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作者： WDAAN RAMI nasser SALEH 吉林大学

学位级别：硕士

背景:松果体是位于间脑顶部,缰连合与后连合之间的红色小体,像松果一样的形状,是一个微小但功能强大的结构。它的颜色是红灰色,直径为5-8毫米。松果体属于内分泌或神经内分泌腺,对身体的稳态系统有重要影响,在各种身体功能中起着重要的... 详细信息

背景:松果体是位于间脑顶部,缰连合与后连合之间的红色小体,像松果一样的形状,是一个微小但功能强大的结构。它的颜色是红灰色,直径为5-8毫米。松果体属于内分泌或神经内分泌腺,对身体的稳态系统有重要影响,在各种身体功能中起着重要的作用。它负责产生褪黑素,控制包括生物钟、睡眠-觉醒周期、温度调节和免疫系统在内的各种生理过程。褪黑素还可以影响月经和生殖系统,并与肿瘤抑制有关。随着时间的推移,松果体会出现生理性钙化,但这种现象在一小部分儿童中也被观察到(8岁以下的儿童中有2%,青少年中有10%),到30岁时,大多数人的松果体均已出现钙化。脉络丛是由软脑膜及其上的血管与室管膜上皮共同构成的脉络组织,位于中枢神经系统的脑室内,是脑部另一个关键结构。在产生脑脊液中起着关键作用,每天产生约600毫升的液体。它在胎儿生长的第20周完成发育,室管膜细胞,它们覆盖在脑室上,形成了围绕脉络丛的连续层。到15岁时,大约5%的儿童和40岁的大多数成人观察到脉络丛的钙化。这些钙化通常可以在侧脑室、第三脑室、第四脑室、Luschka孔、Magendie孔和脉络膜裂中观察到。颅内钙化是指在脑组织内的血管壁上发生的钙沉积。虽然在某些区域的正常钙化通常无症状,但根据钙化的位置和程度,异常钙化的出现可能会导致临床症状的发生。生理性颅内钙化,如松果体和脉络丛钙化,更常见于老年人,通常不导致临床症状。然而,其他区域如血管或脑实质的钙化往往与一些临床症状相关,如帕金森病、痴呆、精神病和情绪障碍。随着现在医疗技术的不断发展,多种医疗技术不断出现并应用于临床,医疗工作人员可以通过如X线、计算机断层扫描(computed tomography,CT)、磁共振成像(Magnetic resonance imaging,MRI)和超声等多种手段来检测和诊断颅内钙化。其中,CT因其对钙化的识别更敏感,在颅内钙化的诊断中应用广泛。目的:本研究旨在利用CT扫描技术调查也门人群中松果体和脉络丛的钙化情况。比较也门不同年龄组和性别之间松果体和脉络丛的钙化率,找出松果体和脉络丛钙化大小的标准值,以及使用Hounsfield(HU)单位测量松果体和脉络丛钙化的密度,并探讨松果体和脉络丛钙化是否与某些疾病(如肾病、阿尔茨海默病、精神分裂症、糖尿病、睡眠障碍、心血管疾病、痴呆和高血压)的发展存在关联,研究这种生理钙化与疾病之间的关系。方法:本研究纳入了2021年7月至2021年12月期间在也门萨那市的政府医院和放射诊断中心的放射科使用飞利浦CT扫描仪进行脑部CT扫描的所有患者。共收集了300例病例并纳入研究,年龄1～90岁,分为1-10岁、11-20岁、21-30岁、31-40岁、41-50岁、51-60岁和60岁以上七个年龄段。通过Radi Ant DICOM查看器4.6.9程序对收集的入组人群数据进行松果体和脉络丛钙化的长度和宽度测量,并测量钙化的放射密度值(HU)。采用结构化问卷收集患者的现病史及既往史,问卷从患者处收集,年龄较小的患者信息从父母那里获取,问卷包括:肾脏疾病,阿尔茨海默氏症,精神分裂症,糖尿病,睡眠障碍,心血管疾病,痴呆症和高血压。并使用SPSS 21.0版本和Microsoft Excel 2013软件对数据进行分析。采用描述性统计,如频率和百分比,来描述样本特征。数据以表格、饼图和条形图的形式呈现。使用Pearson相关分析来确定松果体及脉络丛钙化与疾病之间的相关性。统计显著性的临界点设定为P<0.05。本研究共纳入样本300例,包括不同年龄组,将其分为1-10岁、11-20岁、21-30岁、31-40岁、41-50岁、51-60岁和60岁以上七个年龄段,其中分布最多的年龄组是1-10岁(21.0%)和60岁以上(20.3%)。从性别分布来看,男性161人(53.7%),女性139人(46.3%)。结果:对所有参与者的CT检查分析后发现,205名参与者(68.3%)存在松果体钙化,197名参与者(65.7%)有脉络丛钙化。对于脉络丛钙化而言,6名参与者(3.0%)出现右侧脉络膜丛钙化,13名参与者(6.6%)出现左侧脉络膜丛钙化,178名参与者(90.4%)出现双侧脉络膜丛钙化。松果体钙化发生率最高的是60岁以上年龄组,包括54名参与者(18.0%),发生率最低的是1-10岁年龄组,包括3名参与者(1.0%)。脉络丛钙化发生率最高的是60岁以上年龄组,包括57名参与者(19.0%)。发生率最低的是1-10岁年龄组,包括8名参与者(2.7%)。我们发现松果体和脉络丛钙化在老年人群中发生率最高,随着年龄的增长,生理性颅内钙化越来越普遍。松果体和脉络膜丛的钙化是一个随着年龄的增长而发生的自然过程,钙盐在组织中积累,形成坚硬的矿化结构,这一过程被认为与随着

