1.Measurement Uncertainty Evaluation of Automatic Verification Device for Laser Protective Spectacles
Zhenkun LUO ; Rong SUN ; Qiuhua WANG ; Haifeng LIU
Chinese Medical Equipment Journal 2003;0(12):-
Objective To test and evaluate measurement uncertainty and relational performance parameters of the verification device for laser protective spectacles.Methods By using realtime beam-splitting surveillance,several performance parameters,including the measurement repeatability of the verification device,optical density of laser protective spectacles in different laser exposure conditions and its damage threshold,were tested.The measurement modules of the main performance parameters were built up as the experiment & technology platform for performance evaluation of laser protective spectacles and for measurement uncertainty appraisal of verification device.Results Laser wavelengths of the verification device were 1064nm and 532nm,response range of wavelength was from 0.4?m to 1.1?m,measuring range of laser energy was from 10-8 J to 0.3J,measuring range of optical density for laser protective spectacles was from 0.1 to 8.0,measuring repeatability was 0.37%,and measuring uncertainty was 5% (k =2).Conclusion The automatic verification device is steady and reliable.The achieved performance indexes accord with the designed requirement for laser protection.
2.Research of the Automatic Verification Device and Testing Technology for Laser Protective Spectacles
Zhenkun LUO ; Haifeng LIU ; Rong SUN ; Chong MA ; Baoliang ZHU ; Li LIU ; Guanghuang GAO ; Shilin SU
Chinese Medical Equipment Journal 2009;30(7):17-20
Objective Based on the principles of laser radiation protection, medical metroiogy and photoelectron technology, an automatic verification device and testing technology to provide verification and performance evaluation for laser protective spectacles and equipments which have the various functions in laser protection have been developed and established. Methods The current system comprises laser source, laser measuring instruments, software of computer detection and control and modules of optics and mechanics used in auxiliary equipment. By use of the verification device and the special test-recording method to be designed and studied by us, the measured data can be automatically acquired, processed, recorded, saved and printed and, furthermore, many parameters on protective performance of the measured laser protective spectacles can be tested and given. Results Laser wavelength of the verification apparatus are 1 064 nm and 532 nm, response range of wavelength is from 0.4 m to 1.1 μm, measuring range of laser energy is from 10-8 J to 0.3 J, measuring range of optical density for laser protective spectacles is from 0.1 to 8.0, stability is 0.21%, measuring uncertainty is 5%(k=2). Conclusion The automatic verification device is steady and reliable. The achieved performance indexes accord with the requirement of national standard on laser protection.
3.Establishment and validation of depressive symptom predictive model in middle school students
TAN Zhenkun, ZHANG Zhuo, ZHANG Ying, PING Junjiao, LUO Jiali, ZHANG Jie, LIU Xinxia
Chinese Journal of School Health 2024;45(7):998-1002
Objective:
To investigate the influencing factors of depressive symptoms and to construct and verify the prediction model of depressive symptoms in middle school students, so as to provide risk assessment tools for effectively screening depressive symptom.
Methods:
Physical examination and questionnaire survey were conducted among middle school students in one city in Guangdong Province from September to October in 2021 ( n =2 376) and from September to October in 2022 ( n =4 344) by a multistage cluster sampling method, and a nomographic prediction model of depressive symptoms in middle school student was constructed. The questionnaire survey was conducted using the student health status and influencing factors questionnaire (secondary school version) and the Center for Epidemiological Studies Depression Scale (CES-D) to measure the lifestyle and depressive symptom of middle school students.
Results:
The detection rate of depressive symptoms in 2021 was 23.3%. Multivariate Logistic regression analysis showed that irregular breakfast ( OR =2.64), school bullying ( OR =4.28), being beaten by parents ( OR =2.86), using mobile devices for a long time ( OR =1.08) and sitting for a long time ( OR =1.05) were positively related to depressive symptoms in middle school students ( P <0.05). Long sleep duration ( OR =0.78) and outdoor activity durations of 1-<2, 2-<3 and ≥3 h/d (compared with <1 h/d, OR =0.63, 0.61, 0.49) were negatively related to depressive symptoms in middle school students ( P < 0.05 ). Multivariate Logistic regression analysis showed that 7 statistically signifucant predictive factors constructed a nomogram, and the AUC of the nomogram was 0.77, which had been verified internally and externally with good differentiation and reliability.
