Parental awareness on myopia prevention and control among 350 children

AIM:To understand the current situation of parental perspectives,knowledge,and practices concerning myopia prevention and control for both pre-and school-aged children.METHODS:This study was a cross-sectional survey that involved children aged 0 to 15y and their parents.Participants were required to respond to an online questionnaire by scanning a quick response(QR)code.The questionnaire consisted of 25 tick-box questions and was open to response from December 22,2022,to January 5,2023.The dioptric traits of the children,the visual status and educational background of the parents,the parental perspectives towards myopia and its risks,and the parents’knowledge and practices related to myopia prevention and control were recorded and measured.The Chi-square test and binomial logistic regression were used for statistics.RESULTS:Totally 350 parents responded to the questionnaire.The prevalence and severity of myopia among the surveyed children exhibited a positive correlation with advancing age(P<0.001 and P=0.004,respectively).Nearly half of parents with myopic children considered myopia did not pose any health threat and could be effectively corrected(P<0.001).Parents who held master’s or doctoral degree demonstrated a better understanding of children’s vision standards for each age group(P=0.001),and 31.63% of them could undergo initial vision screening for their children during the age of 0 to 3y while parents with bachelor’s degree(34.04%)and below(32.43%)mainly initiated the vision examination for their children at the age of 4 to 6y(P=0.05).Parents with master’s or doctoral degree also exhibited more rational practices concerning outdoor time(P=0.048)and sleep time(P=0.044).No other significant discrepancy among the different educational groups in additional conceptions of myopia,such as hyperopia reserve,axis length,and corneal curvature alterations.Most parents preferred to employ conventional interventions,such as enhancing indoor lighting condition(80.00%)and ensuring appropriate reading posture and distance(71.71%).CONCLUSION:The current status of parental knowledge and practices about myopia prevention and control remains outdated and deficient.The administrative department should implement efficacious and adaptable measures to enhance parental awareness and foster their commitment towards myopia prevention and control.

不同浓度阿托品滴眼液控制儿童青少年近视进展的Meta分析

目的:评估已发表的关于不同浓度的阿托品滴眼液延缓儿童青少年近视进展的有效性。方法:搜集PubMed、the Cochrane Library、Embase、中国知网、维普和万方数据库内建库至2022-05阿托品滴眼液治疗儿童青少年近视的随机对照试验(RCT)。对纳入文献采用《Cochrane干预措施系统评价手册》中偏倚风险评价工具进行质量评价;采用Review Manager 5.4软件进行Meta分析。结果:共纳入14项RCT研究,包含3946例儿童青少年受试者。Meta分析结果显示:与对照组相比,不同浓度阿托品滴眼液均可延缓儿童青少年近视进展。1%、0.5%、0.05%、0.02%、0.01%阿托品滴眼液组的眼轴增长量均低于对照组,差异均有统计学意义(MD=-0.34,95%CI:-0.39~-0.29,P<0.00001;MD=-0.51,95%CI:-0.79~-0.24,P=0.0003;MD=-0.17,95%CI:-0.30~-0.04,P=0.01;MD=-0.21,95%CI:-0.30~-0.11,P<0.0001;MD=-0.09,95%CI:-0.13~-0.05,P<0.0001)。0.1%阿托品滴眼液组眼轴增长量低于对照组,差异无统计学意义(MD=-0.50,95%CI:-1.28~0.28,P=0.21)。结论:不同浓度阿托品滴眼液均可有效延缓儿童青少年近视进展,0.01%阿托品滴眼液延缓近视进展同时不良反应发生率最低。

Experimental study on motion and mechanical characteristics of the vertical wheel in the rock-breaking process

