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Type Ⅰ kerogen-rich oil shale from the Democratic Republic of the Congo: mineralogical description and pyrolysis kinetics

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Petroleum Science 2020年第1期17卷 255-267页

作者： rajaa bouamoud Ely Cheikh Moine Raphaèl Mulongo-Masamba Adnane El Hamidi Mohammed Halim Said Arsalane Laboratory of Nanomaterials Nanotechnologies and EnvironmentCenter of Science of MaterialsFaculty of SciencesMohammed V University in RabatAvenue Ibn BattoutaBP:101410000 RabatMorocco Research Unit of Materials Chemistry Faculty of Science and TechnologyUNANouakchottMauritania Department of Geochemistry Center for Geological and Mining Research(CGMR)KinshasaDemocratic Republic of the Congo

The Democratic Republic of the Congo holds important reserves of oil shale which is still under geological ***,the characterization and pyrolysis kinetics of typeⅠkerogen-rich oil shale of the western Central Kongo(CK)were investigated.X-ray diffraction,Fourier-transform infrared spectroscopy and thermal analysis(TG/DTA)showed that CK oil shale exhibits a siliceous mineral matrix with a consistent organic matter rich in aliphatic *** pyrolysis behavior of kerogen revealed the presence of a single mass loss between 300 and 550°C,estimated at 12.5%and attributed to the oil production ***-isothermal kinetics was performed by determining the activation energy using the iterative isoconversional model-free methods and exhibits a constant value with E=211.5±4.7 kJ *** most probable kinetic model describing the kerogen pyrolysis mechanism was obtained using the Coats–Redfern and Arrhenius plot *** results showed a unique kinetic triplet confirming the nature of kerogen,predominantly typeⅠand reinforcing the previously reported geochemical characteristics of the CK oil ***,the calculation of thermodynamic parameters(ΔH~*,ΔS~*andΔG~*)corresponding to the pyrolysis of typeⅠkerogen revealed that the process is non-spontaneous,in agreement with DTA experiments.

关键词： TypeⅠkerogen Pyrolysis kinetics Isoconversional methods Mineralogy Central Kongo oil shale

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Obstetric Anesthesia Practice Significantly Evolved: A Field for Cesarean Delivery Parturient for the Provision of Safe Anesthesia in Urgent Circumstances

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Open Journal of Anesthesiology 2024年第3期14卷 66-92页

作者： Mustafa Zakaria Amal Haoudar Said Makani Mariame Kabbour Oumaima Taoussi Karim Elaidaoui Yousra rajaa Chafik El Kettani Adil Elghanmi Department of Anesthesia and Resuscitation Hospital ZNA Middelheim Antwerpen Belgium European Society of Anaesthesiology and Intensive Care Ghent Belgium Anesthesia and Resuscitation Services Mohammed VI University of Sciences and Health-UM6SS Casablanca Morocco Cardiologist Vascular Surgery Mohammed VI University of Sciences and Health-UM6SS Casablanca Morocco Faculty of Science and Technology Hassan II University of Casablanca Casablanca Morocco Departement of Services Cardiology Mohammed VI University of Sciences and Health-UM6SS Casablanca Morocco Department of Anesthesia and Resuscitation Mohammed VI University of Sciences and Health-UM6SS Casablanca Morocco Obstetrics and Gynecology Services Mohammed VI University of Sciences and Health-UM6SS Casablanca Morocco

General anesthesia and Obstetric Anesthesia is the gold standard for a cesarean section but there are some cases where general anesthesia is unavoidable. The use of general anesthesia for cesarean delivery has decreased in recent years due to the widespread use of neuraxial techniques. The choice of anesthesia techniques for cesarean delivery depends on several factors, including the patient’s psychology and the attending physician’s experience. It is chosen because of its safety profile and its benefits to the mother and fetus. It may be indicated due to emergency, maternal refusal of regional techniques, or regional contraindications. Major complications include failed intubation, gastric content aspiration, and increased bleeding risk. This study aims to evaluate the impact of a newly launched team on obstetric anesthesia practice.

