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Abstract The mechanism of the difference in bacterial community composition caused by environmental factors in the underground coal mine is unclear. In order to reveal the influence of coal mining activities on the characteristics of bacterial community structure in coal seam, 16S rRNA gene amplicon sequencing technology was used to determine the species abundance, biodiversity, and gene abundance of bacterial community in a coal mine in Shanxi Province, and the environmental factors such as metal elements, non-metal elements, pH value, and gas concentration of coal samples were determined. The results showed that environmental factors and bacterial communities had obvious regional characteristics. Mining activities greatly affected the α diversity of bacterial communities, mining working face > main airway > roadway roof > unexposed coal seam > tunneling roadway. The bacterial community composition of each sample point is also very different. The main airway, roadway roof, and unexposed coal seam are dominated by Actinobacteria while the mining working face and tunneling roadway are dominated by Proteobacteria. Among the gene abundances of metabolic pathways in each site, Citrate cycle had the greatest difference, followed by glycine, serine and threonine metabolism, and oxidative phosphorylation and methane metabolism had little difference. RDA analysis showed that the environmental factors affecting the bacterial community were mainly cadmium, oxygen, hydrogen, and gas content. CCA analysis divided the bacterial community into three categories. Degradation functional bacteria are located in mining working face, bacteria that tolerate poor environments are located in main airway and tunneling roadway, and human pathogens are mostly located in roadway roof and unexposed coal seam. The research results would provide support for realizing green and safe mining in coal mines.

Abstract 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

Abstract To develop and validate a machine learning based algorithm to estimate physical activity (PA) intensity using the smartwatch with the capacity to record PA and determine outdoor state. Two groups of participants, including 24 adults (13 males) and 18 children (9 boys), completed a sequential activity trial. During each trial, participants wore a smartwatch, and energy expenditure was measured using indirect calorimetry as gold standard. The support vector machine algorithm and the least squares regression model were applied for the metabolic equivalent (MET) estimation using raw data derived from the smartwatch. Exercise intensity was categorized based on MET values into sedentary activity (SED), light activity (LPA), moderate activity (MPA), and vigorous activity (VPA). The classification accuracy was evaluated using area under the ROC curve (AUC). The METs estimation accuracy were assessed via the mean absolute error (MAE), the correlation coefficient, Bland–Altman plots, and intraclass correlation (ICC). A total of 24 adults aged 21–34 years and 18 children aged 9–13 years participated in the study, yielding 1790 and 1246 data points for adults and children respectively for model building and validation. For adults, the AUC for classifying SED, MVPA, and VPA were 0.96, 0.88, and 0.86, respectively. The MAE between true METs and estimated METs was 0.75 METs. The correlation coefficient and ICC were 0.87 (p

BackgroundThe World Health Organization declared mpox an international public health emergency. Since January 1, 2022, China has been ranked among the top 10 countries most affected by the mpox outbreak globally. However, there is a lack of spatial epidemiological studies on mpox, which are crucial for accurately mapping the spatial distribution and clustering of the disease. ObjectiveThis study aims to provide geographically accurate visual evidence to determine priority areas for mpox prevention and control. MethodsLocally confirmed mpox cases were collected between June and November 2023 from 31 provinces of mainland China excluding Taiwan, Macao, and Hong Kong. Spatiotemporal epidemiological analyses, including spatial autocorrelation and regression analyses, were conducted to identify the spatiotemporal characteristics and clustering patterns of mpox attack rate and its spatial relationship with sociodemographic and socioeconomic factors. ResultsFrom June to November 2023, a total of 1610 locally confirmed mpox cases were reported in 30 provinces in mainland China, resulting in an attack rate of 11.40 per 10 million people. Global spatial autocorrelation analysis showed that in July (Moran I=0.0938; P=.08), August (Moran I=0.1276; P=.08), and September (Moran I=0.0934; P=.07), the attack rates of mpox exhibited a clustered pattern and positive spatial autocorrelation. The Getis-Ord Gi* statistics identified hot spots of mpox attack rates in Beijing, Tianjin, Shanghai, Jiangsu, and Hainan. Beijing and Tianjin were consistent hot spots from June to October. No cold spots with low mpox attack rates were detected by the Getis-Ord Gi* statistics. Local Moran I statistics identified a high-high (HH) clustering of mpox attack rates in Guangdong, Beijing, and Tianjin. Guangdong province consistently exhibited HH clustering from June to November, while Beijing and Tianjin were identified as HH clusters from July to September. Low-low clusters were mainly located in Inner Mongolia, Xinjiang, Xizang, Qinghai, and Gansu. Ordinary least squares regression models showed that the cumulative mpox attack rates were significantly and positively associated with the proportion of the urban population (t0.05/2,1=2.4041 P=.02), per capita gross domestic product (t0.05/2,1=2.6955; P=.01), per capita disposable income (t0.05/2,1=2.8303; P=.008), per capita consumption expenditure (PCCE; t0.05/2,1=2.7452; P=.01), and PCCE for health care (t0.05/2,1=2.5924; P=.01). The geographically weighted regression models indicated a positive association and spatial heterogeneity between cumulative mpox attack rates and the proportion of the urban population, per capita gross domestic product, per capita disposable income, and PCCE, with high R2 values in north and northeast China. ConclusionsHot spots and HH clustering of mpox attack rates identified by local spatial autocorrelation analysis should be considered key areas for precision prevention and control of mpox. Specifically, Guangdong, Beijing, and Tianjin provinces should be prioritized for mpox prevention and control. These findings provide geographically precise and visualized evidence to assist in identifying key areas for targeted prevention and control.

