The principle of planc-to-plane perpendicularity measuring with coordinate measuring machine （CMM） is described and the main factors that influence the measuring precision are analyzed. The minimum condition method ...The principle of planc-to-plane perpendicularity measuring with coordinate measuring machine （CMM） is described and the main factors that influence the measuring precision are analyzed. The minimum condition method is adopted to eliminate the fitting error of the datum plane. In order to diminish the length error of the object plane, the tactics of measuring some part of the plane and then scale to the whole plane is employed. With large quantity of measuring experiments on fiat plates, the most appropriate number of points in measuring a plane is determined to reduce the sampling error.展开更多
Purpose:A cross-sectional study was conducted to explore the relationship between refractive error and ocular biometrics in children from the Guangzhou twin eye study.Methods:.Twin participants aged 7-15 years were se...Purpose:A cross-sectional study was conducted to explore the relationship between refractive error and ocular biometrics in children from the Guangzhou twin eye study.Methods:.Twin participants aged 7-15 years were selected from Guangzhou Twin Eye Study..Ocular examinations included visual acuity measurement, ocular motility evaluation, autorefraction under cycloplegia, and anterior segment, media, and fundus examination...Axial length(AL),..anterior cham ber depth(ACD), and corneal curvature radius were measured using partial coherence laser interferometry. A multivariate linear regression model was used for statistical analysis.Results:.Twin children from Guangzhou city showed a decreased spherical equivalent with age,.whereas both AL and ACD were increased and corneal curvature radius remained unchanged. When adjusted by age and gender, the data from77% of twins presenting with spherical equivalent changes indicated that these were caused by predictable variables.(R2=0.77, P<0.001). Primary factors affecting children's refraction included axial length(β=-0.97,P<0.001), ACD(β=0.33,P<0.001), and curvature radius(β=2.10,P<0.001). Girls had a higher tendency for myopic status than did boys(β=-0.26,P<0.001)..Age exerted no effect upon the changes in refraction(β=-0.01, P=0.25).Conclusion:.Refraction is correlated with ocular biometrics.Refractive status is largely determined by axial length as the major factor.展开更多
AIM: To examine the refractive prediction error in high myopic eyes after phacovitrectomy.METHODS: This retrospective comparative case series included 91 eyes(18 high myopic eyes and 73 non-high myopic eyes) of 91 pat...AIM: To examine the refractive prediction error in high myopic eyes after phacovitrectomy.METHODS: This retrospective comparative case series included 91 eyes(18 high myopic eyes and 73 non-high myopic eyes) of 91 patients who underwent successful phacovitrectomy(phacoemulsification, intraocular lens implantation, and pars plana vitrectomy). The high myopic eyes were defined as the eye with more than 26.0mm of axial length. The postoperative prediction error of mean error and mean absolute error were evaluated at4 mo postoperatively. Axial length and keratometry measurement were performed preoperatively and 4mo postoperatively using the IOL Master.RESULTS: The refractive outcome after phacovitrectomy showed significantly greater myopic shift in the high myopic eyes [-1.08 ±0.87 diopters(D)] than that in the non-high myopic eyes(-0.43 ±0.63 D, P =0.004). Axial length and keratometric value in the high myopic eyes were significantly increased(P =0.043, 0.037 respectively),whereas those in the non-high myopic group were not significantly increased(P =0.135, 0.347 respectively). The change of the axial length in the myopic eye(0.46±0.28 mm)was greater than that in the non- high myopic eye(0.11 ± 0.34 mm; P 【0.001).CONCLUSION: High myopic eyes showed more myopic shift than non-high myopic eyes after phacovitrectomy.The cause of myopic shift in high myopic eyes seems tobe attributed to actual elongation of the axial length in high myopia.展开更多
This paper introduces a high precision 7m laser measuring instrument developedby the anthors and its operating principle,and systematically analyses the errors havinginfluence on the performance of the measuring instr...This paper introduces a high precision 7m laser measuring instrument developedby the anthors and its operating principle,and systematically analyses the errors havinginfluence on the performance of the measuring instrument.Error analysis and actualverification indicate that all the characteristics reached or exceeded the original designspecifications.展开更多
