Coping as a Mechanism Linking Stressful Life Events and Mental Health Problems in Adolescents

Objective Although stressful life events represent an etiologic factor of mental health problems in adolescents, few studies have been conducted to address mechanisms linking the stress-psychopathology relation. The present study was designed to examine coping as a mediate factor on the relationship between stressful life events and symptoms of anxiety and depression. Methods The participants were 13 512 students from eight cities of China, who participated in a school-based survey. Data were collected by a questionnaire comprising coping, stressful life events, anxiety, and depressive symptoms. As a model, a series of regression equations were used to examine whether coping mediated the association between stressful life events and symptoms of anxiety and depression. Results Each dimension of stressful life events showed significant correlation with anxiety, depression and coping （all P〈0.001）. In the model to analyze mediate effects, all standardized coefficients （β） were significant （all P〈0.01）, indicating marked mediator effects. Furthermore, negative coping might account for more mediate effects than positive coping on this relationship. Conclusion Coping partially mediated the relationship between stressful life events and mental health during adolescence. This study highlighted an important public health priority for preventive interventions targeting stress-related psychopathology, and for further promoting adolescents＇ mental health.

Psychological impact of chronic hepatitis C:Comparison with other stressful life events and chronic diseases

AIM： To examine the psychological impact of chronic hepatitis C （CHC） diagnosis in a large cohort of CHC patients as compared with other stressful life events and chronic diseases carrying a risk of life-threatening complications. METHODS： One hundred and eighty-five outpatients with compensated CHC were asked to self-grade, using a 100-mm visual analogue scale （VAS）, the degree of stress caused by the learning of CHC diagnosis and the perceived severity of their disease. Diagnosis-related stress was compared to four other stressful life events and perceived CHC severity was compared to four other common chronic diseases. RESULTS： Learning of CHC diagnosis was considered a major stressful event （mean ± SD scores： 72±25）, significantly less than death of a loved-one （89±13, P〈0.0001） and divorce （78 ± 23, P〈0.007）, but more than job dismissal （68 ± 30, P〈 0.04） and home removal （26±24, P〈 0.0001）. CHC was considered a severe disease （74± 19）, after AIDS （94±08, P〈 0.001） and cancer （91± 11, P〈 0.001）, but before diabetes （66±23, P〈0.001） and hypertension （62±20, P〈0.001）. Perceived CHC severity was not related to the actual severity of liver disease, assessed according to Metavir fibrosis score. In multivariate analysis, diagnosisrelated stress was related to perceived disease severity （P〈0.001）, trait anxiety （P〈 0.001） and infection through blood transfusion （P〈 0.001）. CONCLUSION： Our results show the considerable psychological and emotional burden that a diagnosis of CHC represents, even in the absence of significant liver disease. They should be taken into account when announcing a diagnosis of CHC in order to reduce its negative effects.

Childhood stressful events, HPA axis and anxiety disorders

Anxiety disorders are among the most common of all mental disorders and their pathogenesis is a major topic in psychiatry, both for prevention and treatment. Early stressful life events and alterations of hypothalamic pituitary adrenal(HPA) axis function seem to have a significant role in the onset of anxiety. Existing data appear to support the mediating effect of the HPA axis between childhood traumata and posttraumatic stress disorder. Findings on the HPA axis activity at baseline and after stimuli in panic disordered patients are inconclusive, even if stressful life events may have a triggering function in the development of this disorder. Data on the relationship between stress, HPA axis functioning and obsessive-compulsive disorder(OCD) are scarce and discordant, but an increased activity of the HPA axis is reported in OCD patients. Moreover, normal basal cortisol levels and hyperresponsiveness of the adrenal cortex during a psychosocial stressor are observed in social phobics. Finally,abnormal HPA axis activity has also been observed in generalized anxiety disordered patients. While several hypothesis have attempted to explain these findings over time, currently the most widely accepted theory is that early stressful life events may provoke alterations of the stress response and thus of the HPA axis, that can endure during adulthood, predisposing individuals to develop psychopathology. All theories are reviewed and the authors conclude that childhood life events and HPA abnormalities may be specifically and transnosographically related to all anxiety disorders, as well as, more broadly, to all psychiatric disorders.

