risk for the development of subsequent ocular complications that may lead to visual impairment. Effective strategies to reduce or prevent further axial elongation in highly myopic adult patients have not been available so far. Recent studies suggested that medically lowering intraocular pressure (IOP) may reduce axial elongation. OBJECTIVE: This clinical randomised controlled trial (RCT) aims to evaluate the efficacy of medical IOP reduction in adult patients with progressive HM (PHM). TRIAL DESIGN: Single-centre, open-label, prospective RCT. METHODS: This RCT will recruit 152 participants with PHM at the Zhongshan Ophthalmic Center (ZOC). Randomised in a ratio of 1:1, participants will receive IOP-lowering eyedrops (intervention group) or will be followed without treatment (control group) for 12 months. Follow-up visits will be conducted at 1, 6 and 12 months after baseline. Only one eye per eligible participant will be included for analysis. The primary outcome is the change in axial length (AL) within the study period of 12 months. Secondary outcomes include the incidence and progression of visual field (VF) defects, changes in optic disc morphology and incidence and progression of myopic maculopathy. Difference in AL changes between the two groups will be analysed using linear regression analysis. For the secondary outcomes, a multifactor Poisson regression within a generalised linear model will be used to estimate the relative risk of progression in VF defects and myopic maculopathy, and the rate of thinning in retinal nerve fibre layer and ganglion cell-inner plexiform will be assessed through Kaplan-Meier curves and log-rank tests. ETHICS AND DISSEMINATION: Full ethics approval for this trial has been obtained from the Ethics Committee of ZOC, Sun Yat-sen University, China (ID: 2023KYPJ110). Results of this trial will be disseminated through peer-reviewed journals and conference presentations. TRIAL REGISTRATION NUMBER: NCT05850936.
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Presión Intraocular , Miopía Degenerativa , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Longitud Axial del Ojo , Progresión de la Enfermedad , Soluciones Oftálmicas , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Campos VisualesRESUMEN
Background: This study aimed to explore the postoperative myopic shift and its relationship to visual acuity rehabilitation in patients with bilateral congenital cataracts (CCs). Methods: Bilateral CC patients who underwent cataract extraction and primary intraocular lens implantations before 6 years old were included and divided into five groups according to surgical ages (<2, 2-3, 3-4, 4-5, and 5-6 years). The postoperative myopic shift rates, spherical equivalents (SEs), and the best corrected visual acuity (BCVA) were measured and analyzed. Results: A total of 1,137 refractive measurements from 234 patients were included, with a mean follow-up period of 34 months. The postoperative mean SEs at each follow-up in the five groups were linearly fitted with a mean R2 = 0.93 ± 0.03, which showed a downtrend of SE with age (linear regression). Among patients with a follow-up of 4 years, the mean postoperative myopic shift rate was 0.84, 0.81, 0.68, 0.24, and 0.28 diopters per year (D/y) in the five age groups (from young to old), respectively. The BCVA of those with a surgical age of <2 years at the 4-year visit was 0.26 (LogMAR), and the mean postoperative myopic shift rate was 0.84 D/y. For patients with a surgical age of 2-6 years, a poorer BCVA at the 4-year visit was found in those with higher postoperative myopic shift rates (r = 0.974, p = 0.026, Pearson's correlation test). Conclusion: Performing cataract surgery for patients before 2 years old and decreasing the postoperative myopic shift rates for those with a surgical age of 2-6 years may benefit visual acuity rehabilitation.
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INTRODUCTION: This study aimed to investigate the relationship between age of myopia onset and high myopia and to explore if age of onset mediated the associations of high myopia with parental myopia and time spent on electronics. METHODS: This cross-sectional study enrolled 1118 myopic patients aged 18 to 40. Information was obtained via a detailed questionnaire. Multivariable logistic regression and linear regression models were utilized to assess age of onset in relation to high myopia and spherical equivalent refractive error, respectively. Structural equation models examined the mediated effect of onset age on the association between parental myopia, time spent on electronics and high myopia. RESULTS: An early age at myopia onset was negatively correlated with spherical equivalent refractive power. Subjects who developed myopia before the age of 12 were more likely to suffer from high myopia than those who developed myopia after the age of 15. Age of myopia onset was the strongest predictor of high myopia, with an area under the curve (AUC) in Receiver Operator Characteristic (ROC) analysis of 0.80. Additionally, age of myopia onset served as a mediator in the relationships between parental myopia, electronic device usage duration, and the onset of high myopia in adulthood. CONCLUSIONS: Age of myopia onset might be the single best predictor for high myopia, and age at onset appeared to mediate the associations of high myopia with parental myopia and time spent on electronics.
