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Tailoring the optical and magnetic properties of La-BaM hexaferrites by Ni substitution

Chinese Physics B 2022年第2期31卷 570-575页

作者： Hafiz T.ali MRamzan M Imran Arshad Nicola A.Morley M.hassan Abbas Mohammad Yusuf Atta Ur Rehman Khalid Mahmood Adnan ali Nasir Amin MAjaz-un-Nabi Department of Mechanical Engineering College of EngineeringTaif UniversityTaif 21944Saudi Arabia Department of Physics Government College UniversityFaisalabadPakistan Department of Materials Science and Engineering University of SheffieldSir Robert Hadfield BuildingMapping St.SheffieldS13JDUK Department of Clinical Pharmacy College of PharmacyTaif UniversityTaif 21944Saudi Arabia

We investigate the impact of Ni insertion on the structural,optical,and magnetic properties of Ba_(0.8)La_(0.2)Fe_(12-x)Ni_(x)O_(19)hexaferrites(Ni substituted La-BaM hexaferrites).Samples were prepared using the conventional co-precipitation method and sintered at 1000℃for 4 hours to assist the crystallization *** analysis of the structure of the samples was carried out using an x-ray diffraction(XRD)*** M-type hexagonal structure of all the samples was confirmed using XRD *** lattice parameters a and c were found to be in the ranges of 5.8925±0.001 nm–5.8952±0.001 nm and 23.2123±0.001 nm–23.2219±0.001 nm,*** M-type hexagonal nature of the prepared samples was also indicated by the presence of corresponding FT-IR bands and Raman modes in the FT-IR and Raman spectra,*** results confirmed the successful synthesis of the samples according to the required stoichiometric ratio.A UV-vis spectrometer was used to record the absorption spectra of the prepared samples in the wavelength range of 200 nm–1100 *** optical energy bandgap of the samples was found to be in the range of 1.21 eV–3.39 *** M–H loops of the samples were measured at room temperature at an applied magnetic field range of 0 kOe–60 kOe.A high saturation magnetization of 99.92 emu/g was recorded in the sample with x=0 at a microwave operating frequency of 22.2 *** high value of saturation magnetization is due to the substitution of La3+ions at the spin-up(12k,2a,and 2b)*** Ni substitution is proven to be a potential candidate for the tuning of the optical and magnetic parameters of M-type ***,we suggest that the prepared samples are suitable for use in magneto-optic applications.

关键词： M-type hexaferrite nanostructured materials magnetic properties optical properties

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An exploratory study on the use of enzyme activities as sediment tracers:biochemical fingerprints?

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International Journal of Sediment Research 2011年第2期26卷 136-151页

作者： Kazem NOSRATI Gerard GOVERS hassan AHMADI Forood SHARIFI Mohammad ali AMOOZEGAR Roel MERCKX Matthias VANMAERCKE Department of Physical Geography Faculty of Earth SciencesShahid Beheshti University Division of Geography Department of Earth and Environmental Sciences 3. Faculty ofNatural ResourcesUniversity of Tehran 4. ForestRange and Watershed Management Organization 5. Faculty of BiologyCollege of SciencesUniversity of Tehran 6. Division of Soil and Water ManagementDepartment of Earth and Environmental Sciences 7. Division of GeographyDepartment of Eaeth and Environmental Sciences

Little information exists on the potential of soil enzyme activities,which are sensitive to soil properties and management,for the characterization of sediment sources at the catchment *** objective of this study is to explore and evaluate enzyme activity as tracer for sediment fingerprinting in the Hiv catchment(55 km~2),***,four enzymes were measured from 42 different sampling sites,covering three sediment source areas(rangeland/surface erosion,orchard/surface erosion,and streambank erosion),as well as from 12 sediment samples from reservoir check dams (sediment sinks).The results indicate that,based upon backward mode discriminant analysis,βglucosidase and dehydrogenase,allowed more than 95%of the samples to be correctly assigned to their source *** enzymes were selected as input data for a mixing-model to determine the relative contribution of the sampled sediment *** mean contributions from rangeland, orchard and streambank sources in the study area were estimated as 11.3%,15.1%and 73.7%, *** geochemical tracers,the mean contribution from rangeland,orchard and streambank sources was estimated as 14.1%,9.5%and 74.8%,*** biochemical and geochemical tracers,similar values were obtained(18.7%,10.7%and 70.7%,respectively).Our results indicate that soil enzyme activity allows for a good characterization of sediment sources,and can provide a complementary tool to currently existing sediment fingerprinting ***, the method should be also tested in other regions.

