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Antibacterial activity of na.ingenin-rich fraction of pigeon pea leaves toward Salmonella thypi

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a.ian Pa.ific Journal of Tropical Biomedicine 2017年第8期7卷 725-728页

作者： Sa.ifa Agus Suminar Setia.i Achma.i nisa.Rachma.ia Muba.ik Department of Chemistry Faculty of Mathematics and Natural SciencesBogor Agricultural University Department of Biology Faculty of Mathematics and Natural SciencesBogor Agricultural University

To identify bioactive compound in pigeon pea leaves (Cajanus cajan) that inhibits Salmonella thypi (S. thypi).MethodsThe leaf sample was powdered and macerated with methanol and fractioned by liquid-liquid extraction using ethyl acetate. The fraction was chromatographed and the isolates were identified for major component with liquid chromatography-mass spectrometry and the antibacterial activity was tested against S. thypi by Kirby-Bauer *** 1 from the ethyl acetate fraction formed a yellowish solid with m/z 272, identified as na.ingenin. The na.ingenin-rich fraction shows fairly well inhibitory toward S. thypi in compa.ison with *** shows antibacterial activity and can be developed to treat typhoid.

关键词： Antibacterial activity Cajanus cajan Flavanones Na.ingenin Salmonella thypi Typhoid

Compa.ison of the effects of intra.itreal beva.izumab and dexamethasone in experimental posterior penetra.ing eye injury

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interna.ional Journal of Ophthalmology(English edition) 2018年第4期11卷 575-579页

作者： Ayse Oner nisa.Kahraman Saim Ozdamar Esra Balcioglu Department of Ophthalmology Faculty of Medicine Erciyes University Department of Histology and Embryology Faculty of Medicine Erciyes University

AiM： To compare the effects of intra.itreal anti-vascular endothelial growth factor（VEGF） and dexamethasone in an experimental rabbit model of posterior penetra.ing ocular ***： Thirty white New Zealand rabbits were included in the study. A posterior penetra.ing ocular injury was performed at the superotemporal quadrant. They were randomly divided into three groups. The rabbits in group 1 received intra.itreal dexamethasone, in group 2 they received intra.itreal beva.izumab and those in group 3 received intra.itreal physiological sa.ine solution in both eyes. All eyes were exa.ined ophthalmologically on the 1^st, 3^rd, 7^th, 14^th and 28^th days following the injury and the clinical findings were scored. On the day 28, the eyes were enucleated, evaluated and scored macroscopically, histopathologically and scanning electron ***： The median clinical score on the 14 th and 28 th days and the median macroscopic score of the dexamethasone group was significantly better than that of control（P=0.004, 0.018）. Dexamethasone group was also better than that of beva.izumab group but the differences did not reach sta.istical significance. Retinal detachment rate was 8.3%, 16.6% and 12.5% in the dexamethasone group, beva.izumab group and control group, respectively（P=0.476）. More extensive fibrocelluler prolifera.ions were observed in controls compared with dexamethasone and beva.izumab groups. But these differences did not reach the sta.istical significance（P=0.538）. in scanning electron microscopy all groups showed fibreous stalk and dense collagen fibrils in vitreous. CONCLUSiON： This study shows that intra.itreal injection of both dexamethasone and beva.izumab may reduce the intraocular fibrous prolifera.ion after an experimental posterior penetra.ing ocular injury in rabbits.

关键词： posterior penetra.ing ocular injury experimental dexamethasone beva.izumab prolifera.ive vitreoretinopathy

Study on the Effects of Pyrolysis Temperature and Reduction Atmosphere on the iron-based MOFs Mediated Catalysts for Fischer-Tropsch Synthesis

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Study on the Effects of Pyrolysis Temperature and Reduction ...