Volumetric changes in the focal areas of seismic events corresponding to destress blasting

The typical development of total volumetric change in the focal areas of seismic events,corresponding to destress blasting,is characterized as an explosive phase followed by an implosive phase and with alternating additional phases following on from that.In a few cases,a non-typical development of volumetric change was identified,where the first phase was implosive and the second phase,explosive.This development is mainly typical for induced seismic events recorded during mining,not for destress blasting.Seismic events were recorded during longwall mining in the Czech part of the Upper Silesian Coal Basin,where the destress blasting technique is used as a rockburst prevention active measure.Kinematic source processes in the focal areas of selected seismic events were analyzed by the seismic moment tensor inversion method,as well as by studying geomechanical rock mass conditions at the localities of the seismic events.The main goal of the analysis was to attempt to identify the reasons for non-typical development of volumetric changes in these cases.Volumetric changes were analyzed for seismic events with energy greater than 104 J,recorded in the period of time from 1993 to 2009(1109 events).80%(891)of the recorded seismic events were induced seismic events that were registered during longwall mining and 20%(218)corresponded to destress blasting events.Research shows that the main reason for the non-typical development of volumetric changes in the focal areas of seismic events is an association with destress blasting in the rock mass,which is very close to rock mass overstressing.The detonation of explosives in boreholes,which would dominate the first phase of volumetric changes,probably obscured stress release in the rock mass,as manifested in the first implosion phase of the volumetric changes in this case.

Recurrent Takotsubo cardiomyopathy triggered by emotionally stressful events: A case report

BACKGROUND Takotsubo cardiomyopathy(TCM)is characterized by reversible left ventricular dysfunction triggered by emotional or physical stress.Only 1%-2%of patients with acute coronary syndrome are diagnosed with TCM.Although obstructive coronary artery disease is frequently considered to be the cause of chest pain,TCM should be considered in some clinical settings.In this case,clinicians did not make a timely and accurate diagnosis for TCM due to a lack of knowledge until the third hospitalization with a left ventriculogram.CASE SUMMARY A 55-year-old postmenopausal woman had intermittent chest pain following emotionally stressful events three times in the past 3 years.Cardiac troponin levels increased after each instance of symptom onset.A transthoracic echocardiogram showed reversible left ventricular dysfunction.The patient underwent three coronary angiograms without evidence of coronary artery disease.A left ventriculogram was first performed at the third hospitalization and revealed apical akinesia with ballooning of the apical region and consistent hypercontractile basal segments.The diagnosis of TCM was confirmed.The patient was treated with an angiotensin-converting-enzyme inhibitor(perindopril)and aβ-blocker(metoprolol).No complications occurred during the patient’s hospitalization.The patient was told to avoid stressful events.During the 9-mo follow-up visit,the patient was asymptomatic with an ejection fraction of 55%.CONCLUSION Clinicians should be conscious of the possibility of TCM,especially in postmenopausal women presenting with clinical manifestations similar to acute coronary syndrome without coronary occlusion.

Stressful life events and psychosocial correlates of pediatric inflammatory bowel disease activity

AIM To investigate the association of psychiatric and psychosocial correlates with inflammatory bowel disease(IBD) activity in children and adolescents.METHODS A total of 85 pediatric IBD patients(in remission or active state of the disease) and their parents completed a series of questionnaires and semi-structured interviews measuring life events,depression,anxiety,family dysfunction,and parent mental health.Differences between the remission and the IBD active group and the association of any significant variable with the disease activity state were examined.RESULTS Parents of children being in active state of the disease reported more life events(P = 0.005) and stressful life events(P = 0.048) during the past year and more mental health symptoms(P < 0.001),while the childrenthemselves reported higher levels of anxiety symptoms(P = 0.017) compared to the remission group.In the logistic regression multivariate analysis,the only predictor which had a significant positive effect on the probability of the patients being in active state was parent mental health symptoms(OR = 4.8;95%CI:1.2-25.8).CONCLUSION Life events,child anxiety and parent mental health symptoms may be important correlates of pediatric IBD activity and targets of thorough assessment and treatment.

