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In this paper, we introduce the notion of practically susceptible population, which is a fraction of the biologically susceptible population. Assuming that the fraction depends on the severity of the epidemic and the public's level of precaution (as a response of the public to the epidemic), we propose a general framework model with the response level evolving with the epidemic. We firstly verify the well-posedness and confirm the disease's eventual vanishing for the framework model under the assumption that the basic reproduction number R 0 < 1 . For R 0 > 1 , we study how the behavioural response evolves with epidemics and how such an evolution impacts the disease dynamics. More specifically, when the precaution level is taken to be the instantaneous best response function in literature, we show that the endemic dynamic is convergence to the endemic equilibrium; while when the precaution level is the delayed best response, the endemic dynamic can be either convergence to the endemic equilibrium, or convergence to a positive periodic solution. Our derivation offers a justification/explanation for the best response used in some literature. By replacing "adopting the best response" with "adapting toward the best response", we also explore the adaptive long-term dynamics.
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Número Básico de Reprodução , Doenças Transmissíveis , Epidemias , Conceitos Matemáticos , Modelos Biológicos , Humanos , Número Básico de Reprodução/estatística & dados numéricos , Epidemias/estatística & dados numéricos , Epidemias/prevenção & controle , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/transmissão , Suscetibilidade a Doenças/epidemiologia , Modelos Epidemiológicos , Evolução Biológica , Simulação por ComputadorRESUMO
In recent computer vision research, the pursuit of improved classification performance often leads to the adoption of complex, large-scale models. However, the actual deployment of such extensive models poses significant challenges in environments constrained by limited computing power and storage capacity. Consequently, this study is dedicated to addressing these challenges by focusing on innovative methods that enhance the classification performance of lightweight models. We propose a novel method to compress the knowledge learned by a large model into a lightweight one so that the latter can also achieve good performance in few-shot classification tasks. Specifically, we propose a dual-faceted knowledge distillation strategy that combines output-based and intermediate feature-based methods. The output-based method concentrates on distilling knowledge related to base class labels, while the intermediate feature-based approach, augmented by feature error distribution calibration, tackles the potential non-Gaussian nature of feature deviations, thereby boosting the effectiveness of knowledge transfer. Experiments conducted on MiniImageNet, CIFAR-FS, and CUB datasets demonstrate the superior performance of our method over state-of-the-art lightweight models, particularly in five-way one-shot and five-way five-shot tasks.
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Concentric tube robots (CTRs) are a promising prospect for minimally invasive surgery due to their inherent compliance and ability to navigate in constrained environments. Existing mechanics-based kinematic models typically neglect friction, clearance, and torsion between each pair of contacting tubes, leading to large positioning errors in medical applications. In this paper, an improved kinematic modeling method is developed. The effect of clearance on tip position during concentric tube assembly is compensated by the database method. The new kinematic model is mechanic-based, and the impact of friction moment and torsion on tubes is considered. Integrating the infinitesimal torsion of the concentric tube robots eliminates the errors caused by the interaction force between the tubes. A prototype is built, and several experiments with kinematic models are designed. The results indicate that the error of tube rotations is less than 2 mm. The maximum error of the feeding experiment does not exceed 0.4 mm. The error of the new modeling method is lower than that of the previous kinematic model. This paper has substantial implications for the high-precision and real-time control of concentric tube robots.
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As an inherent feature of vector optical field, the spatial distribution of polarization brings additional degrees of freedom to engineer the optical field and control the interaction between light and matters. Here we focus on the variation of polarization in single vector optical field, which can be defined by the trajectory on the Poincaré sphere. Based on the amplitude-phase-polarization joint modulation method we propose, vector optical field, whose variation of polarization follows arbitrary circular trajectory on the Poincaré sphere, can be generated. Moreover, the tightly focusing behaviors of the vector optical fields with the polarization varying along parallel circles on the Poincaré sphere are compared. Relations between the circular trajectory and the central intensity of the hollow focal field are concluded.