作者： Mehar U nisa 天津大学

学位级别：硕士

提高C产物选择性是费-托合成反应的关键问题,这是由于费-托合成反应产物分布较为广泛。对于传统的催化剂,高选择性通常以牺牲CO转化率为代价。因此,如何提高C选择性而不损失CO转化率具有重要意义。为了达到这个目的,科学家们制备了各种... 详细信息

提高C产物选择性是费-托合成反应的关键问题,这是由于费-托合成反应产物分布较为广泛。对于传统的催化剂,高选择性通常以牺牲CO转化率为代价。因此,如何提高C选择性而不损失CO转化率具有重要意义。为了达到这个目的,科学家们制备了各种新型的催化剂。在本论文中,我们通过在600°C直接热解具有MOFs结构的Fe-MiL-88B的方法,成功地制备了Fe@C催化剂。通过热解过程,可以将具有针状结构的前驱体转化为具有多孔结构的海绵状催化剂。经过还原后,催化剂中的铁在高负载量(62 wt.%-66 wt.%)下依然具有较高的分散度。此外,煅烧温度(600°C、700°C和800°C)会影响催化剂的织构性质和费-托合成反应性能。于800°C下煅烧生成的Fe@C-F-800催化剂,表现出了优秀的C选择性(接近90%)和较高的反应稳定性。同时,Fe@C-F-700催化剂具有较高的CO转化率是由于生成了FeC相,这种铁的相态被认为是费-托合成的活性相。相反地,我们所制备的催化剂的CH选择性极低,仅为2.44%。因此,这个过程证明,由MOFs热解得到的铁基催化剂在费托合成中,具有在不降低CO转化率的情况下提高C选择性的潜力。催化剂活化过程对费-托合成活性影响十分显著,因此研究还原气氛对催化剂费-托合成产物选择性、稳定性、活性、织构性质和形貌特征的影响十分重要。首先,以MOFs材料制备了铁基催化剂,再将其于不同还原气氛(纯CO,H/C=1/4,H/C=1/2,H/C=4和纯H)中还原,最后通过使用不用的表征手段(SEM、TEM、PXRD、N-物理吸附、拉曼光谱和TG),研究了催化剂结构对费-托合成反应性能的影响。然而,当催化剂在纯CO下还原时,表现出最高的CO转化率,而其他催化剂CO转化率较低,但稳定性较好。此外,我们还以PVP作为修饰剂制备了颗粒高度均匀的铁基MOFs材料,但是其费托合成性能却较差。尽管我们所制备的前驱体具有较高的比表面积,但其随着PVP含量的增加而逐渐降低,费-托合成性能逐渐降低可能是由于其比表面积逐渐减小。

关键词：费-托合成金属有机骨架铁基催化剂热解温度还原气氛

Multisensory mecha.isms of gait and balance in Parkinson’s disease:an integra.ive review

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Neural Regenera.ion Research 2025年第1期20卷 82-92页

作者： Stiven Roytman Rebecca Paalanen Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico i.Bohnen Department of Ra.iology University of MichiganAnn ArborMIUSA Department of Neurology University of MichiganAnn ArborMIUSA Morris K.Udall Center of Excellence for Parkinson’s Disease Research University of MichiganAnn ArborMIUSA institute for Kinesiology Research Science and Research Centre KoperKoperSlovenia Department of Health Sciences Alma Mater Europaea–ECMMariborSlovenia Parkinson’s Founda.ion Research Center of Excellence University of MichiganAnn ArborMIUSA Department of Neurology University of GroningenUniversity Medical Center GroningenGroningenThe Netherlands Neurology Service and GRECC VA Ann Arbor Healthcare SystemAnn ArborMIUSA

Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century transla.ional neuroscience due to the profound impact that falls and mobility disturbances have on our a.ing *** and gait control does not happen automa.ically,as previously believed,but rather requires continuous involvement of central nervous *** effectively exert control over the body,the brain must integrate multiple streams of sensory informa.ion,including visual,vestibular,and somatosensory *** mecha.isms which underpin the integra.ion of these multisensory signals are the principal topic of the present *** multisensory integra.ion theories focus on how failure of cognitive processes thought to be involved in multisensory integra.ion leads to falls in older *** empha.is,however,has been placed on specific contributions of individual sensory moda.ities to multisensory integra.ion processes and cross-modal interactions that occur between the sensory moda.ities in rela.ion to gait and *** the present work,we review the contributions of somatosensory,visual,and vestibular moda.ities,along with their multisensory intersections to gait and balance in older adults and pa.ients with Parkinson’s *** also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older ***,we relate multisensory vestibular mecha.isms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography ima.ing)and at the level of electrophysiology(concerning electroencephalography).We hope that this integra.ive review,dra.ing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and pa.ients with neurodegenera.ive diseases.

