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Towards a multiscale model of colorectal cancer

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World Journal of Gastroenterology 2007年第9期13卷 1399-1407页

作者： Ingeborg MM van Leeuwen Carina M Edwards mohammad ilyas Helen M Byrne Centre for Mathematical Medicine and Biology School of Mathematical Sciences University of Nottingham Nottingham NG7 2RD United Kingdom Centre for Mathematical Biology Oxford Centre for Industrial and Applied Mathematics Mathematical Institute University of Oxford Oxford OX1 3LB United Kingdom Division of Pathology School of Molecular Medical SciencesQueen’s Medical Centre University of Nottingham Nottingham NG7 2UHUnited Kingdom

Colorectal cancer (CRC) is one of the best characterised cancers, with extensive data documenting the sequential gene mutations that underlie its development. Complementary datasets are also being generated describing changes in protein and RNA expression, tumour biology and clinical outcome. Both the quantity and the variety of information are inexorably increasing and there is now an accompanying need to integrate these highly disparate datasets. In this article we aim to explain why we believe that mathematical modelling represents a natural tool or language with which to integrate these data and, in so doing, to provide insight into CRC.

关键词： Intestinal epithelium Crypt fission APC mutations Mathematical modelling Stem cell niche Wnt signalling

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ZrO2催化无溶剂条件下醇的液相氧化反应

催化学报 2007年第5期28卷 413-416页

作者： mohammad ilyas mohammad SADIQ Imdad KHAN 白沙瓦大学国家卓越物理化学研究中心白沙瓦25120巴基斯坦

采用一种环境友好的方法,以分子氧为氧化剂,以ZrO2为催化剂,在无溶剂的条件下实现了醇的选择性氧化.苯甲醛、环己酮和辛醛等是相应醇的主要氧化产物.考察了不同反应条件（搅拌速度、反应时间和温度）、催化剂制备参数（焙烧温度和负载... 详细信息

采用一种环境友好的方法,以分子氧为氧化剂,以ZrO2为催化剂,在无溶剂的条件下实现了醇的选择性氧化.苯甲醛、环己酮和辛醛等是相应醇的主要氧化产物.考察了不同反应条件（搅拌速度、反应时间和温度）、催化剂制备参数（焙烧温度和负载量）及氧分压等的影响.结果发现,对于醇氧化生成相应羰基化合物,1 223 K焙烧的ZrO2比723 K焙烧的ZrO2显示出更高的催化活性.催化剂在反应混合物中不溶解,可以通过简单的过滤使其分离并重复使用.当搅拌速度大于900 r/min时,对醇的转化速率无明显的影响.

关键词：氧化锆无溶剂液相氧化醇

Signaling mechanisms mediated by G-protein coupled receptors in human platelets

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Acta Pharmacologica Sinica 2004年第7期25卷 41-46页

作者： Sheikh Arshad SAEED,Huma RASHEED,Faisal A Wahed FECTO,mohammad ilyas ACHAKZAI,Rahmat ALI,John Dennis CONNOR,Anwar-ul-Hassan GILANI Department of Biological and Biomedical Sciences TheAga Khan University Karachi-74800 Pakistan Department of Biological and Biomedical Sciences TheAga Khan University Karachi-74800 Pakistan Department of Biological and Biomedical Sciences TheAga Khan University Karachi-74800 Pakistan Department of Biological and Biomedical Sciences TheAga Khan University Karachi-74800 Pakistan Department of Biological and Biomedical Sciences TheAga Khan University Karachi-74800 Pakistan Department of Biological and Biomedical Sciences TheAga Khan University Karachi-74800 Pakistan Department of Biological and Biomedical Sciences TheAga Khan University Karachi-74800 Pakistan

AIM: The present study deals with the investigation of mechanisms involved in the synergistic interaction between epinephrine and arachidonic acid (AA). METHODS: Venous blood was taken from healthy human volunteers reported to be free of medications for one week. Platelet aggregation was monitored at 37oC using Dual-channel Lumi-aggregometer. The resulting aggregation was recorded for 5 min by the measurement of light transmission as a function of time. RESULTS: The data show that a synergism in platelet aggregation mediated by subthreshold concentrations of epinephrine (1 μmol/L) and AA (0.2 μmol/L) was inhibited by the α2-receptor antagonist (yohimbine, IC50=0.6 μmol/L) and an inhibitor of AA-cyclooxygenase (COX), indomethacin (IC50=0.25 μmol/L). In examining receptor influence on intraplatelet signalling pathways, it was found that the synergistic effect was inhibited by calcium channel blockers, verapamil (IC50=0.4 μmol/L) and diltiazem (IC50=2.5 μmol/L), as well as by low concentrations of inhibitors of phospholipase C (PLC) (U73122; IC50=0.2 μmol/L) and mitogens activated protein kinase (MAPK) (PD 98059; IC50=3.8 μmol/L). Herbimycin A, a specific inhibitor of tyrosine light chain kinase (TLCK), showed inhibition at IC50 value of 15 μmol/L, whereas chelerythrine, a protein kinase C (PKC) inhibitor, had no effect up to 20 μmol/L. CONCLUSION: These data suggest that synergism between epinephrine and AA in platelet aggregation is triggered through receptors coupled to G-protein, which in turn, activate PLC, COX, and MAP kinase-signaling pathways.

