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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 Karachi-74800 Pakistan TheAga Khan University

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

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巴阿关系在美国撤军后的展望

巴阿关系在美国撤军后的展望

作者： arshad Khan 吉林大学

学位级别：硕士

探索巴基斯坦和阿富汗之间复杂而具有挑战性的关系一直是南亚地区最关键的问题之一。这项研究旨在调查2001年至2021年美国从阿富汗撤军后改善阿富汗与巴基斯坦关系的潜力。美军从阿富汗撤军为重塑阿富汗-巴基斯坦关系的未来创造了机会,... 详细信息

探索巴基斯坦和阿富汗之间复杂而具有挑战性的关系一直是南亚地区最关键的问题之一。这项研究旨在调查2001年至2021年美国从阿富汗撤军后改善阿富汗与巴基斯坦关系的潜力。美军从阿富汗撤军为重塑阿富汗-巴基斯坦关系的未来创造了机会,开启了南亚地区历史的新篇章。2001年,受在美国纽约市世贸中心爆发的9·11恐怖袭击的影响,以美国为首的联军入侵阿富汗,目的是消灭在该国避难的塔利班政府和基地组织的恐怖分子。巴基斯坦与阿富汗的边界漏洞,成为美国领导的反恐战争的重要参与者。受历史、文化、种族和政治差异等多种因素的影响,使巴基斯坦与阿富汗之间的关系变得复杂。阿富汗一直指责巴基斯坦为塔利班武装分子提供庇护,并支持塔利班武装分子进行反对阿富汗政府的叛乱活动。相反,巴基斯坦指责阿富汗为俾路支分裂分子和巴基斯坦塔利班组织(TTP)这类反巴基斯坦激进分子提供避难所。美国领导的阿富汗战争给巴基斯坦与阿富汗之间的关系带来了新的活力。巴基斯坦在支持美国领导的联军在阿富汗的军事行动方面发挥了关键作用,它支持了联军在阿富汗的军事行动。然而,巴基斯坦对美国领导的战争的支持遭到了美国和阿富汗的批评,因为该国在消除其部落地区的塔利班保护区方面做得不够好。20年来,由美国领导的联军在阿富汗进行了军事行动,为这场冲突投入了大量的军事力量和物质资源。尽管做出了这些努力,但随着塔利班的叛乱活动变得越来越猖狂,阿富汗政府仍然表现得软弱和分裂,阿富汗冲突并没有得到持久性的解决。2021年,美国宣布计划从阿富汗撤军,这标志着美国对阿富汗漫长的军事干预的结束。这次撤军给阿富汗与巴基斯坦的双边关系带来了一系列新的挑战和机遇。塔利班现在已经控制了阿富汗,组建了一个新的政府。巴基斯坦主张在阿富汗建立一个包容性的政府,所有少数民族和政治集团都参与其中。美国撤军后,阿富汗与巴基斯坦关系的前景取决于很多因素。其中最关键的因素之一是塔利班与巴基斯坦的联系。巴基斯坦一直与塔利班保持着密切的联系,并被指控为塔利班提供庇护和支持。然而,塔利班的掌权给巴基斯坦带来了新的挑战。阿富汗塔利班政府在妇女权利和国际关系等问题上的政策预计会受到国际社会的审查,而巴基斯坦与塔利班的联系可能会变得更加复杂。此外,阿富汗政府对巴基斯坦的立场也将影响双边关系的走向。过去,阿富汗政府曾指责巴基斯坦协助塔利班叛乱,使两国关系紧张。塔利班政府与巴基斯坦的关系可能会影响阿富汗政府在巴基斯坦上的立场,一个友好的塔利班政府可能会实现两国关系的改善。最后,中国和印度等地区参与者的作用将有助于塑造阿富汗与巴基斯坦关系的未来。这两个国家在该地区具有重大的经济和战略利益,并参与了旨在促进阿富汗稳定和发展的各种国际倡议。中国在该地区发挥着关键作用,在阿富汗投资了多个基础设施项目。巴基斯坦和阿富汗之间的关系是错综复杂的,充满了历史和地缘政治的复杂性。在过去的20年里,美国一直在积极参与该地区,特别是在阿富汗,自2001年以来,美国的军事存在一直是阿富汗冲突的关键性特征。然而,随着美国最近从阿富汗撤军,在美国撤军时期审视阿富汗与巴基斯坦关系的前景至关重要。2001年美国入侵阿富汗,对阿富汗与巴基斯坦的关系产生了重大影响。巴基斯坦成为美国领导的反恐战争的前线国家,为美国打击塔利班的军事行动提供了至关重要的支持。然而,尽管有这种支持,巴基斯坦与阿富汗的关系依旧紧张,因为巴基斯坦曾被认为是对塔利班和其他极端组织提供了援助。在美国撤军后的时期,有几个因素可能会影响阿富汗与巴基斯坦的关系。阿富汗的安全局势至关重要,人们担心塔利班重新掌权可能会再次使阿富汗成为基地组织和伊斯兰国等恐怖组织的避风港。这是巴基斯坦的一个重大安全关切,因为巴基斯坦以前曾是这些恐怖组织发动袭击的目标。杜兰德线的问题是另一个可能影响阿富汗与巴基斯坦的关系的因素。阿富汗从未承认杜兰德线是国际边界,这导致了两国之间的持续紧张关系。随着塔利班掌权,人们担心他们可能会再次提出这个问题,导致局势的紧张。此外,国际社会对阿富汗的人道主义局势十分关注,特别是对该国妇女和少数民族的待遇。这是巴基斯坦的一个重大民族关切,那里有大量的普什图人,与阿富汗的普什图人有着共同的种族和文化联系。美国撤军后,阿富汗与巴基斯坦关系的未来仍充满不确定性,由于塔利班重新掌权,两国之间的紧张关系可能会加剧。然而,两国也有机会在解决恐怖主义和极端主义等共同问题上进行合作。一个潜在的合作领域可能是边界管理,这一直是阿富汗与巴基斯坦都关注的一个问题。巴基斯坦和阿富汗之间漏洞百出的边境已经被恐怖分子和走私者利用。在塔利班的控制下,两国可能有机会共同努力,加强边境管理,打击恐怖分子和走私者的越境行动。

