Objective:To develop a method for determining deoxynivalenol in four kinds of traditional Chinese herbal medicines. Methods:After being extracted by water, purified by an immunoaffinity column, deoxynivalenol was analyzed by LC-MS-MS. Results:The calibration curve was linear within the range of 2-50 ng·ml-1 for deoxynivalenol. The recovery was 68. 7%-88. 3%. Conclusion:The method is simple, sensitive and accurate in the determination of deoxynivalenol in Semen Ziziphi Spinosae, Semen Sojae Praepara-tum, Semen Coicis and Fructus Psoraleae.

Objective To investigate the clinical diagnostic value and pathogenesis of serum protein identification in Keshan disease (KD).Methods A total of 65 chronic KD patients were selected as the patient group in KD endemic areas,while 29 cases of dilated cardiomyopathy (the DCM group),62 healthy cases from KD endemic areas (control 1 group) and 28 healthy cases from non-endemic areas (control 2 group) were selected as controls.Liquid chip time of flight mass spectrometry (ClinProtTM MALDI-TOF-MS) was used to determine the expression of proteins/peptide peaks.ClinProTools 2.2 software was used to analyze the protein profiles to determine differentially expressed proteins/peptide peaks.The Genetic Algorithm (GA),QuickClassifer Algorithm (QC) and Supervised Neural Network Algorithm (SNN) methods were used to screen marker proteins.Matrix-assisted laser desorption/ionization time-of-flight Mass Spectrometry technique (MALDI-TOF/TOF) was also used as a secondary mass spectrometry to identify differentially expressed peptides.Results Between the KD and control 1 groups,34 differentially expressed proteins/peptides and 5 marker proteins were identified,while 52 differentially expressed proteins/peptides and 5 marker proteins were identified between the KD and control 2 groups,and there were 67 differentially expressed proteins/peptides and 5 marker proteins between the KD and DCM groups.During secondary mass spectrometry,two peptides for mass-to-charge ratio (m/z) 2 079 and 1 465 were obtained,peptide of matching β-globin showed low expression while peptide of matching fibrinogen showed high expression in the KD patients.Conclusions Serum marker proteins can be used as biomarkers for diagnosis and differentiation of KD.β-globin and fibrinogen play an important role in the development of KD myocardial injury.

BACKGROUND: Attachment reflects the early social experience of infant, which plays an important role in later child development. Although most of the attachment develops between infant and mother, some may occur between infant and care giver or others who have close relationship with it.OBJECTIVE: To analyze the infant-mother attachment patterns and the factors related to infant attachment.DESIGN: It was a sampling investigation.SETTING: Department of Maternal and Child Health, School of Public Health, Sun Yat-sen University.PARTICIPANTS: Totally 75 infants and their mother were selected randomly for this study in the Department of Child Health in Guangdong Maternal and Child Health Hospital from August to October 2002.METHODS: Strange situation test (SST) was performed by 6 researchers who were trained systematically. They watched the videos collectively and classified the patterns of infant attschment based on their performance. The internal consistency coefficient was 0.90. For those inconsistent assessments, the video should be reviewed and discussed to get an accordant conclusion. In addition, a self-designed maternal questionnaire was used to investigate the general condition of the infant and the familial information.MAIN OUTCOME MEASURES: ①Distribution of infant attachment patterns. ②Analysis of the risk factors related to infant attachment.RESULTS: All the 75 infants and their mother entered the statistical analysis. ①Distribution of the infant attachment patterns: In 75 infants, secure attachment was 65% and insecure attachment was 35%, among which,insecure-indifferent type was 18%, insecure-importunate type was 13%,and insecure-disorganized type was 4%. ②Analysis of the risk factors related to infant attachment Those infants with a younger age, a poor approachability (the response to strangers, new environment and objects), a closer relationship with caregiver and a more inconsistent education from the family members, are prone to develop insecure attachment.CONCLUSION: Secure attachment is dominant in infants. The security of attachment is related to the maturity and personality traits of the infants,the relationship between infant and caregiver and the educational approach for them. Key words Object attachment; Infant; Factor analysis, statistics

Objective: To explore the association between negative life events and smartphone addiction among middle school students, so as to provide theoretical support and practical guidance for prevention and intervention of smartphone addiction among middle school students. Methods: Using cluster sampling, 8 890 students were selected to survey from 27 junior high schools and 3 senior high schools in a district of Shenzhen in 2022 (baseline) and 2023 (followup). Data were collected through selfresigned questionnaires on basic information, the Smartphone Addiction Scale-Short Version, and the Adolescent Selfrating Life Events Checklist. Mixedeffects models were employed to analyze the association. Results: Compared to 2022, the punishment scores of middle school students in 2023 [1.00 (0.00, 6.00) and 1.00 (0.00, 6.00)] decreased (Z=4.27), while the scores of interpersonal stress, learning stress and adaptation [4.00(0.00, 8.00), 4.00(0.00, 8.00); 4.00(1.00, 8.00), 5.00(2.00, 9.00); 2.00 (0.00, 6.00), 3.00 (0.00, 7.00)] increased (Z=-3.04, -8.36, -6.80) (P<0.01). Mixedeffects models revealed a positive doseresponse relationship between negative life events and smartphone addiction (OR=1.08-1.17, P<0.01). Stepwise regression showed independent positive effects of interpersonal stress (OR=1.05), academic stress (OR=1.03), and adaptation stress (OR=1.11) on smartphone addiction (P<0.01). Subgroup analysis of nonaddicted students in 2022 confirmed persistent associations for academic stress (OR=1.03) and adaptation (OR=1.07) (P<0.01). Conclusion Negative life events exhibit a positive doseresponse relationship with smartphone addiction, particularly interpersonal stress, academic stress, and adaptationrelated events.

