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Chinese j.urnal of Electrical Engineering 2024年第1期10卷 1-2页

作者： li j. Mei H. li S. Tianj.n University China Tsinghua Shenzhen International Graduate School China Lanzhou j.aotong University China

The rapid development of clean and renewable energy technologies represented by wind and solar energy,as well as the continuous growth of load demand,have put forward higher requirements for the safe operation of the power *** performance of power equipment based on traditional dielectric materials is often limited by various defects generated during molding,transportation,assembly,and operation,which cannot meet the reliability requirements of power systems in the new *** detection is an essential technical method in industrial development,which can detect and evaluate the defect and damage status of in-service equipment,key components,and materials without damaging the obj.ct.

关键词： service Application operation

Hypercoagulable state and risk of venous thromboembolism in Cushing syndrome

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Zhong nan da xue xue bao. Yi xue ban = j.urnal of Central South University. Medical sciences 2024年第6期49卷 825-831页

作者： liu Y. Tang Y. Tan H. li j. Department of Endocrinology and Metabolism Center of Pituitary Adenoma and Related Diseases West China Hospital Sichuan University Chengdu 610041 China

库欣综合征(Cushing syndrome，CS)是以高皮质醇血症为特征的内分泌代谢疾病，高皮质醇血症可诱发高凝状态，导致静脉血栓栓塞(venous thromboembolism，VTE)风险增加。无论是垂体来源的库欣病(Cushing disease，CD)，还是肾上腺来源的... 详细信息

库欣综合征(Cushing syndrome，CS)是以高皮质醇血症为特征的内分泌代谢疾病，高皮质醇血症可诱发高凝状态，导致静脉血栓栓塞(venous thromboembolism，VTE)风险增加。无论是垂体来源的库欣病(Cushing disease，CD)，还是肾上腺来源的非促肾上腺皮质激素(adrenocorticotropic hormone，ACTH)依赖性CS，手术均是一线治疗选择。在手术和疾病本身的双重影响下，VTE风险进一步增加，甚至导致肺栓塞，严重威胁患者生命安全。此外，高凝状态的CS患者的心血管病和VTE发生率乃至病死率均高于正常人群，未经治疗的活动性CS患者的VTE发生率较普通人群升高了17.8倍。近年来，CS高凝状态与VTE之间的关系引起了越来越多临床医师的重视。进一步了解CS高凝状态的临床流行病学特点、病理生理机制和VTE及肺栓塞的临床防治，可以为CS患者预防性抗凝药物规范化使用提供参考。.; Cushing syndrome (CS) is an endocrine-metabolic disorder characterized by hypercortisolism. Elevated cortisol levels can induce a hypercoagulable state, increasing the risk of venous thromboembolism (VTE). Both pituitary-origin Cushing disease (CD) and adrenal-origin non-adrenocorticotropic hormone (ACTH)-dependent CS are primarily treated with surgery. The dual impact of surgery and the underlying disease further elevates the risk of VTE, potentially leading to pulmonary embolism, which poses a severe threat to patient survival. Additionally, CS patients in a hypercoagulable state have a higher incidence of cardiovascular diseases and VTE, and even mortality compared with the general population. Untreated active CS patients have a 17.8-fold increased risk of VTE compared to the general population. In recent years, the relationship between the hypercoagulable state in CS and VTE has garnered increasing attention from clinicians. A better understanding of the clinical epidemiological characteristics, pathophysiological mechanisms, and clinical prevention and treatment of VTE and pulmonary embolism in CS can provide valuable references for the standardized use of prophylactic anticoagulant therapy in CS patients.