Selenium (Se) is an essential trace element known for its significant role in maintaining human health and mitigating disease progression. Selenium and its compounds exhibit high selective cytotoxicity against tumor cells. However, their anti-cervical cancer (CC) effects and underlying mechanisms have not been fully explored. This study found that sodium selenite (SS) inhibits the viability of HeLa and SiHa cells in a dose- and time-dependent manner. Intraperitoneal injection of 3 and 6 mg/kg SS for 14 days in female nude mice significantly inhibited the growth of HeLa cell xenografts without evident hepatotoxicity or nephrotoxicity. RNA sequencing results indicated that the AMP-activated protein kinase (AMPK), Forkhead box protein O (FOXO), and apoptosis signaling pathways are key regulatory pathways in SS’s anti-CC effects, and SS’s inhibition of HeLa cell proliferation may be related to autophagy and ROS-induced apoptosis. Further research has revealed that SS induces cell autophagy and apoptosis through the AMPK/mTOR/FOXO3a pathway, characterized by the upregulation of p-AMPK/AMPK, FOXO3a, LC3-II, cleaved-caspase3, and cleaved-PARP and the downregulation of p-mTOR/mTOR and p62. Additionally, SS impaired mitochondrial function, including decreased mitochondrial membrane potential, mitochondrial Ca2+ overload, and accumulation of mitochondrial reactive oxygen species (mtROS). Pretreatment with Mitoquinone mesylate (Mito Q) and compound C partially reversed SS-induced apoptosis, autophagy, and proliferation inhibition. Pretreatment with 3-methyladenine (3-MA) enhances SS-induced apoptosis and proliferation inhibition in HeLa cells but reverses these effects in SiHa cells. In summary, SS induces apoptosis, autophagy, and proliferation inhibition in HeLa and SiHa cells through the activation of the AMPK/mTOR/FOXO3a signaling pathway via mtROS. Autophagy activation may be a major risk factor for SS-induced apoptosis in SiHa cells but can protect HeLa cells from SS-induced apoptosis. These findings provide new evidence for understanding the molecular mechanisms underlying SS in potential new drug development for CC.

Abstract Introduction Orthokeratology (OK) and low-concentration atropine are recommended approaches for controlling myopia. However, children with younger age and lower myopia are more likely to experience rapid axial progression during OK or atropine monotreatment. This study aimed to assess the efficacy of OK combined with low-concentration atropine for myopia control in children over 24 months and to determine whether the effect was sustainable. Methods In this retrospective study, we reviewed medical records of baseline and follow-up visits from children (7–14 years) applying OK for myopia control. Sixty-eight children receiving monoorthokeratology treatment (OK group) and 68 children who received 0.01% atropine in combination with orthokeratology simultaneously (AOK group) were included. A series of ophthalmic tests at baseline were conducted, and axial length (AL) was measured every 6 months. The comparison of AL change at different visits between the two groups was performed by repeated measures multivariate analyses of variance (RM–MANOVA). Results There were no significant differences in baseline characters between the two groups (p > 0.05). The AL significantly increased over time in both groups (all p

