Objective:To examine the roles played by peer attachment and cognitive fusion in the association between negative life events and depression,as well as the differences in these relationships of variables among pri-mary and secondary school students.Methods:A total of 2 767 students(1 950 elementary school students and 817 middle school students)were selected.The Adolescent Life Events Scale,the Experiences in Close Relationships-Relationship Structures Questionnaire,the Cognitive Fusion Questionnaire,and the Patient Health Questionnaire were used to measure negative life events,peer attachment,cognitive fusion,and depression,respectively.Results:Negative life events,peer attachment,cognitive fusion and depression were positively correlated with each other(r=0.36-0.75,Ps＜0.001);the mediation effects of peer attachment and cognitive fusion and their chain mediation effects were 0.04,0.30,and 0.04,respectively,accounting for 6.7％,50％,and 6.7％of the total effect.There were significant differences in the chain mediation model between primary and secondary school students(△x2=47.12,△df=6,P＜0.001),and significant gender differences in the chain mediation effect among primary school students(△x2=43.72,△df=6,P＜0.001).Conclusion:Negative life events influence depression in primary and secondary school students both directly and indirectly through peer attachment and cognitive fusion.Negative life e-vents have greater impact on primary school students'(particularly girls)peer attachment.Peer attachment has grea-ter impact on secondary school students' cognitive fusion.Cognitive fusion has greater impact on primary school students' depression.Peer attachment has greater impact on primary school boys' depression.

Objective:To examine the roles played by peer attachment and cognitive fusion in the association between negative life events and depression,as well as the differences in these relationships of variables among pri-mary and secondary school students.Methods:A total of 2 767 students(1 950 elementary school students and 817 middle school students)were selected.The Adolescent Life Events Scale,the Experiences in Close Relationships-Relationship Structures Questionnaire,the Cognitive Fusion Questionnaire,and the Patient Health Questionnaire were used to measure negative life events,peer attachment,cognitive fusion,and depression,respectively.Results:Negative life events,peer attachment,cognitive fusion and depression were positively correlated with each other(r=0.36-0.75,Ps＜0.001);the mediation effects of peer attachment and cognitive fusion and their chain mediation effects were 0.04,0.30,and 0.04,respectively,accounting for 6.7％,50％,and 6.7％of the total effect.There were significant differences in the chain mediation model between primary and secondary school students(△x2=47.12,△df=6,P＜0.001),and significant gender differences in the chain mediation effect among primary school students(△x2=43.72,△df=6,P＜0.001).Conclusion:Negative life events influence depression in primary and secondary school students both directly and indirectly through peer attachment and cognitive fusion.Negative life e-vents have greater impact on primary school students'(particularly girls)peer attachment.Peer attachment has grea-ter impact on secondary school students' cognitive fusion.Cognitive fusion has greater impact on primary school students' depression.Peer attachment has greater impact on primary school boys' depression.

Objective: To examine the influence of school adaptation on depression among high school students, as well as the mediating effects of social avoidance and distress and learning burnout on the relationship between school adaptation and depression among high school students, so as to provide a basis for the mental health promotion among high school students. Methods: A convenience sampling method was used to select 1 207 first year high school students from two high schools as the research subjects in Guiyang City. The School Adaptation Scale(SAS), Social Avoidance and Distress Scale(SAD), Learning Burnout Questionnaire(LBQ), Patient Health Questionnaire-9(PHQ-9) were used to conduct surveys at three time points: October 2021 (T1), May 2022 (T2), and March 2023 (T3). Common method biase was tested using the Harman s single factor method,and bias correction was conducted via the Bootstrap method, utilizing 5 000 resamples to analyze the 95% confidence intervals(95% CI ) of parameter estimates. Results: School adaptation at T1 was negatively associated with depression of high school students at T3 ( β =-0.13, P <0.01). The mediation analysis showed that the mediating effect of social avoidance and distress at T2 between school adaptation at time point T1 and depression among high school students at time point T3 was-0.100 (95% CI =-0.134--0.071, P <0.05). The mediating effect of learning burnout at T2 between school adaptation at time point T1 and depression among high school students at time point T3 was-0.157 (95% CI =-0.211--0.106, P <0.05). The chain mediation effect of social avoidance and distress and learning burnout at T2 between school adaptation at time point T1 and depression among high school students at time point T3 was -0.022 (95% CI =-0.037--0.012, P <0.05). Conclusions Good school adaptation can directly alleviate depressive mood, and can indirectly reduce depression through social avoidance and distress and learning burnout among high school students. Families and schools should pay attention to the school adaptation of high school students and provide timely interventions and assistance to students with poor adaptation.

Objective:To observe and summarise the clinical effect of free groin flap in repairing of soft tissue defects in extremities, and to explore the selection of main vessel in a flap.Methods:From January 2018 to January 2021, 146 patients with soft tissue defects in extremities were treated with free groin flaps in the Department of Hand and Microsurgery, Guangxi Guilin Xing'an Jieshou Orthopaedic Hospital. There were 126 patients with traumatic wound and 20 with chronic ulcer. In addition, 86 of the patients with bone fracture and exposure of internal fixator, 18 with tendon, nerve or artery injuries or defects. There were 6 patients with severe infection and other 3 with deep dead space. The sizes of wound ranged from 2.0 cm×3.0 cm to 25.0 cm×6.0 cm. The flap was the same size as the wound and not enlarged. Firstly, the superficial branch of superficial iliac circumflex artery was explored as the axial artery for all the flaps, then the blood supply vessels of the flap were selected according to the availability of the axial artery. The size, course, adjacent and possible length to be freed of the axial artery and the accompanying veins of a flap were recorded. The donor sites were directly sutured and closed. All patients were included in the postoperative follow-up at outpatient clinic.Results:Free groin flap were used to repair the wounds in all patients. However, the main blood supply vessel of the flap was not constant, and it was often required to adjust the way of flap harvesting. Superficial circumflex iliac artery was taken as the axial vessels in 141 patients (96.6%), among them, 133 cases(94.3%) had the superficial branch as the axis and 5 cases (3.6%) had deep branch as the axis. Three patients (2.1%) had the bone and soft tissue defects reconstructed with vascularised iliac mosaic osteocutaneous flap with superficial circumflex iliac artery as axial vessel and 5 cases(3.4%) had the superficial epigastric artery as axial vessel. The axial arteries were measured as follow: the superficial branch of the superficial circumflex iliac artery was 0.5-0.9 mm in diameter and 7.0-9.0 cm in length, the outer diameter of the deep branch was 1.2-1.4 mm and 9.0-11.0 cm in length, and the outer diameter of superficial epigastric artery was 1.0-1.6 mm and 8.0-11.3 cm in length. All the flaps survived smoothly after surgery and the follow-up period ranged 6-40 (mean 26) months. The texture of the flaps was soft with good function.Conclusion:Free groin flap can be used to repair soft tissue defects in extremities. The main axial vessel is the superficial branch of the superficial circumflex iliac artery, followed by the deep branch or the trunk. The superficial abdominal artery can also be used as an axial vessel. Under the circumstances, the flap design needs to be adjusted without changing the supply area