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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

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World Journal of Emergency Medicine 2023年第2期14卷 112-121页

作者： Bao-tao Huang yi-heng Cheng Bo-sen yang yi-ke Zhang Fang-yang Huang Yong Peng Xiao-bo Pu Mao Chen Department of Cardiology West China HospitalSichuan UniversityChengdu 610041China

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 ***: 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 ***: 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 ***: 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.

关键词： Pressure injuries Left ventricular ejection fraction Death Geriatrics Myocardial infarction

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磁场下碳化物析出的热力学机制

原子与分子物理学报 2025年第4期42卷 121-130页

作者：廖已莹侯廷平杨雨豪郑一航于涛刘伍明吴开明武汉科技大学理学院武汉430081 冶金工业过程系统科学湖北省重点实验室武汉430081 省部共建耐火材料与冶金国家重点实验室武汉430081 江汉大学光电材料与技术学院光电化学材料与器件教育部重点实验室武汉430056 中国科学院物理研究所北京100190

钢中碳化物的形成主要由合金元素的种类以及含量的决定,碳化物对钢铁材料的显微组织形态和力学性能有重要影响.磁场是影响碳化物析出规律发生改变的重要因素之一.以常见的碳化物M_(6)C(M=Fe,Mo)作为研究对象,利用第一性原理计算η-Fe_(... 详细信息

钢中碳化物的形成主要由合金元素的种类以及含量的决定,碳化物对钢铁材料的显微组织形态和力学性能有重要影响.磁场是影响碳化物析出规律发生改变的重要因素之一.以常见的碳化物M_(6)C(M=Fe,Mo)作为研究对象,利用第一性原理计算η-Fe_(2)C、Fe_(3)C、Fe_(2)Mo_(4)C、Fe_(3)Mo_(3)C-Ⅰ、Fe_(3)Mo_(3)C-Ⅱ和Fe_(4)Mo_(2)C等合金碳化物的磁矩,计算结果表明其中Fe_(4)Mo_(2)C的磁矩最大,达到了7.04μB.磁矩不仅由碳化物晶胞中Fe原子个数有关,还与Fe Wyckoff占位紧密相关.通过模拟计算碳化物的磁致磁热熔、磁熵、磁焓和磁自由能,从热力学角度对各碳化物进行分析,结果表明磁场会使碳化物的磁致磁热熔和磁熵增加;强磁场会降低M_(6)C的磁自由能进而提高其稳定性.此工作为研究核聚变材料磁性能提供理论基础和技术参考.

关键词：磁场碳化物析出相热力学机制

Mechanism of persistent hyperalgesia in neuropathic pain caused by chronic constriction injury

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Neural Regeneration Research 2019年第6期14卷 1091-1098页

作者： Qin-yi Chen Chao-yang Tan yang Wang Ke-tao Ma Li Li Jun-Qiang Si Department of Anesthesiology First Affiliated Hospital of Shihezi UniversityShihezi Department of Physiology Medical College of Shihezi UniversityShihezi Key Laboratory of Xinjiang Endemic and Ethnic Disease Shihezi University School of MedicineShihezi Department of Neurobiology Tongji Medical CollegeHuazhong University of Science and Technology

Transmembrane member 16 A(TMEM16 A) is involved in many physiological functions, such as epithelial secretion, sensory conduction, nociception, control of neuronal excitability, and regulation of smooth muscle contraction, and may be important in peripheral pain transmission. To explore the role of TMEM16 A in the persistent hyperalgesia that results from chronic constriction injury-induced neuropathic pain, a rat model of the condition was established by ligating the left sciatic nerve. A TMEM16 A selective antagonist(10 μg T16 Ainh-A01) was intrathecally injected at L5–6. For measurement of thermal hyperalgesia, the drug was administered once at 14 days and thermal withdrawal latency was recorded with an analgesia meter. For measurement of other indexes, the drug was administered at 12 days,once every 6 hours, totally five times. The measurements were performed at 14 days. Western blot assay was conducted to analyze TMEM16 A expression in the L4–6 dorsal root ganglion. Immunofluorescence staining was used to detect the immunoreactivity of TMEM16 A in the L4–6 dorsal root ganglion on the injured side. Patch clamp was used to detect electrophysiological changes in the neurons in the L4–6 dorsal root ganglion. Our results demonstrated that thermal withdrawal latency was shortened in the model rats compared with control ***, TMEM16 A expression and the number of TMEM16 A positive cells in the L4–6 dorsal root ganglion were higher in the model rats, which induced excitation of the neurons in the L4–6 dorsal root ganglion. These findings were inhibited by T16 Ainh-A01 and confirm that TMEM16 A plays a key role in persistent chronic constriction injury-induced hyperalgesia. Thus, inhibiting TMEM16 A might be a novel pharmacological intervention for neuropathic pain. All experimental protocols were approved by the Animal Ethics Committee at the First Affiliated Hospital of Shihezi University School of Medicine, China(approval No. A2017-170-01) on February 27

