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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

Recent Developments in Authentication Schemes Used in Machine-Type Communication Devices in Machine-to-Machine Communication: Issues and Challenges

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Computers, Materials & Continua 2024年第4期79卷 93-115页

作者： Shafi Ullah Sibghat Ullah Bazai mohammad Imran Qazi Mudassar ilyas Abid Mehmood Muhammad Asim Saleem Muhmmad Aasim Rafique Arsalan Haider ilyas Khan Sajid Iqbal Yonis Gulzar Kauser Hameed Department of Computer Engineering Balochistan University of Information TechnologyEngineering and Management SciencesQuetta87300Pakistan Department of Information Technology Balochistan University of Information TechnologyEngineeringand Management SciencesQuetta87300Pakistan Department of Information Systems College of Computer Sciences and Information TechnologyKing Faisal UniversityHofuf in Al-Ahsa31982Saudi Arabia Department of Management Information Systems College of Business AdministrationKing Faisal UniversityHofuf in Al-Ahsa31982Saudi Arabia Department of Software Engineering College of ComputingRiphah International UniversityFaisalabad44000Pakistan Department of Electrical Engineering Balochistan University of Information Technology Engineeringand Management SciencesQuetta87300Pakistan Department of Mathematics College of Science Al-ZulfiMajmaah UniversityAl-Majmaah11952Saudi Arabia

Machine-to-machine (M2M) communication plays a fundamental role in autonomous IoT (Internet of Things)-based infrastructure, a vital part of the fourth industrial revolution. Machine-type communication devices(MTCDs) regularly share extensive data without human intervention while making all types of decisions. Thesedecisions may involve controlling sensitive ventilation systems maintaining uniform temperature, live heartbeatmonitoring, and several different alert systems. Many of these devices simultaneously share data to form anautomated system. The data shared between machine-type communication devices (MTCDs) is prone to risk dueto limited computational power, internal memory, and energy capacity. Therefore, securing the data and devicesbecomes challenging due to factors such as dynamic operational environments, remoteness, harsh conditions,and areas where human physical access is difficult. One of the crucial parts of securing MTCDs and data isauthentication, where each devicemust be verified before data transmission. SeveralM2Mauthentication schemeshave been proposed in the literature, however, the literature lacks a comprehensive overview of current M2Mauthentication techniques and the challenges associated with them. To utilize a suitable authentication schemefor specific scenarios, it is important to understand the challenges associated with it. Therefore, this article fillsthis gap by reviewing the state-of-the-art research on authentication schemes in MTCDs specifically concerningapplication categories, security provisions, and performance efficiency.

关键词： Authentication cyber security internet of things machine-type communication devices machine-to-machine communication

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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