Conclusions
The nomogram prediction model of depressive symptoms provides a convenient and effective risk assessment tool for depressive symptoms among middle school students. The life behavior, diet behavior and injury behavior of middle school students play an important role in the formation of depressive symptoms. It should pay attention to the impact of the behavioral factors on the mental health of middle school students.
4.Application of micro-lectures combined with high simulation human in clinical skills teaching for nursing students
Yangping LI ; Liang LUO ; Fengjuan JIN ; Yanan ZHANG ; Yuan GAO ; Zhenkun HAN ; Hong CHEN
Chinese Journal of Practical Nursing 2018;34(24):1898-1902
Objective To explore the effect of micro-lectures withadvanced simulation man in improving the practical skills teaching of nursing students, so as to promote the students' post competency. Methods Totally the 186 nursing internswere divided into control group and observation group by random number method with 93 people in each group. The control group used the traditional teaching modein the teaching of practical skills.The observation group used the micro-lectures with high simulation teaching.Comparing the two groups of nursing students comprehensive assessment test simulation results in the theory, skills, scenarios, and nursing students the evaluation of the curriculum. Results The scores of the two groups were all above the qualification line, but the scores of the observation group were significantly higher than those of the control group (P<0.05). The theoretical examinations and the situation simulation comprehensive testswas(77.89 ± 7.79), (75.60 ± 7.92)points in control group, and (93.87 ± 3.90),(92.87 ± 4.08)points in observation group, there was significant difference between two groups (t=17.67, 18.70,all P=0.000). The curriculum evaluation results of improving learning initiative, active curriculum atmosphere, clear operation demonstration, exercise clinical thinking, improve the clinical interest were 81.72%(76/93), 72.04%(67/93), 93.55%(87/93), 60.22%(56/93), 67.74%(63/93)in control group, and 96.77%(90/93), 95.70%(89/93), 100.00%(93/93), 92.47%(86/93), 98.92%(92/93)in observation group, there was significant difference between two groups(χ2=20.39, P=0.016).Conclusions The effect is significant of micro-lectures combined with high simulation of human using in clinical skills teaching. Thismold can conducive to the cultivation of clinical thinking of nursing students, and improve clinical comprehensive ability, and promote the promotion of nursing students post competency.
5.Causal relationship between gout and Alzheimer's disease: a two-sample Mendelian randomization analysis
Chuijia KONG ; Ying ZHANG ; Zhenkun TAN ; Junjiao PING ; Haibo ZHANG ; Jie ZHANG ; Jiali LUO ; Xinxia LIU
Sichuan Mental Health 2025;38(2):115-122
BackgroundDementia seriously affects the quality of life and lifespan of elderly people, with Alzheimer's disease (AD) being the most common type of dementia. Previous studies have suggested that gout may reduce the risk of developing AD, but the causal relationship between the two still requires further research. ObjectiveTo investigate the potential causal relationship between gout and AD through a two-sample Mendelian randomization (MR) analysis, so as to provide references for the prevention and treatment of AD. MethodsData from Genome-Wide Association Studies (GWAS) extracted in 2024 were analyzed, using pooled data on gout (6 810 cases in the case group and 477 788 cases in the control group) published by UK Biobank in 2021 as the exposure variable, and data on AD (3 899 cases in the case group and 214 893 cases in the control group) published by FinnGen in the same year as the outcome variable. The inverse-variance weighted, MR-Egger regression, weighted median estimation, simple model and weighted model were used to analyze the potential causal relationship between gout and AD. Pleiotropic effects were assessed using MR-Egger regression. Heterogeneity assessment was conducted using Cochran's Q test. The leave-one-out analysis was carried out for sensitivity analysis. And a funnel plot was drawn to detect potential publication bias. ResultsThe inverse-variance weighted analysis demonstrated a negative causal relationship between gout and AD (OR=0.004, 95% CI: 0~0.700, P<0.05). The plot resembled a symmetrical inversed funnel, indicating the absence of publication bias. No heterogeneity was detected by Cochran's Q test. The MR-Egger regression indicated no significant horizontal pleiotropy. Concerning the reverse directions, no significant associations between AD and gout were noted. ConclusionThere is a negative causal relationship between gout and AD, with gout potentially reducing the risk of developing AD. [Funded by The Third Batch of Social Welfare and Basic Research Projects (Medical and Health) of Zhongshan City in 2022 (number, 2022B3017)]