关键词： Sediment source Enzyme activity Biochemical fingerprints Mixing model Hiv catchment

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Pediatric emergency preparedness in Canadian family physician offi ces:A national survey

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World Journal of Emergency Medicine 2021年第3期12卷 225-227页

作者： Dayae Jeong Subhrata Verma Anushka Weeraratne Marina Atalla Mohammed hassan-ali April J.Kam Department of Pediatrics University of TorontoToronto M5S 1A1Canada Department of Pediatrics University of WesternLondon N6A 3K7Canada Department of Pediatrics McMaster UniversityHamilton L8S 4K1Canada Department of Health Sciences McMaster UniversityHamilton L8S 4K1Canada Division of Pediatric Emergency Medicine McMaster UniversityHamilton L8S 4K1Canada

Dear editor,Family physicians often serve as the primary resource for parents seeking medical treatment for their children,and it is not uncommon for children with medical emergencies to be brought into primary care offices instead of local emergency departments(EDs).Although estimated incidence rates of pediatric emergencies in primary care offices vary based on the definition used,the number of patients seen,and clinic location,[1-3]any healthcare provider who sees pediatric patients should be ready for immediate medical intervention to minimize adverse outcomes.[4,5]Various studies in the USA have shown that outpatient offices are not adequately prepared for pediatric emergencies,whether that is defined as stocking recommended equipment,having policies for the transport of patients to EDs,engaging in mock codes,or being certified in Advanced Pediatric Life Support(APLS)or Basic Life Support(BLS).[1-3]This deficit in preparedness exists despite the presence of multiple nation-and state-wide guidelines on the subject,including a policy by the American Academy of Pediatrics.[3]Limited information exists on the preparedness of primary care physicians for pediatric emergencies in other nations.

关键词： physician Pediatric editor

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The impact of climatic variables on the population dynamics of the main malaria vector, Anopheles stephensi Liston(Diptera: Culicidae), in southern Iran

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Asian Pacific Journal of Tropical Medicine 2020年第10期13卷 448-455页

作者： Madineh Abbasi Abbas Rahimi Foroushani Tohid Jafari-Koshki Kamran Pakdad hassan Vatandoost Ahmad ali Hanafi-Bojd Deparment of Medical Entomology&Vector Control School of Public HealthTehran University of Medical SciencesTehranIran Infectious and Tropical Diseases Research Center Tabriz University of Medical SciencesTabrizIran Department of Epidemiology and Biostatistics School of Public HealthTehran University of Medical SciencesTehranIran Molecular Medicine Research Center Tabriz University of Medical SciencesTabrizIran Department of Statistics and Epidemiology Faculty of HealthTabriz University of Medical SciencesTabrizIran Department of Parasitology&Mycology Paramedical SchoolShahid Beheshti University of Medical SciencesTehranIran

Objective:To determine the significance of temperature,rainfall and humidity in the seasonal abundance of Anopheles stephensi in southern ***:Data on the monthly abundance of Anopheles stephensi larvae and adults were gathered from earlier studies conducted between 2002 and 2019 in malaria prone areas of southeastern *** data for the studied counties were obtained from climatology *** estimating equations method was used for cluster correlation of data for each study site in different ***:A significant relationship was found between monthly density of adult and larvae of Anopheles stephensi and precipitation,max temperature and mean temperature,both with simple and multiple generalized estimating equations analysis(P<0.05).But when analysis was done with one month lag,only relationship between monthly density of adults and larvae of Anopheles stephensi and max temperature was significant(P<0.05).Conclusions:This study provides a basis for developing multivariate time series models,which can be used to develop improved appropriate epidemic prediction systems for these ***-term entomological study in the studied sites by expert teams is recommended to compare the abundance of malaria vectors in the different areas and their association with climatic variables.

关键词： Anopheles stephensi Climatic variables Monthly activity Iran

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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 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

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Ultrastructural Identification of the Basal-Granulated Cells in the Duodenum of Albino Rat

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Open Journal of Gastroenterology 2014年第7期4卷 279-287页

作者： ali hassan A. ali Anatomy Department Salman Bin Abdulaziz University Al-Kharj KSA

The fine structure of the crypt epithelium of the duodenal mucosa in albino rats was studied to represent the types and distribution of the basal-granulated or endocrine cells. Twenty male animals were used. Perfusion-fixation was made and samples of duodenal mucosa were taken and processed to prepare epon-embedded specimens for examination by a transmission electron microscope. Cells containing membrane-bound granules were seen in the crypt epithelium. They were identified to be basal-granulated cells. Six different types of such cells were demonstrated. All of the cells were of the closed type. The possible functional significance of these closed cell types was discussed. Correlation among the distributions of such cells in the intestine of albino rat might enable the physiologists, internists and other research workers to study several biologically active peptides with well-established functions other than those which have long been investigated.

