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Stream temperature dynamics in Nam Co basin, southern Tibetan Plateau

Journal of Mountain Science 2017年第12期14卷 2458-2470页

作者： GAO Tan-guang KANG Shi-chang zhang ting-jun YANG Da-qing SHANG Jian-guo QIN Xiang College of Earth and Environmental Sciences Lanzhou University State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences National Hydrology Research Centre Environment Canada Saskatoon Saskatchewan

Stream temperatures are sensitive to climate change and runoff regime variations. A comprehensive understanding on the effects of glacial melting on the stream temperatures are important in the Tibetan Plateau, of which contains the largest ice volume outside Polar Regions. This study documented the high-resolution stream temperature thermal regimes from glacier-fed and non-glacial rivers at four sites, versus a high-resolution glacier mass balance monitoring at Zhadang glacier, during summer melt seasons from 2007-2009 in the Nam Co basin of southern Tibetan Plateau. The results showed mean summer stream temperature and magnitude of daily thermal variation were lower at all sites when compared with alpine glacierized environments at lower latitudes. Mean stream temperatures for glacier-fed rivers(4.0℃ to 6.5℃)were minimum and least variable near the glacier terminus with increasing toward downstream(+0.13℃ km^(–1) to +0.28℃ km^(–1)). Meanwhile, stream temperature in 2008 was similar to that in 2007 and2009. For the non-glacial rivers, mean stream temperatures was about 9.0℃ with significantly warmer in summer months in 2009 and 2007 than that in 2008. These differences indicated that stream temperature was strongly influenced by discharge and precipitation. Particularly, the glacier mass balance played a large role on the stream temperature directly when the glacier melt contributed more than 50% of the glacial river runoff. Our results demonstrated the stream thermal variability from southern Tibetan rivers and provided new insight into the influence of glacier mass balance on stream thermal variability in high-altitude river system.

关键词： Stream temperature Thermal regime Glacier mass balance Tibetan Plateau

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Prediction of a common neutralizing epitope of H5N1 avian influenza virus by in silico molecular docking

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Chinese Science Bulletin 2008年第6期53卷 868-877页

作者： YAN YuanQing LI ShaoWei YANG ChunYan LUO WenXin WANG MingQiao CHEN YiXin LUO HaiFeng wu ting zhang jun XIA NingShao National Institute of Diagnostics and Vaccine Development in Infectious Diseases/Key Laboratory of the Ministry of Education forCell Biology and Tumor Cell Engineering Xiamen University Xiamen 361005 China

The H5N1 avian influenza virus (AIV) has widely spread in Asia, Europe and Africa, making a large amount of economic loss. Recently, our research group has screened a common neutralizing mono- clonal antibody named 8H5, which can neutralize almost all H5 subtype AIV ever isolated so far. Obvi- ously, this monoclonal antibody would benefit for research and development of the universal AIV vac- cine and design of the drug against H5N1 AIV in high mutation rate. In this study, the homology mod- eling was applied to generate the 3D structure of 8H5 Fab fragment, and "canonical structure" method was used to define the specified loop conformation of CDR regions. The model was subjected to en- ergy minimization in cvff force field with Discovery module in Insight II program. The resulting model has correct stereochemistry as gauged from the Ramachandran plot calculation and good 3D-structure compatibility as assessed by interaction energy analysis, solvent accessible surface (SAS) analysis, and Profiles-3D approach. Furthermore, the 8H5 Fab model was subjected to docking with three H5 subtype hemagglutinin (HA) structures deposited in PDB (ID No: 1jsm, 2ibx and 2fk0) respectively. The result indicates that the three docked complexes share a common binding interface, but differ in bind- ing angle related with HA structure similarity between viral subtypes. In the light of the three HA inter- faces with structural homology analysis, the common neutralizing epitope on HA recognized by 8H5 consists of 9 incontinuous amino acid residues: Asp68, Asn72, Glu112, Lys113, Ile114, Pro118, Ser120, Tyr137, Tyr252 (numbered as for 1jsm sequence). The primary purpose of the present work is to provide some insight into structure and binding details of a common neutralizing epitope of H5N1 AIV, thereby aiding in the structure-based design of universal AIV vaccines and anti-virus therapeutic drugs.