关键词：松果体脉络丛钙化 CT

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Refraction characteristics of phononic crystals

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Acta Mechanica Sinica 2015年第4期31卷 481-493页

作者： Sia Nemat-nasser Department of Mechanical and Aerospace Engineering University of California

Some of the most interesting refraction prop- erties of phononic crystals are revealed by examining the anti-plane shear waves in doubly periodic elastic composites with unit cells containing rectangular and/or elliptical multi- inclusions. The corresponding band structure, group velocity, and energy-flux vector are calculated using a powerful mixed variational method that accurately and efficiently yields all the field quantities over multiple frequency pass-bands. The background matrix and the inclusions can be anisotropic, each having distinct elastic moduli and mass densities. Equifrequency contours and energy-flux vectors are read- ily calculated as functions of the wave-vector components. By superimposing the energy-flux vectors on equifrequency contours in the plane of the wave-vector components, and supplementing this with a three-dimensional graph of the corresponding frequency surface, a wealth of information is extracted essentially at a glance. This way it is shown that a composite with even a simple square unit cell con- taining a central circular inclusion can display negative or positive energy and phase velocity refractions, or simply performs a harmonic vibration （standing wave）, depending on the frequency and the wave-vector. Moreover, that the same composite when interfaced with a suitable homoge- neous solid can display：（1） negative refraction with negative phase velocity refraction; （2） negative refraction with pos- itive phase velocity refraction; （3） positive refraction with negative phase velocity refraction; （4） positive refraction with positive phase velocity refraction; or even （5） completereflection with no energy transmission, depending on the fre- quency, and direction and the wavelength of the plane-wave that is incident from the homogeneous solid to the interface. For elliptical and rectangular inclusion geometries, analyti- cal expressions are given for the key calculation quantities. Expressions for displacement, velocity, linear m

关键词： Doubly periodic composites - Phononiccrystals Band structure Group and energy-flux vectors

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Multichannel imaging for monitoring chemical composition and germination capacity of cowpea(Vigna unguiculata) seeds during development and maturation

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The Crop Journal 2022年第5期10卷 1399-1411页

作者： Gamal ElMasry nasser Mandour Yahya Ejeez Didier Demilly Salim Al-Rejaie Jerome Verdier Etienne Belin David Rousseau Agricultural Engineering Department Faculty of AgricultureSuez Canal UniversityIsmailiaEgypt Groupe d’Etude et de Controle des Variétés et des Semences(GEVES) Station Nationale d’Essais de Semences(SNES)Beaucouze49071AngersFrance Department of Pharmacology&Toxicology College of PharmacyKing Saud UniversitySaudi Arabia Laboratoire Angevin de Recherche en Ingenierie des Systemes(LARIS) Universited’AngersAngersFrance Institut National de la Recherche Agronomique(INRA) UMR1345 Institut de Recherche en Horticulture et SemencesBeaucouzéF-49071AngersFrance