关键词： Cushing syndrome hypercoagulable state venous thromboembolism

Macrocyclic trichothecenes from Myrothecium verrucaria PA 57 and their cytotoxic activity

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Chinese j.urnal of Natural Medicines 2024年第9期22卷 854-863页

作者： MO j. TAN Y. AI W. li Y. YUAN Y. j.ANG Y. XU K. TAN G. WANG W. li j. liU S. Department of Pharmacy National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha 410008 China Xiangya School of Pharmaceutical Sciences Central South University Changsha 410008 China

Four novel macrocyclic trichothecenes, termed mytoxins D−G (1−4), along with four known analogs (5−8), were isolated from the ethyl acetate extract of fermented rice inoculated with the fungus Myrothecium verrucaria PA57. Each compound features a tricyclic 12,13-epoxytrichothec-9-ene (EPT) core. Notably, mytoxin G (4) represents the first instance of a macrocyclic trichothecene incorporating a glucosyl unit within the trichothecene structure. The structures of the newly identified compounds were elucidated through comprehensive spectroscopic analysis combined with quantum chemical calculations. All isolated compounds demonstrated cytotoxic activity against the CAL27 and HCT116 cell lines, which are models for human oral squamous cell carcinoma and colorectal cancer, respectively. Specifically, mytoxin D (1) and mytoxin F (3) exhibited pronounced cytotoxic effects against both cancer cell lines, with IC50 values ranging from 3 to 6 nmol·L−1. Moreover, compounds 1 and 3 were found to induce apoptosis in HCT116 cells by activating caspase-3. © 2024 China Pharmaceutical University

关键词： Cytotoxicity Macrocyclic trichothecenes Myrothecium verrucaria Secondary metabolite Soil fungi

Role of bisphosphonates in osteoporosis caused by adult growth hormone deficiency

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Zhong nan da xue xue bao. Yi xue ban = j.urnal of Central South University. Medical sciences 2024年第6期49卷 839-847页

作者： Cheng Z. li j. Chen Z. Ren W. Department of Endocrinology Chongqing Traditional Chinese Medicine Hospital 400011 Chongqing China Department of Endocrinology First Affiliated Hospital of Chongqing Medical University 400016 Chongqing China

近年来，生长激素和胰岛素样生长因子已成为骨代谢和重塑的关键调节剂，对于生命各阶段健康骨量的维持均至关重要。研究表明，成人生长激素缺乏会引发骨重塑变化，显著改变骨微结构并增加骨折风险。虽然重组人生长激素替代疗法可以减轻... 详细信息

近年来，生长激素和胰岛素样生长因子已成为骨代谢和重塑的关键调节剂，对于生命各阶段健康骨量的维持均至关重要。研究表明，成人生长激素缺乏会引发骨重塑变化，显著改变骨微结构并增加骨折风险。虽然重组人生长激素替代疗法可以减轻这些负面影响，提高骨密度并降低骨折风险，但其治疗骨质疏松症的效果，特别是对于已有生长激素缺乏症的成年人，似乎有限。双膦酸盐通过抑制破骨细胞中的法尼醇焦磷酸合酶起抗骨吸收的作用，临床试验已证实其可有效改善骨质疏松。因此，对患有骨质疏松的成人生长激素缺乏症患者，建议在使用生长激素替代疗法的同时使用双膦酸盐。.; In recent years, growth hormone and insulin-like growth factors have become key regulators of bone metabolism and remodeling, crucial for maintaining healthy bone mass throughout life. Studies have shown that adult growth hormone deficiency leads to alterations in bone remodeling, significantly affecting bone microarchitecture and increasing fracture risk. Although recombinant human growth hormone replacement therapy can mitigate these adverse effects, improving bone density, and reduce fracture risk, its effectiveness in treating osteoporosis, especially in adults with established growth hormone deficiency, seems limited. Bisphosphonates inhibit bone resorption by targeting farnesyl pyrophosphate synthase in osteoclasts, and clinical trials have confirmed their efficacy in improving osteoporosis. Therefore, for adult growth hormone deficiency patients with osteoporosis, the use of bisphosphonates alongside growth hormone replacement therapy is recommended.