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AIMS: To report the incidence and associated risk factors for developing suspected and definitive glaucoma after bilateral congenital cataract (CC) removal with a 5-year follow-up. METHODS: Secondary analysis of a prospective longitudinal cohort study. Bilateral CC patients who had undergone cataract surgery between January 2011 and December 2014 at Zhongshan Ophthalmic Centre were recruited. Suspected glaucoma was defined as persistent ocular hypertension requiring medical treatment. Definitive glaucoma was defined as accompanied by the progression of glaucomatous clinical features. According to postoperative lens status in 5 years follow-up: 130 eyes in the aphakia group; 219 in the primary intraocular lens (IOL) implantation group and 337 in the secondary IOL implantation group. The Kaplan-Meier survival and Cox regression analyses were used to explore the cumulative incidence and risk factors for suspected and definitive glaucoma. RESULTS: Three hundred fifty-one children (686 eyes) with bilateral CCs were enrolled in the study. The mean age at surgery was 1.82±2.08 years, and the mean follow-up duration was 6.26±0.97 years. Suspected and definitive glaucoma developed at a mean time of 2.84±1.75 years (range 0.02-7.33 years) postoperatively. The cumulative incidence of suspected and definitive glaucoma was 9.97% (35 of 351 patients), including 6.12% (42 eyes) for definitive glaucoma and 2.48% (17 eyes) for suspected glaucoma. Microcornea (HR 4.103, p<0.0001), CC family history (HR 3.285, p=0.001) and initial anterior vitrectomy (HR 2.365 p=0.036) were risk factors for suspected and definitive glaucoma. Gender, age at surgery, intraocular surgery frequency, length of follow-up and frequency of neodymium-doped yttrium aluminumaluminium garnet laser were non-statistically significant. Primary IOL implantation was a protective factor (HR 0.378, p=0.007). CONCLUSIONS: Identifying suspected and definitive glaucoma after bilateral CC surgery can lower the risk of secondary blindness in children. Patients with related risk factors need to pay more attention and thus reach early intervention and treatment during clinical practice. Primary IOL implantation may be a potential protective factor, need more clinical trials to be verified. TRIAL REGISTRATION NUMBER: NCT04342052.
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Extracción de Catarata , Catarata , Glaucoma , Hipertensión Ocular , Niño , Humanos , Lactante , Incidencia , Estudios de Seguimiento , Estudios Longitudinales , Estudios Prospectivos , Agudeza Visual , Complicaciones Posoperatorias , Catarata/complicaciones , Catarata/epidemiología , Catarata/congénito , Extracción de Catarata/efectos adversos , Glaucoma/diagnóstico , Glaucoma/epidemiología , Glaucoma/etiología , Hipertensión Ocular/cirugía , Factores de RiesgoRESUMEN
A single-layer graphene metamaterial consisting of a horizontal graphene strip, four vertical graphene strips, and two graphene rings is proposed to realize tunable multi-plasma-induced transparency (MPIT) by the coupled mode theory and the finite-difference time-domain method. A switch with three modulation modes is realized by dynamically adjusting the Fermi level of graphene. Moreover, the effect of symmetry breaking on MPIT is investigated by controlling the geometric parameters of graphene metamaterials. Triple-PIT, dual-PIT, single-PIT can be transformed into each other. The proposed structure and results provide guidance for applications such as designing photoelectric switches and modulators.