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Glaucoma is a leading cause of irreversible blindness worldwide. Reducing intraocular pressure is currently the only effective treatment. Elevated intraocular pressure is associated with increased resistance of the outflow pathway, mainly the trabecular meshwork (TM). Despite great progress in the field, the development of novel and effective treatment for glaucoma is still challenging. In this study, we reported that human induced pluripotent stem cells (iPSCs) can be cultured as colonies and monolayer cells expressing OCT4, alkaline phosphatase, SSEA4 and SSEA1. After induction to neural crest cells (NCCs) positive to NGFR and HNK1, the iPSCs can differentiate into TM cells. The induced iPSC-TM cells expressed TM cell marker CHI3L1, were responsive to dexamethasone treatment with increased expression of myocilin, ANGPTL7, and formed CLANs, comparable to primary TM cells. To the best of our knowledge, this is the first study that induces iPSCs to TM cells through a middle neural crest stage, which ensures a stable NCC pool and ensures the high output of the same TM cells. This system can be used to develop personalized treatments using patient-derived iPSCs, explore high throughput screening of new drugs focusing on TM response for controlling intraocular pressure, and investigate stem cell-based therapy for TM regeneration.
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Diferenciação Celular , Células-Tronco Pluripotentes Induzidas/citologia , Malha Trabecular/citologia , Técnicas de Cultura de Células/métodos , Linhagem Celular , Glaucoma/terapia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Malha Trabecular/metabolismo , Malha Trabecular/transplanteRESUMO
As an important nitrogen source, isocyanides have been involved in numerous organic reactions. As a result, many complicated compounds have been successfully synthesized through isocyanide chemistry. However, compared with its popular research in organic reactions, the application of isocyanides in polymerization is less investigated. In this work, a new polymerization based on isocyanide monomers is established. By simply mixing diisocyanoacetates and dialdehydes in the presence of a catalytic system of CuCl/PPh3 /organobase in dichloromethane at room temperature readily produces soluble and thermally stable oxazoline-containing polymers with moderate weight-averaged molecular weights (Mw up to 11 200) in excellent yields (up to 97%) after 6 h. Furthermore, introducing the tetraphenylethene moiety into the main chains endows the resultant polymers with aggregation-induced emission, which can function as fluorescent probes for Fe3+ ion detection with high sensitivity and selectivity. This work not only enriches the family of isocyanide-based polymerizations but also provides an efficient tool for the preparation of functional heterocycle-containing polymers.
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Aldeídos/química , Cianetos/química , Corantes Fluorescentes/química , Oxazóis/química , Polímeros/síntese química , Compostos Férricos/análise , Corantes Fluorescentes/síntese química , Íons/análise , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Polimerização , Polímeros/químicaRESUMO
Age-related cataract (ARC) is caused by the exposure of the lens to UVB which promotes oxidative damage and cell death. This study aimed to explore the role of lncRNA H19 in oxidative damage repair in early ARC. lncRNAs sequencing technique was used to identify different lncRNAs in the lens of early ARC patients. Human lens epithelial cells (HLECs) were exposed to ultraviolet irradiation; and 8-OHdG ELISA, Cell counting kit 8 (CCK8), EDU, flow cytometry and TUNEL assays were used to detect DNA damage, cell viability, proliferation and apoptosis. Luciferase assay was used to examine the interaction among H19, miR-29a and thymine DNA glycosylase (TDG) 3'UTR. We found that lncRNA H19 and TDG were highly expressed while miR-29a was down-regulated in the three types of early ARC and HLECs exposed to ultraviolet irradiation, compared to respective controls. lncRNA H19 knockdown aggravated oxidative damage, reduced cell viability and proliferation, and promoted apoptosis in HLECs, while lncRNA H19 overexpression led to opposite effects in HLECs. Mechanistically, miR-29a bound TDG 3'UTR to repress TDG expression. lncRNA H19 up-regulated the expression of TDG by repressing miR-29a because it acted as ceRNA through sponging miR-29a. In conclusion, the interaction among lncRNA H19, miR-29a and TDG is involved in early ARC. lncRNA H19 could be a useful marker of early ARC and oxidative damage repair pathway of lncRNA H19/miR-29a/TDG may be a promising target for the treatment of ARC.