Reversible variable length codes (RVLCs) have received much attention due to their excellent error resilient capabilities. In this paper, a novel construction algorithm for symmetrical RVLC is proposed which is indepe...Reversible variable length codes (RVLCs) have received much attention due to their excellent error resilient capabilities. In this paper, a novel construction algorithm for symmetrical RVLC is proposed which is independent of the Huffman code. The proposed algorithm's codeword assignment is only based on symbol occurrence probability. It has many advantages over symmetrical construction algorithms available for easy realization and better code performance. In addition, the proposed algorithm simplifies the codeword selection mechanism dramatically.展开更多
<strong>Background: </strong>Population ageing is a worldwide phenomenon. It is common for older adults to develop multiple age-related illnesses and the prevalence of multimorbidity increases substantiall...<strong>Background: </strong>Population ageing is a worldwide phenomenon. It is common for older adults to develop multiple age-related illnesses and the prevalence of multimorbidity increases substantially with age. Multimorbid adults are frequently treated with several concurrent medications and the regimen may be complex requiring multiple steps in the preparation of a medication prior to its administration. Polypharmacy is a concerning trend and older adults have a 100% risk of experiencing adverse drug events when taking ten or more medications concurrently. Discharge summaries communicating the number of medications, changes made to medication regimens during hospitalisations and the requirement for ongoing monitoring in the community are often incomplete. The aim of this study was to investigate contributing factors to medication-related hospitalisation, length of stay or readmission in older community-dwelling persons and examine the quality of discharge summaries. <strong>Methods: </strong>Descriptive and correlational analyses of demographic, clinical, admission, readmission, length of stay and medication variables were examined in Australia in 2016-2018. Discharge summaries were analysed for completeness, timeliness and interprofessional communication. <strong>Results: </strong>There were 295 participants, mean age 80 years, 55% were female, taking an average of 11 prescribed medications and with a mean Medication Regimen Complexity Index score of 34. Medication errors that were unrecognised at the time of hospitalisation were present in 19% of the sample. Factors associated with medication error were older age and a longer median length of stay. Fewer than 52% of these older patients had detailed discharge summaries. <strong>Conclusion: </strong>The prevalence of polypharmacy and medication regimen complexity at admission was high. A high proportion of older adults on medical units may have unrecognised medication errors impacting their admission. Medical discharge summaries are inadequately addressing this issue for patients returning to the care of their family physician.展开更多
基金sponsored by the Special Research Fund for Young Teachers of Universities in Shanghai under Grant No.gjd-07048
文摘The principle of planc-to-plane perpendicularity measuring with coordinate measuring machine （CMM） is described and the main factors that influence the measuring precision are analyzed. The minimum condition method is adopted to eliminate the fitting error of the datum plane. In order to diminish the length error of the object plane, the tactics of measuring some part of the plane and then scale to the whole plane is employed. With large quantity of measuring experiments on fiat plates, the most appropriate number of points in measuring a plane is determined to reduce the sampling error.
基金Natural Science Foundation of China(No.81271037)
文摘Purpose:A cross-sectional study was conducted to explore the relationship between refractive error and ocular biometrics in children from the Guangzhou twin eye study.Methods:.Twin participants aged 7-15 years were selected from Guangzhou Twin Eye Study..Ocular examinations included visual acuity measurement, ocular motility evaluation, autorefraction under cycloplegia, and anterior segment, media, and fundus examination...Axial length(AL),..anterior cham ber depth(ACD), and corneal curvature radius were measured using partial coherence laser interferometry. A multivariate linear regression model was used for statistical analysis.Results:.Twin children from Guangzhou city showed a decreased spherical equivalent with age,.whereas both AL and ACD were increased and corneal curvature radius remained unchanged. When adjusted by age and gender, the data from77% of twins presenting with spherical equivalent changes indicated that these were caused by predictable variables.(R2=0.77, P<0.001). Primary factors affecting children's refraction included axial length(β=-0.97,P<0.001), ACD(β=0.33,P<0.001), and curvature radius(β=2.10,P<0.001). Girls had a higher tendency for myopic status than did boys(β=-0.26,P<0.001)..Age exerted no effect upon the changes in refraction(β=-0.01, P=0.25).Conclusion:.Refraction is correlated with ocular biometrics.Refractive status is largely determined by axial length as the major factor.
