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Advances in Biological Chemistry 2012年第2期2卷 152-159页

作者： hassan zanna A. J. Nok S. Ibrahim H. M. Inuwa Department Department of Biochemistry University of Maiduguri Maiduguri Nigeria Department of Biochemistry Ahmadu Bello University Zaria Nigeria

Cytosine Deaminase (CD) from Aspergillus parasiticus was purified and characterized. Time course for maximal CD production (50 μmol/min/mg) was at 72 hrs. The enzyme was purified 387.73 folds with an overall yield of 13%. The CD had pH optimum of 7.2, a temperature optimum of 40℃ - 45℃, activation of energy (Ea) of 8.4 KJ/mol and a t1/2 of 1.10 hr. A. parasiticus CD stoichiometrically deaminated Cyto-sine and 5-fluorocytosine (5-FC) with the KM values of 0.19mM and 0.30 mM respectively. Studies on the effect of pH on KM and Vmax gave pKa1 of 5.8 and pKa2 of 6.3 with enthalpy of ionization of 43.01 KJ/mole suggesting histidine in the active site. The enzyme was strongly inhibited by Ca2+, Co2+, Zn2+ and Hg2+ and completely inhibited by Cu2+ and Fe2+ at 50 mM. Therefore, A. parasiticus CD can be compared with CDs from other sources that are used in suicide gene therapy.

关键词： Cytosine Deaminase Cytosine 5-Fluorocytosine Aspergillus parasiticus Activation Energy

Acetic acid additive in NaNO_(3)aqueous electrolyte for long-lifespan Mg-air batteries

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Journal of Magnesium and Alloys 2024年第2期12卷 825-839页

作者： Yaqing Zhou Fan Sun Gunahua Lin Sandrine zanna Antoine Seyeux Philippe Marcus Jolanta´Swiatowska Chimie ParisTech-CNRS PSL UniversityInstitut de Recherche de Chimie Paris11 rue Pierre et Marie CurieParis 75005France

Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environmental sustainability,and ***,the fast hydrogen evolution reaction(HER)in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity,low energy density,and low ***,the conventionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additive as a corrosion inhibitor,therefore an electrolyte engineering for long-life time Mg-air batteries is *** resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching~1.8 V for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to over 360 h,in contrast to only~17 h observed in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid *** thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries.

关键词： Acetic acid additive in NaNO_(3)electrolyte Electrolyte engineering Corrosion surface film Surface characterization Hydrogen evolution

Detecting IEEE 802.11 Client Device Impersonation on a Wireless Access Point

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Journal of Communications and Information Networks 2022年第4期7卷 408-420页

作者： Paul zanna Dinesh Kumar Pj Radcliffe RMIT University MelbourneAustralia

The ability to effortlessly construct and broadcast false messages makes IEEE 802.11 wireless networks particularly vulnerable to *** frame generation allows rogue devices to impersonate an authorized user and issue commands that impact the user’s network connection or possibly the entire network’s ***,the current device impersonation detection methods are unsuitable for small devices or real-time *** contribution is to demonstrate that a rule-based learning classifier using several random forest(RF)features from an IEEE 802.11 frame can determine the probability that an impersonating device has generated that frame in real *** main innovation is a processing pipeline,and the algorithm that implements concurrent one-class classifiers on a per device basis yet is lightweight enough to run directly on a wireless access point(WAP)and produce real-time outputs.

关键词： IEEE 802.11 WIFI P4 software defined radio(SDR) software defined networking(SDN) security

Optimization, Spectroscopic(FT-IR, Excited States, UV/Vis) Studies, FMO, ELF, LOL, QTAIM and NBO Analyses and Electronic Properties of Two New Pyrimidine Derivatives

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Chinese Journal of Structural Chemistry 2019年第10期38卷 1615-1639,1609页

作者： SIYAMAK Shahab MASOOME Sheikhi LIUDMILA Filippovich zanna Ignatovich KONSTANTIN Laznev ALEXANDER Muravsky RADWAN Alnajjar SADEGH Kaviani Belarusian State University I SEI BSUMinskRepublic of Belarus Institute of Physical Organic Chemistry National Academy of Sciences of Belarus13 Surganov Str.Minsk 220072 Institute of Chemistry of New Materials National Academy of Sciences of Belarus36 Skarina Str.Minsk 220141 Young Researchers and Elite Club Gorgan BranchIslamic Azad UniversityGorganIran Department of Chemistry Faculty of ScienceUniversity of BenghaziBenghaziLibya Department of Chemistry University of Cape TownRondebosch 7701South Africa Department of Chemistry Ferdowsi University of MashhadMashhadIran

