Epicardial adipose tissue in obesity with heart failure with preserved ejection fraction: Cardiovascular magnetic resonance biomarker study

BACKGROUND Obesity has become a serious public health issue,significantly elevating the risk of various complications.It is a well-established contributor to Heart failure with preserved ejection fraction(HFpEF).Evaluating HFpEF in obesity is crucial.Epicardial adipose tissue(EAT)has emerged as a valuable tool for validating prognostic biomarkers and guiding treatment targets.Hence,assessing EAT is of paramount importance.Cardiovascular magnetic resonance(CMR)imaging is acknowledged as the gold standard for analyzing cardiac function and mor-phology.We hope to use CMR to assess EAT as a bioimaging marker to evaluate HFpEF in obese patients.AIM To assess the diagnostic utility of CMR for evaluating heart failure with preserved ejection fraction[HFpEF;left ventricular(LV)ejection fraction≥50%]by measuring the epicardial adipose tissue(EAT)volumes and EAT mass in obese patients.METHODS Sixty-two obese patients were divided into two groups for a case-control study based on whether or not they had heart failure with HFpEF.The two groups were defined as HFpEF+and HFpEF-.LV geometry,global systolic function,EAT volumes and EAT mass of all subjects were obtained using cine magnetic resonance sequences.RESULTS Forty-five patients of HFpEF-group and seventeen patients of HFpEF+group were included.LV mass index(g/m2)of HFpEF+group was higher than HFpEF-group(P<0.05).In HFpEF+group,EAT volumes,EAT volume index,EAT mass,EAT mass index and the ratio of EAT/[left atrial(LA)left-right(LR)diameter]were higher compared to HFpEF-group(P<0.05).In multivariate analysis,Higher EAT/LA LR diameter ratio was associated with higher odds ratio of HFpEF.CONCLUSION EAT/LA LR diameter ratio is highly associated with HFpEF in obese patients.It is plausible that there may be utility in CMR for assessing obese patients for HFpEF using EAT/LA LR diameter ratio as a diagnostic biomarker.Further prospective studies,are needed to validate these proof-of-concept findings.

Statistical Study of the Geoeffectivity of Halo Coronal Mass Ejections Associated with X-Class Flares during Solar Cycles 23 and 24

By analysing a long series of data (1996-2019), we show that solar cycle 23 was more marked by violent solar flares and coronal mass ejections (CMEs) compared to solar cycle 24. In particular, the halo coronal mass ejections associated with X-class flares appear to be among the most energetic events in solar activity given the size of the flares, the speed of the CMEs and the intense geomagnetic storms they produce. Out of eighty-six (86) X-class halo CMEs, thirty-seven (37) or 43% are highly geoeffective;twenty-four (24) or approximately 28% are moderately geoeffective and twenty-five (25) or 29% are not geoeffective. Over the two solar cycles (1996 to 2019), 71% of storms were geoeffective and 29% were not. For solar cycle 23, about 78% of storms were geoeffective, while for solar cycle 24, about 56% were geoeffective. For the statistical study based on speed, 85 halo CMEs associated with X-class flares were selected because the CME of 6 December 2006 has no recorded speed value. For both solar cycles, 75.29% of the halo CMEs associated with X-class flares have a speed greater than 1000 km/s. The study showed that 42.18% of halo (X) CMEs with speeds above 1000 km/s could cause intense geomagnetic disturbances. These results show the contribution (in terms of speed) of each class of halo (X) CMEs to the perturbation of the Earth’s magnetic field. Coronal mass ejections then become one of the key indicators of solar activity, especially as they affect the Earth.