IntroductionRice black-streaked dwarf virus disease (RBSDVD) is one of the most destructive rice viral diseases, leading to severe yield losses in rice production. However, little is known about the yield-related components associated with the disease and no resistance cultivars have been successfully used in rice breeding.MethodsSeven rice cultivars were analyzed in this study, including six commercial rice varieties and a new line Zhongjian No. 201 (ZJ201) containing the resistance gene OsAP47. Resistance levels of these cultivars were evaluated by artificial inoculation and yield components were collected, including panicle length (PL), spikelets per panicle (SPP), ripened grains per panicle (RGPP), as well as panicles per square meter (PPSM) and 1000-grain weight (TGW). Seed setting rate (SSR) were calculated with the data of SPP and RGPP.Results and discussionThe results showed that ZJ201 displayed the highest resistance level and most of the commercial rice cultivars exhibited susceptible to RBSDVD. Yields of all the rice cultivars were significantly declined except ZJ201 and yield losses produced by RBSDVD were mainly due to the reduction of PL, SPP, RGPP, and TGW, suggesting that developments of these traits are associated with RBSDV infection. Resistant rice cultivar could reduce yield losses by maintaining normal development of these traits. Significant correlations were identified between resistance levels and the yield components except SSR and PPSM. The results provided useful clues for understanding the mechanisms of RBSDV invasion and its effect on rice production. ZJ201 was demonstrated as a resistance material that could be used in rice breeding.

Abstract Irrigation with mine water not only improves water resource utilization rates and alleviates water shortages but can also promote crop growth and yields. However, long-term irrigation with mine water can significantly change the physicochemical properties of soil due to its unique mineral content. In this study, two groups of experiments were conducted (pot experiments and soilless cultivation) using mine water from the Fushun mining area to explore its effects on the physiological and photosynthetic characteristics of ryegrass, as well as soil properties. Mine water irrigation inhibited all of the indicators evaluated in this study, whereas a mixture of clean water and mine water had a stimulatory effect. Interestingly, this stimulatory effect was weakened as the proportion of mine water increased but reached its maximum when the ratio was 2:1. Moreover, the inhibitory effect of the irrigation water was weakened as the proportion of clean water increased. The contents of K+, Na+, Ca2+ and Mg2+ in soil were higher than those in the soil matrix, and the content of the nutrient elements N, P and K, and metal cations increased gradually as the mine water ratio increased, and the electrical conductivity increased significantly. Moreover, the pH of the soil decreased steadily (i.e. acidity increased) with increased soil salinity. Our findings indicated that a mixture of mine water from Fushun mining area and clean water at a 1:2 ratio could improve the physiological, growth, and photosynthetic characteristics of ryegrass by enhancing soil quality. Our study thus provides an experimental precedent for the utilization of mine water in ecological restoration and agricultural irrigation, and could therefore serve as a basis for the development of novel strategies for environmental restoration and the utilization of water resources.

Abstract Purpose To investigate the difference of spherical equivalent (SE) and pupil diameter in adult patients with intermittent exotropia (IXT) under various viewing conditions before and after surgery. Methods We retrospectively analyzed the medical records of 23 adult patients who underwent a surgery for IXT. The angle of deviation was measured by the prism and alternative cover test. Refractive error and pupil diameter were measured using the Grand Seiko WAM-5500 open-field autorefractor under binocular and monocular viewing conditions when patients stared at distance (6 m) and near (33 cm). Regression analyses were performed between accommodative load and the angle of deviation. Results Twenty-three patients (10 males, 13 females) with a mean age of 31.17±8.95 years, of whom 13 (56.5%) had the right eye as the dominant eye. The mean angle of deviation at near and at distance was 69.57±26.37 and 65.43±28.92 prism diopters respectively. There were no significant differences in accommodative response and pupil diameter between the dominant and non-dominant eyes. SE decreased when patients changed from monocular to binocular viewing, and from distant to near viewing (all P< 0.05), so as the pupil diameter (all P< 0.001). During binocular, not monocular viewing, SE was significantly greater after operation than it was before operation (P< 0.001). Accommodative load and pupillary constriction narrowed (p< 0.001) after the operation. Linear regression analysis showed a correlation between the angle of deviation at distance and accommodative load at distance (r2=0.278, p=0.010) and at near (r2=0.332, p=0.005). Conclusion In order to maintain ocular alignment, patients with IXT suffer a large accommodative load, which is related to the angle of deviation. Surgery helps eliminating extra accommodation.

