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Fabrication, characterization and response surface method optimization for quantum efficiency of fluorescent nitrogen-doped carbon dots obtained from carboxymethylcellulose of oil palms empty fruit bunch

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Chinese Journal of Chemical Engineering 2020年第2期28卷 584-592页

作者： Mohammed Abdullah issa Zurina Zainal Abidin Shafreeza Sobri Suraya Abdul-Rashid Mohd Adzir Mahdi Nor Azowa Ibrahim Musa Y.Pudza Department of Chemical and Environmental Engineering Faculty of EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Department of Computer&Communications Systems Engineering Faculty of EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Department of Chemistry Faculty of ScienceUniversiti Putra Malaysia43400 SerdangSelangorMalaysia

Bio based nitrogen doped carbon dots(N-CDs)were obtained from empty fruit bunch carboxymethylcellulose and ethylenediamine(EDA)through one-pot hydrothermal carbonization *** optimum as-formed NCDs were thoroughly characterized via Transmission electron microscopy(TEM),high-resolution TEM(HRTEM),Fourier transform infrared(FTIR),X-ray photoelectron spectra(XPS),UV–vis spectra(UV–Vis)and Fluorescence spectra(PL).Response surface methodology was statistically used to assess three independent variables that have major influence on the fluorescence quantum yield(QY),including temperature(230–270℃),time(2–6 h)and EDA mass(10%–23.3%).Based on analysis of variance(ANOVA)results,synthesis temperature was found to be the most influential factor on the QY,followed by time and EDA *** temperature,long synthesis time and high amount of EDA were satisfactorily enough for efficient carbonization conversion rate and obtaining highest QY of *** obtained quadratic model(R^2=0.9991)shows a good correlation between the experimental data and predicted *** optimum synthetic parameters are of 270℃temperature,6 h reaction time and 23.3%of EDA *** optimized as-made N-CDs exhibited blue photoluminescence with both excitation dependent/independent phenomena and high nitrogen *** maximum emission intensity was 426 nm at a maximum excitation wavelength of 320 nm,with a QY of up to 22.9%.XPS and FTIR data confirmed the existence of polar containing groups,such as carbonyl,carboxyl,hydroxyl and amino groups over the surface of N-CDs whereas nitrogen species in the form of(pyridinic and graphitic-N)were introduced in the aromatic carbon domains,which imparts the hydrophilic and photostability of *** into account the low-cost and sustainable production of N-CDs,this method considered a feasible route for converting low quality waste into value-added nanomaterials and utilizing for different functionalization processes and analytical applications.

关键词： Carbon dots Fluorescence Response surface methodology Optimization Nitrogen doped

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When the Blood Pressure Misleads You:A Diagnostic Conundrum in an Unusual Case of Coarctation

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Congenital Heart Disease 2021年第6期16卷 675-680页

作者： Eva Kapravelou Hugo issa Gordon Culham Martin Hosking Sanjiv K.Gandhi Shubhayan Sanatani Department of Pediatrics Division of CardiologyUniversity of British ColumbiaVancouverCanada Division of Pediatric Cardiothoracic Surgery University of British ColumbiaVancouverCanada Department of Pediatric Radiology British Columbia Children’s HospitalVancouverCanada

A 4-month-old previously healthy baby was found to be in congestive heart failure with LV dysfunction and a right aortic arch with severe coarctation,undetectable by blood pressure measurements.A cardiac CT and central blood pressure led to the diagnosis of a unique anatomic variant of aortic *** diagnosed the patient underwent surgery with an uncomplicated recovery.

关键词： Aorta coarctation right arch congenital heart disease

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Novel approach for the automated detection of allergy test using spectral imaging

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Journal of Biomedical Science and Engineering 2012年第8期5卷 416-421页

作者： issa Ibraheem Department of Biomedical Engineering Damascus University Damascus Syria

This paper proposes a novel approach for the automatic detection of allergy test (allergy lesion). A hyperspectral microscope system was used to image the test samples which were diagnosed by dermatologist. It was found that allergy of different levels, and healthy skin cells show absorption spectra, which are sufficiently characteristic and yet reproducible enough to allow for differentiation when using a spectroscopic system. Principal components analysis was used to extract relevant features that could be used for classification from these spectra. Preliminary results indicate that the different types of allergy cells can be reliably distinguished by these features. We conclude that hyperspectral microscopic analysis is a promising approach for improving and automating the diagnosis of allergy test as well as another skin lesions.

