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machine Learning Approach for COVID-19 Detection on Twitter

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Computers, materials & Continua 2021年第8期68卷 2231-2247页

作者： Samina Amin m.Irfan Uddin Heyam H.Al-Baity m.Ali Zeb m.abrar Khan Institute of Computing Kohat University of Science and TechnologyKohat26000Pakistan Department of Information Technology College of Computer and Information SciencesKing Saud UniversityRiyadh11543Saudi Arabia

Social networking services(SNSs)provide massive data that can be a very influential source of information during pandemic *** study shows that social media analysis can be used as a crisis detector(e.g.,understanding the sentiment of social media users regarding various pandemic outbreaks).The novel Coronavirus Disease-19(COVID-19),commonly known as coronavirus,has affected everyone worldwide in *** Twitter data have revealed the status of the COVID-19 outbreak in the most affected *** study focuses on identifying COVID-19 patients using tweets without requiring medical records to find the COVID-19 pandemic in Twitter messages(tweets).For this purpose,we propose herein an intelligent model using traditional machine learning-based approaches,such as support vector machine(SVm),logistic regression(LR),naïve Bayes(NB),random forest(RF),and decision tree(DT)with the help of the term frequency inverse document frequency(TF-IDF)to detect the COVID-19 pandemic in Twitter *** proposed intelligent traditional machine learning-based model classifies Twitter messages into four categories,namely,confirmed deaths,recovered,and *** the experimental analysis,the tweet data on the COVID-19 pandemic are analyzed to evaluate the results of traditional machine learning approaches.A benchmark dataset for COVID-19 on Twitter messages is developed and can be used for future research *** experiments show that the results of the proposed approach are promising in detecting the COVID-19 pandemic in Twitter messages with overall accuracy,precision,recall,and F1 score between 70%and 80%and the confusion matrix for machine learning approaches(i.e.,SVm,NB,LR,RF,and DT)with the TF-IDF feature extraction technique.

关键词： Artificial intelligence coronavirus COVID-19 pandemic social network Twitter machine learning natural language processing

Investigation of 50 Hz Pulsed DC Nitrogen Plasma with Active Screen Cage by Trace Rare Gas Optical Emission Spectroscopy

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Plasma Science and Technology 2014年第4期16卷 324-328页

作者： A.SAEED A.W.KHAN m.SHAFIQ F.JAN m.abrar m.ZAKA-UL-ISLAm m.ZAKAULLAH Department of Physics Gomal University Department of Physics Quaid-i-Azam University Department of Physics Hazara University Mansehra Plasmant Department of Chemistry Univesity of Antwerp campus DriEkin

Optical emission spectroscopy is used to investigate the nitrogen-hydrogen with trace rare gas （4% Ar） plasma generated by 50 Hz pulsed DC discharges. The filling pressure varies from 1 mbar to 5 mbar and the current density ranges from 1 mA-cm-2 to 4 ***-2. The hydrogen concentration in the mixture plasma varies from 0% to 80%, with the objective of identifying the optimum pressure, current density and hydrogen concentration for active species （[N] and IN2]） generation. It is observed that in an N2-H2 gas mixture, the concentration of N atom density decreases with filling pressure and increases with current density, with other parameters of the discharge kept unchanged. The maximum concentrations of active species were found for 40% H2 in the mixture at 3 mbar pressure and current density of 4 ***-2.

关键词： TRG-OES DC glow discharge reactive species

Antiepileptic activity of lobeline isolated from the leaf of Lobelia nicotianaefolia and its effect on brain GABA level in mice

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Asian Pacific Journal of Tropical Biomedicine 2012年第7期2卷 537-542页

作者： abrar m Tamboli Rukhsana A Rub Pinaki Ghosh SL Bodhankar Department of Pharmacognosy Allana College of PharmacyUniversity of Pune Department of Pharmacology Poona college of PharmacyBharati Vidyapeeth Deemed University