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Catarata/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Timina DNA Glicosilase/genética , Envelhecimento/genética , Envelhecimento/patologia , Envelhecimento/efeitos da radiação , Apoptose/genética , Catarata/metabolismo , Catarata/patologia , Linhagem Celular , Proliferação de Células/genética , Sobrevivência Celular/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Cristalino/metabolismo , Cristalino/efeitos da radiação , Estresse Oxidativo/genética , Estresse Oxidativo/efeitos da radiação , Transdução de Sinais/efeitos da radiação , Raios Ultravioleta/efeitos adversosRESUMO
Purpose: Age-related cataract (ARC) is the leading cause of visual impairment and blindness worldwide. The apoptosis of lens epithelial cells (LECs) induced by oxidative damage is a major contributing factor to ARC. Long noncoding RNAs (lncRNAs) play important roles in various biologic processes. We aimed to explore the role of glutathione peroxidase 3 (GPX3)-antisense (AS) in ARCs. Methods: We extracted total RNAs from transparent and age-matched cataractous human lenses and detected lncRNA expression profiles using high-throughput RNA sequencing. The expression of GPX3-AS and GPX3 was detected by quantitative real-time PCR (qRT-PCR). Apoptotic proteins were detected by western blot and immunofluorescence. We treated SRA01/04 cells with H2O2 to mimic oxidative stress and induce cell apoptosis, which was analyzed by flow cytometry and TdT-mediated dUTP Nick-End Labeling (TUNEL) assay. The cell counting kit-8 (CCK-8) assay was used to detect the viability of SRA01/04 cells. The location of GPX3-AS was determined by fluorescence in situ hybridization (FISH) and cell nuclear and cytoplasmic RNA separation. Results: The lncRNA GPX3-AS, which is located in the nuclei of LECs, was downregulated in cataractous human lenses compared with control lenses, and proapoptotic proteins were expressed at high levels in the anterior lens capsules of ARC tissues. An in vitro study suggested that GPX3-AS inhibited H2O2-induced SRA01/04 cell apoptosis. As GPX3-AS is transcribed from the AS strand of the GPX3 gene locus, we further revealed its regulatory role in GPX3 expression. GPX3-AS was positively correlated with GPX3 expression. In addition, GPX3-AS inhibited H2O2-induced SRA01/04 cell apoptosis by upregulating GPX3 expression. Conclusions: In summary, our study revealed that GPX3-AS downregulated the apoptosis of LECs via promoting GPX3 expression, implying a novel therapeutic target for ARCs.
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Envelhecimento/genética , Apoptose/genética , Catarata/genética , Células Epiteliais/patologia , Glutationa Peroxidase/genética , Cristalino/patologia , RNA Longo não Codificante/metabolismo , Regulação para Cima/genética , Cápsula Anterior do Cristalino/metabolismo , Cápsula Anterior do Cristalino/patologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Epiteliais/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Peróxido de Hidrogênio/toxicidade , RNA Longo não Codificante/genética , Regulação para Cima/efeitos dos fármacosRESUMO
OBJECTIVE: To explore the impact of plasma homocysteinemia(Hcy) on contrast-induced nephropathy (CIN) after percutaneous coronary intervention (PCI) in acute coronary syndrome (ACS) patients. METHODS: Consecutive 684 ACS patients undergoing first PCI in our department between January 2013 and December 2014 were prospectively enrolled.Patients were divided into 2 groups according to the pre-procedural plasma Hcy level: high-Hcy group (Hcy≥10 µmol/L, n=404) and control group (Hcy<10 µmol/L, n=280). The CIN was defined as serum creatinine ≥ 44.2 µmol/L or 25% increase compared to baseline within 48-72 h after PCI.The baseline clinical data and the ratio of CIN were compared between the 2 groups.Multivariate logistic regression analysis was used to define the independent risk factors for CIN. RESULTS: CIN occurred in 133(19.4%) out of 684 enrolled patients, and the incidence of CIN was significantly higher in high Hcy group than in the control group (22.0%(89/404)vs. 15.7%(44/280), P=0.040). After adjusting the confounding factors, including age, acute myocardial infarction, co-morbidities(hypertension, diabetes mellitus, and old myocardial infarction), laboratory examination (level of cystatin C and uric acid), glomerular filtration rate, left ventricular ejection fraction, angiographic and procedural characteristics (3 diseased vessels, multiple stent implantation), treatment at admission (spironolactone, digoxin), multivariate logistic regression analysis showed that high Hcy was independently associated with the development of CIN (OR=1.70, 95%CI 1.60-2.64, P=0.021). CONCLUSION: Elevated Hcy prior PCI is an independent risk factor of CIN in ACS patients undergoing first PCI.