社保缴费与小微企业产品技术创新关系研究——基于CMES数据调查的实证分析

本文基于中国小微企业调查数据,实证分析社保缴费对小微企业产品技术创新的影响。结果表明:(1)社保缴费能够促进小微企业的产品技术创新,社保缴费规模越大,小微企业的产品技术创新程度越高;(2)社保缴费对小微企业产品技术创新的作用存在地区差异,对东部地区小微企业的产品技术创新作用显著,对中西部地区的小微企业作用不显著;(3)社保缴费与规模对产品技术创新的作用存在企业主学历差异,企业主学历为低学历组的小微企业,社保缴费与规模对产品技术创新的作用显著,高学历组作用不显著。

Health-related quality of life among congestive heart failure patients with preserved and reduced ejection fraction

Objective:To determine factors that affect the health-related quality of life(HRQOL)of congestive heart failure(CHF)patients with preserved and reduced ejection fraction.Methods:A cross-sectional study design was used for this study.The stratified random sampling was applied for each subgroup.HRQOL was measured with the Minnesota Living with Hear t Failure Questionnaire.The data were analyzed using chi-square,Spearman's correlation analysis,and independent t-test.Results:A number of 67 respondents participated in the recent study.The total mean scores of HRQOL were significantly different(P=0.001)between heart failure(HF)patients with reduced and preserved ejection fractions,41.07±7.54 and 54.97±4.36,respectively.It related with the physical(mean±standard deviation[SD]=10.4±2.14;t=-10.08,95%CI=-12.46 to-8.34;P-value=0.001)and psychological(mean±SD=3.5±0.5;t=-6.68,95%CI=-4.55 to-2.45;P-value=0.001)domain.Strong correlation was found between age(r=-0.898,P<0.05),NYHA functional classes(r=-0.858,P<0.01),duration of HF(r=-0.807,P<0.01),family support(r=0.927,P<0.01),and quality of life(Qo L).Conclusions:HRQOL in HF patients with reduced ejection fraction was higher than in those with preserved ejection fraction.Family suppor t is a fur ther determinant factor that has a positive correlation to the Qo L.

On Cosmic Ray and Geomagnetic Response to Coronal Mass Ejections （CMEs）

A catalogue of type II bursts and the associated coronal mass ejections （CMEs） observed by the solar and heliospheric observatory （SOHO） mission is used to select the twenty three CMEs events with CME speed equal to and less than 450 km/sec （i.e., less than and equal to the average solar wind speed） during 1997-2008. Our observational results clearly indicate that even slow speed CMEs are capable to produce the cosmic ray and geomagnetic disturbances on day to day basis. The depression in cosmic ray intensity is larger three days after the arrival of the CMEs along with the maximum disturbance in geomagnetic activity on the same day （i.e., after three days from the arrival of CMEs）. Fluctuations in cosmic ray intensity and the geomagnetic activity are also observed before the arrival of the CMEs.

The influence of pressure injury risk on the association between left ventricular ejection fraction and all-cause mortality in patients with acute myocardial infarction 80 years or older

BACKGROUND: We aimed to investigate whether the pressure injury risk mediates the association of left ventricular ejection fraction(LVEF) with all-cause death in patients with acute myocardial infarction(AMI) aged 80 years or older.METHODS: This retrospective cohort study included 677 patients with AMI aged 80 years or older from a tertiary-level hospital. Pressure injury risk was assessed using the Braden scale at admission, and three risk groups(low/minimal, intermediate, high) were defined according to the overall score of six different variables. LVEF was measured during the index hospitalization for AMI. All-cause death after hospital discharge was the primary outcome.RESULTS: Over a median follow-up period of 1,176 d(interquartile range [IQR], 722–1,900 d), 226(33.4%) patients died. Multivariate Cox regression analysis showed that reduced LVEF was associated with an increased risk of all-cause death only in the high-risk group of pressure injury(adjusted hazard ratios [HR]=1.81, 95% confidence interval [CI]: 1.03–3.20;P=0.040), but not in the low/minimal-(adjusted HR=1.29, 95%CI: 0.80–2.11;P=0.299) or intermediate-risk groups(adjusted HR=1.14, 95%CI: 0.65–2.02;P=0.651). Significant interactions were detected between pressure injury risk and LVEF(adjusted P=0.003). The cubic spline with hazard ratio plot revealed a distinct shaped curve relation between LVEF and all-cause death among different pressure injury risk groups.CONCLUSIONS: In older patients with AMI, the risk of pressure injury mediated the association between LVEF and all-cause death. The classification of older patients for both therapy and prognosis assessment appears to be improved by the incorporation of pressure injury risk assessment into AMI care management.