关键词： General Anesthesia Cesarean Delivery Intubation Maternal Refusal Obstetric Anesthetists

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Neutron-gamma discrimination method based on blind source separation and machine learning

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Nuclear Science and Techniques 2021年第2期32卷 70-80页

作者： Hanan Arahmane El-Mehdi Hamzaoui Yann Ben Maissa rajaa Cherkaoui El Moursli Universite´Paris-Saclay CEAList91120 PalaiseauFrance Equipe des Sciences de la Matie`re et du Rayonnement(ESMaR) Faculty of SciencesMohammed V University in RabatB.P.1014 RPRabatMorocco National Centre for Nuclear Energy Science and Technology(CNESTEN)B.P.1382 R.P.10001RabatMorocco Laboratory of Telecommunications Networks and Service SystemsNational Institute of Posts and TelecommunicationsAllal El Fassi AvenueRabatMorocco

The discrimination of neutrons from gamma rays in a mixed radiation field is crucial in neutron detection *** approaches have been proposed to enhance the performance and accuracy of neutron-gamma ***,their performances are often associated with certain factors,such as experimental requirements and resulting mixed *** main purpose of this study is to achieve fast and accurate neutron-gamma discrimination without a priori information on the signal to be analyzed,as well as the experimental ***,a novel method is proposed based on two *** first method exploits the power of nonnegative tensor factorization(NTF)as a blind source separation method to extract the original components from the mixture signals recorded at the output of the stilbene scintillator *** second one is based on the principles of support vector machine(SVM)to identify and discriminate these *** addition to these two main methods,we adopted the Mexican-hat function as a continuous wavelet transform to characterize the components extracted using the NTF *** resulting scalograms are processed as colored images,which are segmented into two distinct classes using the Otsu thresholding method to extract the features of interest of the neutrons and gamma-ray components from the background *** subsequently used principal component analysis to select the most significant of these features wich are used in the training and testing datasets for ***-variance analysis is used to optimize the SVM model by finding the optimal level of model complexity with the highest possible generalization *** this framework,the obtained results have verified a suitable bias–variance trade-off *** achieved an operational SVM prediction model for neutron-gamma classification with a high true-positive *** accuracy and performance of the SVM based on the NTF was evaluated and validated by comparing it to the charge comparison

关键词： Blind source separation Nonnegative tensor factorization(NTF) Support vector machines(SVM) Continuous wavelets transform(CWT) Otsu thresholding method

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Genetic polymorphism in Leishmania infantum isolates from human and animals determined by nagt PCR-RFLP

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Infectious Diseases of Poverty 2018年第1期7卷 523-530页

作者： Adil El Hamouchi Sofia El Kacem rajaa Ejghal Meryem Lemrani Laboratory of Parasitology and Vector-Borne-Diseases Institut Pasteur du MarocCasablancaMorocco

Background:Leishmania infantum is the causative agent of human visceral leishmaniasis(VL)and sporadic human cutaneous leishmaniasis(CL)in the Mediterranean *** genetic variation of the Leishmania parasites may result in different phenotypes that can be associated with the geographical distribution and diversity of the clinical *** main objective of this study was to explore the genetic polymorphism in *** isolates from human and animal hosts in different regions of ***:The intraspecific genetic variability of 40 Moroccan *** MON-1 strains isolated from patients with VL(n=31)and CL(n=2)and from dogs(n=7)was evaluated by PCR-RFLP of nagt,a single-copy gene encoding N-acetylglucosamine-1-phosphate *** a more complete analysis of *** polymorphism,we included the restriction patterns of nagt from 17 strains available in the literature and patterns determined by in-silico digestion of three sequences from the GenBank ***:Moroccan *** strains presented a certain level of genetic diversity and six distinct nagt-RFLP genotypes were *** of the six genotypes were exclusively identified in the Moroccan population of ***:variant M1(15%),variant M2(7.5%),and variant M3(2.5%).The most common genotype(65%),variant 2(2.5%),and variant 4(7.5%),were previously described in several countries with endemic *** analysis segregated our *** population into two distinct clusters,whereas variant M2 was clearly distinguished from both cluster I and cluster *** distribution highlights the degree of genetic variability among the Moroccan *** ***:The nagt PCR-RFLP method presented here showed an important genetic heterogeneity among Moroccan *** strains isolated from human and canine reservoirs with 6 genotypes *** of the six Moroccan nagt genotypes,have not been previously described and support the particular gen

关键词： Leishmania infantum Genetic variability N-acetylglucosamine-1-phosphate transferase PCR-RFLP Morocco

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What Factors Influence the Choice of Anesthesiology in a Moroccan Medical School?