关键词： platelet aggregation epinephrine arachidonic acid cyclooxygenase phospholipase C calcium channel blockers nitric oxide MAP kinase

Relation between Two Operator Inequalities <img src="http://***/***?f(B^{\frac{1}{2}}AB^{\frac{1}{2}})\geq&space;B^{-1}"title="f(B^{\frac{1}{2}}AB^{\frac{1}{2}})\geq B^{-1}"/>and <img src="http://***/***?A^{-1}\geq&space;g(A^{\frac{1}{2}}BA^{\frac{1}{2}})"title="A^{-1}\geq g(A^{\frac{1}{2}}BA^{\frac{1}{2}})"/>

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Advances in Pure Mathematics 2015年第2期5卷 93-99页

作者： mohammad ilyas Reyaz Ahmad Shadab ilyas Department of Mathematics Gaya College Gaya India Al-Ain University of Science and Technology Al Ain UAE Department of Information Technology Gaya College Gaya India

We shall show relation between two operator inequalities ?and for positive, invertible operators A and B, where f and g are non-negative continuous invertible functions on satisfying f(t)g(t)=t-1 .

关键词： Operator Inequality Orthoprojection Representing Function

Exploring the Catalytic Activity of Zirconia, Zirconia Supported Metals and Metal Oxides for Oxidation of Phenol

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Modern Research in Catalysis 2012年第2期1卷 23-27页

作者： mohammad Sadiq mohammad ilyas Department of Chemistry University of Malakand Chakdara Dir (Lower) Khyber Pakhtunkhwa Pakistan National Centre of Excellence in Physical Chemistry University of Peshawar Peshawar Pakistan

Catalytic oxidation/degradation of phenol with molecular oxygen in aqueous medium by Zirconia, zirconia supported metals and metal oxides at low temperature were studied in a three necked batch reactor. The catalysts prepared were characterized by modern techniques like XRD, SEM and EDX. The activities of different catalysts for the oxidation of phenol in aqueous medium were found to be in the order;Pt-Pd/ZrO2 > Bi-Pt/ZrO2 > Bi-Pd/ZrO2> Pt/ZrO2 > Pd/ZrO2 > Cu/ZrO2> Mn/ZrO2 > Bi/ZrO2. The enhanced catalytic activity of Bi-Pt/ZrO2 is attributed to Bi which in contact with Pt particles promotes its catalytic activity. In short, catalytic oxidation was found to be an effective tool, for the removal of phenol, from industrial waste water.

关键词： Oxidation Phenol Bismuth Platinum Zirconia

Synthesis and Characterization of Iron Oxide Nanoparticles Supported on Ziconia and Its Application in the Gas-Phase Oxidation of Cyclohexanol to Cyclohexanone

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Modern Research in Catalysis 2014年第1期3卷 12-17页

作者： mohammad Sadiq Gul Zamin Razia mohammad ilyas Department of Chemistry University of Malakand Chakdara Dir (L) Khyber Pakhtunkhwa Pakistan National Center of Excellence in Physical Chemistry University of Peshawar Khyber Pakhtunkhwa Pakistan

Iron oxide nanoparticles supported on zirconia were prepared by precipitation-deposition method and characterized by XRD, SEM, FT-IR, TGA/DTA, surface area and particle size analysis. Catalytic activities of the catalysts were tested in the gas-phase conversion of cyclohexanol in a fixed-bed flow type, Pyrex glass reactor, at 433 - 463 K. Major detected products were cyclohexanone, cyclohexene and benzene, depending on the used catalyst. The rate of reaction was significantly raised by the introduction of molecular oxygen in the feed gas, thereby suggesting the oxidation of cyclohexanol to cyclohexanone. Furthermore, the catalytic activity of iron oxide nanoparticles supported on zirconia treated with hydrogen at 553 K for 2 hours, was more selective and better than the unreduced iron oxide nanoparticles supported on zirconia, in the gas-phase oxidation of cyclohexanol to cyclohexanone. Experimental results showed that there was no leaching of metal, and that the catalyst was thus truly heterogeneous.