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Hiper-Homocisteinemia , Síndrome Coronariana Aguda , Diabetes Mellitus , Taxa de Filtração Glomerular , Humanos , Incidência , Nefropatias , Infarto do Miocárdio , Intervenção Coronária Percutânea , Fatores de Risco , Função Ventricular EsquerdaRESUMO
OBJECTIVE: To explore the relationship between hyperhomocysteinemia (H-Hcy) and long-term outcome of coronary artery disease (CAD) patients after drug-eluting stent (DES) implantation in a single centre. METHODS: A total of 1 408 consecutive patients implanted with DES in our department between March 2011 and January 2013 were enrolled in this prospective study. Patients were stratified into H-Hcy (Hcy≥10 µmol/L, n=798, 56.7%) and non-H-Hcy group (Hcy<10 µmol/L, n=610, 43.3%). The clinical characteristics, coronary artery lesions, SYNTAX score and 1-year major adverse cardiac and cerebrovascular events (MACCE) were compared between the two groups. RESULTS: Compared with non-H-Hcy group, coronary artery stenosis was severer as shown by higher diseased arteries (2.11±0.87 vs. 1.91±0.82, P<0.001), higher incidence of three diseased arteries (39.7% vs. 29.5%, P<0.001) and higher SYNTAX score (36.99±29.66 vs. 27.39±22.70, P=0.001) in H-Hcy group. The 1-year incidence of MACCE was also higher in H-Hcy group compared with non-H-Hcy group(18.4% vs. 8.9%, P<0.001). Multivariate Cox analysis showed that diabetes mellitus (OR=1.530, 95%CI 1.142-2.050, P=0.004), age (OR=1.065, 95%CI 1.038-1.093; P<0.001), and Hcy (OR=1.019, 95%CI 1.005-1.033, P=0.009) are the independent predictors for 1-year MACCE. CONCLUSION: High Hcy level is correlated with the severity of coronary artery stenosis, and serves as an independent predictor of MACCE after stenting in CAD patients.
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Doença da Artéria Coronariana , Stents Farmacológicos , Homocisteína , Humanos , Estudos Prospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
The purpose of this study was to prepare mackerel peptides (MPs) with calcium-binding capacity through an enzyme method and to investigate the potential role they play in improving the bioavailability of calcium in vitro. The calcium-binding capacity, degree of hydrolysis (DH), molecular weight (MW), and charge distribution changes with the enzymolysis time of MPs were measured. The structural characterization of mackerel peptide-calcium (MP-calcium) complexes was performed using spectroscopy and morphology analysis. The results showed that the maximum calcium-binding capacity of the obtained MPs was 120.95 mg/g when alcalase was used for 3 h, with a DH of 15.45%. Moreover, with an increase in hydrolysis time, the MW of the MPs decreased, and the negative charge increased. The carboxyl and amino groups in aspartic (Asp) and glutamate (Glu) of the MPs may act as calcium-binding sites, which are further assembled into compact nanoscale spherical complexes with calcium ions through intermolecular interactions. Furthermore, even under the influence of oxalic acid, MP-calcium complexes maintained a certain solubility. This study provides a basis for developing new calcium supplements and efficiently utilizing the mackerel protein resource.
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OBJECTIVES: To characterize choroidal vascular changes in children with different refractive status. METHODS: A study including 5864 children aged 6-9 years was performed to investigate the choroidal vascular index (CVI) in myopic, emmetropic and hyperopic eyes. Each participant had a comprehensive ocular examination with cycloplegic autorefraction performed, axial length (AL) measured and Swept Source-Optical Coherence Tomography (SS-OCT) scans acquired. Choroidal thickness (ChT) was measured by built-in software, and CVI was calculated using a previously validated self-developed algorithm. RESULTS: The mean ChT and CVI were 275.88 ± 53.34 µm and 34.91 ± 3.83 in the macula region, and 191.96 ± 46.28 µm and 32.35 ± 4.21 in the peripapillary region. CVI was significantly lowest for myopes, followed by emmetropes and hyperopes (P < 0.001). CVI varied between different sectors separated by the Early Treatment of Diabetic Retinopathy Study (ETDRS) grid (P < 0.001). Macular CVI decreased horizontally from nasal to temporal quadrant with lowest in center fovea, and vertically from superior to inferior quadrants. Peripapillary CVI was highest in the nasal and lowest in the inferior sector. Multiple regression showed that spherical equivalent (SE), AL, intraocular pressure (IOP), ChT, age, and gender were significantly related to CVI (P < 0.05). CONCLUSIONS: In children, the distribution of CVI in the posterior pole is not uniform. A decreased CVI was observed from hyperopia to myopia and was associated with decreased SE, elongated AL, and choroidal thinning. Further study of changes in CVI during myopia onset and progression is required to better understand the role of the choroidal vasculature in myopia development.