关键词： allergy-test Classification Spectral Imaging Principal Components Analysis Linear Discriminant

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Surface hardness,thermal,optical,and photon attenuation coefficients assessment for dysprosium-doped tellurite glasses

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Journal of Rare Earths 2023年第7期41卷 1083-1090,I0004页

作者： Hesham M.H.Zakaly D.E.Abulyazied H.A.Saudi B.M.alotaibi Shams A.M.issa Institute of Physics and Technology Ural Federal UniversityYekaterinburg620002Russia Faculty of Science Al-Azhar UniversityAssuit BranchAssuit71524Egypt Polymer Lab Department of PetrochemicalsEgyptian Petroleum Research InstituteNasr CityCairoEgypt Department of Physics Faculty of ScienceUniversity of TabukTabukSaudi Arabia Physics Department Faculty of ScienceAl-Azhar University(Girls Branch)Nasr CityCairoEgypt Department of Physics College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia

Using a melt-cooling process with the host glass,Dy_(2)O_(3)(1 wt%,2 wt%,3 wt%,and 4 wt%) doped tellurite glasses were produced.A(65-x)TeO_(2)-20B_(2)O_(3)-10al_(2)O_(3)-SGeO_(2)-xDy_(2)O_(3) glass system was analyzed by Xray *** patterns have a hump at 2θ=27°-29° and no sharp peaks,indicating that all the glass samples are *** Vickers microhardness determines how resistant a glass is to persistent deformation produced by a harder *** scanning calorimetry(DSC) at 300-550℃ was used to evaluate the thermal properties of the Dy_x glass *** glass transition temperature T_g(small endothermic peak),start crystallization temperature T_x and crystallization temperature T_c can all be seen on the DSC thermogram(exothermic peaks).The UV-Vis transmittance and absorption spectra were *** optical data show that the values of E_d^(ir),E_g^(Ind) and E_U decrease as the amount of Dy_(2)O_(3)increases,indicating a narrowing of the tails due to localized states in the forbidden gap.A concentration quenching event occurs when Dy^(3+) concentrations are above a certain threshold(1%).The addition of Dy_(2)O_(3) increases glass density,while the addition of other Dy(Ⅲ) oxides increases sample *** radiation shielding values change as a consequence of density *** sample with the highest amount of Dy_(2)O_(3)(Dy_(4)) has stronger radiation shielding characteristics;hence,it is superior in terms of shielding outcomes at all energy *** Dy_x samples can be used in various forms of ionizing radiation shielding.

关键词： Melt-cooling process DSC Dysprosium(Ⅲ)oxides Surface hardness Photon attenuation Rare earths

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An Approximation for the Entropy Measuring in the General Structure of SGSP_(3)

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Computers, Materials & Continua 2022年第12期73卷 4455-4463页

作者： Zeeshan Saleem Muftiand Muhammad Hussain Kamel Jebreen Muhammad Haroon Aftab Mohammad issa Sowaity Zeeshan Saleem Mufti Muhammad Hussain Biostatistics and Clinical Research Department University Hospital LariboisièreAP-HPUniversite’de ParisParis75010France Department of Mathematics An-Najah National UniversityNablusP400Palestine Department of Mathematics Palestine Technical University-KadoorieHebronP766Palestine Department of Mathematics and Statistics the University of LahoreLahore54000Pakistan Department of Mathematics Palestine Polytechnic UniversityHebronP766Palestine Department of Mathematics COMSATS University IslamabadLahore campusLahore54000Pakistan

In this article,we calculate various topological invariants such as symmetric division degree index,redefined Zagreb index,VL index,first and second exponential Zagreb index,first and second multiplicative exponential Zagreb indices,symmetric division degree entropy,redefined Zagreb entropy,VL entropy,first and second exponential Zagreb entropies,multiplicative exponential Zagreb *** take the chemical compound named Proanthocyanidins,which is a very useful polyphenol in human’s *** are very beneficial for one’s *** chemical compounds are extracted from grape *** are tremendously anti-inflammatory.A subdivision formof this compound is presented in this *** compound named subdivided grape seed Proanthocyanidins is abbreviated as SGSP_(3).This network SGSP_(3),is converted and modeled into its mathematical graphical formation with the support of the latest mathematical *** have also developed many closed formulas for the measurement of entropy for the general chemical structure of the subdivided grape seed Proanthocyanidins *** achieved outcomes can be correlated with the chemical version of SGSP_(3) to get a better understanding of its biological as well as physical features.