Objective:To investigate the anticonvulsant activity of the lobeline isolated from the Lobelia nicotianaefolia in chemoconvulsant-induced seizures and its biochemical mechanism by investigating relationship between seizure activities and altered gamma amino butyric acid(GABA)in brain of mice in Pentylenetetrazol(PTZ) seizure ***:The anticonvulsant activity of the isolated lobelinc(5,10,20 and 30 mg/kg.i.p.) was investigated in PTZ and strychnine induced seizures in mice and the effect of isolated lolieline on brain GABA level in seizures induced by *** was used as reference anticonvulsant drugs for ***:Isolated lobeliue(10,20 and 30 nig/***.) significautly delayed and antagonized(P mortality was also prevented in the test group of *** biochemical evaluation,isolated lolieline(5,10and 20 mg/kg,i.p.) significantly increased the brain GABA *** at dose of 30 mg/kg GABA level showed slight decrease in PTZ ***:In our findings,isolated lolieline(20mg/kg) exhibited potent anticonvulsant activity against PTZ induced *** a biochemical evaluation suggested significant increase in harain GABA level at 20 nig/kg *** isolated ***,we may propose that lolieline reduces epileptic seizures by enhancing the GABA release supporting the GABAergic mechanism.

关键词： Lobelia nicotianaefolia Lobeline Brain GABA level Antiepileptic activity Pentylenetetrazol(PTZ) Strychnine

微旋转切向双曲混合流体中悬浮混合纳米粒子的流变学

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Journal of Central South University 2023年第4期30卷 1231-1245页

作者： m.N.abrar Salah UDDIN Kamran AKHTAR Department of Civil Engineering National University of Sciences and TechnologyBalochistan Campus QuettaQuetta 86000Pakistan National University of Sciences and Technology Islamabad 44000Pakistan

流体运动通过线性拉伸片而实现。本研究结合多种流动和热现象,如多孔介质、倾斜磁流体、焦耳热以及速度和热滑移因子,用数值方法研究了切向双曲混合纳米流体通过多孔薄片的微旋转效应。得到的数学公式是一组非线性耦合偏微分方程。为了... 详细信息

流体运动通过线性拉伸片而实现。本研究结合多种流动和热现象,如多孔介质、倾斜磁流体、焦耳热以及速度和热滑移因子,用数值方法研究了切向双曲混合纳米流体通过多孔薄片的微旋转效应。得到的数学公式是一组非线性耦合偏微分方程。为了得到近似解,引入了相似性变量。利用Runge-Kutta-Fehlberg 45 (RKF-45)和射门技术,得到主导微分方程的数值解。用图示法表示相关参数的物理意义。为了验证数值结果,与已经发表的数据进行比较。假设流体的流速随Weissenberg数和渗透率的增加而减小,流体的角速度随表面条件参数的增加而明显著加快。表面摩擦因数随Weissenberg数的增加而有效减小,随大的速度滑移参数的增大而增大。结果证实,较高的银和铜纳米颗粒体积分数具有提高流动流体导热率的潜力。混合纳米流体可广泛应用在工程中,比如核冷却、海水淡化、机加工、制冷、热交换器、太阳能集热器和发动机冷却等。此外,在微旋转切向双曲流体中混入纳米流体可提高系统的热能力,可将其应用于依赖热传递的机械系统。

关键词：微极性流体混合纳米流体切向双曲流体多孔介质滑移因子倾斜磁流体

Optimization Study of Pulsed DC Nitrogen-Hydrogen Plasma in the Presence of an Active Screen Cage

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Plasma Science and Technology 2014年第5期16卷 460-464页

作者： A.SAEED A.W.KHAN F.JAN H.U.SHAH m.abrar m.ZAKA-UI-ISLAm m.KHALID m.ZAKAULLAH National Centre for Physics Quaid-i-Azam University Campus Islamabad Department of Physics Gomal University Department of Physics Quaid-i-Azam University Department of Physics Hazara University Mansehra Department of Physics Faculty of ScienceUniversity of Jazan

A glow discharge plasma nitriding reactor in the presence of an active screen cage is optimized in terms of current density,filling pressure and hydrogen concentrations using optical emission spectroscopy（OES）.The samples of AISI 304 are nitrided for different treatment times under optimum *** treated samples were analyzed by X-ray diffraction（XRD） to explore the changes induced in the crystallographic *** XRD pattern confirmed the formation of iron and chromium nitrides arising from incorporation of nitrogen as an interstitial solid solution in the iron lattice.A Vickers microhardness tester was used to evaluate the surface hardness as a function of treatment time（h）.The results showed clear evidence of improved surface hardness and a substantial amount of decrease in the treatment time compared with the previous work.