关键词：禽流感 H5N1病毒抗原决定基红血球凝聚素

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Optimal microsurgical treatment of dorsum sellae meningioma

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Chinese Medical Journal 2009年第16期122卷 1857-1861页

作者： GENG Su-min zhang jun-ting zhang Li-wei WU Zhen WANG Zhong-cheng Department of Neurosurgery Beijng Tiantan Hospital Capital Medical University Beijing 100050 China

Background There are few reports of microsurgical treatment of dorsum sellae meningiomas--which, because of location, size, and differences in growth direction, clinical presentations, degree of surgical difficulty, have varied posttreatment sequelae. In pursuit of an optimal microsurgical treatment option for dorsum sellae meningioma patients, we performed a retrospective analysis of eight microsurgery-treated patients in our set up. Methods Clinical data of eight microsurgery-treated dorsum sellae meningioma patients were analyzed. Dorsum sellae meningiomas were classified into 2 types based on tumor location, size, and direction of growth. Type Ⅰ tumors （dorsum sellae-inferior third ventricle type, four cases） were resected by craniotomy via the frontotemporal or orbitozygomatic approach. Type Ⅱ tumors （dorsum sellae-third ventricle type, 4 cases） were resected by frontal craniotomy via the transcallosal-interforniceal approach. Results Complete tumor resection was achieved in all the eight patients. In Type Ⅰ tumor patients, the only postoperative complication was oculomotor nerve palsy. In Type Ⅱ tumor patients, the postoperative complications included hyperthermia, electrolyte imbalances, endocrinologic disturbances, and hydrocephalus. The mean follow-up was 2.1 years. Four patients returned to normal life and found a job, two were able to live independently, one required assistance, while one died. Conclusions Dorsum sellae meningioma surgery is challenging, and resection of Type Ⅱ tumors is more difficult than Type Ⅰ tumors. The selection of a suitable microsurgical approach based on tumor type, and the active treatment of postoperative complications are important means of increasing therapeutic efficacy.

关键词： dorsum sellae meningioma microsurgery

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Management of intracranial invasive olfactory neuroblastoma

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Chinese Medical Journal 2007年第3期120卷 224-227页

作者： zhang Li-wei zhang Ming-shan QI Ji zhang jun-ting LI Gui-lin LUO Lin WANG Zhong-cheng Department of Neurosurgery Beijing Tiantan Hospital CapitalMedical University Beijing 100050 China Beijing Institute of Neurosurgery Capital Medical UniversityBeijing 100050 China

Background Olfactory neuroblastoma （ONB） is a rare tumor that often arise from the nasal cavity. The aim of this study was to investigate the clinical characteristics and treatments of intracranial invasive ONB. Methods Between July 2001 and August 2005, 5 patients with intracranial invasive ONB were treated in our department. Their clinical features, radiological and pathological characteristics, and surgical treatments were analyzed. Among the 5 patients, 1 received transnasal biopsy, and 4 were operated through the transfrontal or extended bifrontal approaches to reconstruct the skull base. After the operation, all the patients received radiotherapy, and one received chemotherapy. They were followed up for 6 to 45 months. Results The ONB was resected totally in the 4 patients. In all the patients, nasal obstruction was alleviated without cerebrospinal fluid leakage. The visual acuity was improved in 3 patients, who had a decreased visual acuity before the operation. Two patients had metastasis into the lumbosacral spinal canal 6 and 8 months after the operation, one of them received a second operation and the other died. Conclusion ONB has no specific symptoms. Intracranial ONB should be resected as far as possible, and treated by radiotherapy after the operation.

关键词： esthesioneuroblastoma, olfactory therapy

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Intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation for preservation of facial nerve function in patients with large acoustic neuroma

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Chinese Medical Journal 2007年第4期120卷 323-325页

作者： LIU Bai-yun TIAN Yong-ji LIU Wen LIU Shu-ling QIAO Hui zhang jun-ting Jim Gui-jun Department of Neurosurgery Beijing Tiantan Hospital CapitalMedical University Beijing 100050 China Beijing Neurosurgical Institute Beijing 100050 China

Background Although various monitoring techniques have been used routinely in the treatment of the lesions in the skull base, iatrogenic facial paresis or paralysis remains a significant clinical problem. The aim of this study was to investigate the effect of intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation on preservation of facial nerve function. Method From January to November 2005, 19 patients with large acoustic neuroma were treated using intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation （TCEMEP） for preservation of facial nerve function. The relationship between the decrease of MEP amplitude after tumor removal and the postoperative function of the facial nerve was analyzed. Results MEP amplitude decreased more than 75% in 11 patients, of which 6 presented significant facial paralysis （H-B grade 3）, and 5 had mild facial paralysis （H-B grade 2）. In the other 8 patients, whose MEP amplitude decreased less than 75%, 1 experienced significant facial paralysis, 5 had mild facial paralysis, and 2 were normal. Conclusions Intraoperative TCEMEP can be used to predict postoperative function of the facial nerve. The decreased MEP amplitude above 75 % is an alarm point for possible severe facial paralysis.