Identification methods for anomalous stress region in coal roadways based on microseismic information and numerical simulation

It is believed that the microseismicity induced by mining effect and gas gradient disturbance stress is a precursor to the essential characteristics of roadway unstability. In order to effectively identify and evaluate the stability of coal roadways in the process of mine development and extraction, a microseismic monitoring system was deployed for the study of the stress evolution process, damage degree and distribution characteristics in the tailgate and headgate. The mine under study is the 62113 outburst working face of Xin Zhuangzi coalmine in Huainan mining area. The whole process of microfractures initiation,extension, interaction and coalescence mechanisms during the progressive failure processes of the coal rock within the delineated and typical event clusters were investigated by means of a two dimensional realistic failure process analysis code(RFPA2D-Flow). The results show that the microseismic events gradually create different-sized event clusters. The microseismicity of the tailgate is significantly higher than that of the headgate. The study indicates that the greater anomalous stress region matches the area where microfractures continuously develop and finally connect to each other and form a fissure zone.Due to the mine layout and stress concentration, the ruptured area is mainly located on the left shoulder of the tailgate roof. The potential anomalous stress region of the coal roadway obtained by numerical simulation is relatively in good agreement with the trend of spatial macro evolution of coal rock microfractures captured by the microseismic monitoring system. The research results can provide important basis for understanding instability failure mechanism of deep roadway and microseismic activity law in complex geologic conditions, and it ultimately can be used to guide the selection and optimization of reinforcement and protection scheme.

Path analysis of relationship among personality, perceived stress, coping, social support, and psychological outcomes

AIM: To provide a structural model of the relationship between personality traits, perceived stress, coping strategies, social support, and psychological outcomes in the general population.METHODS: This is a cross sectional study in which the study group was selected using multistage cluster and convenience sampling among a population of 4 million. For data collection, a total of 4763 individuals were asked to complete a questionnaire on demographics, personality traits, life events, coping with stress, social support, and psychological outcomes such as anxiety and depression. To evaluate the comprehensive relation-ship between the variables, a path model was fitted.RESULTS: The standard electronic modules showed that personality traits and perceived stress are important determinants of psychological outcomes. Social support and coping strategies were demonstrated to reduce the increasing cumulative positive effects of neuroticism and perceived stress on the psychological outcomes and enhance the protective effect of extraversion through decreasing the positive effect of perceived stress on the psychological outcomes. CONCLUSION: Personal resources play an important role in reduction and prevention of anxiety and depression. In order to improve the psychological health, it is necessary to train and reinforce the adaptive coping strategies and social support, and thus, to moderate negative personality traits.

Deformation correlations,stress field switches and evolution of an orogenic intersection:The Pan-African Kaoko-Damara orogenic junction,Namibia

Age calibrated deformation histories established by detailed mapping and dating of key magmatic time markers are correlated across all tectono-metamorphic provinces in the Damara Orogenic System.Correlations across structural belts result in an internally consistent deformation framework with evidence of stress field rotations with similar timing,and switches between different deformation events.Horizontal principle compressive stress rotated clockwise ~180°in total during Kaoko Belt evolution,and^135° during Damara Belt evolution.At most stages,stress field variation is progressive and can be attributed to events within the Damara Orogenic System,caused by changes in relative trajectories of the interacting Rio De La Plata,Congo,and Kalahari Cratons.Kaokoan orogenesis occurred earliest and evolved from collision and obduction at ~590 Ma,involving E-W directed shortening,progressing through different transpressional states with ~45° rotation of the stress field to strike-slip shear under NW-SE shortening at ~550-530 Ma.Damaran orogenesis evolved from collision at ~555-550 Ma with NW-SE directed shortening in common with the Kaoko Belt,and subsequently evolved through ~90°rotation of the stress field to NE-SW shortening at ~512-508 Ma.Both Kaoko and Damara orogenic fronts were operating at the same time,with all three cratons being coaxially convergent during the 550-530 Ma period;Rio De La Plata directed SE against the Congo Craton margin,and both together over-riding the Kalahari Craton margin also towards the SE.Progressive stress field rotation was punctuated by rapid and significant switches at ~530-525 Ma,~508 Ma and ~505 Ma.These three events included:(1)Culmination of main phase orogenesis in the Damara Belt,coinciding with maximum burial and peak metamorphism at 530-525 Ma.This occurred at the same time as termination of transpression and initiation of transtensional reactivation of shear zones in the Kaoko Belt.Principle compressive stress switched from NW-SE to NNW-SSE shortening in both Kaoko and Damara Belts at this time.This marks the start of Congo-Kalahari stress field overwhelming the waning Rio De La Plata-Congo stress field,and from this time forward contraction across the Damara Belt generated the stress field governing subsequent low-strain events in the Kaoko Belt.(2)A sudden switch to E-W directed shortening at ~508 Ma is interpreted as a far-field effect imposed on the Damara Orogenic System,most plausibly from arc obduction along the orogenic margin of Gondwana(Ross-Delamerian Orogen).(3)This imposed stress field established a N-S extension direction exploited by decompression melts,switch to vertical shortening,and triggered gravitational collapse and extension of the thermally weakened hot orogen core at ~505 Ma,producing an extensional metamorphic core complex across the Central Zone.

