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A Proof of the Jacobian Conjecture on Global Asymptotic Stability

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Acta Mathematica Sinica,English Series 2001年第1期17卷 119-132页

作者： Peng Nian CheN jian xun he Hua Shu QIN Division of Mathematics China Institute of Metrology Department of Systems Science Xiamen University Institute of Systems Science Academia Sinica

Let f∈C^1(R^2, R^2), f(0)=0. The Jacobian Conjecture states that if for any x∈R^2, the eigenvalues of the Jacobian matrix Df(x) have negative real parts, then the zero solution of the differential equation x=f(x) is... 详细信息

关键词： Plane differential equation Global stability Global injectivity

Development of heart failure risk prediction models based on a multi-marker approach using random forest algorithms

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Chinese Medical Journal 2019年第7期132卷 819-826页

作者： Hui Yuan Xue-Song Fan Yang Jin jian-xun he Yuan Gui Li-Ying Song Yang Song Qi Sun Wei Chen Clinical Laboratory First Affiliated Hospital of Xi'an Jiaotong UniversityXi'anShaanxi 710061China Department of Clinical Laboratory Center Beijing Anzhen HospitalCapital Medical UniversityBeijing Institute of HeartLung and Blood Vessel DiseasesBeijing 100029China

Background:The early identification of heart failure(HF)risk may favorably affect outcomes,and the combination of multiple biomarkers may provide a more comprehensive and valuable means for improving the risk of *** study was conducted to assess the importance of individual cardiac biomarkers creatine kinase MB isoenzyme(CK-MB),B-type natriuretic peptide(BNP),galectin-3(Gal-3)and soluble suppression of tumorigenicity-2(sST2)for HF diagnosis,and the predictive performance of the combination of these four biomarkers was analyzed using random forest ***:A total of 193 participants(80 patients with HF and 113 age-and gender-matched healthy controls)were included from June 2017 to December *** correlation and regression analysis were conducted between cardiac biomarkers and echocardiographic *** accuracy and importance of these predictor variables were assessed using random forest ***:Patients with HF exhibited significantly higher levels of CK-MB,BNP,Gal-3,and *** exhibited a good independent predictive capacity for HF(AUC 0.956).However,CK-MB,sST2,and Gal-3 exhibited a modest diagnostic performance for HF,with an AUC of 0.709,0.711,and 0.777,*** was the most important variable,with a remarkably higher mean decrease accuracy and ***,there was a general increase in predictive performance using the multi-marker model,and the sensitivity,specificity was 91.5%and 96.7%,***:The random forest algorithm provides a robust method to assess the accuracy and importance of predictor *** combination of CK-MB,BNP,Gal-3,and sST2 achieves improvement in prediction accuracy for HF.

关键词： Biomarkers Diagnostic accuracy heart failure Random forests

多中心性颅咽管瘤的MRI表现(附4例报告)

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实用放射学杂志 2003年第9期19卷 849-851页

作者：宋建勋何宁张静兰州医学院第二附属医院放射科兰州医学院第二附属医院放射科甘肃兰州730030

目的　分析多中心性颅咽管瘤的MRI表现 ,提高对本病的认识。方法　 4例经手术及病理证实的多中心性颅咽管瘤 ,术前行MRI平扫及Gd -DTPA增强后MRI成像 ,其中 2例行PDWI成像。结果　多中心性颅咽管瘤的MRI表现为鞍区或鞍上区以实性为主的... 详细信息

目的　分析多中心性颅咽管瘤的MRI表现 ,提高对本病的认识。方法　 4例经手术及病理证实的多中心性颅咽管瘤 ,术前行MRI平扫及Gd -DTPA增强后MRI成像 ,其中 2例行PDWI成像。结果　多中心性颅咽管瘤的MRI表现为鞍区或鞍上区以实性为主的囊实性中心病灶 ,同时在双颞叶、前颅窝底、三脑室前部、桥前池内或尾状核可见多个大小不一的囊性病灶。囊实性病灶在T1WI及T2 WI上分别为低等及高低混杂信号 ;囊性病灶平扫T1WI表现为变化多样的高低信号 ,T2 WI表现为高信号 ,PDWI表现为等及高信号。强化后囊性病灶表现为环状薄壁强化 ,实质性病灶为均匀强化。结论　多中心性颅咽管瘤的生长表现为以鞍区或鞍上区为中心的多点起源的生长特点 ,肿瘤的信号特点与病灶囊实性比例及囊液的成分有关