关键词：巴阿关系美国撤军美国撤军后反恐战争边境管理

Numerical and experimental study of wave shaper effects on detonation wave front

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Defence Technology（防务技术） 2018年第1期14卷 45-50页

作者： Khalid Naeem arshad Hussain SCME (NUST) Islamabad Simulation Lab.Room 113 SCME NUST H-12 Campus SCME (NUST) H-12 Campus

In the current study, streak camera was used to find concentricity of the assembly during detonation,investigate and compare shock front within the high explosive and behavior of the shock front on the surface of the liner, one containing wave shaper and the other without wave shaper. Streaks revealed that the whole assembly was concentric till the formation of the jet. Observed streaks vindicate the uniform propagation of shock front in both the cases. Results obtained for shock front velocities are in agreement with those obtained from simulations. In the presence of wave shaper higher shock front velocity was observed both in simulation and experiment. Simulation without wave-shaper showed that shock front struck the copper cone at grazing angle while in the presence of wave-shaper it struck at an angle of 125.

关键词： Shock front Streak camera Simulation Wave shaper

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Evaluation of soil loss severity and ecological restoration approach for sustainable agriculture in the Hindu Kush, Karakoram and Himalaya region

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Journal of Mountain Science 2024年第5期21卷 1509-1521页

作者： arshad ASHRAF Imran AHMAD Climate Energy and Water Research InstituteNational Agricultural Research Centre(NARC)Islamabad 44000Pakistan

Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation(RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., 100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic development in the region in future.

关键词： Climate change Erodibility Indus basin Land degradation Slope stabilization

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Detection of Lung Nodules on X-ray Using Transfer Learning and Manual Features

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Computers, Materials & Continua 2022年第7期72卷 1445-1463页

作者： Imran arshad Choudhry Adnan N.Qureshi Faculty of Information Technology University of Central PunjabLahorePakistan

The well-established mortality rates due to lung cancers,scarcity of radiology experts and inter-observer variability underpin the dire need for robust and accurate computer aided diagnostics to provide a second opinion.To this end,we propose a feature grafting approach to classify lung cancer images from publicly available National Institute of Health(NIH)chest X-Ray dataset comprised of 30,805 unique patients.The performance of transfer learning with pre-trained VGG and Inception models is evaluated in comparison against manually extracted radiomics features added to convolutional neural network using custom layer.For classification with both approaches,Support VectorsMachines(SVM)are used.The results from the 5-fold cross validation report Area Under Curve(AUC)of 0.92 and accuracy of 96.87%in detecting lung nodules with the proposed method.This is a plausible improvement against the observed accuracy of transfer learning using Inception(79.87%).The specificity of allmethods is>99%,however,the sensitivity of the proposed method(97.24%)surpasses that of transfer learning approaches(<67%).Furthermore,it is observed that the true positive rate with SVM is highest at the same false-positive rate in experiments amongst Random Forests,Decision Trees,and K-Nearest Neighbor classifiers.Hence,the proposed approach can be used in clinical and research environments to provide second opinions very close to the experts’intuition.