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International Journal of Clinical Medicine 2022年第1期13卷 57-65页

作者： Abdelhamid Hachimi Soulaymane Rachda Mohamed El-Alaoui Leonard Biantona Bouebazebi rajaa Belmaati Meriem Essafti Fatima-Ezzahra Saroukh Mohamed Amine Medical Intensive Care Unit Faculty of Medicine and Pharmacy Cadi Ayyad University Marrakech Morocco Community Medicine and Public Health Department Research Laboratory Biosciences and Health Faculty of Medicine and Pharmacy Cadi Ayyad University Marrakech Morocco

Objective: To determine factors influencing anesthesiology choice among resident doctors at the medical school of Marrakech. Materials and Methods: We have conducted a descriptive cross-sectional study based on an anonymous questionnaire. Results: A total of 406/672 questionnaires were returned, with a female/male sex ratio of 1.07. The duration of the training (OR: 3.3;CI 95%: 1.74 - 6.23;p < 0.001), intellectual challenge (OR: 3.02;CI 95%: 1.69 - 5.37;p < 0.001), doctor-patient relationship (OR: 2.22;CI 95%: 1.02 - 4.84;p: 0.04), and financial aspects (OR: 2.14;CI 95%: 1.09 - 4.21;p: 0.02) were independent factors that influenced the choice of anesthesiology. Conclusion: we recommend the succeeding: 1) Support students in their choice;2) Correct misconceptions about certain specialties;3) Promote clinical clerkship;4) Encourage mentorship;5) Increase the salary of at-risk specialties.

关键词： Anesthesiology Career Choice Influencing Factors Resident Doctor

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Power Maximization and Control of Variable-Speed Wind Turbine System Using Extremum Seeking

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Journal of Power and Energy Engineering 2018年第1期6卷 51-69页

作者： Safanah M. Rafaat rajaa Hussein Control and Systems Engineering Department University of Technology Baghdad Iraq

Maximizing the power capture is an important issue to the turbines that are installed in low wind speed area. In this paper, we focused on the modeling and control of variable speed wind turbine that is composed of two-mass drive train, a Squirrel Cage Induction Generator (SCIG), and voltage source converter control by Space Vector Pulse Width Modulation (SPVWM). To achieve Maximum Power Point Tracking (MPPT), the reference speed to the generator is searched via Extremum Seeking Control (ESC). ESC was designed for wind turbine region II operation based on dither-modulation scheme. ESC is a model-free method that has the ability to increase the captured power in real time under turbulent wind without any requirement for wind measurements. The controller is designed in two loops. In the outer loop, ESC is used to set a desired reference speed to PI controller to regulate the speed of the generator and extract the maximum electrical power. The inner control loop is based on Indirect Field Orientation Control (IFOC) to decouple the currents. Finally, Particle Swarm Optimization (PSO) is used to obtain the optimal PI parameters. Simulation and control of the system have been accomplished using MATLAB/Simulink 2014.

关键词： Wind Turbine Indirect Field Orientation Control (IFOC) Maximum Power Point Tracking (MPPT) Extremum Seeking Control (ESC) Particle Swarm Op-timization (PSO) PI Controller

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Characterization of Some Jordanian Crude and Exhausted Olive Pomace Samples

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Green and Sustainable Chemistry 2013年第4期3卷 146-162页

作者： Khalid M. Tawarah rajaa A. Rababah Department of Chemistry Yarmouk University Irbid Jordan

In an attempt to provide a set of specifications for the use and trade of the olive pomace in Jordan, several samples of the crude and laboratory-prepared exhausted (oil-free) olive pomace have been subjected to a thorough thermochemical characterization. Such characterization included determination of fat content by using n-hexane and Soxhlet extractor, ultimate and proximate analyses obtained by using an elemental analyzer and a thermogravimetric procedure, respectively, gross and net calorific values obtained by using adiabatic oxygen bomb calorimetry, mineral content (ash), and analysis of the pyrolysis thermograms in terms of specified temperatures and residual masses associated with such temperatures as obtained under an inert atmosphere of nitrogen gas at a flow rate of 100 ml per min and a heating rate of 20°C per min from room temperature up to 600°C. The properties of both the crude and the exhausted olive pomace were compared. The gross calorific values and the results of the ultimate analyses for the two pomace types were found to correlate very well as indicated by the use of a literature correlation formula usually used for estimating the gross calorific value of a fuel when its ultimate analysis is known. Other literature correlation formulas used for estimating the gross calorific value from the proximate analysis data were also used to check the adequacy of our procedure for getting the proximate analysis from the?thermogravimetric pyrolysis thermograms.