This study aimed to set a computer-integrated multichannel spectral imaging system as a high-throughput phenotyping tool for the analysis of individual cowpea seeds harvested at different developmental stages. The changes in germination capacity and variations in moisture, protein and different sugars during twelve stages of seed development from 10 to 32 days after anthesis were nondestructively monitored. Multispectral data at 20 discrete wavelengths in the ultraviolet, visible and near infrared regions were extracted from individual seeds and then modelled using partial least squares regression and linear discriminant analysis(LDA) models. The developed multivariate models were accurate enough for monitoring all possible changes occurred in moisture, protein and sugar contents with coefficients of determination in prediction R^(2) of 0.93, 0.80 and 0.78 and root mean square errors in prediction(RMSEP) of 6.045%, 2.236% and 0.890%, respectively. The accuracy of PLS models in predicting individual sugars such as verbascose and stachyose was reasonable with R~2 of 0.87 and 0.87 and RMSEP of 0.071%and 0.485%, respectively;but for the prediction of sucrose and raffinose the accuracy was relatively limited with R^(2) of 0.24 and 0.66 and RMSEP of 0.567% and 0.045%, respectively. The developed LDA model was robust in classifying the seeds based on their germination capacity with overall correct classification of96.33% and 95.67% in the training and validation datasets, respectively. With these levels of accuracy,the proposed multichannel spectral imaging system designed for single seeds could be an effective choice as a rapid screening and non-destructive technique for identifying the ideal harvesting time of cowpea seeds based on their chemical composition and germination capacity. Moreover, the development of chemical images of the major constituents along with classification images confirmed the usefulness of the proposed technique as a non-destructive tool for estim

关键词： Multispectral imaging Multichannel imaging Chemical imaging Spectral analysis Seeds Cowpea

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A Survey on Acute Leukemia Expression Data Classification Using Ensembles

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Computer Systems Science & Engineering 2023年第11期47卷 1349-1364页

作者： Abdel nasser H.Zaied Ehab Rushdy Mona Gamal Department of Information Systems Faculty of Computer ScienceMisr International UniversityCairo11828Egypt Department of Information Technology Faculty of Computers and InformaticsZagazig UniversityZagazig44516Egypt Department of Information Systems Faculty of Computers and InformaticsZagazig UniversityZagazig44516Egypt

Acute leukemia is an aggressive disease that has high mortality rates *** error rate can be as high as 40%when classifying acute leukemia into its ***,there is an urgent need to support hematologists during the classification *** than two decades ago,researchers used microarray gene expression data to classify cancer and adopted acute leukemia as a test *** high classification accuracy they achieved confirmed that it is possible to classify cancer subtypes using microarray gene expression *** machine learning is an effective method that combines individual classifiers to classify new *** classifiers are recognized as powerful algorithms with numerous advantages over traditional *** the past few decades,researchers have focused a great deal of attention on ensemble classifiers in a wide variety of fields,including but not limited to disease diagnosis,finance,bioinformatics,healthcare,manufacturing,and *** paper reviews the recent ensemble classifier approaches utilized for acute leukemia gene expression data ***,a framework for classifying acute leukemia gene expression data is *** pairwise correlation gene selection method and the Rotation Forest of Bayesian Networks are both used in this *** outcomes show that the classification accuracy achieved by the acute leukemia ensemble classifiers constructed according to the suggested framework is good compared to the classification accuracy achieved in other studies.

关键词： Leukemia classification ensemble rotation forest pairwise correlation bayesian networks gene expression data microarray gene selection

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Antibacterial activity and mechanism of newly developed Zr-30Ta and Zr-25Ta-5Ti alloys against implant-associated infection

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Rare Metals 2022年第12期41卷 4176-4187页

作者： Hai-Lin Yang Akram nasser Juaim Ling Zou Meng-Zhen Zhu Xiao-Na Chen Chen-Xu Ma Xiong-Wen Zhou State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha 410008China Department of Prosthodontics Center of StomatologyXiangya HospitalCentral South UniversityChangsha 410008China Department of Prosthodontics Faculty of DentistryThamar UniversityDharmarYemen Department of Oral Implantology Xiangya Stomatological Hospital and School of StomatologyCentral South UniversityChangsha 410008China

Infection is a common problem after implantation,and the currently used Ti-based implants have insufficient antibacterial *** newly developed Zr-30Ta and Zr-25Ta-5Ti alloys exhibited good mechanical properties,low elastic moduli,and high corrosion *** this work,their antibacterial activities and antibacterial mechanisms were *** surface roughness,wettability,and charge of the alloys were evaluated using a profilometer,drop shape analyzer,and electrokinetic analyzer,*** antibacterial activity against Streptococcus mutans and Porphyromonas gingivalis was investigated using the inhibition zone assay,plate count assay,live/dead staining,and scanning electron microscopy(SEM).The reactive oxygen species release(ROS)was evaluated using the 2’7’-dichlorodihydrofluorescein diacetate(DCFH-DA)*** results demonstrated that Zr-30Ta and Zr-25Ta-5Ti alloys had favorable smooth,hydrophilic,negatively charged surfaces that decreased bacteria adhesion and prevented biofilm ***-30Ta and Zr-25Ta-5Ti alloys also exhibited a time-dependent decrease in the bacteria adhesion and ***-30Ta and Zr-25Ta-5Ti alloys were also found to induce direct membrane damage and increase ROS production,resulting in significantly better antibacterial activities than ***-30Ta and Zr-25Ta-5Ti alloys exhibited comparable antibacterial *** work suggests that the newly developed Zr-30Ta and Zr-25Ta-5Ti alloys have good antibacterial activity against Streptococcus mutans and Porphyromonas gingivalis and are promising candidate materials for dental and orthopedic implants.