动载扰动诱发巷道冲击的风险性分析

巷道冲击地压发生机理与风险性评估问题,对不同区域应力场中的巷道围岩分区能量释放规律进行分析,考虑动载事件扰动,建立了始态应力场、动载事件产生的瞬态应力场与巷道围岩破坏之间的力学联系,提出了动载事件扰动下的终态巷道围岩塑性区边界计算方程,阐述了动载事件与始态应力场共同作用诱发冲击地压的机理,并对不同因素变化下的巷道冲击风险性进行了分析,以震动事件发生角为指标对动载事件发生的不同区域进行了风险强度的划分。研究结果表明:区域应力场不均匀程度的增大使得巷道围岩系统在扰动平衡后的能量释放量增大,且能量释放的主要区域为区域应力场的最大围压方向;巷道冲击地压是巷道围岩受始态应力场与动载事件的瞬态应力场2者共同作用的结果,动载事件的影响会使得巷道围岩系统的终态应力场产生偏转,而围岩协调所释放的能量是冲击产生的主要原因;当始态应力场处于蝶形风险区时,受动载事件影响后的巷道冲击风险性更大,且动载事件的有效释放能量的增大、震源距离的减小与横波能量占比的增大会使得巷道冲击风险性随之增大;震动事件发生角影响着巷道冲击风险性,当动载事件发生在强风险区与次强风险区时,微小的动载事件也极易诱发冲击地压,巷道冲击风险性较高;当动载事件发生在弱风险区时,较大的动载事件也不易引起冲击地压,巷道的冲击风险性较低。

心理韧性缓冲压力生活事件与青少年学业倦怠之间的非线性关系

压力生活事件对青少年的适应性发展具有潜在危害。本研究聚焦于学业倦怠,进一步探索压力生活事件与学业倦怠不同维度之间的关系,以及心理韧性的潜在缓冲作用。基于对3309名青少年的有效调查数据,本研究发现:(1)压力生活事件与青少年学业倦怠的消极核心维度之间具有非线性关系,随着压力生活事件的累积,学业倦怠水平增加的速度由快变慢,表现为饱和模型;(2)心理韧性可以充当缓冲性保护机制,相较于低心理韧性个体,对高心理韧性个体而言,压力生活事件与学业倦怠之间的非线性关系减弱,随着压力生活事件的累积,心理韧性的缓冲性效应显现出来;心理韧性无法调节压力生活事件与学业效能之间的非线性关系。研究结果支持饱和模型而非门槛模型,也为韧性分析框架下不同类型适应指标的区分提供了证据。

质量控制小组管理在手术室护理管理中的应用效果

目的:观察质量控制小组管理在手术室护理管理中的应用效果。方法:选取2020年5月至2021年5月该院50名手术室护理人员为对照组,实施常规护理管理;选取2021年6月至2022年6月该院50名手术室护理人员为观察组,实施质量控制小组管理。比较两组管理前后护理管理质量、质量控制标准、工作压力评分,以及不良事件发生率。结果:管理后,观察组护理管理质量评分和护理文书书写、操作规范、器械物品管理等质量控制标准评分均高于对照组,差异有统计学意义(P<0.05);管理后,观察组专业工作、患者护理等工作压力评分均低于对照组,差异有统计学意义(P<0.05);观察组不良事件发生率为2.00%(1/50),低于对照组的16.00%(8/50),差异有统计学意义(P<0.05)。结论:质量控制小组管理应用于手术室护理管理可提高护理管理质量、质量控制标准评分,降低工作压力评分和不良事件发生率,效果优于常规护理管理。