关键词： optical diagnostics plasma nitriding austenitic stainless steel

基于博弈论赋权的灌溉用水效率GRA-TOPSIS评价模型

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农业机械学报 2017年第5期48卷 218-226页

作者：刘东龚方华付强 FAIZ m abrar 李天霄崔嵩东北农业大学水利与土木工程学院哈尔滨150030 农业部农业水资源高效利用重点实验室哈尔滨150030

在构建区域灌溉用水效率综合评价指标体系的基础上,运用博弈论(Game theory,GT)思想将层次分析法(Analytic hierarchy process,AHP)所得主观权重与改进熵值法(Improved entropy value method,IEVm)所得客观权重进行综合集成以获取组合权... 详细信息

在构建区域灌溉用水效率综合评价指标体系的基础上,运用博弈论(Game theory,GT)思想将层次分析法(Analytic hierarchy process,AHP)所得主观权重与改进熵值法(Improved entropy value method,IEVm)所得客观权重进行综合集成以获取组合权值,并将灰色关联分析(Gray relation analysis,GRA)与逼近理想解排序(Technique for order preference by similarity to ideal solution,TOPSIS)相结合,以三江平原10个大型灌区为例进行验证,对区域灌溉用水效率作综合评价。采用Spearman等级相关系数检验灌溉水有效利用系数排序与GRA-TOPSIS法排序,得到的相关系数高达0.863,且GRA-TOPSIS法、GRA法、TOPSIS法对同一灌区综合排序的位次相差均不超过2,表明评价结果具有合理性和一致性;GRA-TOPSIS法所得综合值的极差为0.343,变异系数为0.267,均高于单独使用GRA法或TOPSIS法的极差与变异系数,更有利于对灌区灌溉用水效率进行辨识分区。此外,根据目标层与准则层排序差异度将灌区分为3类,辨识各灌区灌溉用水效率主控因子,对区域灌溉用水效率发展策略的制定具有参考价值。

关键词：灌溉用水效率大型灌区博弈论灰色关联分析逼近理想解排序综合评价

Influence of cold plasma treatment on insecticidal properties of wheat seeds against red flour beetles

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Plasma Science and Technology 2019年第8期21卷 97-102页

作者： S AFSHEEN U FATImA T IQBAL m abrar S mUHAmmAD A SAEED m ISA m F mALIK S SHAmAS Department of Zoology Faculty of ScienceUniversity of GujratHafiz Hayat CampusGujrat50700Pakistan Department of Physics Faculty of ScienceUniversity of GujratHafiz Hayat CampusGujrat50700Pakistan3Department of PhysicsHazara University MansehraMansehra21300Pakistan4Department of PhysicsGovernment College Women UniversitySialkot51310Pakistan

For the long-term fortification of warehoused crops, the insecticidal impact of cold plasma treated wheat seeds against red flour beetles are *** this study, the gain weight loss,mortality and repellency tests of cold plasma treated seeds are investigated and statistical analysis is carried out by SPSS *** plasma treatment is carried out at 800 V for 1 and 4 *** results show that the minimum grain weight loss is observed in plasma treated seeds as compared to controlled *** is also observed that the mortality rate is minimum in the controlled seed while maximum at 4 min plasma ***, the repellent effect has a very small variation as compared to the controlled seed for Tribolium ***, plasma treatment can be considered as a practical and effective method for seed protection against red floor beetles particularly during long-term storage by controlling the insecticidal effects.