关键词： nerve regeneration TMEM16A calcium-activated chloride channels T16Ainh-A01 neuropathic pain dorsal root ganglia hyperalgesia action potential rheobase chronic constriction injury peripheral nerve injury neural regeneration

Effect of Al on Expansion Behavior of Mg–Al Alloys During Solidification

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Acta Metallurgica Sinica(English Letters) 2019年第5期32卷 559-565页

作者： yi Meng Jian Sun Lei-Gang Cao Yue yang Hai-tao Zhang Jian-Zhong Cui School of Mechanical and Materials Engineering North China University of Technology Key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern University

The cooling curves and the change of contraction/expansion during solidification and cooling were tested by using a selfmade device which could achieve the one-dimensional contraction instead of three-dimensional contraction of the ***, the effects of Al content(0, 1.1, 3, 5, 10, 12.9, 15, 17, 19, 22, 24 and 30 wt%) on the thermal contraction/expansion of the binary Mg-Al as-cast alloys during solidification were obtained. The results showed that expanding instead of contraction was present in Mg-Al alloys with the addition of 0-30 wt% Al during solidification. The values of expansion significantly increased at first and then decreased with the increase in Al content. And the maximum expansion ratio of 0.44%(maximum expansion value: 0.841 mm) was present in the Mg-15 wt% Al alloy. Contraction instead of expansion occurred once the temperature drops to the temperature corresponding to the expansion value in total, indicating the occurrence of a continuous expansion during the solidification process in mushy zone for the Mg alloys with Al addition of 5-30 wt%. The expansion value in total consisted of two parts: the expansions occurring in the liquid-phase zone and mushy zone. The expansion in liquid zone was present in every Mg-Al alloy, and it contributed to the most proportion of the total expansion value when the Al content in Mg-Al alloy was lower than 10 wt% or higher than 22 wt%. However, the total expansion value was mainly determined by the solidification behavior in mushy zone when the Al content was among 10-22 wt% in Mg-Al alloys.

关键词： Solidification Mg alloys Al content Expansion

Preparation of a cationic azobenzene dye-montmorillonite intercalation compound and its photochemical behavior

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Journal of University of Science and Technology Beijing 2006年第3期13卷 281-286页

作者： tao Wan yi Yuan Wenqiong He College of Materials and Chemistry ＆ Chemical Engineering Chengdu University of Technology Chengdu 610059 China

Montmorillonite/cationic azobenzene dye （GTL） intercalation compounds were prepared by the conventional ion exchange method. As compared with that of pure GTL, the thermal stability of the intercalated GTL was greatly enhanced, and the absorption band corresponding to azobenzene group in intercalated GTL shifted towards a longer wavelength by 55 nm, which could be ascribed to the strong conjugation of GTL supramolecular order structure （J cluster） confined in a nanoscale space of montmorillonite interlayer gallery. The microstructures of the resulting intercalation compounds could be successfully controlled by varying the amount of dye loaded as evidenced by the basal spacing of the intercalation compounds. The intercalated azo dye in the montmorillonite interlayer space exhibited reversible trans-to-cis photoisomerization and thermal cis-to-trans reaction. FTIR proved the successful intercalation of GTL into the silicate layer.

关键词： Na-montmorillonite azobenzene intercalation photoisomerization

Using FEM to predict tree motion in a wind field

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第7期9卷 907-915页

作者： Xiao-yi HU Wei-ming tao yi-mu GUO Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China School of Engineering Zhejiang Forestry University Hangzhou 311300 China

In this paper we propose a finite element(FE) simulation method to predict tree motion in a wind field. Two FE tree models were investigated:One model was generated based on a realistic nature-looking geometric tree model,and the other was a symmetric model to investigate the influence of asymmetric material properties on tree motion. The vortex-induced vibration(VIV) theory is introduced to estimate the fluctuating wind force being exerted on tree stems and the fluid-structure interaction(FSI) analysis is also included in the simulation. The results indicate that asymmetric material properties result in the crosswind displacement of the investigated node and the main swaying direction deviation. The simulation reveals that under wind loading,a tree with leaves has much larger swaying amplitude along the wind direction and longer swaying period than a tree without leaves. However,the crosswind swaying amplitude is mainly due to branch interaction. The numerical simulation proved that the inter-action of tree branches can prevent dangerous swaying motion developing.