Objective: To explore the longitudinal association between only-child status and smartphone addiction among middle school students, so as to provide a basis for establishing family intervention measures for smartphone addiction in middle school students. Methods: In October 2022 and October 2023, a preliminary survey and follow-up were conducted among 8 759 middle and high school students from 30 schools in a district of Shenzhen. A self-designed questionnaire was used to determine whether the students were the only-child, and the Chinese Version of the Smartphone Addiction Scale-Short Version (C-SAS-SV) was utilized to assess the students smartphone addiction status. A multilevel mixed-effects model and subgroup analysis were applied to examine the association between only-child status and smartphone addiction among middle school students. Results: During 2022 to 2023, the prevalence of smartphone addiction in the cohort of middle school students increased from 24.1% to 25.2%. Compared with only-child, non-only child were more likely to be addicted to smartphones (adjusted model: OR =1.2, 95% CI =1.1-1.4) and also scored higher on smartphone addiction (adjusted model: β =0.9, 95% CI =0.2-1.5)( P <0.05). Subgroup analysis further revealed that compared to baseline, non-only child demonstrated an increased prevalence of smartphone addiction (adjusted model: OR = 1.2 , 95% CI =1.0-1.5) and higher addiction scores (adjusted model: β =0.8, 95% CI =0.2-1.5) after one year( P <0.05). Conclusions Non-only child face higher risk of smartphone addiction. Under the current population policy, it is crucial to address smartphone addiction among middle school students who is not only child.

Objective: To explore the potential causal association between adolescent compulsive behaviour and smartphone addiction based on longitudinal data, so as to provide reference for the establishment of adolescent smartphone addiction interventions. Methods: A preliminary survey and follow-up were conducted on 8 907 middle and high school students in a district of Shenzhen in 2022 and 2023, respectively. Compulsive behaviours were measured by using the Mental Health Inventory for Middle School Students-60 Items (MMHI-60), smartphone addiction was assessed by using the Smartphone Addiction Scale-Short Version ( SAS- SV), and the associations between compulsive behaviours and smartphone addiction were analysed by using multilevel mixed-effects models and subgroup analyses. Results: Smartphone addiction detection rates among middle school students were significantly associated with genders, father s education level, mother s education level, study load subgroups, and whether or not they were single-parent families, and there were statistical differences ( χ 2=17.21-175.34, P <0.05). Students with compulsive behaviours were 2.98 times more likely to develop smartphone addiction than those without compulsive behaviours ( OR=2.98, 95%CI=2.77-3.22, P <0.05). Subgroup analysis of middle school students without smartphone addiction in the first year found that compulsive behaviours significantly predicted smartphone addiction ( OR= 1.76 , 95%CI=1.54-2.01, P <0.05). Conclusion There is a potential causal association between obsessive-compulsive behaviours and smartphone addiction in middle school students, and obsessive-compulsive behaviours in middle school students could significantly predicted the occurrence of smartphone addiction.

OBJECTIVE： To establish a method for rapid determination of total phenylethanoid glycosides and total iridoid glycosides in the root of Rehmannia glutinosa. METHODS： The contents of total phenylethanoid glycosides and total iridoid glycosides in medicinal material samples were determined by UV spectrophotometry. Quantitative model of total phenylethanoid glycosides and total iridoid glycosides in medicinal samples was established by NIRS-PLS method. The optimal pretreatment spectra were multivariate scattering correction combined with first derivative method， standard normalization combined with first derivative method. The optimum spectral ranged from 6 703.35-11 065.54 cm－1 and 3 999.63-9 102.36 cm－1. The optimum principal factor number were 10 and 7. RESULTS： The content determination of total phenylethanoid glycosides and total iridoid glycosides in medicinal material samples was proved to meet the requirements by methodological experience. The internal cross validation determination coefficients of total phenylethanoid glycosides and total iridoid glycosides were 0.998 2 and 0.980 9. The correction of root mean square error was 0.032 7 and 0.186 0. The root mean square error of prediction were 0.035 5 and 0.035 1. The root mean square error of cross validation were 0.256 9 and 0.574 3. The predicted values of total phenylethanol glycosides and total iridoid glycosides were 0.268％-1.636％ and 3.424％-6.978％， respectively； the determination value of them were 0.299％-1.629％ and 3.431％-6.952％， respectively； the absolute deviations were －0.042％-0.067％ and －0.111％-0.088％， respectively；the relative deviations were －0.819％-0.076％、－2.257％-1.672％， respectively；There was no statistical significance between predicted values and measured values （P＞0.05）. CONCLUSIONS： The method is accurate and simple. The method can be used for the rapid determination of total phenylethanoid glycosides and total iridoid glycosides in different germplasms of R. glutinosa.