Impact of vericiguat on heart failure with reduced ejection fraction:a review

Introduction:Heart failure is a major public health issue with a prevalence of about 26 million people worldwide.Reduced nitric oxide availability,lower soluble guanylate cyclase(sGC)activity,and decreased cyclic guanosine monophosphate(cGMP)production are the causes of HF's development.Vericiguat prescribed under the brand name Verquvo was approved by U.S.Food and Drug Administration(FDA)in January 2021.It is a novel agent and the first sGC stimulator which helps to treat patients suffering from heart failure with reduced ejection fraction(HFrEF).Objective:The mechanism of action(cGMP pathway)of vericiguat,its clinical trials,its use in the treatment of heart failure,and its possible future aspects in therapeutic recommendations are all covered in this review.It will also raise awareness amongst healthcare professionals about the pharmacokinetic and pharmacodynamic parameters,dosing,administration,and drug-related problems of this new drug.Methods:Various databases for drug review were used in this review like PubMed,Medline,Google scholar,Drug bank,U.s.FDA,Medscape,and European society of cardiology guidelines.A total of 58 articles were screened out of which 39 articles were included in this review.Results:This review discusses vericiguat's mechanism of action(cGMP pathway),clinical studies,application in the treatment of heart failure,and potential future considerations in therapeutic recommendations.It will also educate healthcare professionals about the new drug's pharmacokinetics and pharmacodynamics,dose,administration,and drug-related problems.Conclusion:After hospitalization for HFrEF,the 5-year survival rate is just 25%,and disease morbidity and death are stil significant.As adjunctive therapy for individuals with heart failure and a low ejection fraction,vericiguat has a moderate level of effectiveness.Vericiguat's efficacy as an adjunct therapy to different drugs used to cure HF has to be further investigated.Vericiguat's safety and dosage in patients who have severe renal or hepatic illness need to be studied further.

Targeting epicardial adipose tissue:A potential therapeutic strategy for heart failure with preserved ejection fraction with type 2 diabetes mellitus

Heart failure with preserved ejection fraction(HFpEF)is a heterogeneous syndrome with various comorbidities,multiple cardiac and extracardiac pathophysiologic abnormalities,and diverse phenotypic presentations.Since HFpEF is a heterogeneous disease with different phenotypes,individualized treatment is required.HFpEF with type 2 diabetes mellitus(T2DM)represents a specific phenotype of HFpEF,with about 45%-50% of HFpEF patients suffering from T2DM.Systemic inflammation associated with dysregulated glucose metabolism is a critical pathological mechanism of HFpEF with T2DM,which is intimately related to the expansion and dysfunction(inflammation and hypermetabolic activity)of epicardial adipose tissue(EAT).EAT is well established as a very active endocrine organ that can regulate the pathophysiological processes of HFpEF with T2DM through the paracrine and endocrine mechanisms.Therefore,suppressing abnormal EAT expansion may be a promising therapeutic strategy for HFpEF with T2DM.Although there is no treatment specifically for EAT,lifestyle management,bariatric surgery,and some pharmaceutical interventions(anti-cytokine drugs,statins,proprotein convertase subtilisin/kexin type 9 inhibitors,metformin,glucagon-like peptide-1 receptor agonists,and especially sodium-glucose cotransporter-2 inhibitors)have been shown to attenuate the inflammatory response or expansion of EAT.Importantly,these treatments may be beneficial in improving the clinical symptoms or prognosis of patients with HFpEF.Accordingly,well-designed randomized controlled trials are needed to validate the efficacy of current therapies.In addition,more novel and effective therapies targeting EAT are needed in the future.

适用于大视场CME观测的侧面遮拦式外掩体设计

针对当前中国空间太阳观测任务中大视场日冕仪杂散光抑制需求,提出一种适用于大视场日冕物质抛射(CME)观测的日球层成像仪侧面遮拦式外掩体设计,通过在外掩体上设置多阶挡光环结构,对进入相机视场的衍射光进行抑制。基于菲涅尔-基尔霍夫衍射理论,开展组件抑制能力仿真分析,并探索不同挡光环间距、挡光环阶数、挡光环后截距等参数对于组件性能的影响。通过搭建一种适用于微弱杂散信号的测试系统,应用微光探测器和微光照度计,从图像和数值方面对组件性能进行验证。研究结果表明,经优化后的侧面遮拦式外掩体在十万级洁净度条件下杂散光抑制水平优于10–9,能够满足大视场CME观测的杂散光抑制要求。