关键词：颅咽管瘤多中心性磁共振成像

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关于战场无人机航迹规划方法研究

计算机仿真 2017年第4期34卷 105-109页

作者：申舟刘建勋赫志韦谢岩甫空军第一航空学院河南信阳464000

无人机执行任务时对各因素的敏感程度会随战场环境不同而变化,要求航迹能够根据任务需求进行调整。如何使规划航迹与任务需求相匹配是一个难点问题。针对上述问题,根据物理规划理论提出了一种面向任务需求的无人机航迹规划方法。首先利... 详细信息

无人机执行任务时对各因素的敏感程度会随战场环境不同而变化,要求航迹能够根据任务需求进行调整。如何使规划航迹与任务需求相匹配是一个难点问题。针对上述问题,根据物理规划理论提出了一种面向任务需求的无人机航迹规划方法。首先利用物理规划思想,建立航迹规划模型。其次,构建面向任务的航迹评价指标体系,包括构建航迹评价指标体系、设计具有可比性的代价函数以及引入反映任务需求的偏好因子,为航迹搜索提供基础。最后,利用改进的遗传算法实现航迹搜索,可获得不同任务需求下的规划航迹。仿真结果表明,上述方法能够满足不同任务需求,具有一定的可行性。

关键词：航迹规划物理规划遗传算法无人机

Orbifold Gromov–Witten Invariants of Weighted Blow-up at Smooth Points

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Acta Mathematica Sinica,English Series 2015年第5期31卷 825-846页

作者： Wei Qiang he jian xun HU Department of Mathematics Sun Yat-Sen University

In this paper, one considers the change of orbifold Gromov Witten invariants under weighted blow-up at smooth points. Some blow-up formula for Gromov-Witten invariants of sym- pleetic orbifolds is proved. These result... 详细信息

关键词： Gromov-Witten invariant orbifold weighted blow-up

Reaction mechanism between Al_(2)O_(3)–MgO refractory materials and rare earth high-carbon heavy rail steel

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Journal of Iron and Steel Research International 2024年第5期31卷 1153-1163页

作者： Yi Wang Guang-jie Song Ping Shen jian-zhong he Da-xian Zhang jian-xun Fu Center for Advanced Solidification Technology(CAST) School of Materials Science and EngineeringState Key Laboratory of Advanced Special SteelShanghai UniversityShanghai200444China State Key Laboratory of Baiyunebo Rare Earth Resources Research and Comprehensive Utilization Baotou014030Inner MongoliaChina Inner Mongolia Baotou Steel Union Co. Ltd.Baotou014030Inner MongoliaChina

Submerged entry nozzle(SEN)clogging is a major problem affecting the production quality of rare earth steel,and finding a suitable refractory outlet can significantly reduce production *** explore the relationship between refractory composition and interface interaction,unprotected coated Al_(2)O_(3)–MgO refractories and SiO2-coated Al_(2)O_(3)–MgO refractories were added to rare earth high-carbon heavy rail steel under laboratory conditions,and the Al_(2)O_(3)–MgO refractory was found to be more *** results show that,from the epoxy resin side to the refractory side,the contour of the refractory interface reaction layer can be divided into two main layers:an iron-rich reaction layer and an iron-poor reaction *** based on the spherical model suggest that the adhesion force is proportional to the size of the refractory particles and inclusions,and the same result applies to the surface *** the inclusions at a smaller size has a specific effect on alleviating the erosion of *** with the erosion mechanism of Al_(2)O_(3)–MgO refractories,the interface reaction mechanism between Al_(2)O_(3)–MgO refractories and molten steel was proposed,which provides ideas for solving SEN clogging.

关键词： Rare earth high-carbon heavy rail steel Al_(2)O_(3)-MgO refractory Adhesion Surface tension Interface interaction

Potentially fatal electrolyte imbalance caused by severe hydrofluoric acid burns combined with inhalation injury: A case report

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World Journal of Clinical Cases 2019年第20期7卷 3341-3346页

作者： he Fang Guang-Yi Wang xun Wang Fang he jian-Dong Su Department of Burn Surgery Changhai Hospital Affiliated to the Naval Medical UniversityShanghai 200433China Department of Burn and Plastic Surgery Suzhou Hospital Affiliated to Nanjing Medical UniversitySuzhou 215002Jiangsu ProvinceChina