The first fractured shale gas well of China was constructed in 2010. After 10 years of development, China has become the second country that possesses the core technology of shale gas development around the world, realized the shale gas fracturing techniques from zero to one and from lagging to partially leading, and constructed the fracturing theory and technology system suitable for middle–shallow marine shale gas exploitation. In order to provide beneficial guidance for the efficient exploitation of shale gas in China in the future, this paper comprehensively reviews development history and status of domestic fundamental theories, optimized design methods, fluid systems, tools and technologies of shale gas fracturing and summarizes the research results in fundamental theories and optimized design methods, such as fracturing sweet-spot cognition, fracture network propagation simulation and control, rock hydration and flowback control, and SRV (stimulated reservoir volume) evaluation and characterization. The development and application of slick-water fracturing fluid system and new fracturing fluid with little or no water is discussed. The development and independent research & development level of multi-stage fracturing tools are evaluated, including drillable composite plug, soluble plug, large-diameter plug and casing cementing sleeve. The implementation situations of field technologies and processes are illustrated, including the early conventional multi-stage multi-cluster fracturing and the current “dense cluster” fracturing and temporary plugging fracturing. Based on this, the current challenges to domestic shale gas fracturing technologies are analyzed systematically, and the development direction of related technologies is forecast. In conclusion, it is necessary for China to continuously research the fracturing theories, technologies and methods suitable for domestic deep and ultra-deep marine shale gas, terrestrial shale gas and transitional shale gas to facilitate the future efficient development of shale gas in China.

Accurate phenotypic identification is the basis of research for resistance genetics and rice breeding for resistance to RBSDV disease. Obtaining rice black-streaked dwarf virus (RBSDV) viruliferous small brown planthoppers (SBPHs) with high transmission efficiency is an essential part of accurate phenotypic identification. Here, through quantifying number of RBSDV copies in infected rice plants, optimizing times of SBPHs fed on RBSDV-infected rice plants and leaf stage of rice seedlings, a method to acquire an RBSDV-carrying SBPH population more efficiently was improved. The results showed that rate of viruliferous SBPHs was significantly higher when fed on RBSDV-infected rice plants that had the copy numbers of RBSDV S10 of 3.0*104 and 1.1*104 than 8.3*102. Therefore, it is more efficient for SBPHs to acquire the virus when fed on RBSDV-infected rice plants that have copy numbers of RBSDV S10 above 1.1*104. The rate of viruliferous SBPHs were 50% and 54%, respectively, after the insects fed on RBSDV-infected rice plants for 7 and 9 days and being transferred to healthy rice seedlings for 5 and 3 days, which was significantly higher than those at other feeding times. The optimal inoculation leaf stage of rice seedlings was the 2-3-leaf stage (3 effective SBPHs per seedling for 72 h), but a high rate of viruliferous SBPHs may be suggested for inoculation of older rice seedlings.

