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Kinematics analysis of a novel all-attitude flight simulator

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Science China(Information Sciences) 2010年第2期53卷 236-247页

作者： WANG XiaoChen , zhao hui, ma Kemao, HUO Xin & YAO Yu Control and Simulation Center, Harbin Institute of Technology, Harbin 150080, China Control and Simulation Center Harbin Institute of Technology Harbin China

To overcome the kinematic singularity limitation of simulator, which is unavoidable in a three-axis architecture, an all-attitude flight simulator in a four-axis architecture is proposed. The simulator can always provide 3DOF motion by applying redundant manipulator mechanism. For direct kinematics of the manipulator, a dual-Euler method is adopted to solve the expressions of attitude angles; thus computation singularity of all- attitude angles is overcome. For inverse kinematics of the manipulator, pseudo-inverse gradient projection method is used to obtain optimal velocity solution. Then, based on dynamic control method, optimal position solution is obtained. The proposed inverse kinematics algorithm can achieve desired attitudes, as well as can avoid kinematics singularity and axis angle limits. The simulation results show that the kinematic performance of the four-axis all-attitude flight simulator is superior to that of a three-axis simulator.

关键词： all-attitude flight simulator kinematic singularity direct kinematics inverse kinematics

转速对湿式离合器局部润滑及摩擦特性影响研究

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兵工学报 2017年第4期38卷 625-633页

作者：赵二辉马彪李和言杜秋李慧珠马成男北京理工大学机械与车辆学院北京100081 北京电动车辆协同创新中心北京100081

针对湿式离合器局部润滑及摩擦特性的影响因素,建立了摩擦副微观混合润滑模型。考虑了微凸峰接触和局部温升的影响,分析了转速对湿式离合器摩擦副局部压强分布、油膜和微凸峰承压比、实际接触面积、局部温升的影响。同时,利用摩擦磨损... 详细信息

针对湿式离合器局部润滑及摩擦特性的影响因素,建立了摩擦副微观混合润滑模型。考虑了微凸峰接触和局部温升的影响,分析了转速对湿式离合器摩擦副局部压强分布、油膜和微凸峰承压比、实际接触面积、局部温升的影响。同时,利用摩擦磨损试验机进行小试样柱销-摩擦盘试验,分析了不同转速下离合器摩擦系数变化规律。结果表明:随着速度的增加,润滑油膜动压作用显著增强,摩擦副实际接触面积明显减小,法向载荷最终主要由润滑油膜承担;摩擦系数主要受微凸峰实际接触面积变化的影响,变化规律与微凸峰实际接触面积呈大致对应关系。

关键词：兵器科学与技术湿式离合器混合润滑摩擦特性转速影响

Correlation between 1,5-anhydroglucitol and glycemic excursions in type 2 diabetic patients

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Chinese Medical Journal 2011年第22期124卷 3641-3645页

作者： SUN Jie DOU Jing-tao WANG Xian-ling YANG Guo-qing LU zhao-hui ZHENG Hua ma Fang-ling LU Ju-ming MU Yi-ming Department of Endocrinology Chinese People＇s Liberation Army General Hospital Beijing 100853 China

Background The accurate and comprehensive assessment of glycemic control in patients with diabetes is important for optimizing glycemic management and for formulating personalized diabetic treatment schemes. This study aimed to analyze the correlation between 1,5-anhydroglucitol （1,5-AG） and glycemic excursions in type 2 diabetic patients. Methods Seventy-one outpatients with type 2 diabetes mellitus were randomly recruited from Chinese People＇s Liberation Army General Hospital. Using a continuous glucose monitoring system （CGMS）, these patients＇ blood glucose levels were monitored for three consecutive days to obtain mean blood glucose （MBG） data. Intraday glycemic excursions were evaluated using the mean amplitude of glycemic excursions （maGE）, the largest amplitude of glycemic excursions （LAGE）, standard deviation of blood glucose （SDBG） and the M-value. Interday glycemic excursion was assessed by absolute mean of daily difference （MODD）. Postprandial glycemic fluctuations were evaluated using postprandial glucose excursions （PPGE） and postprandial incremental area under the curve （iAUC）. Fasting venous blood samples were collected to measure serum 1,5-AG, whole-blood hemoglobin Alc （HbAlc） and serum glycated albumin （GA）. Clinical markers of glycemia and parameters of glycemic excursions from CGMS were analyzed using the Pearson correlation coefficient and multivariate stepwise regression. Results Pearson correlation analysis revealed that 1,5-AG was significantly correlated with maGE, SDBG, M-value, LAGE, PPGE and iAUC （r values were-0.509,-0.430,-0.530,-0.462,-0.416 and-0.435, respectively, P 〈0.01）, especially in moderately and well-controlled patients, based on defined HbAlc levels. Multivariate stepwise regression analysis revealed a negative correlation between 1,5-AG and the above parameters, but not HbAlc and GA. Finally, HbAlc and GA were positively correlated with MBG and fasting blood glucose （FBG）. Conclusions 1,5-AG was much better than HbAlc and GA