The Clinical Association of Left Atrial Function with Left Ventricular Ejection Fraction

The left atrium (LA) has been recognized as a morphophysiological barometer of left ventricular (LV) diastolic dysfunction. Because in the myocardial ischemia cascade where LV diastolic dysfunction often precedes LV systolic dysfunction, the LA which fashions as an early marker of diastolic anomaly, could equally reflect a declining LV function and/or be a good predictor of potential sequelae. We assessed this association of LA function with reduced LV systolic function among hospitalized patients. Among patients with reduced LV ejection fraction, LA passive ejection fraction was lower (0.172 ± 0.12 vs. 0.232 ± 0.14, p = 0.013) whereas LA kinetic energy was higher (6.48 ± 6.3 vs. 4.57 ± 3.5, p = 0.005). Echocardiographic assessment of LA function, therefore, appears correlated with LVEF and could be important when risk stratifying hospitalized patients.

Heterogeneity in cardiorenal protection by Sodium glucose cotransporter 2 inhibitors in heart failure across the ejection fraction strata:Systematic review and meta-analysis

BACKGROUND Gliflozins or Sodium glucose cotransporter 2 inhibitors(SGLT2i)are relatively novel antidiabetic medications that have recently been shown to represent favorable effects on patients’cardiorenal outcomes.However,there is shortage of data on potential disparities in this therapeutic effect across different patient subpopulations.AIM To investigate differential effects of SGLT2i on the cardiorenal outcomes of heart failure patients across left ventricular ejection fraction(LVEF)levels.METHODS Literature was searched systematically for the large randomized double-blind controlled trials with long enough follow up periods reporting cardiovascular and renal outcomes in their patients regarding heart failure status and LVEF levels.Data were then meta-analyzed after stratification of the pooled data across the LVEF strata and New York Heart Associations(NYHA)classifications for heart failure using Stata software version 17.0.RESULTS The literature search returned 13 Large clinical trials and 13 post hoc analysis reports.Meta-analysis of the effects of gliflozins on the primary composite outcome showed no significant difference in efficacy across the heart failure subtypes,but higher efficacy were detected in patient groups at lower NYHA classifications(I2=46%,P=0.02).Meta-analyses across the LVEF stratums revealed that a baseline LVEF lower than 30%was associated with enhanced improvement in the primary composite outcome compared to patients with higher LVEF levels at the borderline statistical significance(HR:0.70,95%CI:0.60 to 0.79 vs 0.81,95%CI:0.75 to 0.87;respectively,P=0.06).Composite renal outcome was improved significantly higher in patients with no heart failure than in heart failure patients with preserved ejection fraction(HFpEF)(HR:0.60,95%CI:0.49 to 0.72 vs 0.94,95%CI:0.74 to 1.13;P=0.04).Acute renal injury occurred significantly less frequently in heart failure patients with reduced ejection fraction who received gliflozins than in HFpEF(HR:0.67,95%CI:51 to 0.82 vs 0.94,95%CI:0.82 to 1.06;P=0.01).Volume depletion was consistently increased in response to SGLT2i in all the subgroups.CONCLUSION Heart failure patients with lower LVEF and lower NYHA sub-classifications were found to be generally more likely to benefit from therapy with gliflozins.Further research are required to identify patient subgroups representing the highest benefits or adverse events in response to SGLT2i.

Interaction between the left ventricular ejection fraction and left ventricular strain and its relationship with coronary stenosis