关键词： Symmetric division degree redefined Zagreb VL index exponential multiplicative Zagreb subdivided grape seed Proanthocyanidins graphical model genetics entropy

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Trans-anal endoscopic microsurgery for non- adenomatous rectal lesions

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World Journal of Gastrointestinal Surgery 2023年第11期15卷 2406-2412页

作者： Dafna Shilo Yaacobi Eliahu Y Bekhor Muhammad Khalifa Tal E Sandler Nidal issa Department of Plastic Surgery and Burns Rabin Medical CenterPetah Tikva 4941492Israel Department of Surgery Rabin Medical CenterPetah Tikva 4941492Israel Department of Anesthesiology Rabin Medical CenterPetah Tikva 4941492Israel

BACKGROUND Trans-anal endoscopic microsurgery(TEM)enables a good visualization of the surgical field and is considered the method of choice for excision of adenomas and early T1 rectal *** rectum and retro-rectal space might be the origin of uncommon neoplasms,benign and aggressive,certain require radical trans-abdominal surgery,while others can be treated by a less aggressive *** this study we report outcomes in patients undergoing TEM for rare and non-adenomatous rectal and retro-rectal lesions over a period of 11 *** Between January 2008 to December 2019 a retrospective analysis was completed for all patients who underwent TEM for non-adenomatous rectal lesion or retro-rectal mass in our *** were discharged once diet was well tolerated and no complications were *** were evaluated at 3 wk post operatively,then at 3-mo intervals for the first 2 years and every 6 mo depending on the nature of the final *** examination and rectoscopy were performed during each of the follow-up *** Out of 198 patients who underwent TEM during the study period,18 had non-adenomatous rectal or retro-rectal *** age was 47 *** mean size of the lesions was 2.9 mm,with a mean distance from the anal margin of 7.9 *** surgical time was 97.8 *** were no intra-operative neither late post-operative *** length of stay was 2.5 *** patient follow-up duration was 42 *** TEM allows for reduced morbidity given its minimally invasive *** should be familiar with the technique but careful patient selection should be *** can be used safely for uncommon rectal and selected retro-rectal lesions without compromising *** believe that it should be reasonably considered as one of the surgical methods when treating rare lesions.

关键词： Trans-anal endoscopic microsurgery Rectal lesions MicrosurgeryTrans-anal endoscopic microsurgery Rectal lesions Microsurgery

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Developing an Assessment Model for Factors Affecting the Quality in the Construction Industry

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Journal of Civil Engineering and Architecture 2012年第3期6卷 364-371页

作者： Usama Hamed issa Civil Engineering Department Faculty of Engineering Minia University Minia Egypt

Quality is considered as one of the most important elements in the construction industry. The factors affecting quality in the construction industry should be assessed. This paper aims to introduce a new model to assess these factors. The model is namely Fuzzy Assessment Model for Quality （FAMQ）. Fuzzy set theory provides a useful way to deal with ill-defined and complex problems in a decision-making environment that incorporates vagueness. The proposed model employs the combined effect of both; the factors probability of occurrence and their impacts on the quality of construction. Twenty five logical rules for each factor were implemented in the model. The model was evaluated using data that collected from the infrastructure projects in Egypt. It was applied to many factors that affect the quality of this kind of projects as a case study. The results of the study proved that the proposed model can be used successfully in the assessment of factors affecting quality in the construction industry. In addition, the results provided a platform of useful assessment reference to those infrastructure＇s finns, who plan to establish their businesses in Egypt.

关键词： Quality in construction fuzzy Egypt.