In the given research,the molecular structures of two new compounds,4-((E)-3-(dimethylamino)styryl)-6-((E)-4-(dimethylamino)styryl)pyrimidine-2-amine(PM-1)and N-(4-((E)-3-(dimethylamino)styryl)-6-((E)-4-(dimethylamino)styryl)pyrimidine-2-yl)-4,6-dichloro 1,3,5-1,3,5-triazin-2-amine(PM-2),have been studied with the use of density functional theory(DFT/B3LYP/MidiX)in dimethylformamide(DMF)for the first *** electronic spectra of the new compounds in a DMF solvent were carried out by temporally dependent density functional theory(TD-DFT)*** computed absorption spectral data of the title compounds are in good agreement with the experimental data,thus allowing an assignment of the UV/Vis *** equilibrium geometry,the HOMO and LUMO molecular orbitals,excitation energies,oscillator strengths and Natural Bond Orbital(NBO)analysis for the molecules have also been calculated and ***-IR spectra of the title molecules are recorded and *** electron location function(ELF),localized orbital locator(LOL)and quantum theory of atoms in molecules(QTAIM)analyses were also carried *** the basis of polyvinyl alcohol(PVA)and synthesized molecules,polarizer for UV/Vis region of the spectrum has been developed.

关键词： pyrimidine DFT UV/Vis spectrum TD-DFT polarization QTAIM analysis

Previous hepatitis B viral infection–an underestimated cause of pancreatic cancer

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World Journal of Gastroenterology 2022年第33期28卷 4812-4822页

作者： Sergey Batskikh Sergey Morozov Alexey Dorofeev zanna Borunova Dmitry Kostyushev Sergey Brezgin Anastasiya Kostyusheva Vladimir Chulanov Department of Hepatology Moscow Clinical Scientific Center N.A.A.S.LoginovMoscow 111123Russia Department of Gastroenterology Hepatology and NutritionFederal Research Center of NutritionBiotechnology and Food SafetyMoscow 115446Russia Department of Scientific and Clinical Laboratory Research Moscow Clinical Scientific Center N.A.A.S.LoginovMoscow 111123Russia Laboratory of Genetic Technologies Sechenov UniversityMoscow 119435Russia Division of Biotechnology Scientific Center for Genetics and Life SciencesSirius University of Science and TechnologySochi 354340Russia Laboratory of Genetic Technologies and Translational Research National Medical Research Center for Tuberculosis and Infectious Diseases of Ministry of Health of RussiaMoscow 127994Russia

BACKGROUND The etiology of pancreatic cancer remains unclear. This limits the possibility of prevention and effective treatment. Hepatitis B virus(HBV) is responsible for the development of different types of cancer, but its role in pancreatic cancer is still being *** To assess the prevalence of previous HBV infection and to identify viral biomarkers in patients with pancreatic ductal adenocarcinoma(PDAC) to support the role of the virus in etiology of this *** The data of 130 hepatitis B surface antigen-negative subjects were available for the final analysis,including 60 patients with PDAC confirmed by cytology or histology and 70 sex-and age-matched controls. All the participants were tested for HBV biomarkers in blood [antibody to hepatitis B core antigen(anti-HBc), antibody to hepatitis B surface antigen(anti-HBs) and HBV DNA], and for those with PDAC, biomarkers in resected pancreatic tissues were tested(HBV DNA, HBV pregenomic RNA and covalently closed circular DNA). We performed immunohistochemistry staining of pancreatic tissues for hepatitis B virus X antigen and Ki-67 protein. Non-parametric statistics were used for the *** Anti-HBc was detected in 18/60(30%) patients with PDAC and in 9/70(13%) participants in the control group(P = 0.029). Accordingly, the odds of PDAC in anti-HBc-positive subjects were higher compared to those with no previous HBV infection(odds ratio: 2.905, 95% confidence interval: 1.191-7.084, standard error 0.455). HBV DNA was detected in 8 cases of PDAC and in 6 of them in the pancreatic tumor tissue samples only(all patients were anti-HBc positive). Blood HBV DNA was negative in all subjects of the control group with positive results of the serum anti-HBc test. Among 9 patients with PDAC, 5 revealed signs of replicative competence of the virus(covalently closed circular DNA with or without pregenomic RNA) in the pancreatic tumor tissue samples. Hepatitis B virus X antigen expression and active cell

关键词： Hepatitis B virus Previous hepatitis B Occult hepatitis B virus infection Pancreatic cancer Pancreatic ductal adenocarcinoma