关键词： Iron Oxide Nanoparticles Magnetite Cyclohexanol

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基于循环神经网络改进雷达定量估测强降水

中国科技论文 2020年第5期15卷 585-592页

作者：郑玉魏鸣李南 Abro mohammad ilyas 南京信息工程大学气象灾害预报预警与评估协同创新中心南京210044 信德省文化教育部巴基斯坦卡拉奇74000

为了解决天气雷达传统定量估测强降水有较大偏差的问题,基于循环神经网络(recurrent neural network,RNN)模型,提出了一种有效的雷达估测强降水方法。基于对降水演变规律的认识,重新设计RNN结构,实现了对前3个时次雨量计降水的耦合,从... 详细信息

为了解决天气雷达传统定量估测强降水有较大偏差的问题,基于循环神经网络(recurrent neural network,RNN)模型,提出了一种有效的雷达估测强降水方法。基于对降水演变规律的认识,重新设计RNN结构,实现了对前3个时次雨量计降水的耦合,从而改善天气雷达估测强降水的效果。利用连续观测的雷达资料,结合前3个时次雨量计对地面降水量进行估测,解决了利用Z-R关系估测强降水时存在较大偏差的问题。利用2015年夏季降水测试数据集进行验证,并与滚动法建立的Z-R关系方法进行了对比,结果表明,在≥30 mm/h的强降水下,RNN估测降水方法相比Z-R关系方法的均方根误差(root mean square error,RMSE)降低了24.28%,中位绝对误差(median absolute error,Median AE)降低了32.83%。因此,循环神经网络估测降水方法对于定量估测强降水效果显著,具有业务应用价值。

关键词：天气雷达强降水估测循环神经网络耦合雨量计模型

晴空回波的大气风温湿结构及双偏振雷达参量分析

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气象 2018年第4期44卷 526-537页

作者：黄琴魏鸣胡汉峰 ABRO mohammad ilyas 南京信息工程大学、气象灾害预报预警与评估协同创新中心南京210044 中国气象局气溶胶与云降水重点开放实验室、南京信息工程大学南京210044

晴空回波有助于认识大气的风温湿结构,双偏振多普勒天气雷达为探测晴空大气提供了丰富信息。本文以2015年夏季南京信息工程大学C波段双偏振雷达探测的晴空回波为例,结合探空资料分析大气风温湿结构及晴空回波的影响因素,分析了晴空大气... 详细信息

晴空回波有助于认识大气的风温湿结构,双偏振多普勒天气雷达为探测晴空大气提供了丰富信息。本文以2015年夏季南京信息工程大学C波段双偏振雷达探测的晴空回波为例,结合探空资料分析大气风温湿结构及晴空回波的影响因素,分析了晴空大气的反射率因子Z、径向速度Vr以及差分反射率因子ZDR回波特征。研究表明:大气温、压、湿梯度造成折射指数分布不均以及背景风场引起的湍流增强,均可造成晴空回波,其回波机理为湍流散射;差分反射率因子受到多普勒效应的影响;在风场及大气湍团干湿特性不同的情况下,晴空回波的差分反射率因子呈现不同的特征。研究结果有益于深入认识大气风温湿结构特征对雷达电磁波的散射的影响以及雷达资料质量控制。

关键词：晴空回波双偏振雷达湍流散射大气风温湿结构

基于变分技术的天气雷达速度退模糊算法的改进研究

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气象与环境学报 2019年第3期35卷 18-28页

作者：吴彬魏鸣李艳芳郑石 ABRO mohammad ilyas 湖州市气象局浙江湖州313000 南京信息工程大学气象灾害预报预警与评估协同创新中心江苏南京210044 辽宁省气象装备保障中心辽宁沈阳110166

为有效地识别和提取多普勒天气雷达风场信息,对Gao和Droegemeier提出的基于变分技术的多普勒雷达径向速度数据退模糊方法进行了改进。原方法中将背景风场、方位和径向速度距离梯度信息同时作为约束条件,对Nyquist数进行校正。但是该方... 详细信息

为有效地识别和提取多普勒天气雷达风场信息,对Gao和Droegemeier提出的基于变分技术的多普勒雷达径向速度数据退模糊方法进行了改进。原方法中将背景风场、方位和径向速度距离梯度信息同时作为约束条件,对Nyquist数进行校正。但是该方法在迭代过程中使用了大量的数值分析和偏微分方程计算,造成径向速度场过度平滑和数据失真。针对这个问题,改进算法在得到径向速度分析场后,结合原始径向速度观测场,通过图像变化检测法,自动识别存在速度模糊的区域及计算需要校正的Nyquist数,对观测场的模糊区域进行校正。利用强对流天气和台风过程的雷达体扫数据验证了改进算法的可行性,并与原始算法及业务应用的WSR-88D算法对比。结果表明:改进算法有效地解决了原始算法中的不足,恢复真实的风场结构和分布特征,改善了退速度模糊的质量,从而得到更为合理的径向速度观测场;并且该算法退模糊效果优于WSR-88D算法,有助于为科研和业务应用服务。

关键词：变分技术天气雷达速度退模糊图像变化检测法