关键词： acoustic neuroma motor evoked potentials cranial nerves

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Compare two methods of measuring DNA damage induced by photogenotoxicity of fluoroquinolones

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Acta Pharmacologica Sinica 2004年第2期25卷 45-49页

作者： ting zhang, jun-ling LI, Jian XIN, Xiao-chao MA, Zeng-hong TU1 State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai 201203, China 中科院上海生命科学院 State Key Laboratory of Drug Research CAS 上海 201203

AIM: To compare two methods of measuring DNA damage induced by photogenotoxicity of fluoroquinolones (FQ). METHODS: Lomefloxacin (LFLX), sparfloxacin (SPFX), ciprofloxacin (CPFX), and levofloxacin (LELX) were tested by comet assay and photodynamic DNA strand breaking activity under the different conditions of UVA irradiation. RESULTS: In comet assay, photogenotoxicity was evident at SPFX 1 mg/L, LFLX 5 mg/L, and CPFX 5 mg/L, and LELX 10 mg/L. In photodynamic DNA srand-breaking activity, SPFX and LFLX induced the conver- sion of the supercoiled form into the nicked relaxed form at 10-50 μmol/L, while CPFX at 25 μmol/L and LELX at 50 μmol/L. CONCLUSION: There were good correlations between the two methods to detect DNA damage induced by phototoxicity of fluoroquinolones. Photodynamic DNA strand breaking activity was a good method to detect DNA damage induced by photogenotoxicity of fluoroquinolones as well as comet assay.

关键词： fluoroquinolones phototoxic dermatitis comet assay

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基于钙钛矿的二维铁磁体Sr_(2)RuO_(4)单层

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物理学报 2024年第22期73卷 205-212页

作者：张俊廷纪克谢禹李超中国矿业大学材料与物理学院徐州221116

目前对二维铁磁体的研究主要集中在范德瓦尔斯材料领域,而无应力束缚的自支撑二维钙钛矿薄膜的成功制备为设计范德瓦耳斯材料之外的二维铁磁体提供了良好的契机.钙钛矿氧化物SrRuO_(3)作为典型的钙钛矿巡游铁磁体,在诸多领域具有广阔应... 详细信息

目前对二维铁磁体的研究主要集中在范德瓦尔斯材料领域,而无应力束缚的自支撑二维钙钛矿薄膜的成功制备为设计范德瓦耳斯材料之外的二维铁磁体提供了良好的契机.钙钛矿氧化物SrRuO_(3)作为典型的钙钛矿巡游铁磁体,在诸多领域具有广阔应用前景.本文结合第一性原理计算、对称性分析和蒙特卡罗模拟方法研究了其钙钛矿单层(化学式Sr_(2)RuO_(4))的晶格动力学、基态结构、电子与磁性质以及电场调控效应,并揭示了哈伯德参量U的影响.证实单层基态结构为八面体旋转畸变产生的结构相(空间群P4/mbm),具有铁磁半金属性质和面外易磁化轴.铁磁性主要源于最近邻自旋之间的强铁磁交换作用.利用自洽测定U值模拟出的居里温度为177 K,与其块体相的值比较接近.外加电场可以显著调制其电子和磁性质,甚至诱导铁磁半金属相到铁磁金属相的转变.本文为开发基于钙钛矿的二维铁磁体及利用电场调控二维磁性提供了借鉴.

关键词：二维铁磁性钙钛矿第一性原理

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基于Simulink参数变化对油气悬挂输出特性影响分析

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机械设计与制造 2023年第8期 200-202,207页

作者：张俊停张昊河南交通职业技术学院汽车学院河南郑州450000 东南大学仪器科学与工程学院江苏南京210000

根据结构特点和工作原理,获取不同工况的输出力;在此基础上对非线性刚度和阻尼特性进行分析,并分别获取理论模型;根据理论模型和实际1/4车辆油气悬挂特点,基于Simulink建立数学仿真模型,分析悬挂缸的主要结构参数和工作参数变化对其输... 详细信息

根据结构特点和工作原理,获取不同工况的输出力;在此基础上对非线性刚度和阻尼特性进行分析,并分别获取理论模型;根据理论模型和实际1/4车辆油气悬挂特点,基于Simulink建立数学仿真模型,分析悬挂缸的主要结构参数和工作参数变化对其输出特性,尤其是刚度特性和阻尼特性所产生的影响进行分析。利用油气悬挂液压试验台,对仿真分析的输出特性进行验证分析,获取关键参数进行对比,以验证数学模型和结果的可靠性。结果可知:对油气悬挂刚度特性影响最大的因素为缸筒、活塞杆等的直径,二者的影响趋势相反,前者呈现负相关,而后者则呈现正相关;悬挂中气体的高度与刚度特性呈现负相关;簧上质量的影响与前述直径尺寸的影响趋势基本一致,发生改变时,也是曲线的位置高低产生重要影响,但是影响略低于直径变化的影响,其值不断增加时,刚度特性的变化则逐渐减小;阻尼特性的变化在拉伸压缩阶段并非对称的,而是纯在较大的不对称性;相对速度值相同,而方向相反时,拉伸行程的阻尼力是压缩行程的3倍左右,这与设计目标是一致的;试验测试结果与仿真分析结果比较吻合,误差较小,控制在5%以内;因此,所建立的模型是准确的,获得的分析结果是可靠的,能够准确描述油气悬挂的特性,为此类研究提供参考。

关键词：油气悬挂阻尼刚度输出特性模型试验

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