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Hiperopia , Macula Lutea , Miopia , Criança , Humanos , Fóvea Central , Refração Ocular , Corioide/irrigação sanguínea , Tomografia de Coerência Óptica/métodosRESUMO
The increasing prevalence of myopia worldwide presents a significant public health challenge. A key strategy to combat myopia is with early detection and prediction in children as such examination allows for effective intervention using readily accessible imaging technique. To this end, we introduced DeepMyopia, an artificial intelligence (AI)-enabled decision support system to detect and predict myopia onset and facilitate targeted interventions for children at risk using routine retinal fundus images. Based on deep learning architecture, DeepMyopia had been trained and internally validated on a large cohort of retinal fundus images (n = 1,638,315) and then externally tested on datasets from seven sites in China (n = 22,060). Our results demonstrated robustness of DeepMyopia, with AUCs of 0.908, 0.813, and 0.810 for 1-, 2-, and 3-year myopia onset prediction with the internal test set, and AUCs of 0.796, 0.808, and 0.767 with the external test set. DeepMyopia also effectively stratified children into low- and high-risk groups (p < 0.001) in both test sets. In an emulated randomized controlled trial (eRCT) on the Shanghai outdoor cohort (n = 3303) where DeepMyopia showed effectiveness in myopia prevention compared to NonCyc-based model, with an adjusted relative reduction (ARR) of -17.8%, 95% CI: -29.4%, -6.4%. DeepMyopia-assisted interventions attained quality-adjusted life years (QALYs) of 0.75 (95% CI: 0.53, 1.04) per person and avoided blindness years of 13.54 (95% CI: 9.57, 18.83) per 1 million persons compared to natural lifestyle with no active intervention. Our findings demonstrated DeepMyopia as a reliable and efficient AI-based decision support system for intervention guidance for children.
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Robot grippers that lack physical compliance have a difficult time dealing with uncertainty, such as fragile objects that may not have well-defined shapes. Existing soft robotic grippers require a large empty workspace for their actuated fingers to curl around the objects of interest, limiting their performance in clutter. This article presents a three-dimensional structure that exhibits negative stiffness in every bending direction used as fingers in a class of soft robotic grippers. Our approach exploits a compliant mechanism in a conical shape such that a transverse external contact force causes the fingers to bend toward the contact, enabling passive conformation for an adaptive grasp, even in clutter. We show analytically and experimentally that the proposed fingers have a negative bending response and that they conform to objects of various diameters. We demonstrate a soft robotic gripper with three self-conforming fingers performing the following: (1) fingertip grasping, (2) power grasping, and (3) semipassive grasping in clutter. Grasping experiments focus on picking fruits, which exemplify delicate objects with unmodeled shapes with significant variation. The experimental results reveal the ability of the self-conforming structure to smoothly envelope a broad range of objects and demonstrate a 100% grasp success rate in the experiments performed. The proposed passively conforming fingers enable picking of complex and unknown geometries without disturbing nearby objects in clutter and without the need for complex grasping algorithms. The proposed structures can be tailored to deform in desired ways, enabling a robust strategy for the engineering of physical compliance for adaptive soft structures.
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Robótica , Robótica/métodos , Desenho de Equipamento , Dedos/fisiologia , Fenômenos Mecânicos , Força da Mão/fisiologiaRESUMO
BACKGROUND: Suturing and knotting in Natural Orifice Transluminal Endoscopic Surgery (NOTES) requires the robot not only to be able to work with multiple manipulators but also to have a high degree of dexterity. However, little attention has been paid to the design and enhancement of dexterity in multi-manipulated robots. METHODS: In this paper, the dexterity of a new dual-manipulator collaborative continuum robot in collaborative space is analyzed and enhanced. A kinematic model of the continuum robot was developed. The dexterity function of the robot is evaluated based on the concepts of the low-Degree-of-Freedom Jacobian matrix. Then an Adaptive Parameter Gray Wolf Coupled Cuckoo Optimization Algorithm with faster convergence and higher accuracy is innovatively proposed to optimize the objective function. Finally, experiments demonstrate that the dexterity of the optimized continuum robot is enhanced. RESULTS: The optimization results show that the optimized dexterity is 24.91% better than the initial state. CONCLUSION: Through the work of this paper, the robot for NOTES can perform suturing and knot more dexterously, which has significant implications for the treatment of digestive tract diseases.