Polycrystalline diamond compact(PDC)drill bit often performs with low ROP,short service life and poor stability under complicated and difficult to drill formations.Therefore,a vertical wheel PDC bit is proposed,which is a new drill bit technology applying an integrated unit combining the tooth wheel and the rotary shaft thereof.Besides,the experiments on motion and mechanical characteristics of the vertical wheel under the conditions of tooth shape and number of teeth,normal deflection angle of the wheel,and different cutting depth were carried out using variable parameter experimental device,and the movement,force law,and crushing specific work of vertical wheel under different experimental conditions were obtained.The comparative experiments of PDC cutting rock breaking under the conditions of parallel cutting of PDC unit and pre-damage of the wheel were also carried out,and the cutting load of PDC teeth under pre-damage conditions is between 38.72% and 70.95%lower than that of parallel cutting was obtained.Finally,a comparative experiment of indoor drilling between vertical wheel PDC bit and conventional PDC bit was carried out.Results show than when drilling in gravel rock,under the same WOB,the torque response of vertical wheel PDC bit is equivalent to that of the PDC bit,while the ROP of vertical wheel PDC bit is 22.94%-53.33% higher than that of conventional PDC bit,and the threedimensional acceleration of the vertical wheel PDC bit is 19.17%-76.23% of that of the PDC bit.The experimental results contribute to a better understanding of vertical wheels and provide technical support for their use in PDC bits.

Fracture propagation and induced strain response during supercritical CO_(2)jet fracturing

To investigate fracture generation and strain variation during SC-CO_(2)(supercritical carbon dioxide)jet fracturing,the model of induced strain is established and the experiments are comprehensively studied.The influence factors are comprehensively explored,such as jet pressure,ambient pressure,etc.With the increasing jet pressure,the fracture morphology changes from parallel cracks to oblique cracks.Both the mass loss of specimen and CO_(2) absorption increase significantly,and the growth rate and minimum value of strain also rise exponentially.Under a high ambient pressure of 8.0 MPa,the main fractures mostly propagated from the surface to the bottom surface of the specimen.The maximum strain and the stable duration under higher ambient pressure are 1.5 times and 10 times,respectively,of the case under the ambient pressure of 5.0 MPa.The comparison shows that the optimal jet distance is 5-7 times the nozzle diameter,resulting in massive mass loss,large CO_(2)absorption,and peak strain.Moreover,the nonlinear variation of strain curve during jet pressurization is related to the type of rock and ambient pressure.These studies clearly show the relationship between the fracture morphology and induced strain,which are crucial for SC-CO_(2)fracturing in shale gas reservoirs.

Association of T lymphocyte subset counts with the clinical features of colorectal cancer

Background:Colorectal cancer(CRC)is a common gastrointestinal malignancy.The T lymphocyte subsets are important in the develop-ment,invasion and metastasis of tumors,including CRC.Nevertheless,limited research has explored the relationship between T cell subpopu-lations and the clinical characteristics of CRC.This study compared the T lymphocyte subsets in patients with CRC and healthy individuals,and assessed the relationship between these values and clinical characteristics.Methods:Peripheral blood was collected from 100 patients with CRC and 54 healthy individuals.The numbers of CD3^(+)T,CD4^(+)T,and CD8^(+)T lymphocytes,NK cells,and the CD4^(+)T/CD8^(+)T ratio in peripheral blood were measured using flow cytometry,and were compared between CRC patients and healthy individuals.Spearman's correlation analysis was performed to investigate the relationship between the T lymphocyte subsets in patients diagnosed with CRC and the levels of carcinoembryonic antigen(CEA)and thymidine kinase 1(TK1).Receiver operating characteristic(ROC)curves were utilized to evaluate the potential utility of the T lymphocyte counts in predicting lymph node metastasis,vas-cular infiltration,and high Ki-67 expression.Results:The CRC patients had lower counts of CD3^(+)T,CD4^(+)T,and CD8^(+)T lymphocytes compared to the healthy population(P<0.05).However,no significant differences were observed in the CD4^(+)/CD8^(+)ratio or NK cells(P>0.05).Notably,the CD3^(+)T,CD4^(+)T,and CD8^(+)T lym-phocyte counts were higher in patients with stageⅠ-Ⅱdisease,no lymph node metastasis,no vascular invasion,and low Ki-67 expression than in those with stageⅢ,lymph node metastasis,vascular invasion,and high Ki-67 expression(P<0.05).There was a negative association be-tween the CD3^(+)T,CD4^(+)T,and CD8^(+)T lymphocyte counts and CEA and TK1 levels in patients with CRC.The ROC curves demonstrated that CD3^(+)T,CD4^(+)T,and CD8^(+)T lymphocyte counts had significant predictive value for lymph node metastasis,vascular infiltration,and high Ki-67 expression.Conclusions:The peripheral blood CD3^(+)T,CD4^(+)T,and CD8^(+)T lymphocyte counts are related to the clinical traits of patients with CRC and can predict the prognosis of the disease.