关键词： Zirconium-tantalum Dental implant Antibacterial Peri-implant infection Biofilm

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Dynamic trip point categorisation using manufacturing process for polycrystalline diamond compact bits as case study

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Journal of Control and Decision 2022年第3期9卷 311-321页

作者： Zubair Ahmad Khan Khalid Khan Shuja Ahmad Khan Shahbaz Khan Muhammad Tufail Abdel nasser Mechatronics Department University of Engineering and Technology PeshawarPeshawarPakistan Materials for Energy Storage and Conversion US Pakistan Centre for Advanced Studies in Energy University of Engineering and Technology PeshawarPeshawarPakistan Bakar Hughes HoustonGermany Jacobs DallasTXUSA

Disruptions in the manufacturing process cast substantial impacts on the consumer’s centric values,cost,and overall *** ripple effect of these disruptions is observed in the whole assembly *** proper analysis and mitigation of disruptions is the key to the proficiency of the plant and resource *** research focuses on the quantitative analysis of the impact of disruptions of the manufacturing process,which is performed by analysing the disruptive workstation *** disruptive workstations have a significant impact on succeeding and preceding workstations,which have been analysed dynamically,and accordingly,the preset alarm trip points are *** results show that lowering the number of starts and stops decreases the number of rejections of valuable process batches that finally improve ***,the developed model is implemented on a polycrystalline diamond compact drill bit manufacturing *** results are compared with the research work of other researchers,showing a 60%reduction in the number of start/stop events,60%reduction in downtime,while a 75%reduction in the number of rejections is noted.

关键词： Disruptions dynamic assessment downtime alarm tripoints

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The etiological spectrum of bowel obstruction and early postoperative outcome among neonates at a tertiary hospital in Uganda

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World Journal of Pediatric Surgery 2022年第4期5卷 247-254页

作者： Paul Otim Emmanuel Alex Elobu Ronald Mbiine nasser Kakembo David Komakech Surgery Saint Mary's Hospital LacorGuluUganda Surgery Makerere UniversityKampalaUganda Surgery Mbarara University of Science and TechnologyMbararaUgandaUganda

Background Bowel obstruction is a common surgical emergency in ***-fourth of neonates with obstruction suffer postoperative complications,with high mortality,especially in low-income *** attributed to mortality include prematurity,late presentation and associated multiple congenital *** prevalence and the predictors of mortality in our setting have not been well *** aimed to describe the early postoperative outcomes and to determine the predictors of mortality among neonates with bowel *** We conducted a prospective cohort study during 4 months,when we recruited postoperative neonates from the pediatric surgery unit of Mulago *** collected data on demographics,clinical presentations,maternal characteristics,the surgical procedure performed,postoperative outcomes,*** follow-up for 2 weeks,we analyzed the data using Cox proportional hazards regression models of predictors of *** A total of 76 neonates were recruited,with a male-to-female ratio of 2.2:*** age ranged from 1 to 26 days,a median of 3[interquartile range(IQR):2,7].About 67.1%had birth weights ranging between 2.5 kg and 3.5 kg,a mean of 2.8[standard deviation(SD)=0.64];76.3%were termed;with anorectal malformation(ARM),31.6%as the leading cause,followed by jejunoileal atresia(JIA),25%.Nearly 55.3%of neonates developed complications;53.9%with post-operative fever,15.8%had wound *** mortality rate was 44.7%(34/76)and was highest among cases of JIA,41.2%.The predictors of mortality included prematurity,fever at admission,breastfeeding status,and mother’s parity as well as the cadre of healthcare providers(p<0.005).Conclusions ARM is the predominant cause of bowel obstruction among neonates,followed by *** morbidity and mortality due to bowel obstruction among neonates are unacceptably *** major predictors of mortality were prematurity,fever at admission,and the cadre of the healthcare providers.