关键词： Basal Granulated Cells Neueroendocrine Cells Duodenum Albino Rats

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Hepatoprotective Effect of Green Tea Extract against Cyclophosphamide Induced Liver Injury in Albino Rats

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Forensic Medicine and Anatomy Research 2018年第2期6卷 11-19页

作者： ali hassan A. ali Anatomy Department College of Medicine Prince Sattam Bin Abdulaziz University Al-Kharj KSA Anatomy Department Faculty of Medicine Al-Azhar University Cairo Egypt

Background: Green tea intake is accompanied with a lower incidence of cardiovascular disease, cancer and neurodegenerative disorders;hence green tea extract has been included as dietary supplement along with other supplements and multivitamins. Aim of the Work: Studying the effect of cyclophosphamide administration on the liver of adult male albino rats and the possible protective role of green tea extract. Material and Methods: The current study was carried out on 45 adult male albino rats. They were divided into three equal groups (each included 15 rats). Group I (control group) was injected intraperitoneally with normal saline at a dosage of 0.5 mg/kg body weight twice weekly for 9 weeks. Group II was injected intraperitoneally with cyclophosphamide (CP) (150 mg/kg/day) for two weeks. Group III: rats received green tea extracts orally (50 mg/kg/day) for three weeks, and then continued for further two weeks concomitantly with intraperitoneally cyclophosphamide (CP) injected (150 mg/kg/day). Results: Rats exposed to cyclophosphamide (CP) showed several histological and histochemical changes in their liver. These changes were improved by using green tea. Conclusion: The present work showed that green tea had preventive and therapeutic effect upon livers of albino rats after they were exposed to CP.

关键词： Green Tea Albino Rats Liver Cyclophosphamide

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Integrated Fault Diagnosis Model Using Tiny Residual Network

Integrated Fault Diagnosis Model Using Tiny Residual Network

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作者： Sa’ad Abdo-Alkawi ali hassan Almageedy（青山）华南理工大学

学位级别：硕士

随着制造业的快速发展,使得相关企业对机械设备安全防护系统的需求在不断提高。同时,机械设备的智能故障诊断技术是迈向智能制造的关键过程,也是未来工业发展的趋势。然而,由于现有故障诊断技术的不足,导致需要耗费较大的人工成本来协... 详细信息

随着制造业的快速发展,使得相关企业对机械设备安全防护系统的需求在不断提高。同时,机械设备的智能故障诊断技术是迈向智能制造的关键过程,也是未来工业发展的趋势。然而,由于现有故障诊断技术的不足,导致需要耗费较大的人工成本来协助完成机械设备故障的监测和诊断。针对该问题,深度学习时代的来临让机械设备故障诊断领域步入了迅速发展的轨道,并且引起了学术界和工业界的广泛关注。传统的故障诊断方法需要经过特征提取、特征选择和特征分类的过程,处理过程繁杂并且实际的应用成本高。另外,传统故障诊断方法可能还需要依靠相关领域专业知识的协助和分析,否则将会导致最终诊断结果的不确定性较大。因此,本文基于深度学习技术的思想,结合微小残差网络、时频分析方法和特定的激活函数等技术,提出了一种新的机械故障诊断模型。本文的主要工作内容如下:1.针对传统方法故障诊断过程繁杂并且识别准确率不确定性较大等问题,本文提出了一种基于残差网络的深度卷积神经网络故障诊断模型,简称ITResNet。ITResNet模型采用基于残差网络的设计能够有效克服梯度消失的问题,并且能够直接采用原始故障数据对模型进行训练,从而达到自动识别机械设备故障的目的。2.针对ITResNet模型难以处理原始故障数据噪声污染严重的问题,本文提出采用三种不同的时频分析方法对原始故障进行预处理。时频分析方法能够将原始的一维故障数据通过时频转换,可以转变为二维故障数据。通过结合时频分析技术对ITResNet模型的训练过程进行改进,有效提高了模型对机械故障数据的学习和分类能力。通过实验表明,改进后的ITResNet模型对正常状态和故障状态的数据区分能力更强。3.针对ITResNet模型的分类拟合能力难以达到理想状态的问题,本文基于新的Mish激活函数、Nadam优化器技术和空间金字塔池以及压缩激励结构对ITResNet模型进行了进一步改进,简称ITResNet-SPP-SE。结合这些技术进行改进后,能够有效减少模型的参数数量。通过实验表明,ITResNet-SPP-SE模型的故障分类准确率和稳定性要优于ITResNet模型,并且运行耗时更低。采用轴承故障数据集对本文提出的模型进行了验证和分析。实验结果表明,本文提出的ITResNet模型、采用时频分析方法改进的ITResNet模型和ITRees Net-SPP-SE模型在故障分类准确率方面,分别达到了99.8%,99.99%和99.999%。并且ITRees Net-SPPSE模型的拟合能力比ITResNet模型和改进的ITResNet模型更强。另外,在采用其它方法模型的对比实验方面,传统方法例如SVM、KNN和MLP的预测准确率分别为71%,33%,87%;基于深度学习技术的方法,例如深度完全卷积神经网络（DFCNN）,堆叠降噪自动编码器（SDAE）和自适应卷积神经网络,它们对特定类型的信号进行操作,其准确度分别为99.22%,91.79%和97.90%。因此,可以看出我们提出的集成模型在机械故障分类预测方面表现的更好。