压力性生活事件与初中生手机依赖:心理安全感的中介作用与父母低头行为的调节作用

目的探讨心理安全感在压力性生活事件与手机依赖之间的中介作用,以及父母低头行为在其中的调节作用。方法采用手机依赖指数量表、青少年自评生活事件量表、安全感量表和父母低头行为量表对944名初中生进行施测。对相关数据进行统计学分析。结果压力性生活事件、心理安全感、父母低头行为和手机依赖,两两之间均存在显著相关性。心理安全感在压力性生活事件与手机依赖之间的中介效应显著;父母低头行为在“压力性生活事件→心理安全感”和“心理安全感→手机依赖”的路径中存在显著的调节效应。结论压力性生活事件通过降低心理安全感使初中生手机依赖的风险增高。父母低头行为在压力性生活事件对心理安全感以及心理安全感对手机依赖的影响中起调节作用。

应激性高血糖比值对急性心肌梗死患者院内不良预后的影响

目的探讨应激性高血糖比值(stress hyperglycemia ratio,SHR)对急性心肌梗死(acute myocardial infarction,AMI)患者院内主要不良心血管事件(major adverse cardiovascular events,MACEs)的预测价值。方法回顾性分析2022年1月至2022年12月在首都医科大学附属北京同仁医院心血管中心住院,资料完整的AMI患者共442例。根据入院测得的第一个静脉随机血糖(admission blood glucose,ABG)和糖化血红蛋白(glycosylated hemoglobin,HbA1c)值计算得出SHR。根据是否发生院内MACEs分为MACEs组(n=79)和非MACEs组(n=363)。采用多因素Logistic回归分析探讨AMI患者院内MACEs发生的危险因素。应用受试者工作特征(receiver operating characteristic,ROC)曲线评估SHR对院内MACEs发生的预测价值。结果院内MACEs组的SHR显著高于非MACEs组(1.30±0.44 vs 1.15±0.17,P<0.001)。多因素Logistic回归分析中,SHR是AMI患者院内MACEs发生的危险因素(OR=2.69,95%CI:1.26~5.73,P=0.011)。ROC曲线分析结果显示,SHR对AMI患者院内MACEs有预测价值(AUC=0.63,95%CI:0.57~0.70,P<0.001),最佳截断值为1.29,预测价值高于HbA1c(P=0.011)。结论SHR是AMI患者院内MACEs发生的危险因素,对院内MACEs有预测价值,最佳截断值为1.29,优于HbA1c。

Injectable treatments for female stress urinary incontinence

The use of injectable agents for the treatment of stress urinary incontinence(SUI)is an option for female patients who are unwilling to undergo surgery,or have concurrent conditions or diseases that render surgical treatment unsuitable.To be effective for SUI,an injectable agent must be nonimmunogenic,hypoallergenic,biocompatible,permanent,nonerosive,nonmigratory and painless.It must also heal with minimal fibrosis,possess a long-term bulking effect,and be easily stored and handled.Glutaraldehyde cross-linked bovine collagen(Contigen),silicone polymers(Macroplastique),Durasphere,calcium hydroxyapatite(Coaptite),polyacrylamide hydrogel(Aquamid,Bulkamid),Permacol,and stem cell therapy have been used as injectable agents.Patients must be informed that treatment with injectable agents is not as effective as surgical treatment,and that such agents might necessitate additional and repeated administrations in order to achieve the desired therapeutic effect.