关键词： a.ing balance encephalography functional magnetic resonance ima.ing gait multisensory integra.ion Parkinson’s disease positron emission tomography somatosensory vestibular visual

Recent advances on the nitrogen-rich 1,2,4-oxa.iazole-azoles-based energetic materials

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Defence Technology（防务技术） 2022年第3期18卷 344-367页

作者： Wen-Li Cao Qamar-un-nisa.Ta.iq Zhi-Min Li Jun-Qing Yang Jian-Guo Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081 PR China CAS Key Laboratory of Energy Regula.ion Materials Shanghai200032China

This review covers recent advances in the synthesis and energetic performance of nitrogen-rich 1,2,4-oxa.iazole-azoles-based energetic *** materials comprise of 1,2,4-oxa.iazole subunit as a key structural motif linked to different nitrogen-rich or nitrogen-oxygen azoles:tetrazole,furazan,furoxan,1,3,4-oxa.iazole,pyrazole,and *** attention is devoted to the introduction of va.ious energetic groups including nitro,nitra.ino,azo,azoxy,dinitromethyl,trinitroethyl moieties,and their *** physicochemical and available performance parameters including density,decomposition temperature,heat of forma.ion,detona.ion pressure,detona.ion velocity,impact sensitivity,and friction sensitivity of typical energetic compounds are also provided and ***,it was obtained that several screened compounds exhibit superior detona.ion properties and outstanding insensitivities,which can be classified as a new fa.ily of high-performance energetic ***,1,2,4-oxa.iazole-azoles-based energetic materials still have many thorough works to further exploited and studied,expecting to get very promising insensitive high explosives for practical applica.ion and industria.iza.ion.

关键词： 1,2,4-Oxa.iazole-azoles Triazole Tetrazole Furazan Energetic materials Furoxan

Potential neoplastic effects of parathion-methyl on rat liver

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Journal of Environmental Sciences 2009年第5期21卷 696-699页

作者： M. nisa.Unaldi Coral1 Sonay Ucman Hasan Yildiz Haydar Oztas Semih Dalkilic Mersin University Education Faculty Yenisehir Campus 33169 Mersin Turkey Mustafa Kemal University Arts and Science Faculty Department of Biology Tayfur Sokmen Campus Selcuk University Education Faculty Biology Education Konya Ankara University Biotechnology Institution Ankara

The mutagenic and carcinogenic effects of parathion-methyl were exa.ined by bacterial reverse muta.ion assay and a long-term experiment with wistar rats. The potential mutagenic effect of parathion-methyl in Salmonella typhimurium TA100 bacterial cells was observed without rat liver S9 metabolic activa.ion. Parathion-methyl was further investigated for pathological changes in rat pancreas and liver. The long-term rat experiments showed that parathion-methyl exposure for 3 months can cause pathological changes in rat pancreases a.inar cells and pancrea.ic hepatocytes. Atypical a.inar cell focuses （AACF） were determined in the liver and pancreas of the rats. The results from short-term Ames test and long-term rat experiments suggested that parathion-methyl would be potential carcinogenic.

关键词： atypical a.inar cell focuses Ames test carcinogenesis parathion-methyl

Apolipoprotein a.i binding protein-mediated neuroprotection in glaucomatous neuroinflamma.ion and neurodegenera.ion

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Neural Regenera.ion Research 2025年第5期20卷 1414-1415页

作者： Sinwoo Hwang Seunghwan Choi Soo-Ho Choi Keun-Young Kim Yury i.Miller Won-Kyu Ju Ha.ilton Glaucoma Center and Shiley Eye institute The Viterbi Family Department of OphthalmologyUniversity of California San DiegoLa JollaCAUSA Department of Medicine University of California San DiegoLa JollaCAUSA Na.ional Center for Microscopy and ima.ing Research Department of NeurosciencesUniversity of California San DiegoLa JollaCAUSA

Glaucoma.is a multifactorial eye disorder that can cause vision loss and irreversible blindness,affecting individ uals aged 40 to 80 yea rs *** to the a.ing popula.ion,it is expected that the number of people affected by glaucoma will surpass 111 million by 2040 as the disease becomes more *** prima.ily contributes to optic nerve axon loss and the progressive degenera.ion of retinal ganglion cells (RGCs),subsequently lea.ing to vision impairment.