Philippine retinoblastoma initiative multi-eye center study 2010-2020

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 144-156页

作者： Roland Joseph D.Tan Gary John V.Mercado Patricia E.Cabrera Paulita Pamela P.Astudillo Rolando Enrique D.Domingo Josept Mari S.Poblete Charmaine Grace M.Cabebe Adriel Vincent R.Te Melissa Anne S.Gonzales Jocelyn G.Sy Beltran Alexis A.Aclan Jayson T.So Fatima G.Regala Kimberley Amanda K.Comia Josemaria M.Castro Mara Augustine S.Galang Aldous Dominic C.Cabanlas Benedicto Juan E.Aguilar Gabrielle S.Evangelista Jo Michael Maniwan Andrei P.Martin Calvin Y.Martinez John Alfred H.Lim Rena Ivy Bascuna Rachel M.Ng Kevin B.Agsaoay Kris zanna A.Acluba-Arao Ellaine Rose V.Apostol Beatriz M.Prieto Department of Ophthalmology and Visual Sciences Philippine General HospitalManila 1000Philippines Department of Ophthalmology Baguio General Hospital and Medical CenterBaguio City 2600Philippines Department of Ophthalmology Manila Doctors HospitalManila 1000Philippines Department of Ophthalmology Rizal Medical CenterPasig City 1600Philippines Department of Ophthalmology Jose B.Lingad Memorial Regional HospitalPampanga 2000Philippines Department of Ophthalmology Southern Philippines Medical CenterDavao City 8000Philippines Department of Ophthalmology East Avenue Medical CenterQuezon City 1100Philippines Department of Ophthalmology Northern Mindanao Medical CenterCagayan de Oro City 9000Philippines Department of Ophthalmology Cebu Velez General HospitalCebu City 6000Philippines Legazpi Eye Center Legazpi City 4500Philippines Department of Ophthalmology Cagayan Valley Medical CenterTuguegarao City 3500Philippines

AIM:To provide a comprehensive and more representative national data on the disease,especially on treatment options and outcomes,and to determine access of retinoblastoma patients from Luzon,Visayas and Mindanao to eye care,and determine if access is associated with delay in consultation,staging and ***:Cohort study of retinoblastoma patients seen in eleven institutions located in the three major areas of the Philippines namely Luzon,Vizayas and Mindanao from ***:Totally 636 patients,involving 821 eyes,were ***(57%)were from Luzon and were seen in institutions in Luzon(72%).Annually,58±10 new cases were seen with 71%having unilateral *** delay of consultation remained long at 9(3,17)mo,longest in patients with unilateral disease(P<0.02)and those from the Visayas(P<0.003).Based on the International Retinoblastoma Staging System,only 35%of patients had Stage 1 while 47%already had extraocular *** was the most common treatment received by 484 patients while intravenous chemotherapy was received by *** were 250(39%)patients alive,195(31%)dead,85(13%)abandoned,17(3%)refused and 89(14%)with no ***:This study presents the largest cohort of retinoblastoma patients in the Philippines in terms of patients’and participating institutions’number and geographical location and type of institution(private and public).It also presents more comprehensive data on the treatments used and outcomes(survival,globe salvage,and vision retention rates).Delay in consultation was still long among patients leading to advanced disease stage and lower survival *** increasing capacity to diagnose and manage retinoblastoma in the country,the delay of consultation remains long primarily due to accessibility issues to eye care institutions especially in the Visayas and financial *** delay was still significant that overall survival rate remain low.

关键词： retinoblastoma Philippines clinical profile

影响旅游目的地网站“黏性”的外部因素结构优化研究

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中国管理信息化 2017年第1期20卷 142-147页

作者： Musina zanna(梦竹) 高学东北京科技大学东凌经济管理学院北京100083

网站由多层面、多元素组成,这些都影响网站用户的满意度和相关行为。本文采用因子分析方法,探查影响旅游目的地网站"黏性"的外部因素结构及减少外部因素维度的变量数量。外部因素维度变量影响用户对网站的印象和兴趣。外部因素变量跟旅... 详细信息

网站由多层面、多元素组成,这些都影响网站用户的满意度和相关行为。本文采用因子分析方法,探查影响旅游目的地网站"黏性"的外部因素结构及减少外部因素维度的变量数量。外部因素维度变量影响用户对网站的印象和兴趣。外部因素变量跟旅游者旅游经验和知识有关。本文的研究结果达到新的更简单的外部因素结构,其包含输出四个因子,即"不想去的旅游地""有名气性的旅游地""旅游地与和网站的安全性"和"没去过的旅游地",这些因子对旅游网站"黏性"的强力评价起最好的作用。