关键词：智能故障诊断卷积神经网络残差网络深度学习旋转机械

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Use of Random Amplified Polymorphic DNA Analysis for Economically Important Food Crops

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Journal of Integrative Plant Biology 2007年第12期49卷 1670-1680页

作者： Halima hassan Salem Bahy Ahmed ali Tian-Hua Huang Da-Nian Qin Xiao-Mei Wang Qing-Dong Xie Cell Biology and Medical Genetics Department Medical College Shantou University Shantou 515031 Nucleic Acid Research Department Genetic Engineering and Biotechnology Research InstituteMubarak City for Scientific Research & Technology Applications New Borg El-Arab City 21934 Alexandria Egypt Physiology Department Medical College Shantou University Shantou 515031 China Department of Biochemistry and Molecular Biology Life Science School Shenzhen University Shenzhen 518060 China

The objective of this review is to summarize numerous studies on the use of the random amplified polymorphic DNA （RAPD） technique on rice, corn, wheat, sorghum, barley, rye, and oats to examine its feasibility and validity for assessment of genetic variation, population genetics, mapping, linkage and marker assisted selection, phylogenetic analysis, and the detection of somaclonal variation. Also we discuss the advantages and limitations of RAPD. Molecular markers have entered the scene of genetic improvement in different fields of agricultural research. The simplicity of the RAPD technique made it ideal for genetic mapping, plant and animal breeding programs, and DNA fingerprinting, with particular utility in the field of population genetics.

关键词： random amplified polymorphic DNA food crops poaceae.

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Design of a Compact Monopole Antenna for UWB Applications

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Computers, Materials & Continua 2021年第1期66卷 35-44页

作者： Naeem Ahmad Jan Saad hassan Kiani Daniyal ali Sehrai Muhammad Rizwan Anjum Amjad Iqbal Mujeeb Abdullah Sunghwan Kim Department of Electrical Engineering Iqra National UniversityPeshawar25000Pakistan Department of Electrical Engineering City University of Science and Information TechnologyPeshawar25000Pakistan Department of Electronic Engineering The Islamia University of BahawalpurBahawalpur63100Pakistan Department of Electrical Engineering Multimedia UniversityCyberjaya63100Malaysia Department of Computer Science Bacha Khan UniversityCharsadda24420Pakistan School of Electrical Engineering University of UlsanUlsan44610Korea

In this paper,a low cost,highly efficient and low profile monopole antenna for ultra-wideband(UWB)applications is presented.A new inverted triangular-shape structure possessing meander lines is designed to achieve a wideband response and high *** design the proposed structure,three steps are utilized to achieve an UWB *** bandwidth of the proposed antenna is improved with changing meander lines parameters,miniaturization of the ground width and optimization of the feeding *** measured and simulated frequency band ranges from 3.2 to 12 GHz,while the radiation patterns are measured at 4,5.3,6 and 8 GHz frequency *** overall volume of the proposed antenna is 26×25×1.6 mm^(3);whereas the FR4 material is used as a substrate with a relative permittivity and loss tangent of 4.3 and 0.025,*** peak gain of 4 dB is achieved with a radiation efficiency of 80 to 98%for the entire *** modelling of proposed antenna is performed in ANSYS HFSS 13 software.A decent consistency between the simulated and measured results is accomplished which shows that the proposed antenna is a potential candidate for the UWB applications.

关键词： Ultra-wideband(UWB) meander lines monopole antenna high efficiency high gain ANSYS HFSS

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