BACKGROUND Coronary artery stenosis(CAS)is the most common type of heart disease and the leading cause of death in both men and women globally.CAS occurs when the arteries that supply blood to the heart muscle harden and become narrower due to plaque buildup-cholesterol and other material-on their inner walls.As a result,the heart muscle cannot receive the blood or oxygen it needs.Most heart attacks happen when a blood clot suddenly cuts off the hearts'blood supply,causing permanent heart damage.AIM To analyze the relationship between the left ventricular ejection fraction(LVEF),left ventricular strain(LVS),and coronary stenosis.METHODS A total of 190 participants were enrolled in this trail.The control group comprised 93 healthy individuals,and observation group comprised 97 patients with coronary heart disease who were hospitalized between July 2020 and September 2021.Coronary lesions were assessed using the Gensini score,and the LVEF and LVS were measured using magnetic resonance imaging(MRI).The interaction between the LVEF and LVS was examined using a linear regression model.The relationship between LVEF and coronary stenosis was examined using Spearman’s correlation.RESULTS The LVEF of the observation group was lower than that of the control group.The left ventricular end-systolic volume(LVESV)and left ventricular end-diastolic volume(LVEDV)of the observation group were significantly higher than those of the control group(P<0.05).The longitudinal and circumferential strains(LS,CS)of the observation group were significantly higher than those of the control group;however,the radial strain(RS)of the observation group was significantly lower than that of the control group(P<0.05).LVS,LS,and CS were significantly negatively correlated with the LVEF,and RS was positively correlated with the LVEF.There were significant differences in the LVEF,LVESV,and LVEDV of patients with different Gensini scores;the LVEF significantly decreased and the LVESV and LVEDV increased with increasing Gensini scores(P<0.05).In the observation group,the LVEF was negatively correlated and the LVESV and LVEDV were positively correlated with coronary stenosis(P<0.05).CONCLUSION The LVEF measured using MRI is significantly linearly correlated with LVS and negatively correlated with coronary stenosis.

Clinical efficacy of dapagliflozin in the treatment of type 2 diabetes mellitus with heart failure with mildly reduced ejection fraction

Objective:To observe the clinical efficacy of dapagliflozin in the treatment of type 2 diabetes mellitus(T2DM)complicated with heart failure with mildly reduced ejection fraction(HFmrEF,40%≤LVEF<50%).Methods:A total of 84 patients with T2DM complicated with HFmrEF hospitalized in our hospital from October 2019 to October 2021 were selected,and random number table method was used to divide into the control group and the study group each 42 cases.Both groups used basal hypoglycemic and standardized anti-heart failure therapy,and the study group was treated with dapagliflozin simultaneously.Nine months later,the following indexes were compared between the two groups before and after treatment:the cardiac function indicators:N-terminal pro brain natriuretic peptide(NT-proBNP),left ventricular ejection fraction(LVEF);exercise endurance:6-minute walk distance(6MWD),NYHA cardiac function class,the score of the Minnesota living with heart failure questionnaire(MLHFQ)and the incidence of major adverse cardiovascular events(MACE).Results:Nine months later,the two groups showed decreased NT-proBNP level,increased LVEF,prolonged 6MWD,improved NYHA cardiac function grade,decreased MLHFQ score,and statistically significant differences within both groups compared with before treatment(P<0.05),after treatment significant differences were displayed between the two groups(P<0.05).Less patients had MACE events and adverse drug reactions in the study group compared with the control group.Conclusion:Dapagliflozin in the treatment of T2DM patients with HFmrEF can improve cardiac function indicators,improve exercise endurance,improve NYHA cardiac function class,improve patient's quality of life,and reduce the incidence of MACE events,with no obvious side effects.

Therapies for patients with coexisting heart failure with reduced ejection fraction and non-alcoholic fatty liver disease

Heart failure with reduced ejection fraction(HFrEF)and nonalcoholic fatty liver disease(NAFLD)are two common comorbidities that share similar pathophysiological mechanisms.There is a growing interest in the potential of targeted therapies to improve outcomes in patients with coexisting HFrEF and NAFLD.This manuscript reviews current and potential therapies for patients with coexisting HFrEF and NAFLD.Pharmacological therapies,including angiotensinconverting enzyme inhibitors/angiotensin receptor blockers,mineralocorticoids receptor antagonist,and sodium-glucose cotransporter-2 inhibitors,have been shown to reduce fibrosis and fat deposits in the liver.However,there are currently no data showing the beneficial effects of sacubitril/valsartan,ivabradine,hydralazine,isosorbide nitrates,digoxin,or beta blockers on NAFLD in patients with HFrEF.This study highlights the importance of considering HFrEF and NAFLD when developing treatment plans for patients with these comorbidities.Further research is needed in patients with coexisting HFrEF and NAFLD,with an emphasis on novel therapies and the importance of a multidisciplinary approach for managing these complex comorbidities.