BackgroundNo spatial analysis of hair selenium and Keshan disease (KD) on a nationwide county-level has been performed. Selenium deficiency is a recognized environmental risk factor for KD. Hair selenium is one of the recognized biomarkers of selenium nutrition. This study aimed to perform a geographically precise and visualized assessment of the achievement of KD prevention and control at the level of selenium nutrition in terms of etiology.MethodsA spatial ecological study was conducted. The hair selenium content of the residents was assayed using an atomic fluorescence spectrometer. The spatial analysis was performed using ArcGIS.ResultsThe median of the hair selenium levels of the 3,028 participants in the 1,174 counties was 0.38 mg/kg, and the content of inhabitants in KD endemic counties was significantly lower than that in KD non-endemic counties (0.34 vs. 0.39 mg/kg, z = −10.03, P < 0.0001). The proportion of Se-deficient and Se-marginal counties in KD endemic counties was significantly higher than that in KD non-endemic counties (59.4 vs. 29.0%, z = −7.45, P < 0.0001). The global autocorrelation analysis was not statistically significant (Moran's I = 0.0005, P = 0.68). Local autocorrelation analysis identified 174 low-low clusters of hair selenium levels, 83 (47.7%) of which are KD endemic counties located in KD endemic provinces of Henan, Gansu, Shaanxi, Inner Mongolia, Jilin, and Heilongjiang. The hair selenium featured a positive correlation with per capita GDP (rs = 0.20, P < 0.0001).ConclusionThe median of the hair selenium levels of inhabitants living in KD endemic counties was significantly lower than that in KD non-endemic counties. All the 83 KD endemic counties with low-low clusters of hair selenium levels should be prioritized in KD precision prevention and control. These findings are geographically precise and visualized evidence of the assessment of the effectiveness of KD prevention and control at the level of selenium nutrition in terms of etiology.

Objectives: Few researchers have studied the national prevalence of Keshan disease (KD) in China using spatial epidemiological methods. This study aimed to provide geographically precise and visualized evidence for the strategies for KD prevention and control. Methods: We surveyed and analyzed 237,000 people in 280 out of 328 KD-endemic counties (85.4%) in mainland China using a design of key investigation based on case-searching in 2015–2016. ArcGIS version 9.0 was used for spatial autocorrelation analysis, spatial interpolation analysis and spatial regression analysis. Results: Global autocorrelation analysis showed that global clustering of latent Keshan disease (LKD) prevalence was noted (Moran’s 'I' = 0.22, 'Z' = 7.06, and 'P' < 0.0001), no global clustering of chronic Keshan disease (CKD) prevalence (Moran’s 'I' = 0.03, 'Z' = 1.10, and 'P' = 0.27) was observed. Spatial regression analysis showed that LKD prevalence was negatively correlated with per capita disposable income ('t' = −4.36, 'P' < 0.0001). Local autocorrelation analysis at the county level effectively identified the cluster areas of LKD prevalence in the provinces of Shaanxi, Gansu, Shanxi, Inner Mongolia, and Jilin. The high-high cluster areas should be given priority for precision prevention and control of Keshan disease. Conclusions: This spatial epidemiological study revealed that LKD prevention and control should be strengthened in areas with high values of clustering. Our findings provided spatially, geographically precise and visualized evidence for prioritizing KD prevention and control.

Rice viral diseases adversely affect crop yield and quality. Most rice viruses are transmitted through insect vectors. However, the traditional whole-plant inoculation method cannot control the initial inoculation site in rice plants because the insect feeding sites in plants are random. To solve this problem, we established a determined-part inoculation approach in this study that restricted the insect feeding sites to specific parts of the rice plant. Rice stripe virus (RSV) was used as the model virus and was inoculated at the bottom of the stem using our method. Quantitative real-time PCR and Western blot analyses detected RSV only present at the bottom of the Nipponbare (NPB) stem at 1 day post-inoculation (dpi), indicating that our method successfully controlled the inoculation site. With time, RSV gradually moved from the bottom of the stem to the leaf in NPB rice plants, indicating that systemic viral spread can also be monitored using this method. In addition, a cultivar resistant to RSV, Zhendao 88 (ZD88), was inoculated using this method. We found that RSV accumulation in ZD88 was significantly lower than in NPB. Additionally, the expression level of the resistant gene STV11 in ZD88 was highly induced at the initial invasion stage of RSV (1 dpi) at the inoculation site, whereas it remained relatively stable at non-inoculated sites. This finding indicated that STV11 directly responded to RSV invasion to inhibit virus accumulation at the invasion site. We also proved that this approach is suitable for other rice viruses, such as Rice black-streaked dwarf virus (RBSDV). Interestingly, we determined that systemic infection with RSV was faster than that with RBSDV in NPB, which was consistent with findings in field trails. In summary, this approach is suitable for characterizing the viral infection process in rice plants, comparing the local viral accumulation and spread among different cultivars, analyzing the spatiotemporal expression pattern of resistance-associated genes, and monitoring the infection rate for different viruses.