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BACKGROUND: Glioblastomas (GBMs) display striking dysregulation of metabolism to promote tumor growth. Glioblastoma stem cells (GSCs) adapt to regions of heterogeneous nutrient availability, yet display dependency on de novo cholesterol biosynthesis. The transcription factor Sterol Regulatory Element-Binding Protein 2 (SREBP2) regulates cholesterol biosynthesis enzymes and uptake receptors. Here, we investigate adaptive behavior of GSCs under different cholesterol supplies. METHODS: In silico analysis of patient tumors demonstrated enrichment of cholesterol synthesis associated with decreased angiogenesis. Comparative gene expression of cholesterol biosynthesis enzymes in paired GBM specimens and GSCs were performed. In vitro and in vivo loss-of-function genetic and pharmacologic assays were conducted to evaluate the effect of SREBP2 on GBM cholesterol biosynthesis, proliferation, and self-renewal. Chromatin immunoprecipitation quantitative real-time PCR was leveraged to map the regulation of SREBP2 to cholesterol biosynthesis enzymes and uptake receptors in GSCs. RESULTS: Cholesterol biosynthetic enzymes were expressed at higher levels in GBM tumor cores than in invasive margins. SREBP2 promoted cholesterol biosynthesis in GSCs, especially under starvation, as well as proliferation, self-renewal, and tumor growth. SREBP2 governed the balance between cholesterol biosynthesis and uptake in different nutrient conditions. CONCLUSIONS: SREBP2 displays context-specific regulation of cholesterol biology based on its availability in the microenvironment with induction of cholesterol biosynthesis in the tumor core and uptake in the margin, informing a novel treatment strategy for GBM.
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Glioblastoma , Humanos , Línea Celular Tumoral , Colesterol/metabolismo , Regulación de la Expresión Génica , Glioblastoma/patología , Células Madre Neoplásicas/metabolismo , Células Madre/metabolismo , Células Madre/patología , Proteína 2 de Unión a Elementos Reguladores de Esteroles/genética , Proteína 2 de Unión a Elementos Reguladores de Esteroles/metabolismo , Microambiente TumoralRESUMEN
BACKGROUND: Circular RNAs (circRNAs) have been shown to be essential for the emergence and growth of different cancers. However, further research is required to validate the function of circRNA in glioblastoma (GBM). METHODS: CircNDC80 expression in both normal brain tissues (NBTs) and glioma tissues was determined using real-time PCR. The impact of circNDC80 on GBM cell proliferation, migration, and invasion was then confirmed by CCK-8, colony formation, EdU incorporation, Transwell, and wound healing assays. To determine how circNDC80 affects the capacity of glioma stem cells (GSCs) to maintain their stemness and self-renewal, a CellTiter-Glo assay, clonogenic assay and extreme limiting dilution assay were utilized. To ascertain the impact of circNDC80 in vivo, intracranial xenograft models were established. RESULTS: When compared to NBT, glioblastoma tissue had a higher level of circNDC80 expression. In functional assays, circNDC80 promoted glioblastoma cell proliferation, migration, and invasion, while sustaining the stemness and fostering the self-renewal of glioma stem cells. In addition, a dual luciferase reporter assay and circRIP were used to verify that circNDC80 simultaneously affects the expression of ECE1 mRNA by sponging miR-139-5p, and a rescue experiment was used to verify the above results further. CONCLUSIONS: According to our research, circNDC80 is an oncogenic factor that promotes glioblastoma through the miR-139-5p/ECE1 pathway. This implies that circNDC80 may be employed as a novel therapeutic target and a possible predictive biomarker.