不同衰弱评估工具对老年射血分数保留的心力衰竭患者的临床意义

目的比较临床衰弱量表(CFS)、衰弱筛查量表(FRAIL)、衰弱表型量表(Fried)及衰弱指数(FI)四种衰弱评估工具在老年射血分数保留的心力衰竭(HFpEF)患者中的临床意义与价值。方法单中心横断面研究。纳入2021年9月至2023年2月南京医科大学第一附属医院老年心血管科的住院患者190例,其中HFpEF组61例,非HFpEF组129例。分别使用CFS、FRAIL、Fried和FI进行衰弱评估,构建综合衰弱指数(CI)作为“金标准”,比较不同工具间的一致性、敏感度、特异度和受试者工作特征曲线下面积(AUC)。结果与非HFpEF组相比,HFpEF组的年龄、心房颤动比例、N末端B型利钠肽原水平、简版老年抑郁量表(GDS-15)评分更高,吸烟史比例、体质指数、舒张压、握力、简易精神状态评价量表(MMSE)评分、微型营养评估量表(MNA-SF)评分更低(均为P<0.05)。针对同一群体,所使用的衰弱评估工具不同,衰弱的患病率也各不相同;无论使用何种评估工具,HFpEF组中衰弱的患病率均高于非HFpEF组(均为P<0.001)。在整体人群及非HFpEF组中,CFS具有良好的敏感度(98.44%、100.00%,P<0.001)和特异度(91.27%、94.23%,P<0.001),AUC分别为0.960、0.975(P<0.001),与CI之间的一致性高(Kappa值=0.846、0.864,P<0.001);在HFpEF人群中,Fried具有最高的敏感度(100.00%,P<0.001)与可接受的特异度(77.27%,P<0.001),AUC为0.956(P<0.001),与CI之间的一致性最高(Kappa值=0.813,P<0.001)。结论衰弱在老年患者中十分普遍,尤其在HFpEF人群中发生率更高。在老年HFpEF人群中Fried适用性更好,在老年一般人群及非HFpEF人群中CFS更具优势。

射血分数保留心力衰竭研究评述

射血分数保留心力衰竭(heart failure with preserved ejection fraction,HFpEF)是目前心血管领域研究的热点和难点。本文对近20年、尤其是近10年HFpEF相关重要的、具有里程碑式的研究进展进行系统梳理,包括病名的演变、核心发病机制的深入阐释、诊断方法和标准的推陈出新、分类分期分级的更新、治疗的困境和曙光、预后与转归的再认识等。通过对HFpEF过去、现在和未来发展中的重点和难点进行述评,以期为致力于HFpEF研究的同行提供精要简练的参考,为中医药防治HFpEF提供一些启发与思考,推动中西医结合在HFpEF防治中的主体地位。

沙库巴曲缬沙坦对老年射血分数降低心力衰竭患者心脏功能和结构的影响

目的:观察老年射血分数降低型心力衰竭(heart failure with reduced ejection fraction,HFr EF)患者使用沙库巴曲缬沙坦后第3个月的心脏功能及结构的变化。方法:连续性纳入2020年1月至2022年5月,于北京安贞医院住院的173例使用沙库巴曲缬沙坦的老年HFr EF患者,其中男性131例(75.7%),平均年龄为(69.5±7.2)岁。对纳入患者采用超声心动图进行随访。主要观察终点是出院后第3个月的心脏功能及结构的变化,包括LVEF、LVEDD、LVESD、LAD、室间隔厚度、左心室后壁厚度、左心室质量指数。结果:相比于入院时的心功能,使用沙库巴曲缬沙坦第3个月的LVEF明显提高(45.9%vs.37.5%,P<0.01),而LVEDD(56.5 vs.60.2mm,P<0.01)、LVESD(42.5vs.47.6mm,P<0.01)、LAD(49.1 vs.53.0mm,P=0.01)、左心室质量指数(111.3 vs.125.5g/m^(2),P<0.01)均明显降低。在亚组分析中,男性和NHYAⅡ~Ⅲ亚组的患者心脏功能和结构改善更为显著(均P<0.05)。结论:沙库巴曲缬沙坦能够改善老年HFr EF患者的心脏功能和结构。