关键词： postoperative mother nates

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Delay-Constrained Optimized Packet Aggregation in High-Speed Wireless Networks

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Journal of Computer Science & Technology 2013年第3期28卷 525-539页

作者： Peyman Teymoori nasser Yazdani School of Electrical and Computer Engineering University College of Engineering University of Tehran School of Computer Science Institute for Research in Fundamental Sciences

High-speed wireless networks such as IEEE 802.11n have been introduced based on IEEE 802.11 to meet the growing demand for high-throughput and multimedia applications. It is known that the medium access control （MAC） efficiency of IEEE 802.11 decreases with increasing the physical rate. To improve efficiency, few solutions have been proposed such as Aggregation to concatenate a number of packets into a larger frame and send it at once to reduce the protocol overhead. Since transmitting larger frames eventuates to dramatic delay and jitter increase in other nodes, bounding the maxi- mum aggregated frame size is important to satisfy delay requirements of especially multimedia applications. In this paper, we propose a scheme called Optimized Packet Aggregation （OPA） which models the network by constrained convex optimization to obtain the optimal aggregation size of each node regarding to delay constraints of other nodes. OPA attains proportionally fair sharing of the channel while satisfying delay constrains. Furthermore, reaching the optimal point is guaranteed in OPA with low complexity. Simulation results show that OPA can successfully bound delay and meet the requirements of nodes with only an insignificant throughput penalty due to limiting the aggregation size even in dynamic conditions.

关键词： high-speed wireless network delay requirement aggregation convex optimization

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Drift DetectionMethod Using DistanceMeasures and Windowing Schemes for Sentiment Classification

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Computers, Materials & Continua 2023年第3期74卷 6001-6017页

作者： Idris Rabiu Naomie Salim Maged nasser Aminu Da’u Taiseer Abdalla Elfadil Eisa Mhassen Elnour Elneel Dalam School of Computing Univerti Teknologi MalaysiaJohor81310Malaysia UTM Big Data Centre Ibnu Sina Institute for Scientific and Industrial ResearchUniversiti Teknologi MalaysiaJohor81310Malaysia Ibrahim Badamasi Babangida University LapaiPMB 11Niger SteateNigeria UNITAR Graduate School UNITAR International UniversityTierra CrestJln SS6//3Petaling Jaya47301SelangorMalaysia Department of Information Systems-Girls Section King Khalid UniversityMahayil62529Saudi Arabia Department of Mathematics-Girls Section King Khalid UniversityMahayil62529Saudi Arabia

Textual data streams have been extensively used in practical applications where consumers of online products have expressed their views regarding online *** to changes in data distribution,commonly referred to as concept drift,mining this data stream is a challenging problem for *** majority of the existing drift detection techniques are based on classification errors,which have higher probabilities of false-positive or missed *** improve classification accuracy,there is a need to develop more intuitive detection techniques that can identify a great number of drifts in the data *** paper presents an adaptive unsupervised learning technique,an ensemble classifier based on drift detection for opinion mining and sentiment *** improve classification performance,this approach uses four different dissimilarity measures to determine the degree of concept drifts in the data *** a drift is detected,the proposed method builds and adds a new classifier to the *** add a new classifier,the total number of classifiers in the ensemble is first checked if the limit is exceeded before the classifier with the least weight is removed from the *** this end,a weighting mechanism is used to calculate the weight of each classifier,which decides the contribution of each classifier in the final classification *** experiments were conducted on real-world datasets and the resultswere evaluated on the false positive rate,miss detection rate,and accuracy *** proposed method is also compared with the state-of-the-art methods,which include DDM,EDDM,and PageHinkley with support vector machine(SVM)and Naive Bayes classifiers that are frequently used in concept drift detection *** all cases,the results show the efficiency of our proposed method.

关键词： Data streams sentiment analysis concept drift ensemble classification adaptive window

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Boosting Effective Cooperation Morocco and China look to realising their enormous cooperation potential through the creation of an efficient Sino-African cooperation model

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ChinAfrica 2023年第11期15卷 30-31页

作者： nasser BOUCHIBA Africa-China Cooperation Association for Development

Morocco and China are marking the 65th anniversary of their diplomatic ties this *** have had diplomatic ties since November 1958,and their relationship has progressed steadily and fairly ever *** have seen the beginning of a notable process of cooperation in the political,economic,commercial,and cultural spheres during this time,accumulating fruitful results in many areas,we have also seen the enduring friendship between two peoples who are the descendants of ancient civilisations that are deeply rooted in the history of humanity.

关键词： cooperation creation enormous

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