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Neoplasias Encefálicas , Glioblastoma , Glioma , MicroARNs , ARN Circular , Humanos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Carcinogénesis/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Transformación Celular Neoplásica , Enzimas Convertidoras de Endotelina , Glioblastoma/genética , Glioblastoma/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , ARN Circular/genética , ARN Circular/metabolismoRESUMEN
Glioblastoma (GBM) is the most lethal primary brain tumor in adults and harbors a subpopulation of glioma stem cells (GSCs). Enhancer of Zeste Homolog 2 (EZH2), a histone lysine methyltransferase, deeply involves in the stemness maintenance of GSC. However, the precise mechanism and therapeutic potential remain elusive. We postulated that the interactome of EZH2 in GSC is unique. Therefore, we performed proteomic and transcriptomic research to unveil the oncogenic mechanism of EZH2. Immunoprecipitation and mass spectrometry were used to identify proteins that co-precipitate with EZH2. We show that EZH2 binds to heterochromatin protein 1 binding protein 3 (HP1BP3) in GSCs and impairs the methylation of H3K9. Overexpression of HP1BP3 enhances the proliferation, self-renewal and temozolomide (TMZ) resistance of GBM cells. Furthermore, EZH2 and HP1BP3 co-activate WNT7B expression thereby increasing TMZ resistance and stemness of GBM cells. Importantly, inhibition of WNT7B autocrine via LGK974 effectively reverses the TMZ resistance. Our work clarifies a new oncogenic mechanism of EZH2 by which it interacts with HP1BP3 and epigenetically activates WNT7B thereby promoting TMZ resistance in GSCs. Our results provide a rationale for targeting WNT/ß-catenin pathway as a promising strategy to overcome TMZ resistance in GSCs.
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Neoplasias Encefálicas , Glioblastoma , Humanos , Temozolomida/farmacología , Temozolomida/uso terapéutico , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Proteómica , Vía de Señalización Wnt , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Células Madre Neoplásicas/patología , Proteínas Wnt/metabolismoRESUMEN
This paper proposes a novel and perfect absorber based on patterned graphene and vanadium dioxide hybrid metamaterial, which can not only achieve wide-band perfect absorption and dual-channel absorption in the terahertz band, but also realize their conversion by adjusting the temperature to control the metallic or insulating phase of VO2. Firstly, the absorption spectrum of the proposed structure is analyzed without graphene, where the absorption can reach as high as 100% at one frequency point (f = 5.956 THz) when VO2 is in the metal phase. What merits attention is that the addition of graphene above the structure enhances the almost 100% absorption from one frequency point (f = 5.956 THz) to a wide frequency band, in which the broadband width records 1.683 THz. Secondly, when VO2 is the insulating phase, the absorption of the metamaterial structure with graphene outperforms better, and two high absorption peaks are formed, logging 100% and 90.7% at f3 = 5.545 THz and f4 = 7.684 THz, respectively. Lastly, the adjustment of the Fermi level of graphene from 0.8 eV to 1.1 eV incurs an obvious blueshift of the absorption spectra, where an asynchronous optical switch can be achieved at fK1 = 5.782 THz and fK2 = 6.898 THz. Besides, the absorber exhibits polarization sensitivity at f3 = 5.545 THz, and polarization insensitivity at f4 = 7.684 THz with the shift in the polarization angle of incident light from 0° to 90°. Accordingly, this paper gives insights into the new method that increases the high absorption width, as well as the great potential in the multifunctional modulator.
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In order to diagnose an incipient fault in rotating machinery under complicated conditions, a fast sparse decomposition based on the Teager energy operator (TEO) is proposed in this paper. In this proposed method, firstly, the TEO is employed to enhance the envelope of the impulses, which is more sensitive to frequency and can eliminate the low-frequency harmonic component and noise; secondly, a smoothing filtering algorithm was adopted to suppress the noise in the TEO envelope; thirdly, the fault signal was reconstructed by multiplication of the filtered TEO envelope and the original fault signal; finally, sparse decomposition was used based on a generalized S-transform (GST) to obtain the sparse representation of the signal. The proposed preprocessing method using the filtered TEO can overcome the interference of high-frequency noise while maintaining the structure of fault impulses, which helps the processed signal perform better on sparse decomposition; sparse decomposition based on GST was used to represent the fault signal more quickly and more accurately. Simulation and application prove that the proposed method has good accuracy and efficiency, especially in conditions of very low SNR, such as impulses with anSNR of -8.75 dB that are submerged by noise of the same amplitude.