社区精神分裂症患者负性生活事件与失眠的关系:精神病性症状和抑郁的作用路径

背景失眠是精神分裂症患者的常见症状。患者经历的负性生活事件、精神病性症状以及抑郁均可能影响失眠。但在社区精神分裂症患者中,四者的关系尚需进一步探讨。目的探讨负性生活事件对社区精神分裂症患者失眠的影响以及精神病性症状与抑郁的作用路径,以期为社区精神分裂症患者失眠的干预提供参考。方法于2023年4月—6月,纳入四川省成都市48个社区卫生服务中心在管的、符合《国际疾病分类(第10版)》(ICD)精神分裂症诊断标准的1105例患者。采用10项负性生活事件(SLEs)、阿斯森失眠量表(AIS)、精神病筛查问卷(PSQ)、患者健康问卷抑郁量表(PHQ-9)进行评定。采用Spearman相关分析考查各量表评分之间的相关性,采用Smart PLS 4.0构建中介模型,采用偏最小二乘法和Bootstrap法检验中介效应。结果检出332例(30.05%)社区精神分裂症患者存在失眠。精神分裂症患者AIS评分与SLEs评分、PSQ评分、PHQ-9评分均呈正相关(r=0.165、0.322、0.554,P均<0.01)。精神病性症状和抑郁可能是社区精神分裂症患者负性生活事件与失眠之间的独立作用路径,间接效应值分别为0.102、0.372,效应量分别为10.46%、38.15%。精神病性症状和抑郁可能是社区精神分裂症患者负性生活事件与失眠之间的链式作用路径,间接效应值为0.190,效应量为19.49%。结论社区精神分裂症患者的负性生活事件可以直接影响失眠,也可以通过精神病性症状和抑郁的独立或链式作用路径影响失眠。

精神分裂症患者的负性生活事件与复发:社会支持的调节作用

目的探讨精神分裂症患者负性生活事件、复发与社会支持之间的关系,以及社会支持在负性生活事件与复发之间的调节作用。方法采用便利抽样法,抽取宁夏精神卫生中心门诊就诊的215例精神分裂症患者。采用社会再适应评定量表(SRRS)、社会支持评定量表(SSRS)、简明精神病评定量表(BPRS)、临床总体印象-严重程度量表(CGI-S)、Morisky药物依从性量表-8(MMAS-8)分别对负性生活事件、社会支持、复发、疾病严重程度和药物依从性进行测量。采用Spearman相关分析探讨负性生活事件、复发和社会支持之间的相关性,采用二元Logistic回归分析探讨一般资料、负性生活事件、社会支持对复发的影响,采用SPSS PROCESS 3.4探讨社会支持对负性生活事件与复发的调节作用。结果负性生活事件与复发呈正相关(P<0.01),主观社会支持、客观社会支持和社会支持均与复发呈负相关(P均<0.05)。主观社会支持在负性生活事件和复发之间的调节作用显著(P<0.01)。结论负性生活事件和社会支持均与精神分裂症复发密切相关,主观社会支持在负性生活事件和复发之间起到调节作用。

应激生活事件和社会支持对大学生抑郁风险预警阈值研究

目的:抑郁是青少年最常见的情绪问题。其中,近期应激和社会支持是影响大学生抑郁的关键危险性因素和保护性因素,本研究探索这两个关键因素与大学生抑郁关系中可能存在的阈值效应,以期为提升抑郁风险预测的精准性和有效性,以及发展抑郁风险预警系统提供科学依据。方法:整群抽取我国中部H省3所地方普通本科高校2018-2022年入学的14043名本科生进行调查研究。采用SPSS 26.0对数据进行描述性统计分析、相关分析和线性回归分析,并采用R3.5.2进行分段回归模型(PRM)探索应激生活事件和社会支持对大学生抑郁的预测阈值。结果:①应激生活事件、社会支持与抑郁之间存在显著的两两相关,其中,社会支持与应激生活事件、抑郁存在显著的负相关(P<0.01),应激生活事件与抑郁存在显著的正相关(P<0.01);②应激生活事件的阈值达到42.055后,应激生活事件对抑郁水平的诱发作用愈发显著。而社会支持水平的阈值达到18.318后,社会支持对抑郁水平的抑制作用受到削弱;③根据应激生活事件和社会支持对抑郁的阈值效应可将大学生群体分为4组,高应激生活事件低社会支持组和高应激生活事件高社会支持组的大学生抑郁水平显著高于低应激生活事件低社会支持组和低应激生活事件高社会支持组(P<0.05),且高应激生活事件低社会支持组学生的抑郁水平又显著高于高应激生活事件高社会支持组学生(P<0.05);④4个组别的大学生在性别上的分布也存在显著差异(χ^(2)=129.014,P<0.001),高应激生活事件低社会支持组的男生占比(43.7%)明显高于总体样本中男生的比例(30.1%)。结论:应激生活事件、社会支持与大学生抑郁之间存在阈值效应,根据阈值效应分类的高应激生活事件低社会支持组大学生的抑郁水平更为严重;应激生活事件低于42.055阈值水平,社会支持高于18.318的阈值时,大学生的抑郁情绪会得到明显缓解。