关键词： cold plasma mortality repellency grain weight loss quality stored seeds protection

Adherence to Advisory Committee on Immunization Practices in diabetes mellitus patients in Saudi Arabia:A multicenter retrospective study

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World Journal of Diabetes 2024年第3期15卷 440-454页

作者： Saleh Fahad Alqifari Aya K Esmail Dalal m Alarifi Ghalya Y Alsuliman maram m Alhati may R mutlaq mohammed Aldhaeefi Shaden A Alshuaibi Palanisamy Amirthalingam abrar Abdallah Afaf S Wasel Heba R Hamad Shoroq Alamin Tasneem H Atia Tariq Alqahtani Department of Pharmacy Practice University of TabukTabuk 71491Saudi Arabia Department of Clinical Sciences Sulaiman Alrajhi UniversityQassim 52726Saudi Arabia Department of Family medicine International Medical CenterJeddah 23214Saudi Arabia Clinical and Administrative Pharmacy Sciences College of PharmacyHoward UniversityWashingtonDC 20059United States Department of Pharmacology King Saud Bin Abdulaziz University for Health SciencesKing Abdullah International Medical Research CenterRiyadh 11481Saudi Arabia

BACKGROUND Patients with diabetes mellitus(Dm)are predisposed to an increased risk of infection signifying the importance of vaccination to protect against its potentially severe *** Centers for Disease Control and Prevention/Advisory Committee on Immunization Practices(CDC/ACIP)issued immunization recommendations to protect this patient *** To assess the adherence of patients with Dm to the CDC/ACIP immunization recommendations in Saudi Arabia and to identify the factors associated with the vaccine adherence *** An observational retrospective study conducted in 2023 was used to collect data on the vaccination records from 13 diabetes care centers in Saudi Arabia with 1000 eligible patients in phase I with data collected through chart review and 709 patients in phase II through online *** Among participants,10.01%(n=71)had never received any vaccine,while 85.89%(n=609)received at least one dose of the coronavirus disease 2019(COVID-19)vaccine,and 34.83%(n=247)had received the annual influenza *** 2.96%(n=21),2.11%(n=15),and 1.12%(n=8)received herpes zoster,tetanus,diphtheria,and pertussis(Tdap),and human papillomavirus(HPV)vaccines,*** patients with Dm in Saudi Arabia,the rate of vaccination for annual influenza and COVID-19 vaccines was higher compared to other vaccinations such as herpes zoster,Tdap,pneumococcal,and *** such as vaccine recommendations provided by family physicians or specialists,site of care,income level,Dm-related hospitalization history,residency site,hemoglobin A1c(HbA1c)level,and health sector type can significantly influence the vaccination rate in patients with *** non-vaccinated patients with Dm,the most reported barriers were lack of knowledge and fear of side *** signifies the need for large-scale research in this area to identify additional factors that might facilitate adherence to CDC/ACIP vaccine recommendations in patients with *** In S

关键词： Diabetes mellitus Vaccine recommendation COVID-19 vaccine Influenza vaccine Pneumococcal vaccine Immunization Retrospective study

multi-Step Detection of Simplex and Duplex Wormhole Attacks over Wireless Sensor Networks

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Computers, materials & Continua 2022年第3期70卷 4241-4259页

作者： abrar m.Alajlan Self-Development Skills Department Common First Year DeanshipKing Saud UniversityRiyadhKSA

Detection of thewormhole attacks is a cumbersome process,particularly simplex and duplex over thewireless sensor networks(WSNs).Wormhole attacks are characterized as distributed passive attacks that can destabilize or disable *** distributed passive nature of these attacks makes them enormously challenging to *** main objective is to find all the possible ways in which how the wireless sensor network’s broadcasting character and transmission medium allows the attacker to interrupt network within the distributed *** further to detect the serious routing-disruption attack“Wormhole Attack”step by step through the different network *** this paper,a new multi-step detection(mSD)scheme is introduced that can effectively detect the wormhole attacks for *** mSD consists of three algorithms to detect and prevent the simplex and duplex wormhole ***,the proposed scheme integrated five detection modules to systematically detect,recover,and isolate wormhole *** results conducted inOmNET++show that the proposedmSDhas lower false detection and false toleration ***,mSDcan effectively detect wormhole attacks in a completely distributed network environment,as suggested by the simulation results.

关键词： Wireless sensor network wormhole attack node validation multi-step detection