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Isocitrate dehydrogenase (IDH) wild-type glioblastoma (GBM) has a dismal prognosis. A better understanding of tumor evolution holds the key to developing more effective treatment. Here we study GBM's natural evolutionary trajectory by using rare multifocal samples. We sequenced 61,062 single cells from eight multifocal IDH wild-type primary GBMs and defined a natural evolution signature (NES) of the tumor. We show that the NES significantly associates with the activation of transcription factors that regulate brain development, including MYBL2 and FOSL2. Hypoxia is involved in inducing NES transition potentially via activation of the HIF1A-FOSL2 axis. High-NES tumor cells could recruit and polarize bone marrow-derived macrophages through activation of the FOSL2-ANXA1-FPR1/3 axis. These polarized macrophages can efficiently suppress T-cell activity and accelerate NES transition in tumor cells. Moreover, the polarized macrophages could upregulate CCL2 to induce tumor cell migration. SIGNIFICANCE: GBM progression could be induced by hypoxia via the HIF1A-FOSL2 axis. Tumor-derived ANXA1 is associated with recruitment and polarization of bone marrow-derived macrophages to suppress the immunoenvironment. The polarized macrophages promote tumor cell NES transition and migration. This article is highlighted in the In This Issue feature, p. 2711.
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Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/genética , Glioblastoma/patología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Isocitrato Deshidrogenasa/genética , Pronóstico , Hipoxia/genéticaRESUMEN
Double narrowband induced perfect absorption in the terahertz region is achieved in a graphene-dielectric-gold hybrid metamaterial, whose physical mechanism is analyzed using the coupled-mode theory (CMT), which agreed well with the finite-difference time-domain (FDTD) simulation. This study found that the Fermi level of graphene can be adjusted to improve the absorptivity when the refractive index (RI) nd of the chosen dielectric cannot achieve a good absorption effect. In addition, the blue shift of absorption spectrum can be used in the design of dual-frequency electro-optical switches, of which the modulation degree of amplitude (MDA) can reach as high as 94.05% and 93.41%, indicating that this is a very promising electro-optical switch. Most significantly, the RI sensing performance is investigated, which shows an ultra-high absorption sensitivity SA = 4.4°/RIU, wavelength sensitivity Sλ = 9.8°/RIU, and phase shift sensitivity Sφ = 2691°/RIU. At last, an interesting finding is that the two peaks (R1 and R2) of plasmon-induced absorption (PIA) show different polarization characteristics (insensitive or sensitive) to the incident light angle; this polarization-sensitive is particularly important for the PIT/PIA-based optical polarizers. Undoubtedly, this paper is of great significance to the research and design of terahertz photonic devices and sensors.
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Due to the progress in global warming, the frequency, duration and intensity of climate extremes are increasing. As one of these extremes, heat waves influence the well-being of human beings and increase societies' energy consumption. The Water-Cooling Island (WCI) effect of urban water bodies (UWBs) is important in urban heat wave mitigation. In this paper, the impact of WCI, especially the landscape pattern of the surrounding area, was explored. The results indicate that water bodies with a larger total area and simpler shape have a longer cooling effect. In the areas surrounding UWBs, a lower percentage or discrete distribution of impervious surfaces or green land provide a longer cooling effect. The amplitude of WCI is mainly decided by the impervious surface in the surrounding areas. A lower percentage or discrete distribution of impervious surfaces or green land leads to a smaller-amplitude WCI. The gradient is impacted by the shape of the UWB and surrounding green land. A complex shape and discrete distribution of green land lead to a higher gradient of WCI. The linear regress model was significant in terms of WCI range and gradient, while the model of WCI amplitude was not significant. This indicates that WCI is directly decided by impact factors through gradient and range. The conclusions provide a methodology for WCI prediction and optimization, which is important when mitigating summer heat waves.