关键词： adult growth hormone deficiency bisphosphonates growth hormone insulin-like growth factor 1 osteoporosis skeleton

Surface Characterisation of Silicon Based MEMS

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Chemical Research in Chinese Universities 2004年第4期20卷 407-410页

作者： li j. CUI Z M. A. Baker The Surface Analysis Laboratory School of Engineering University of SurreyRutherford Appleton LaboratoryThe Surface Analysis Laboratory School of Engineering University of Surrey Guildford GU2 7XH UKChilton Didcot UKGuildford GU2 7XH UK

Polysilicon Microelectromechanical systems(MEMS) are the subj.ct of intensive researches. Surface chemistry and topography of a MEMS test structure fabricated at Sandia National Laboratory, USA, were studied by means of scanning electron microscopy(SEM), X-ray photoelectron spectroscopy(XPS) and atomic force microscopy(AFM). XPS C_ 1sand Si_ 2pspectra from the polysilicon components, silicon nitride substrate and a reference silicon wafer were compared. The results confirm the presence of a self-assembled monolayer(SAM) on the MEMS surface. An island-like morphology was found on both polysilicon and silicon nitride surfaces of the MEMS. The islands take the form of caps, being up to 0.5 μm in diameter and 20 nm in height. It is concluded that the co-existence of columnar growth and equiaxed growth during the low pressure chemical vapor deposition(LPCVD) of these layers leads to the observed morphology and the islands are caps to the columnar structures.

关键词： Microelectromechanical systems XPS Atomic force microscopy

EFFECTS OF TREATMENT TIME ON CORROSION OF DIFFUSION-ALLOYED COATINGS OF PURE MAGNESIUM

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Acta Metallurgica Sinica(English Letters) 2007年第1期20卷 72-78页

作者： Y.P. Ma j. li j. Zhu L. Yang Y.G. liu Z.Y. li F. Zhao School of Metallurgic Engineering Xi＇an University of Architecture ＆ Technology Xi＇an 710055 China

The corrosion resistance of pure magnesium with surface alloying layer obtained by a solid diffusion alloying technique has been analyzed. To establish the optimum treatment time, the experiments were performed at 480℃ for different solid diffusion time （8, 16, and 24h）. The diffusion interaction effectiveness between Zn, Al mix powder and the sample surface, depending on the treatment time for diffusion at given temperatures, has an obvious influence on corrosion resistance and corrosion mechanism. Corrosion properties were studied using the constant immersion test （in 3.0% NaCl solution, temperature is （28±1）℃, and time is 96h）. Optical microscopy （OM） and EDS （energy dispersive spectrum） composition analysis were used to examine the cross-sectional microstructural characteristics of alloyed layer of treated samples. It is shown that in comparison with the untreated samples, the treated ones possess a better corrosion resistance. The Al5Mg11Zn4 phase, which formed as a continuous phase due to the diffusion of Al, Zn, and Mg elements and subsequent interaction on the outermost layer of diffusion alloying zones （especially the samples treated for 24h at 480℃）, was inert to the chloride solution compared with pure magnesium and acted as a corrosion barrier, and therefore the best corrosion resistance was obtained. This protective action of Al5Mg11Zn4 phase was found to change with its amount, which was controlled by the diffusion time at given temperature. It was concluded that the continuous Al5Mg11Zn4 phase （WP-zone） of the reacted layer in pure magnesium was beneficial from the point of view of corrosion resistance.

关键词： pure magnesium solid diffusion treatment time microstructure corrosion

PROPERTIES OF THREE-DIMENSIONAL MOVEMENT OF SANDY WATER DISCHARGED INTO A LAKE

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j.urnal of Hydrodynamics 2001年第2期13卷 72-76页

作者： Deng, Y. li, j. li, K.F. Zhao, W.Q. State Key Lab. of High Speed Flow Sichuan Univ. Chengdu 610065 China

A Random Traj.ctory Model (RTM) for solid-liquid two-phase flow based on the Lagrangian Method is presented in this paper. The effects of water drag force, pressure gradient force, buoyancy and virtual mass force on the particles were included and the turbulent dispersion was modeled by random method. Three-dimensional k-Ε model was used to calculate the flow field. A pumped-storage power station, with a natural lake as its upper pool, was taken as a case for the study. Averaged movement traj.ctories, velocities and the volume-concentration distributions for 5 groups of sediment particles, were predicted with RTM. The possible silted locations in the lake were also predicted.