关键词： Lungs cancer convolutional neural network hand-crafted feature extraction deep learning classification

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骚扰摇蚊的生态学研究概况

中国媒介生物学及控制杂志 1993年第4期4卷 318-320页

作者：薛瑞德 arshad ali 军事医学科学院微生物流行病研究所北京100071 佛罗里达大学粮农研究所 sanfordfl32771

摇蚊(Chironomid midge)俗称盲蚊,属于双翅目摇蚊科的全变态昆虫。迄今世界上已知有5000余种,我网已知仅150余种,据我国学者初步估计,可能分布有1200余种。摇蚊的研究历史悠久,据1992年《Newsletter of Chironomid Research》介绍,到199... 详细信息

摇蚊(Chironomid midge)俗称盲蚊,属于双翅目摇蚊科的全变态昆虫。迄今世界上已知有5000余种,我网已知仅150余种,据我国学者初步估计,可能分布有1200余种。摇蚊的研究历史悠久,据1992年《Newsletter of Chironomid Research》介绍,到1991年底有1.2万余篇关于摇蚊的文献,现正编写文献目录。

关键词：骚扰摇蚊生态学摇蚊科

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Predicting Age and Gender in Author Profiling: AMulti-Feature Exploration

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Computers, Materials & Continua 2024年第5期79卷 3333-3353页

作者： Aiman Muhammad arshad BilalKhan Sadique Ahmad Muhammad Asim Department of Computer Science City University of Science and Information TechnologyPeshawar25000Pakistan EIAS:Data Science and Blockchain Laboratory College of Computer and Information SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia School of Computer Science and Technology Guangdong University of TechnologyGuangzhou510006China

Author Profiling (AP) is a subsection of digital forensics that focuses on the detection of the author’s personalinformation, such as age, gender, occupation, and education, based on various linguistic features, e.g., stylistic,semantic, and syntactic. The importance of AP lies in various fields, including forensics, security, medicine, andmarketing. In previous studies, many works have been done using different languages, e.g., English, Arabic, French,etc.However, the research on RomanUrdu is not up to the mark.Hence, this study focuses on detecting the author’sage and gender based on Roman Urdu text messages. The dataset used in this study is Fire’18-MaponSMS. Thisstudy proposed an ensemble model based on AdaBoostM1 and Random Forest (AMBRF) for AP using multiplelinguistic features that are stylistic, character-based, word-based, and sentence-based. The proposed model iscontrasted with several of the well-known models fromthe literature, including J48-Decision Tree (J48),Na飗e Bays(NB), K Nearest Neighbor (KNN), and Composite Hypercube on Random Projection (CHIRP), NB-Updatable,RF, and AdaboostM1. The overall outcome shows the better performance of the proposed AdaboostM1 withRandom Forest (ABMRF) with an accuracy of 54.2857% for age prediction and 71.1429% for gender predictioncalculated on stylistic features. Regarding word-based features, age and gender were considered in 50.5714% and60%, respectively. On the other hand, KNN and CHIRP show the weakest performance using all the linguisticfeatures for age and gender prediction.

关键词： Digital forensics author profiling for security AdaBoostM1 random forest ensemble learning

Analysis of Cognitive Radio Enabled Flooding in Opportunistic Networks

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International Journal of Communications, Network and System Sciences 2014年第7期7卷 212-222页

作者： Muhammad arshad Islam Marcel Waldvogel Computer Science Department University of Konstanz Konstanz Germany Department of Computer Science Mohammad Ali Jinnah University Islamabad Pakistan

Epidemic routing (Flooding) is considered as a simple routing protocol for opportunistic networks where the participants attempt to transmit whatever information they have to everyone who does not already have that information. However, it is plagued with disadvantages of resource scarcity as it exerts stress on available bandwidth as well as storage capacity of the devices in the network. Cognitive radio (CR) is one of the emerging technologies that can improve the bandwidth utilization by smart allocation of spectrum radio bands. Ideally speaking, a spectrum-aware cognitive radio is able to sense the local spectrum usage and adapt its own radio parameters accordingly. In this study, we have performed experiments to analyze the gains achieved by flooding protocol using cognitive radios of varying capabilities in opportunistic networks. We have performed experiments on three opportunistic networks obtained from real-life traces from different environments and presented results showing variance in delivery efficiency as well as cost incurred on those scenarios. Our results show that performance of flooding can be significantly improved using CRs in bandwidth-scarce environments;however, the improvement is not uniform with the increase in a number of available bands.

关键词： Opportunistic Networks Delay Tolerant Networks Flooding Cognitive Radio Simulation

Preparation and evaluation of vitamin E adjuvanted oil emulsified infectious bronchitis experimental vaccines

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Preparation and evaluation of vitamin E adjuvanted oil emuls...