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Calor , Tecnología de Sensores Remotos , China , Ciudades , Humanos , Estaciones del Año , AguaRESUMEN
Aiming at non-stationary signals with complex components, the performance of a variational mode decomposition (VMD) algorithm is seriously affected by the key parameters such as the number of modes K, the quadratic penalty parameter α and the update step τ. In order to solve this problem, an adaptive empirical variational mode decomposition (EVMD) method based on a binary tree model is proposed in this paper, which can not only effectively solve the problem of VMD parameter selection, but also effectively reduce the computational complexity of searching the optimal VMD parameters using intelligent optimization algorithm. Firstly, the signal noise ratio (SNR) and refined composite multi-scale dispersion entropy (RCMDE) of the decomposed signal are calculated. The RCMDE is used as the setting basis of the α, and the SNR is used as the parameter value of the τ. Then, the signal is decomposed into two components based on the binary tree mode. Before decomposing, the α and τ need to be reset according to the SNR and MDE of the new signal. Finally, the cycle iteration termination condition composed of the least squares mutual information and reconstruction error of the components determines whether to continue the decomposition. The components with large least squares mutual information (LSMI) are combined, and the LSMI threshold is set as 0.8. The simulation and experimental results indicate that the proposed empirical VMD algorithm can decompose the non-stationary signals adaptively, with lower complexity, which is O(n2), good decomposition effect and strong robustness.
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Algoritmos , Procesamiento de Señales Asistido por Computador , Análisis de los Mínimos CuadradosRESUMEN
A simple monolayer graphene metamaterial based on silicon/silica substrates is proposed, and typical triple-plasmon-induced transparency (PIT) is realized in the terahertz band. The physical mechanism is analyzed by coupled mode theory (CMT), and the results of CMT agree well with the finite-difference time-domain simulation. A multimode electro-optical switch can be designed by dynamic tuning, and the modulation degrees of its resonant frequencies are 84.0%, 87.3%, 83.0%, 88.1%, and 76.7%. In addition, triple-PIT gradually degenerates into dual-PIT with a decrease in the length of one bright mode. Interestingly, the group index can reach 770 at Ef=0.8eV, which shows that it can be designed as a slow light device with extraordinary ability. Therefore, the results of this paper are of great significance to the research and design of electro-optical switches and slow light devices in the terahertz band.
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A terahertz-band metamaterial composed of multilayer patterned graphene is proposed and triple plasmon-induced transparency is excited by coupling three bright modes with one dark mode. The Lorentz curve calculated by the coupled-mode theory agrees well with the finite-difference time-domain results. Dynamic tuning is investigated by changing the Fermi level. Multimode electro-optics switching can be designed and achieved, and the amplitude modulations of four resonance frequencies are 94.3%, 92.8%, 90.7%, and 93%, respectively, which can realize the design of synchronous and asynchronous electro-optics switches. It is hoped that these results can provide theoretical support and guidance for the future design and application of photonic and optoelectronic devices.
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The glioma immune microenvironment (GIM), consisting of glioma cells, stromal cells, and immune cells, accelerates the initiation, development, immune evasion, chemoresistance, and radioresistance of glioblastoma (GBM), whereas the immunosuppressive mechanisms of GBM have not been thoroughly elucidated to date. The glioma data downloaded from The Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA) databases were used to evaluate the composition of tumor-infiltrating immune cells (TICs) by the CIBERSORT algorithm. RNA-seq datasets from the TCGA and CGGA were used to analyze the relationship between immune scores with patients' characteristics and TICs, which showed higher ratios of tumor-inhibiting/tumor-promoting signatures (M2/M1 macrophages) along with higher immune scores. The distribution of TICs among different glioma patients and the correlation with hazard ratio (HR) analysis suggested that M2 macrophages were abundant in malignant gliomas and indicated an unfavorable prognosis. We further analyzed TCGA cases with available mutation and copy-number alteration information, which showed that the status of PTEN could influence the immune microenvironment of glioma patients. Tissue microarrays of 39 GBM patients were carried out to confirm the clinical significance of PTEN and macrophage markers. We found that the high expression of PTEN was associated with a more extended survival period of glioma patients, positively correlated with M2 macrophages and negatively with M1 macrophages. Transwell and flow cytometry analyses demonstrated that PTEN status could prevent M1 to M2 polarization and M2 macrophage recruitment of gliomas in vitro. The newly discovered immunoregulatory activity of PTEN opens innovative avenues for investigations relevant to counteracting cancer development and progression.