300 MeV质子重离子加速器及电子器件单粒子效应试验研究

300 MeV质子重离子加速器主要用于模拟空间环境中高能粒子辐照,探索高能粒子与材料、器件以及生命体的相互作用机理。该加速器主要由离子源、直线加速器、注入线、同步加速器、引出线和3个实验终端组成。自2022年11月验收以来,该加速器已完成质子束、氦束、碳束、氪束、钽束、铋束、铀束等离子束的调试,相继开展了材料、电子器件、农作物种子、微生物、小鼠等样品的辐照试验,成为基础研究的实验平台。在基于该加速器的辐照试验平台中,开展了国产SiC功率MOSFET器件单粒子效应研究。300 MeV质子重离子加速器产生能量为1864.3 MeV的^(181)Ta^(31+)离子束,在经过钛窗和空气中传输后,达到SiC表面时LET值为80.7 MeV·cm^(2)·mg^(-1)。通过在SiC功率MOSFET器件漏极上施加不同偏置电压,对栅极和漏极泄漏电流检测分析,获取了在不同偏置条件下SiC MOSFET器件的漏电退化行为。

维持性血液透析患者不同初始剂量静脉铁剂治疗前后炎症、氧化应激的变化及对主要不良心血管事件的影响

目的探讨维持性血液透析(MHD)患者应用不同初始剂量静脉铁剂治疗前后炎症、氧化应激的变化及对主要不良心血管事件(MACE)的预测价值。方法回顾性分析2017年8月至2019年8月在秦皇岛市第一医院血液透析室行MHD治疗的158例患者的临床资料,根据初始静脉铁剂用量的不同分成高剂量组(每月400 mg蔗糖铁,78例)和低剂量组(每月200 mg蔗糖铁,80例)。两组用药2.5个月后所有患者均1次/2周静脉滴注100 mg蔗糖铁,维持此方案24个月以上。比较两组治疗前、治疗12个月及24个月血红蛋白(Hb)、血清铁蛋白(SF)、转铁蛋白饱和度(TSAT)、炎症因子[C-反应蛋白(CRP)、白细胞介素6(IL-6)、肿瘤坏死因子-α(TNF-α)]及氧化应激因子[超氧化物歧化酶(SOD)、丙二醛(MDA)、髓过氧化物酶(MPO)]指标,观察两组3年内MACE发生情况,并通过ROC分析有关指标对MACE发生的预测价值。结果治疗12个月及24个月两组Hb、SF、TSAT水平及血清CRP、IL-6、TNF-α、MDA、MPO水平均较治疗前增高差异有统计学意义(P<0.05),血清SOD水平均较治疗前降低差异有统计学意义(P<0.05)。治疗24个月,两组Hb、SF、TSAT水平及血清CRP、IL-6、TNF-α、MDA、MPO水平均较治疗12个月增高,血清SOD水平均较治疗12个月降低,差异有统计学意义(P<0.05)。高剂量组MACE发生率与低剂量组比较差异无统计学意义(χ^(2)=0.396,P>0.05)。MACE组血清IL-6、MDA水平高于非MACE组,差异有统计学意义(t=5.352、8.584,P<0.05)。MACE组血清SOD水平低于非MACE组,差异有统计学意义(t=2.467,P<0.05)。血清IL-6、SOD、MDA水平预测MHD患者发生MACE的ROC曲线下面积分别为0.741、0.691、0.887,敏感度分别为57.80%、64.40%、84.40%,特异度分别为81.40%、69.00%、79.60%。结论静脉铁剂200 mg/月和400 mg/月两种给药方法均可有效纠正MHD患者铁缺乏,均加重患者炎症及氧化应激状况;血清IL-6、SOD、MDA水平可预测MHD患者MACE的发生。