6.Association between urinary metal mixtures and mild cognitive impairment among elderly residents in Guangdong compounds
Chuijia KONG ; Ying ZHANG ; Zhenkun TAN ; Junjiao PING ; Haibo ZHANG ; Jiali LUO ; Xinxia LIU
Journal of Environmental and Occupational Medicine 2025;42(8):893-899
Background Environmental metal exposure is closely associated with the onset and progression of mild cognitive impairment (MCI) in the elderly. Effectively identifying hazardous metal exposure and assessing their interaction effects have significant public health implications. Objective To explore the relationship between urinary single metal and metal mixture exposure and MCI in elderly compound residents. Methods This study included 391 elderly individuals aged 60 and above from residential compounds in Zhongshan City, Guangdong Province. Concentrations of iron (Fe), copper (Cu), selenium (Se), arsenic (As), cadmium (Cd), manganese (Mn), chromium (Cr), nickel (Ni), vanadium (V), cobalt (Co), antimony (Sb), thallium (Tl), zinc (Zn), calcium (Ca), and magnesium (Mg) in urine were measured using inductively coupled plasma mass spectrometry. Cognitive function in the elderly was assessed using the Chinese version of the Mini-Mental State Examination (MMSE). Logistic regression was used to explore the relationship between single metal exposure level and MCI. LASSO regression and multi-metal logistic regression models were used to identify key metal ions associated with MCI. Bayesian kernel machine regression (BKMR) was employed to analyze the relationship between key metal ion mixtures and MCI, as well as the interactions between metals. Age, gender, education level, occupation, and body mass index were adjusted as covariates. Results A total of 78 among the 391 elderly individuals surveyed (19.94%) were diagnosed with MCI (MCI group), and the other 313 individuals were controls. The levels of Se, Cd, Mn, and As in the urine of the MCI group were significantly higher than those in the control group (P < 0.05). In the single-metal model, after adjusting for covariates and using the first quartile (Q1) of each metal concentration as the reference, the OR for MCI in the elderly in the Q4 group of Se was 2.190 (95%CI: 1.017, 4.716); for Cd, the OR was 2.345 (95%CI: 1.041, 5.283) in the Q3 group and 2.371 (95%CI: 1.043, 5.393) in the Q4 group; for Mn, the OR was 2.355 (95%CI: 1.038, 5.344) in the Q2 group; for As, the OR was 3.377 (95%CI: 1.442, 7.908) in the Q3 group and 2.886 (95%CI: 1.227, 6.788) in the Q4 group; for Sb, the OR was 2.779 (95%CI: 1.234, 6.257) in the Q2 group. When urinary metal concentrations were ln-transformed and included as continuous variables in the single-metal model, Cd concentration was positively correlated with MCI (OR=1.377; 95%CI: 1.008, 1.882; P=0.044). Cd, Se, Mg, Ca, Mn, As, Cr, Co, Tl, and Sb were selected by the LASSO regression model and included in the multi-metal model. In the multi-metal model, compared with Q1, the OR for MCI in the elderly was 0.395 (95%CI: 0.164, 0.953) in the Q2 group of Co and 0.390(95%CI: 0.167,0.911) in the Q3 group of Co; for Mn, the OR in the Q2 group was 2.636 (95%CI: 1.053, 6.596); for Sb, the OR in the Q2 group was 2.640 (95%CI: 1.047, 6.658). As continuous variables, Mg (OR=0.472; 95%CI: 0.248, 0.899; P=0.022) and Co (OR=0.857; 95%CI: 0.737, 0.996; P=0.044) concentrations were negatively correlated with MCI. The BKMR mixture analysis suggested that Mg and Co exhibited a synergistic negative correlation with MCI, while Mn and Sb exhibited a synergistic positive correlation with MCI. Mg and Co attenuated the positive correlation of Mn and Sb with MCI, whereas Mn weakened the protective effects of Mg and Co. Conclusion Elevated levels of Se, Cd, As, Mn, and Sb in urine may increase the risk of MCI in the elderly, while Mg and Co have protective effects. Potential synergistic or antagonistic interactions may be found among Mn, Sb, Mg, and Co, which should not be overlooked in terms of their impact on the cognitive function of the elderly.