基于注视特征的多因素飞行冲突探测策略研究

为研究不同空域复杂性条件下的飞行冲突探测策略,设计最小间距(MD)×汇聚角度(CA)×速度特性(SC)的被试内三因素重复测量实验方案,基于马尔科夫链的注视平稳分布概率和兴趣区注视时长分布特征,判断被试所采用的冲突探测策略并分析不同策略下的任务绩效指标。研究结果表明:在汇聚角度较大、最小间距更接近告警间隔的实验场景中,被试多采用距离-速度比(DV)策略;在汇聚角度较小、最小间距较小、航空器速度相同的实验场景中,被试多采用认知运动外推(CME)策略。多数情况下,采用CME策略判断飞行冲突的反应时更短、正确率更高。研究结果可为提高冲突探测的感知和预判能力提供参考。

轴向冷气弹射系统建模及仿真分析

根据轴向冷发射需求,同时避免发射过程对发射平台内部空间的污染,设计了一种以高压氮气为弹射能源的轴向底推式冷弹发射装置。介绍了轴向冷弹发射系统的结构组成、工作原理以及设计要点,并运用理想气体状态方程、质量和能量守恒定律、气体动力学等设计理论与方法,建立了轴向底推式冷气弹射系统的高压室、低压室、阀口气体流动以及导弹运动的数学模型。为提高导弹发射时的分离速度,同时降低发射过载峰值,以建立的数学模型为基础,基于内弹道结构参数,采用VB语言编程,通过仿真计算和分析,研究了气瓶初始压强、气瓶容积、低压室初始容积、电磁阀通径、无阻尼自然频率、阻尼比及活塞(托盘)直径等弹射系统的主要结构参数对产品的分离速度和发射过载的影响,找出了各个结构参数变化对导弹分离参数的影响规律,并对影响规律的机理进行了分析。该研究为弹射系统结构参数的优化提供了理论依据,为同类型轴向冷弹发射装置内弹道设计提供了理论参考和依据。

螺内酯对射血分数轻度降低心力衰竭合并2型糖尿病患者的临床疗效观察及预后研究

目的 探究螺内酯对射血分数轻度降低的心力衰竭合并2型糖尿病患者的临床疗效及预后观察。方法 纳入2019年2月至2022年12月于北京朝阳医院治疗的射血分数轻度降低的心力衰竭合并2型糖尿病患者共409例。所有患者在试验前均未服用过螺内酯,已接受其他心衰标准药物治疗及降糖药物治疗至少半年。通过随机分组将纳入患者分为试验组及对照组,试验组在对照组治疗基础上加用螺内酯10~20 mg/d。比较两组患者治疗前后的糖化血红蛋白(glycated hemoglobin, HbA1c)、体质量指数、血浆N末端B型利钠肽原(NT-proBNP)、左室射血分数(LVEF)、左室舒张末期内径(LVEDD)、舒张期二尖瓣峰值流速与二尖瓣环舒张早期运动峰速度的比值(E/e’)、血清肌酐(Scr)、血清尿酸(SUA)、肌酐清除率(Ccr)、血钾水平等指标的变化,观察治疗相关不良反应、心血管死亡或心衰恶化再住院复合终点事件发生率,评估临床治疗效果。结果 两组患者于治疗前的一般资料比较差异无统计学意义(P>0.05);治疗后试验组患者的HbA1c水平较对照组下降[(7.2±0.5)vs.(7.9±0.7),P<0.05],NT-proBNP水平较对照组降低[(423±155)vs.(640±157),P<0.05];试验组治疗后的心功能及肾功能多项指标的改善情况优于对照组(均P<0.05),心功能Ⅱ~Ⅳ级的试验组患者于治疗期间血钾水平相对稳定(均P>0.05)。治疗后试验组的临床显效率及总有效率高于对照组(均P<0.05),复合终点事件发生率及药物治疗相关不良反应在两组中差异无统计学意义(均P>0.05)。结论 螺内酯有助于射血分数轻度降低的心力衰竭合并2型糖尿病患者的血糖管理,并能进一步改善心脏功能及肾功能,同时具有良好的药物使用安全性。