文摘AIM: To examine the refractive prediction error in high myopic eyes after phacovitrectomy.METHODS: This retrospective comparative case series included 91 eyes(18 high myopic eyes and 73 non-high myopic eyes) of 91 patients who underwent successful phacovitrectomy(phacoemulsification, intraocular lens implantation, and pars plana vitrectomy). The high myopic eyes were defined as the eye with more than 26.0mm of axial length. The postoperative prediction error of mean error and mean absolute error were evaluated at4 mo postoperatively. Axial length and keratometry measurement were performed preoperatively and 4mo postoperatively using the IOL Master.RESULTS: The refractive outcome after phacovitrectomy showed significantly greater myopic shift in the high myopic eyes [-1.08 ±0.87 diopters(D)] than that in the non-high myopic eyes(-0.43 ±0.63 D, P =0.004). Axial length and keratometric value in the high myopic eyes were significantly increased(P =0.043, 0.037 respectively),whereas those in the non-high myopic group were not significantly increased(P =0.135, 0.347 respectively). The change of the axial length in the myopic eye(0.46±0.28 mm)was greater than that in the non- high myopic eye(0.11 ± 0.34 mm; P 【0.001).CONCLUSION: High myopic eyes showed more myopic shift than non-high myopic eyes after phacovitrectomy.The cause of myopic shift in high myopic eyes seems tobe attributed to actual elongation of the axial length in high myopia.
文摘This paper introduces a high precision 7m laser measuring instrument developedby the anthors and its operating principle,and systematically analyses the errors havinginfluence on the performance of the measuring instrument.Error analysis and actualverification indicate that all the characteristics reached or exceeded the original designspecifications.
基金Project (No. 60172030) partially supported by the National Natural Science Foundation of China
文摘Reversible variable length codes (RVLCs) have received much attention due to their excellent error resilient capabilities. In this paper, a novel construction algorithm for symmetrical RVLC is proposed which is independent of the Huffman code. The proposed algorithm's codeword assignment is only based on symbol occurrence probability. It has many advantages over symmetrical construction algorithms available for easy realization and better code performance. In addition, the proposed algorithm simplifies the codeword selection mechanism dramatically.
文摘<strong>Background: </strong>Population ageing is a worldwide phenomenon. It is common for older adults to develop multiple age-related illnesses and the prevalence of multimorbidity increases substantially with age. Multimorbid adults are frequently treated with several concurrent medications and the regimen may be complex requiring multiple steps in the preparation of a medication prior to its administration. Polypharmacy is a concerning trend and older adults have a 100% risk of experiencing adverse drug events when taking ten or more medications concurrently. Discharge summaries communicating the number of medications, changes made to medication regimens during hospitalisations and the requirement for ongoing monitoring in the community are often incomplete. The aim of this study was to investigate contributing factors to medication-related hospitalisation, length of stay or readmission in older community-dwelling persons and examine the quality of discharge summaries. <strong>Methods: </strong>Descriptive and correlational analyses of demographic, clinical, admission, readmission, length of stay and medication variables were examined in Australia in 2016-2018. Discharge summaries were analysed for completeness, timeliness and interprofessional communication. <strong>Results: </strong>There were 295 participants, mean age 80 years, 55% were female, taking an average of 11 prescribed medications and with a mean Medication Regimen Complexity Index score of 34. Medication errors that were unrecognised at the time of hospitalisation were present in 19% of the sample. Factors associated with medication error were older age and a longer median length of stay. Fewer than 52% of these older patients had detailed discharge summaries. <strong>Conclusion: </strong>The prevalence of polypharmacy and medication regimen complexity at admission was high. A high proportion of older adults on medical units may have unrecognised medication errors impacting their admission. Medical discharge summaries are inadequately addressing this issue for patients returning to the care of their family physician.