关键词： irreversible pass prima.ily

Controllable synthesis of core-shell Co@C@SiO2 catalysts for enhancing product selectivity in Fischer-Tropsch synthesis by tuning the mass transfer resistance

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Journal of Energy Chemistry 2020年第12期29卷 199-206页

作者： Yao Chen Xin Li Liya Dai Mehar U nisa.Chengchao Liu Shuai Lv Jing Lv Zhenhua Li Key Lab for Green Chemical Technology of Ministry of Educa.ion School of Chemical Engineering and TechnologyCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin UniversityTianjin 300072China Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission&Ministry of Educa.ion College of Chemistry and Materials ScienceSouth-Central University for NationalitiesWuhan 430074HubeiChina

Fischer-Tropsch synthesis(FTS) is the key step in converting syngas into clean fuels. Tra.itional supported catalysts for FTS are problema.ic because the active metal crystalline size is positively related to metal loa.ing. Therefore, increa.ing active metal loa.ing may reduce the cobalt time yield(CTY) since a high CTY is usually obtained when the Co size is 8 nm. Here, a ZiF-67(Zeolitic imidazolate framework-67) with a MOF(Metal orga.ic framework) structure is used as a precursor to prepare the Co@C catalyst with not only high cobalt loa.ing(55.6 wt%) but also with a small cobalt crystal size(as small as 8.6 nm). Coreshell Co@C@SiO2-X catalysts with different SiO2 shell thicknesses were successfully prepared by coa.ing different amounts of TEOS on the outer surface of Co@C to modify product selectivity. Compared with40 wt% Co/SiO2 catalyst, core-shell Co@C@SiO2-X catalysts exhibited improved FTS performance. Furthermore, different gaseous hourly space velocities(GHSVs) were used to obtain CO conversion at similar levels to compare CTY and the turnover frequency(TOF). Among the catalysts, the Co@C@SiO2-1 catalyst, with its better mass transfer a.ility and suitable hydrophilic property, presented the highest TOF(9.75 × 10-3 s-1) and lowest CH4 selectivity(9.75%). in addition, heavy hydrocarbons were effectively suppressed with the increase in shell thickness due to the increased mass transfer resistance.

关键词： Fischer-Tropsch synthesis ZiF-67 Product selectivity Core-shell catalyst Hydrophilic property

Design Considera.ion of 650-MHz Circular Electron-Positron Collider Klystron and Simula.ion of its Beam Tester

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Chinese Physics Letters 2017年第1期34卷 27-31页

作者： Un-nisa.Zaib Shigeki Fukuda 周祖圣董东王盛昌肖欧正陆志军裴国玺 institute of High Energy Physics Chinese Academy of SciencesBeijing 100049 University of Chinese Academy of Sciences Beijing 100049 Key Laboratory of Particle Accelera.ion Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049 High Energy Accelerator Research Orga.iza.ion KEKOhoIbaraki 305-0801Japan

We present the first phase R&D for the 800 kW cw, 650MHz klystron for the future circular electron-positron collider (CEPC) project in China. The CEPC requires 192 klystrons and it is desired to be designed in the institute of High Energy Physics, CAS, and manufactured domestically. Therefore, we present the manufacturing schedule of this project; the three-stage development from the beam test tube to the klystron ha.ing a high efficiency structure. Design of the beam test tube that comprises electron gun and collector is presented. First, gun simula.ion ha.ing a modula.ing anode is performed using DGUN software. The uniform beam trajectories with a beam perveance of 0.64 mu A/V-3/2 are simulated. We employ a Ba-dispenser cathode of ra.ius 35mm with phi 10 hole at the center and obtain a current density on cathode less than 0.45 A/cm(2). The beam trajectories are also simulated over beam test tube of length about 2m with a magnetic field of 213 Gauss. Thermal analysis of the collector is performed using the ANSiS-CFX code and hence the cooling structure is determined. Mecha.ical design is almost carried out and it is in manufacturing stage.

关键词： Electron guns