关键词： Olive Pomace Heat of Combustion Thermogravimetric Analysis Ultimate Analysis Proximate Analysis Ash Pyrolysis

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Roscovitine synergizes with conventional chemo-therapeutic drugs to induce efficient apoptosis of human colorectal cancer cells

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World Journal of Gastroenterology 2008年第33期14卷 5162-5175页

作者： Mohamed Salah I Abaza Abdul-Majeed A Bahman rajaa J Al-Attiyah Molecular Biology Program Department of Biological Sciences Faculty of Science Kuwait UniversitySafaat 13006 Kuwait Department of Microbiology Faculty of Medicine Kuwait UniversitySafaat 13006 Kuwait

AIM: To examine the ability of cyclin-dependent kinase inhibitor (CDKI) roscovitine (Rosco) to enhance the antitumor effects of conventional chemotherapeutic agents acting by different mechanisms against human colorectal cancer. METHODS: Human colorectal cancer cells were treat-ed, individually and in combination, with Rosco, taxol, 5-Fluorouracil (5-FU), doxorubicine or vinblastine. The antiproliferative effects and the type of interaction of Rosco with tested chemotherapeutic drugs were de-termined. Cell cycle alterations were investigated by fluorescence-activated cell sorter FACS analysis. Apop-tosis was determined by DNA fragmentation assay. RESULTS: Rosco inhibited the proliferation of tumor cells in a time-and dose-dependent manner. The ef-ficacies of all tested chemotherapeutic drugs were markedly enhanced 3.0-8.42 × 103 and 130-5.28 × 103 fold in combination with 5 and 10 μg/mL Rosco, re-spectively. The combination of Rosco and chemothera-peutic drugs inhibited the growth of human colorectal cancer cells in an additive or synergistic fashion, and in a time and dose dependent manner. Rosco induced apoptosis and synergized with tested chemothera-peutic drugs to induce efficient apoptosis in human colorectal cancer cells. Sequential, inverted sequential and simultaneous treatment of cancer cells with combi-nations of chemotherapeutic drugs and Rosco arrested the growth of human colorectal cancer cells at various phases of the cell cycle as follows: Taxol/Rosco (G2/M-and S-phases), 5-FU/Rosco (S-phase), Dox/Rosco (S-phase) and Vinb/Rosco (G2/M-and S-phases). CONCLUSION: Since the eff icacy of many anticancer drugs depends on their ability to induce apoptotic cell death, modulation of this parameter by cell cycle inhibi-tors may provide a novel chemo-preventive and chemo-therapeutic strategy for human colorectal cancer.

关键词：直肠癌化学敏感作用细胞凋亡细胞周期协同作用

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Evaluation of Quality of Drinking Water in the City of Casablanca(Morocco)

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地学前缘 2009年第S1期16卷 7-7页

作者： Delhi rajaa Rhinane Kaoukaya Benzha Hilali Zidane Tahiri Department of Geology Ain Chock Faculty of Science Hassan Ⅱ University Department of Chemistry Ain Chock Faculty of Science Hassan Ⅱ University

This study falls within the framework of a partnership project between Lyonnaise des Eaux de Casablanca (LYDEC) and HassanⅡUniversity in ***’s overall objective is to evaluate the organoleptic quality of water feeding the great Wilaya of *** project has set specific targets based on monitoring water quality in the different levels of the chain of

关键词： quality organoleptic Bourgreg Oum Rbia physicochemical

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组织文化对摩洛哥建筑业绩效的影响

组织文化对摩洛哥建筑业绩效的影响

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作者：张雅娜（KODAD rajaa）东南大学

学位级别：硕士

建筑业对一个国家的经济影响很大。建设项目绩效较好将有效提高建设生产力,并将对经济产生积极影响。鉴于组织文化与企业有效性等结果之间存在显着的关系,并基于资源基础观点理论,本研究提出了一种调查组织文化对建筑企业绩效的影响的... 详细信息

建筑业对一个国家的经济影响很大。建设项目绩效较好将有效提高建设生产力,并将对经济产生积极影响。鉴于组织文化与企业有效性等结果之间存在显着的关系,并基于资源基础观点理论,本研究提出了一种调查组织文化对建筑企业绩效的影响的文化效率模型,尤其是在摩洛哥的情况下。在摩洛哥开展业务的当地承包公司的管理人员的答复是采用精心构建的问卷调查收集的。对收集到的问卷进行完整性检查,并编入社会科学统计软件包(第21版)进行分析。多元线性回归分析被用来评估组织文化对企业绩效的影响模型。研究表明,市场文化民主文化和家族文化对企业绩效有正向影响。层次文化对企业绩效有负面影响。此外,回归分析表明,市场文化可能是促进摩洛哥建筑公司业绩的文化背景,这可能会说明市场文化背景水平越高,摩洛哥建筑业的绩效水平就越高行业。这些结果可能对摩洛哥建筑公司培养正确的组织文化有所帮助,有助于提高公司的效率。该研究建议,应该在邻国进行进一步的研究,以发现这一结果是否对我们研究的国家特别重要,并深入了解这种关系。

关键词：组织文化绩效摩洛哥资源基础观计量经济分析

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