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Cirurgia Endoscópica por Orifício Natural , Robótica , Robótica/métodos , Desenho de Equipamento , Cirurgia Endoscópica por Orifício Natural/métodos , Procedimentos NeurocirúrgicosRESUMO
OBJECTIVE: This study explored the clinical features and immune responses of children with primary ciliary dyskinesia (PCD) during pneumonia episodes. METHODS: The 61 children with PCD who were admitted to hospital because of pneumonia were retrospectively enrolled into this study between April 2017 and August 2022. A total of 61 children with pneumonia but without chronic diseases were enrolled as the control group. The clinical characteristics, levels of inflammatory indicators, pathogens, and imaging features of the lungs were compared between the two groups. RESULTS: The PCD group had higher levels of lymphocytes (42.80% versus 36.00%, p = 0.029) and eosinophils (2.40% versus 1.25%, p = 0.020), but lower neutrophil counts (3.99 versus 5.75 × 109/L, p = 0.011), percentages of neutrophils (46.39% versus 54.24%, p = 0.014), CRP (0.40 versus 4.20 mg/L, p < 0.001) and fibrinogen (257.50 versus 338.00 mg/dL, p = 0.010) levels. Children with PCD and children without chronic diseases were both most commonly infected with Mycoplasma pneumoniae (24.6% versus 51.9%). Children with PCD had significantly more common imaging features, including mucous plugging (p = 0.042), emphysema (p = 0.007), bronchiectasis (p < 0.001), mosaic attenuation (p = 0.012), interstitial inflammation (p = 0.015), and sinusitis (p < 0.001). CONCLUSION: PCD is linked to immune system impairment, which significantly contributes to our understanding of the pathophysiology of this entity.
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AIM: To assess the role of the corneal radius of curvature (CR) in the identification of fundus tessellation in children with low myopia. METHODS: In the cross-sectional study, students aged 9-12 years from 24 primary schools in Shanghai were enrolled by cluster sampling. Participants underwent measurements including cycloplegic refraction and axial length. Fundus images and choroidal thickness were obtained by swept-source optical coherence tomography. Fundus tessellation was classified into four grades according to fundus photographs. RESULTS: A total of 1127 children with low myopia (spherical equivalence (SE) >-3.00 dioptre (D) but ≤-0.50 D) were included, with a mean age of 10.29±0.60 years and a mean SE of -1.44±0.69 D. Fundus tessellation was found in 591 (52.4%) cases (grade 1: 428, 38.0%; grade 2: 128, 11.4%; grade 3: 35, 3.1%). Choroidal thickness decreased as fundus tessellation grade increased (p trend <0.001). According to regression analysis, higher fundus tessellation grade was independently associated with larger CR (OR, 7.499; 95% CI 2.279 to 24.675, p=0.001). For those with CR >7.9 mm, along with CR, degree and proportion of fundus tessellation increased sharply. CONCLUSION: Fundus tessellation existed in more than half of children with low myopia. Preliminary fundus photography conducted in children with low myopia with large CR would be necessary and beneficial to the early management of myopic fundus changes. Trial registration number NCT02980445.
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Miopia , Rádio (Anatomia) , Criança , Humanos , China , Estudos Transversais , Fundo de Olho , Miopia/diagnóstico , Refração Ocular , Tomografia de Coerência Óptica/métodosRESUMO
BACKGROUND: Vision-dependent mechanisms play a role in myopia progression in childhood. Thus, we investigated the distribution of ocular and corneal higher-order aberrations (HOAs) in highly myopic Chinese children and adolescents and the relationship between HOA components and 1-year axial eye growth. METHODS: Baseline cycloplegic ocular and corneal HOAs, axial length (AL), spherical equivalent (SE), astigmatism and interpupillary distance (IPD) were determined for the right eyes of 458 highly myopic (SE ≤-5.0D) subjects. HOAs were compared among baseline age groups (≤12 years, 13-15 years and 16-18 years). Ninety-nine subjects completed the 1-year follow-up. Linear mixed model analyses were applied to determine the association between HOA components, other known confounding variables (age, gender, SE, astigmatism and IPD) and axial growth. A comparison with data from an early study of moderate myopia were conducted. RESULTS: Almost all ocular HOAs and few corneal HOAs exhibited significant differences between different age groups (all p<0.05). After 1 year, only ocular HOA components was significantly negative associated with a longer AL, including secondary horizontal comatic aberration (p=0.019), primary spherical aberration (p<0.001) and spherical HOA (p=0.026). Comparing with the moderate myopia data, the association of comatic aberration with AL growth was only found in high myopia. CONCLUSION: In highly myopic children and adolescents, lower levels of annual ocular secondary horizontal comatic aberration changes, besides spherical aberrations, were associated with axial elongation. This suggests that ocular HOA plays a potential role in refractive development in high myopia.