BACKGROUND Hydrofluoric acid(HF)is one of the most common causes of chemical *** burns can cause wounds that deepen and progress *** a result,HF burns are often severe even if they involve a small area of the *** cases of HF burns have mostly reported small HF burn *** cases of HF inhalation injury have been reported to *** SUMMARY A 24-year-old man suffered from extensive hydrofluoric acid burns covering 60%of the total body surface area(TBSA),including deep second degree burns on 47%and third degree burns on 13%of the TBSA,after he fell into a pickling pool containing 15%*** treatments were carried out after the patient was *** fibrillation occurred 9 times within the first 2 h,and the lowest serum Ca2+concentration was 0.192 mmol/L.A dose of calcium gluconate(37 g)was intravenously supplied during the first 24 h,and the total amount of calcium gluconate supplementation was 343 *** membrane oxygenation(ECMO)was applied for 8 d to handle the acute respiratory distress syndrome(ARDS)induced by the HF inhalation *** patient was discharged after 99 d of comprehensive treatment,including skin *** Extensive HF burns combined with an inhalation injury led to a potentially fatal electrolyte imbalance and *** and timely calcium supplementation and ECMO application were the keys to successful treatment of the patient.

关键词： Hydrofluoric acid burn Inhalation injury Hypocalcemia Acute respiratory distress syndrome Extracorporeal membrane oxygenation Case report

Boosting alkaline hydrogen evolution via spontaneous built-in electric field

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Rare Metals 2024年第11期43卷 5848-5859页

作者： Ze-Peng Lv Da-he Zhang Meng-Lu Zang Shao-Long Li Ji-Lin he jian-xun Song Zhongyuan Critical Metals Laboratory Zhengzhou UniversityZhengzhou 450001China henan Province Industrial Technology Research Institute of Resources and Materials Zhengzhou UniversityZhengzhou 450001China College of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

The electrochemical reaction rate strongly depends on the pH of the solution and the relatively sluggish alkaline hydrogen evolution reaction(heR)process,attributed to alterations in the type of proton donor and binding energy,has consistently presented a significant ***,we report a new method for boosting alkaline heR via spontaneous built-in electric field strategy employed on cobalt phosphide nanofibers(NFs)*** anion-cation dual-introduction of V and N on the NFs not only increases the electrochemical surface area but also enhances the catalytic activity,thereby elevating the performance of alkaline *** investigation strategy combining experiments and calculations revealed the charge transfer law between multiple active components and the enhanced regulation mechanism of alkaline heR process,ultimately achieving a nearly twice increase in reaction overpotential of the as-fabricated catalyst at-10 mA·cm^(-2).This new approach provides a potential strategy for improving the efficiency of core catalyst for energy conversion technologies.

关键词： Multiple active sites Built-in electric felid Chemical substitution Hydrogen Electrocatalyst

三氯乙烯药疹样皮炎代谢酶基因多态性的病例对照研究

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中国职业医学 2002年第3期29卷 4-8页

作者：李来玉冷曙光郑玉新何家禧黄建勋何凤生广东省职业病防治院广东广州510300 中国预防医学科学院劳动卫生与职业病研究所 100050 深圳市卫生防疫站 518020

目的　筛选三氯乙烯药疹样皮炎的易感基因。方法　比较 43例病人和 47例健康三氯乙烯接触工人细胞色素P45 0酶 (CYP1A1)、谷胱甘肽S 转移酶 (GSTM1、GSTP1、GSTT1)和N 乙酰基转移酶 (NAT2 )的基因多态性分布 ,并计算相对危险度。结果　N... 详细信息

目的　筛选三氯乙烯药疹样皮炎的易感基因。方法　比较 43例病人和 47例健康三氯乙烯接触工人细胞色素P45 0酶 (CYP1A1)、谷胱甘肽S 转移酶 (GSTM1、GSTP1、GSTT1)和N 乙酰基转移酶 (NAT2 )的基因多态性分布 ,并计算相对危险度。结果　NAT2基因Kpn1位点的变异可显著增加三氯乙烯皮炎的危险性 ;具有NAT2慢代谢基因型的个体患皮炎危险性显著高于快代谢基因型个体。未发现其它代谢酶基因多态性与三氯乙烯皮炎易感性的相关关系。

关键词：三氯乙烯药疹样皮炎基因多态性遗传易感性病例对照研究职业危害