关键词： 1,5-anhydroglucitol type 2 diabetes mellitus glycemic excursions

Deficits in LTP facilitation by 5-HT2A receptor antagonist in a mouse model for fragile X syndrome

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Deficits in LTP facilitation by 5-HT2A receptor antagonist i...

Vector meson's spin alignments in high energy reactions

中国药理学会第十一次全国学术会议

作者： XU zhao-hui,ma Lan,zhao Ming-gao (Department of Pharmacology,School of Pharmacy,Fourth Military Medical University,Xi’an 710032,China)

Fragile X syndrome(FXS) is a common inherited mental retardation caused by the lack of fragile X mental retardation protein(FMRP) due to silencing of the Fmr1 ***,we report that FMRP is involved in serotonin(5-HT) modulation of synaptic *** inhibition of 5-HT2A receptor(5-HT2AR) by R-96544 facilitated the induction of long-term potentiation (LTP) in the anterior cingulate cortex(ACC) of the wild-type(WT) *** facilitation of LTP by R-96544 depended on the activation of NMDARs and elevated postsynaptic Ca concentrations,indicating the postsynaptic mechanism underlying the LTP induction. However,the LTP facilitation by R-96544 was reduced in the ACC of the Fmr1 knock-out(KO) ***,AMPA receptor subtype 1(GluR1) surface expression in response to 5-HT2AR inhibition was impaired in the cultured ACC neurons from Fmr1 KO ***,these findings suggest that FMRP is involved in serotonin receptor signaling and contributes to GluR1 surface expression induced by 5-HT2AR inactivation.

关键词： serotonin fragile X syndrome synaptic plasticity anterior cingulate cortex

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-hui Chen Zuo-Tang Liang Yu-Gang ma Xin-Li Sheng Qun Wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation

The efficacy of sertraline and sildenafil in the treatment of premature ejaculation

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Hypidone hydrochloride(YL-0919)ameliorates functional deficits after traumatic brain injury in mice by activating the sigma-1 receptor for antioxidation

第十五届全国泌尿外科学术会议

作者： Hong Kai, Jiang hui, zhao Lianming, ma Lulin, Huang Yi, Yuan Renpei, Chen Qian Urology department, Peking University 3rd Hospital, 100083

Background: Premature ejaculation is a common male sexual dysfunction, affecting 20-30% of sexually active men. Drugs for the treatment of premature ejaculation are still not fully satisfied. However, selective serotonin reuptake inhibitors (SSRIs) are very common used for PE patients. Our purpose is to compare the efficacy of combination of sertraline(SSRI) and sildenafil with sertraline only in PE patients and try to know if this combination treatment could improve orgasm as well as prolong the IELT. Methods: a total of 30 consecutive heterosexual men aged 23-45 years with premature ejaculation were included in this study. The duration with premature ejaculation in the patients ranged from 7 to 61 months. All these patients were efficacy for 50mg sertraline daily for 8 weeks before the combination therapy. After minimum of 4 weeks none therapy for PE, we started to combine 50mg sertraline daily and 100mg sildenafil (60 minutes before intercourse) in the prescription for all these patients. They need to attempt a sexual intercourse with sildenafil at least once a week in this study. Results: Before the combination therapy, the score of IIEF-5 in 7 patients (23.3%) were less than 21 (mean 17.7). After given sertraline plus sildenafil, all of the patients increased IIEF-5 score over 22. Patients have all prolonged their IELT (from mean 72s to 264s), but there were no significant difference between combine therapy and sertraline alone (mean 252s, p>0.05). The orgasm satisfaction of sexual intercourse was mean 4.5 before the combine therapy (sertraline only) and 7.3 after the therapy (t<0.01). No severe side effect has been reported, but there were slight and temporary well tolerated side effects been observed, such as flush, headach, nasal congestive and Dyspepsia. Conclusions: With slight and well tolerated side effect, combination therapy of sertraline and sildenafil for PE patients can not only prolong the IELT, but also increase the orgasm satisfaction of sexual i