关键词：网站评价外部因素维度因子分析网站“黏性” 旅游目的地

脂肪酸组合对体外瘤胃微生物发酵挥发性脂肪酸的影响

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中国畜牧兽医 2019年第10期46卷 2916-2926页

作者：习瓒娜高健王梦芝扬州大学动物科学与技术学院扬州225009 中国农业大学北京100089

为研究长链脂肪酸组合对体外培养瘤胃微生物发酵挥发性脂肪酸(VFA)的影响,并得出最优脂肪酸组合及添加水平,试验选取硬脂酸、油酸、亚油酸及α-亚麻酸4种脂肪酸因子,设置0.5%、1.0%、1.5%等3个水平进行L9(3^4)正交试验,其中Ⅰ~Ⅸ组为试... 详细信息

为研究长链脂肪酸组合对体外培养瘤胃微生物发酵挥发性脂肪酸(VFA)的影响,并得出最优脂肪酸组合及添加水平,试验选取硬脂酸、油酸、亚油酸及α-亚麻酸4种脂肪酸因子,设置0.5%、1.0%、1.5%等3个水平进行L9(3^4)正交试验,其中Ⅰ~Ⅸ组为试验组、Ⅹ组为对照组,各处理均设3个重复。以3头瘤胃瘘管山羊为瘤胃液供体进行体外发酵试验,测定各组培养液VFA 24 h内的动态变化。结果显示,各组的总挥发性脂肪酸(TVFA)浓度总体上呈先上升后下降再上升的波动变化趋势。其中在6 h时Ⅶ组TVFA浓度最高。乙酸/丙酸比值总体呈下降趋势,6 h前下降较快,6 h后趋于平缓。丁酸摩尔百分比在7.97%~15.41%间变动。主成分与最优组合分析表明,TVFA浓度影响的主次顺序为亚油酸、油酸、硬脂酸、α-亚麻酸;以添加1.5%硬脂酸、0.5%油酸、1.5%亚油酸、0.5%α-亚麻酸时组合效应最好。

关键词：长链脂肪酸组合瘤胃微生物发酵挥发性脂肪酸(VFA)

综合平衡法分析脂肪酸组合对瘤胃微生物蛋白合成的组合效应

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中国饲料 2021年第11期 12-19页

作者：习瓒娜高健戴乐军王梦芝扬州大学动物科学与技术学院江苏扬州225009 连云港生物工程中等专业学校江苏连云港222065

为研究不同脂肪酸组合对体外培养瘤胃微生物蛋白的影响,试验选取硬脂酸、油酸、亚油酸、ɑ-亚麻酸四种脂肪酸因子,设置0.5%、1.0%、1.5%这3个水平进行L9(34)正交试验,其中Ⅰ~Ⅸ为试验组、Ⅹ为对照组,各处理均设3个重复。以3头瘤胃瘘管... 详细信息

为研究不同脂肪酸组合对体外培养瘤胃微生物蛋白的影响,试验选取硬脂酸、油酸、亚油酸、ɑ-亚麻酸四种脂肪酸因子,设置0.5%、1.0%、1.5%这3个水平进行L9(34)正交试验,其中Ⅰ~Ⅸ为试验组、Ⅹ为对照组,各处理均设3个重复。以3头瘤胃瘘管山羊提供瘤胃液进行体外培养,测定各组培养液瘤胃发酵pH、氨氮(NH3-N)浓度、微生物蛋白(MCP)、原虫蛋白、细菌蛋白的含量。结果表明:在本试验条件下,不同脂肪酸组合对瘤胃pH、NH3-N浓度无显著影响(P>0.05),且皆处于瘤胃正常生长环境;不同脂肪酸组合对瘤胃微生物蛋白、原虫蛋白、细菌蛋白含量也无显著影响(P>0.05);主成分分析表明,在这四种不同脂肪酸中,ɑ-亚麻酸对微生物蛋白的调控效果好,脂肪酸组合效应为正组合效应。综上,脂肪酸组合对体外培养瘤胃微生物蛋白合成无明显影响。综合平衡分析表明,添加1.5%硬脂酸、1.0%油酸、0.5%亚油酸、1.5%ɑ-亚麻酸时,组合效应最好。

关键词：脂肪酸组合瘤胃发酵微生物蛋白原虫细菌

WFX-120B型原子吸收分光光度计主板故障维修一例

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