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EFL for Survival Outside the L 1 Environment： An Empirical Study of Arab High School Learners

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Sino-US English Teaching 2017年第7期14卷 425-435页

作者： issa AI-Qaderi University of Warsaw Warsaw Poland

Teaching English as a foreign language （EFL） has been growing throughout the Arab world and hence English hasbecome an obligatory subject in the school curriculum in most Arab countries. However, teaching EFL to Arablearners outside the L! environment becomes more challenging. In such a setting, Arab EFL learners use mostlyspoken English for survival, i.e., English acts as a genuine lingua franca outside the classroom and this requireswell-qualified teachers as well as a professional educational environment inside the classroom. For survival, thespeaking skill becomes inevitable. The study attempts to investigate the factors that might affect Arab high schoollearners＇ EFL speaking performance in Poland. The data collected come from two sources： a questionnaire that wasdistributed to Arab EFL high school learners （N = 30） studying at the Libyan private school and Dar al salaamprivate school of Iraq in Warsaw and semi-structured interviews with instructors （N = 3）. Both quantitative andqualitative approaches have been employed. The findings reveal that students encounter problems in EFL speakingskill due to three main factors： teacher-related variables, curricular-variables, and learner-variables.

关键词： speaking skill, environment, teacher-related variables, curricular-variables, learner-variables

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Modeling of the 3D spatio-temporal thermal profile of joule-class Yb3+-based laser amplifiers

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High Power Laser Science and Engineering 2019年第3期7卷 53-59页

作者： issa Tamer Sebastian Keppler Jorg Komer Marco Hornung Marco Hellwing Frank Schorcht Joachim Hein Malte C.Kaluza Helmholtz-Institute Jena Frobelstieg 307743 JenaGermany Friedrich-Schiller-University Jena Max-Wien Platz 107743 JenaGermany

Thermal profile modification of an active material in a laser amplifier via optical pumping results in a change in the material’s refractive index,and causes thermal expansion and stress,eventually leading to spatial phase aberrations,or even permanent material *** this purpose,knowledge of the 3D spatio-temporal thermal profile,which can currently only be retrieved via numerical simulations,is critical for joule-class laser amplifiers to reveal potentially dangerous thermal features within the pumped active *** this investigation,a detailed,spatio-temporal numerical simulation was constructed and tested for accuracy against surface thermal measurements of various endpumped Yb^3+-doped laser-active *** measurements and simulations show an excellent agreement and the model was successfully applied to a joule-class Yb3+-based amplifier currently operating in the POLARIS laser system at the Friedrich-Schiller-University and Helmholtz-Institute Jena in Germany.

关键词： diode-pumped solid-state lasers high intensity lasers laser amplifiers spatio-temporal thermal profile modeling ytterbium

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Optimizing Resource allocation Framework for Multi-Cloud Environment

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Computers, Materials & Continua 2023年第5期75卷 4119-4136页

作者： Tahir alyas Taher M.Ghazal Badria Sulaiman alfurhood Ghassan F.issa Osama ali Thawabeh Qaiser Abbas Department of Computer Science Lahore Garrison UniversityLahore54000Pakistan School of Information Technology Skyline University CollegeUniversity City Sharjah1797SharjahUAE Center for Cyber Security Faculty of Information Science and TechnologyUniversiti Kebansaan Malaysia(UKM)43600BangiSelangorMalaysia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11564Saudi Arabia Skyline University College University City Sharjah1797SharjahUAE Faculty of Computer and Information Systems Islamic University of Madinah Madinah42351Saudi Arabia

Cloud computingmakes dynamic resource provisioning more *** a functioning service is crucial,and changes are made when particular criteria are *** research explores the decentralized multi-cloud environment for allocating resources and ensuring the Quality of Service(QoS),estimating the required resources,and modifying allotted resources depending on workload and parallelism due to *** allocation is a complex challenge due to the versatile service providers and resource *** engagement of different service and resource providers needs a cooperation strategy for a sustainable quality of *** objective of a coherent and rational resource allocation is to attain the quality of *** also includes identifying critical parameters to develop a resource allocation mechanism.A framework is proposed based on the specified parameters to formulate a resource allocation process in a decentralized multi-cloud *** three main parameters of the proposed framework are data accessibility,optimization,and *** an optimization technique,these three segments are further divided into subsets for resource allocation and long-term service *** CloudSim simulator has been used to validate the suggested *** experiments have been conducted to find the best configurations suited for enhancing collaboration and resource allocation to achieve sustained *** results support the suggested structure for a decentralized multi-cloud environment and the parameters that have been determined.

关键词： Multi-cloud query optimization cloud resources allocation modelling virtualization

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