关键词： premature ejaculation sertraline sildenafil treatment orgasm

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Neural Regeneration Research 2025年第8期20卷 2325-2336页

作者： Yafan Bai hui ma Yue Zhang Jinfeng Li Xiaojuan Hou Yixin Yang Guyan Wang Yunfeng Li Department of Anesthesiology Beijing Tongren HospitalCapital Medical UniversityBeijingChina Beijing Institute of Basic Medical Sciences BeijingChina Hebei North University ZhangjiakouHebei ProvinceChina Beijing Institute of Pharmacology and Toxicology State Key Laboratory of Toxicology and Medical CountermeasuresBeijing Key Laboratory of NeuropsychopharmacologyBeijingChina

Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary *** this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain *** experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain ***,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 ***,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain ***,YL-0919 effectively combated oxidative stress both in vivo and in *** protective effects of YL-0919 were partially inhibited by *** results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist ***-0919 may have potential as a new treatment for traumatic brain injury.

关键词： antidepressant drug blood-brain barrier cognitive function hypidone hydrochloride(YL-0919) neurological function nuclear factor-erythroid 2 related factor 2 oxidative stress sigma-1 receptor superoxide dismutase traumatic brain injury

Constructing Donor–Acceptor‑Linked COFs Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery

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Nano-Micro Letters 2025年第1期17卷 456-471页

作者： Genfu zhao Hang ma Conghui Zhang Yongxin Yang Shuyuan Yu Haiye Zhu Yongjiang Sun Hong Guo School of materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China Yunnan Yuntianhua Co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United Graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal *** study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COFs)based on intramolecular charge transfer *** other reported COFbased solid-state electrolyte,the developed concept with D–A-linked COFs not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal *** introduced strong electronegativity F-based ligand in COF electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LiFePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor F atoms,which effectively expedites electron transferring from porphyrin to F-based ligand and enhances Li^(+)***,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state Li metal battery

Small extracellular vesicles derived from human induced pluripotent stem cell-differentiated neural progenitor cells mitigate retinal ganglion cell degeneration in a mouse model of optic nerve injury

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Neural Regeneration Research 2025年第2期20卷 587-597页

作者： Tong Li hui-Min Xing Hai-Dong Qian Qiao Gao Sheng-Lan Xu Hua ma Zai-Long Chi State Key Laboratory of Ophthalmology Optometry and Visual ScienceEye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina

Several studies have found that transplantation of neural progenitor cells(NPCs)promotes the survival of injured ***,a poor integration rate and high risk of tumorigenicity after cell transplantation limits their clinical *** extracellular vesicles(sEVs)contain bioactive molecules for neuronal protection and *** studies have shown that stem/progenitor cell-derived sEVs can promote neuronal survival and recovery of neurological function in neurodegenerative eye diseases and other eye *** this study,we intravitreally transplanted sEVs derived from human induced pluripotent stem cells(hiPSCs)and hiPSCs-differentiated NPCs(hiPSC-NPC)in a mouse model of optic nerve *** results show that these intravitreally injected sEVs were ingested by retinal cells,especially those localized in the ganglion cell *** with hiPSC-NPC-derived sEVs mitigated optic nerve crush-induced retinal ganglion cell degeneration,and regulated the retinal microenvironment by inhibiting excessive activation of *** analysis further revealed that hiPSC-NPC derived sEVs transported neuroprotective and anti-inflammatory miRNA cargos to target cells,which had protective effects on RGCs after optic nerve *** findings suggest that sEVs derived from hiPSC-NPC are a promising cell-free therapeutic strategy for optic neuropathy.

关键词： exosome miRNA neural progenitor cell neurodegeneration neuroinflammation neuroprotection optic nerve crush optic neuropathy retinal ganglion cell small extracellular vesicles