关键词： Boundary conditions Computer simulation Lakes Sand Three dimensional Two phase flow Velocity

Synthesis and Catalyzing Behavior of Olefin Polymerization of cis-Cyclopentene Bridged Titanocenes

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Chinese Chemical Letters 2000年第11期11卷 979-980页

作者： li j.S. Xiong C.H. Ma Y.Q. li j. Chen X. Inst. of Elemento-Organic Chemistry Nankai University Tianjin 300071 China Department of Chemistry Tianjin Normal University Tianjin 300070 China

Two cis-cyclopentene bridged titanocenes have been synthesized. Two homogeneous Ziegler catalysts prepared by activation of synthesized compounds with methylalumoxane are active for ethylene polymerization reactions.

关键词： cis Ti Synthesis and Catalyzing Behavior of Olefin Polymerization of cis-Cyclopentene Bridged Titanocenes

Ubiquitin-Specific Protease 14 （UBP14） Is Involved in Root Responses to Phosphate Deficiency in Arabidopsis

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Molecular Plant 2010年第1期3卷 212-223页

作者： Wen-Feng li Paula j. Perry Nulu N. Prafulla Wolfgang Schmidt Institute of Plant and Microbial Biology Academia Sinica 115 Taipei

A mutant isolated from a screen of EMS-mutagenized Arabidopsis lines, per1, showed normal root hair development under control conditions but displayed an inhibited root hair elongation phenotype upon Pi deficiency. Additionally, the per1 mutant exhibited a pleiotropic phenotype under control conditions, resembling Pi-deficient plants in several aspects. Inhibition of root hair elongation upon growth on low Pi media was reverted by treatment with the Pi analog phosphite, suggesting that the mutant phenotype is not caused by a lack of Pi. Reciprocal grafting experiments revealed that the mutant rootstock is sufficient to cause the phenotype. Complementation analyses showed that the PER1 gene encodes an ubiquitin-specific protease, UBP14. The mutation caused a synonymous substitution in the 12th exon of this gene, resulting in a lower abundance of the UBP14 protein, probably as a consequence of reduced translation efficiency. Transcriptional profiling of per1 and wild-type plants subj.cted to short-term Pi starvation revealed genes that may be important for the signaling of Pi deficiency. We conclude that UBP14 function is crucial for adapting root development to the prevailing local availability of phosphate.

关键词： Phosphate deficiency root hairs ubiquitin-specific protease root development.

Ischemic and hypoxic preconditioning protect cardiac muscles via intracellular ROS signaling

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Frontiers in Biology 2013年第3期8卷 305-311页

作者： li ZUO William j. ROBERTS Rosa C. TOLOMELLO Adam T. GOINS Molecular Physiology and Biophysics Laboratory Department of Biological Sciences Oakland University Rochester MI 48326 USA

Oxidative stress can cause extensive damage to cardiac tissue under reperfusion conditions. However, preconditioning the myocardium may diminish these negative effects and alleviate reperfusion inj.ry. There are a variety of preconditioning therapies, such as ischemic preconditioning （IPC） and hypoxie preconditioning （HPC）, each targeting specific channels, receptors, and/or intracellular molecules. Ischemic preconditioning involves brief periods of ischemia followed by brief periods of reperfusion, thus strengthening the cardiac resistance for a longer period of ischemia. IPC involves complex mechanisms, some of which are still not completely understood today. Nevertheless, many studies have already established models of IPC. In addition, similar to IPC, HPC has also been recognized as preventing reperfusion inj.ry. Reactive oxygen species （ROS） are known mediators of IPC and HPC. Particularly, mitochondria-generated ROS initiate activity of several beneficial preconditioning pathways. The role of ROS is paradoxical; low levels of ROS are key factors in signaling IPC/HPC, but high levels of ROS can contribute to increased oxidative stress on cardiomyocytes. Therefore, it is important to determine the molecular mechanism of IPC and HPC to avoid excessive accumulation of ROS to prevent cardiac inj.ry. In this review, we will outline IPC and HPC, explaining the putative role of ROS in both pathways. We will also discuss preconditioning efficacy in certain conditions such as exercise and how the aging myocardium responds to preconditioning therapies.

关键词： hypoxia ischemia-reperfusion ROS cardiomyocyte preconditioning