Background This research aims to generate normative values of hyperopia reserve and refractive progression as effective tools to estimate the risk of myopia. Methods A 1-year follow-up study was conducted among Chinese children and adolescents aged 3-16 years selected from schools and kinder gardens using cluster sampling. All participants underwent examinations including visual acuity, axial length and cycloplegic autorefraction (1% cyclopentolate). Percentiles of spherical equivalent (SE) were calculated using Lambda-Mu-Sigma (LMS) method. Age-specific refractive progression and hyperopia reserve were determined by backward calculation. Results Of 3118 participants, 1702 (54.6%) were boys with a mean baseline age of 7.30 years. The 50th percentile of SE estimated by LMS decreased from 1.04 D at 3 years to -2.04 D at 16 years in boys, while from 1.29 D to -2.81 D in girls. The 1-year refractive progression of myopes (0.81 D) was greater than that of non-myopes (0.51 D). The normative value of hyperopia reserve was 2.64 (range: 2.40 D-2.88 D) at 3 years and -0.35 (range: -0.50 to -0.17) D at 16 years, with the maximum progression of 0.35 D at the age of 6 years. Conclusion Age-specific normative values of hyperopia reserve and yearly myopic shift in children and adolescents aged 3-16 years were provided, helping identify and monitor myopia and giving prevention in advance. [ABSTRACT FROM AUTHOR]

Abstract Unequal outcomes resulting from urbanization can pose a significant challenge to sustainable development. Vehicles are an important urbanization dimension as a critical component of urban infrastructure by providing mobility and accessibility to social services. China’s vehicle ownership (referred to as in-use vehicle stocks) has been growing quickly since 2000, but its per capita stocks are still much lower than that in developed economies. This raises the question of whether and when China’s vehicle stocks will reach a peak level close to that in the developed countries. By analyzing vehicle stocks in 283 Chinese cities during 2001–2018, we have the following findings: (1) vehicle stocks are predominantly distributed in northern and eastern coastal cities and provincial capital cities; (2) inequality in vehicle ownership rates between cities shows a declining trend at both national and region scales; (3) the growth of vehicle ownership rates follows an S-shape curve and most cities are still at the early stage of motorization; (4) China is likely to have a lower saturation level of vehicle ownership rate. These results could help to accurately forecast future vehicle demand in China, estimate the resulting environmental impacts, and explore strategies to achieve carbon neutrality in transportation.

Purpose To develop age-specific and gender-specific reference percentile charts for axial length (AL) and AL/corneal radius of curvature (AL/CR) and, to use percentiles to determine probability of myopia and estimate refractive error (RE). Methods Analysis of AL, cycloplegic RE and CR of 14 127 Chinese participants aged 4-18 years from 3 studies. AL and AL/CR percentiles estimated using Lambda-Mu-Sigma method and compared for agreement using intraclass correlation (ICC). Logistic regression was used to model risk of myopia based on age, gender, AL and AL/CR percentiles. Accuracy of AL progression and RE estimated using percentiles was validated using an independent sample of 5742 eyes of children aged 7-10 years. Results Age-specific and gender-specific AL and AL/CR (3rd, 5th, 10th, 25th, 50th, 75th, 90th and 95th) percentiles are presented. Concordance between AL and AL/CR percentiles improved with age (0.13 at 4 years to >0.75 from 13 years) and a year-to-year change was observed for all except <10th percentile from 15 years. Increasing age, AL and AL/CR was associated with a more myopic RE (r2=0.45,0.70 and 0.83, respectively). The sensitivity and specificity of the model to estimate probability of myopia was 86.0% and 84.5%, respectively. Estimation of 1-year change in AL using percentiles correlated highly with actual AL (ICC=0.98). Concordance of estimated to actual RE was high (ICC=0.80) and within ±0.50D and ±1.0D of actual RE for 47.4% and 78.9% of eyes, respectively. Conclusion Age-specific and gender-specific AL and AL/CR percentiles provide reference data, aid in identifying and monitoring individuals at risk of myopia and have utility in screening for myopia. AL/CR percentiles were more accurate in estimating probability of myopia in younger children. [ABSTRACT FROM AUTHOR]