关键词： Finite element method (FEM) Fluid-structure interaction (FSI) Vortex-induced vibration (VIV) Asymmetric Wind field

Roasting and leaching behaviors of vanadium and chromium in calcification roasting–acid leaching of high-chromium vanadium slag

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International Journal of Minerals,Metallurgy and Materials 2018年第5期25卷 515-526页

作者： Jing Wen tao Jiang Mi Zhou Hui-yang Gao Jia-yi Liu Xiang-xin Xue School of Metallurgy Northeastern University Liaoning Key Laboratory for Recycling Science of Metallurgical Resources

Calcification roasting–acid leaching of high-chromium vanadium slag(HCVS)was conducted to elucidate the roasting and leaching behaviors of vanadium and *** effects of the purity of Ca O,molar ratio between Ca O and V_2O_5(n(Ca O)/n(V_2O_5)),roasting temperature,holding time,and the heating rate used in the oxidation–calcification processes were *** roasting process and mechanism were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),and thermogravimetry–differential scanning calorimetry(TG–DSC).The results show that most of vanadium reacted with Ca O to generate calcium vanadates and transferred into the leaching liquid,whereas almost all of the chromium remained in the leaching residue in the form of(Fe_(0.6)Cr_(0.4))_2O_*** trends of the vanadium and chromium leaching ratios were always opposite because of the competitive reactions of oxidation and calcification between vanadium and chromium with Ca ***,Ca O was more likely to combine with vanadium,as further confirmed by thermodynamic *** the HCVS with Ca O added in an n(Ca O)/n(V_2O_5)ratio of 0.5 was roasted in an air atmosphere at a heating rate of 10°C/min from room temperature to 950°C and maintained at this temperature for 60 min,the leaching ratios of vanadium and chromium reached91.14%and 0.49%,respectively;thus,efficient extraction of vanadium from HCVS was achieved and the leaching residue could be used as a new raw material for the extraction of ***,the oxidation and calcification reactions of the spinel phases occurred at 592and 630°C for n(Ca O)/n(V_2O_5)ratios of 0.5 and 5,respectively.

关键词： high-chromium vanadium slag calcification roasting roasting behaviors leaching behaviors vanadium extraction

Study on moving target detection to passive radar based on FM broadcast transmitter

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Journal of Systems Engineering and Electronics 2007年第3期18卷 462-468页

作者： Zhu Jiabing tao Liang Hong yi Education Ministry Key Lab of Intelligent Computing and Signal Processing Anhui Univ. Hefei 230039 P. R. China Inst. of Signal Processing East China Research Inst. of Electronic Engineering Hefei 230031 P. R. China

Target detection by a noncooperative illuminator is a topic of general interest in the electronic warfare field. First of all, direct-path interference （DPI） suppression which is the technique of bottleneck of moving target detection by a noncooperative frequency modulation（FM） broadcast transmitter is analyzed in this article; Secondly, a space-time-frequency domain synthetic solution to this problem is introduced： Adaptive nulling array processing is considered in the space domain, DPI cancellation based on adaptive fractional delay interpolation （AFDI） technique is used in planned time domain, and long-time coherent integration is utilized in the frequency domain; Finaily, an experimental system is planned by considering FM broadcast transmitter as a noncooperative illuminator, Simulation results by real collected data show that the proposed method has a better performance of moving target detection.

关键词： passive radar direct path interference adaptive beamforming adaptive fractional delay interpolation,long-time coherent integration.

A Heuristic Approach for Context-Aware Recommendation Using Rough Set Theory

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Chinese Journal of Electronics 2018年第3期27卷 500-506页

作者： HE Ming DONG tao LIU yi College of Computer Science Beijing University of Technology

Context-aware recommender systems, aiming to further improve performance accuracy and user satisfaction by fully utilizing contextual information, have recently become one of the hottest topics in the domain of recommender systems. However, not all contextual information might be relevant or useful for recommendation purposes, and little work has been done on measuring how important the contextual information for *** propose a heuristic optimization algorithm based on rough set theory and collaborative filtering to using contextual information more efficiently for boosting recommendation. Our approach involves three processes. First, significant attributes to represent contextual information are extracted and measured to identify recommended items using rough set theory. Second, the user similarity is evaluated in a target context consideration. Third, collaborative filtering is applied to recommend appropriate *** perform an empirical comparison of three approaches on two real-world data sets. The experimental results show that the proposed approach generates more accurate predictions.

关键词： Recommendation Context Context-aware recommendation Collaborative filtering Rough set