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Astigmatismo , Aberrações de Frente de Onda da Córnea , Miopia , Humanos , Criança , Adolescente , Aberrações de Frente de Onda da Córnea/diagnóstico , Miopia/diagnóstico , Refração Ocular , CórneaRESUMO
Currently, mechanical and chemical damage is the main way to carry out weed control. The use of chlorophyll fluorescence (CF) technology to nondestructively monitor the stress physiological state of weeds is significant to reveal the damage mechanism of mechanical and chemical stresses as well as complex stresses. Under simulated real field environmental conditions, different species and leaf age weeds (Digitaria sanguinalis 2-5 leaf age, and Erigeron canadensis 5-10 leaf age) were subjected to experimental treatments for 1-7 days, and fluorescence parameters were measured every 24 h using a chlorophyll fluorometer. The aim of this study was to investigate the changes in CF parameters of different species of weeds (Digitaria sanguinalis, Erigeron canadensis) at their different stress sites under chemical, mechanical and their combined stresses. The results showed that when weeds (Digitaria sanguinalis and Erigeron canadensis) were chemically stressed in different parts, their leaf back parts were the most severely stressed after 7 days, with photosynthetic inhibition reaching R=75%. In contrast, mechanical stress differs from its changes, and after a period of its stress, each parameter recovers somewhat after 1 to 2 days of stress, with heavy mechanical stress R=11%. Complex stress had the most significant effect on CF parameters, mainly in the timing and efficiency of changes in Fv/Fm, Fq'/Fm', ETR, Rfd, NPQ and Y(NO), with R reaching 71%-73% after only 3-4 days of complex stress, and its changes in complex stress were basically consistent with the pattern of changes in its chemical stress. The results of the study will help to understand the effects of mechanical and chemical stresses and combined stresses on CF parameters of weeds and serve as a guide for efficient weed control operations and conducting weed control in the future.
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Myopic retinopathy is an important cause of irreversible vision loss and blindness. As metabolomics has recently been successfully applied in myopia research, this study sought to characterize the serum metabolic profile of myopic retinopathy in children and adolescents (4-18 years) and to develop a diagnostic model that combines clinical and metabolic features. We selected clinical and serum metabolic data from children and adolescents at different time points as the training set (n = 516) and the validation set (n = 60). All participants underwent an ophthalmologic examination. Untargeted metabolomics analysis of serum was performed. Three machine learning (ML) models were trained by combining metabolic features and conventional clinical factors that were screened for significance in discrimination. The better-performing model was validated in an independent point-in-time cohort and risk nomograms were developed. Retinopathy was present in 34.2% of participants (n = 185) in the training set, including 109 (28.61%) with mild to moderate myopia. A total of 27 metabolites showed significant variation between groups. After combining Lasso and random forest (RF), 12 modelled metabolites (mainly those involved in energy metabolism) were screened. Both the logistic regression and extreme Gradient Boosting (XGBoost) algorithms showed good discriminatory ability. In the time-validation cohort, logistic regression (AUC 0.842, 95% CI 0.724-0.96) and XGBoost (AUC 0.897, 95% CI 0.807-0.986) also showed good prediction accuracy and had well-fitted calibration curves. Three clinical characteristic coefficients remained significant in the multivariate joint model (p < 0.05), as did 8/12 metabolic characteristic coefficients. Myopic retinopathy may have abnormal energy metabolism. Machine learning models based on metabolic profiles and clinical data demonstrate good predictive performance and facilitate the development of individual interventions for myopia in children and adolescents.