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Physical and geometrical parameters of CVBS XIV:the two nearby systems HIP 19206 and HIP 84425

Research in Astronomy and Astrophysics 2021年第7期21卷 62-70页

作者： Mashhoor A.Al-Wardat Enas Abu-Alrob Abdallah M.Hussein Mohammad K.Mardini Ali A.Taani Hatem S.Widyan Zahraa T.Yousef Hamid M.Al-Naimiy nihad a.yusuf Department of Applied Physics and Astronomy University of SharjahSharjahUAE Sharjah Academy for Astronomy Space Science and TechnologySharjahUAE Department of Physics Al al-Bayt UniversityMafraq25113 Jordan Key Lab of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Physics Department Faculty of ScienceAl-Balqa Applied University19117 SaltJordan Department of Applied Physics Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Department of Physics Yarmouk UniversityIrbid21163Jordan

Data release 2(DR2) from the Gaia mission was of great help in precise determination of fundamental parameters of Close Visual Binary and Multiple Systems(CVBMSs), especially masses of their components, which are crucial parameters in understanding formation and evolution of stars and galaxies. This article presents the complete set of fundamental parameters for two nearby close visual binary systems(CVBSs), which are HIP 19206 and HIP 84425. We utilised a combination of two methods;the first one is Tokovinin's dynamical method to solve the orbit of the system and to estimate orbital elements and the dynamical mass sum, and the second one is Al-Wardat's method for analysing CVBMSs to estimate the physical parameters of the individual components. The latest method employs grids of Kurucz lineblanketed plane parallel model atmospheres to build synthetic Spectral Energy Distributions(SEDs) of the individual components. Trigonometric parallax measurements given by Gaia DR2 and Hipparcos catalogues are used to analyse the two systems. The difference in these measurements yielded slight discrepancies in the fundamental parameters of the individual components, especially masses. So, a new dynamical parallax is suggested in this work based on the most convenient mass sum as given by each of the two methods. The new dynamical parallax for the system HIP 19205 of 22.97±0.95 mas coincides well with the trigonometric one reported recently(in December 2020) by Gaia EDR3 of 22.3689 ± 0.4056 mas. The positions of the components of the two systems on the evolutionary tracks and isochrones are plotted, which suggest that all components are solar-type main sequence stars. Their most probable formation and evolution scenarios are also discussed.

关键词： binaries:close binaries:visual-stars:fundamental parameters stars:individual:HIP 19206 and HIP 84425

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Physical and geometrical parameters of CVBS Ⅺ: Cou 1511(HIP 12552)

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Research in Astronomy and Astrophysics 2016年第11期16卷 13-18页

作者： Mashhoor A. Al-Wardat Mohammad H. El-Mahameed nihad A. yusuf Awni M. Khasawneh Suhail G. Masda Physics Department A1 al-Bayt University PO Box: 130040 Mafraq 25113 Jordan Department of Physics A1-Hussein Bin Talal University Maan 71111 Jordan Department of Physics Yarmouk University Irbid 21163 Jordan King Abdullah I School for Graduate Studies and Scientific Research Princess Sumaya University for Technology PO Box 1438 Amman 11941 Jordan Royal Jordanian Geographic Center Amman 11941 Jordan Astrophysikalisches Institut und Universitaits-Sternwarte Jena FSU Jena 07745 Jena Germany

Model atmospheres of the close visual binary star Cou 1511 （HIP 12552） are constructed using grids of Kuruz＇s blanketed models to build the individual synthetic spectral energy distributions （SEDs） for both components. These synthetic SEDs are combined together for the entire system and compared with the observational one following A1-Wardat＇s complex method for analyzing close visual binary stars. The entire observational SED of the system is used as a reference for comparison between the synthetic SED and the observed one. The parameters of both components are derived as： Teff = 6180 4- 50 K, Tebfr = 5865 ＋ 70 K, log 9a = 4.35 ± 0.12, log 9b = 4.45± 0.14, Ra = 1.262 ± 0.08 R⊙^eff, Rb = 1.006 ± 0.07 R⊙^ett, La = 2.09 -4- 0.10 L⊙ and Lb = 1.08 ± 0.12 L⊙, with spectral types F8V and G1.5V for components （a, b） respectively and age of 3.0 ± 0.9 Gyr. A modified orbit of the system is built and the masses of the two components are calculated as Ma = 1.17 ±0.11 Me and Mb = 1.06 ± 0.10 Me.

关键词： binaries -- visual stars -- fundamental parameters stars -- Cou 1511 (Hip 12552)

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A survey of machine learning techniques for detecting and diagnosing COVID-19 from imaging

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Quantitative Biology 2022年第2期10卷 188-207页

作者： Aishwarza Panday Muhammad Ashad Kabir nihad Karim Chowdhury Department of Computer Science&Engineering Stamford UniversityDhaka 1217Bangladesh School of Computing and Mathematics Charles Sturt UniversityNSW 2795Australia Department of Computer Science&Engineering University of ChittagongChittagong 4349Bangladesh

Background: Due to the limited availability and high cost of the reverse transcription-polymerase chain reaction (RT- PCR) test, many studies have proposed machine learning techniques for detecting COVID-19 from medical imaging. The purpose of this study is to systematically review, assess and synthesize research articles that have used different machine learning techniques to detect and diagnose COVID-19 from chest X-ray and CT scan ***: A structured literature search was conducted in the relevant bibliographic databases to ensure that the survey solely centered on reproducible and high-quality research. We selected papers based on our inclusion ***: In this survey, we reviewed 98 articles that fulfilled our inclusion criteria. We have surveyed a complete pipeline of chest imaging analysis techniques related to COVID-19, including data collection, pre-processing, feature extraction, classification, and visualization. We have considered CT scans and X-rays as both are widely used to describe the latest developments in medical imaging to detect ***: This survey provides researchers with valuable insights into different machine learning techniques and their performance in the detection and diagnosis of COVID-19 from chest imaging. At the end, the challenges and limitations in detecting COVID-19 using machine learning techniques and the future direction of research are discussed.

关键词： COVID-19 machine learning deep learning detection classification diagnosing X-ray CT scan

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Synthesis of 1,3-Oxazepine Derivatives Derived from 2-(1H-Benzo[d][1,2,3]Triazol-1-yl) Acetohydrazide by Using Microwave Irradiation

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International Journal of Organic Chemistry 2017年第3期7卷 219-228页

作者： nihad Ismail Taha Department of Chemistry College of Science Kirkuk University Kirkuk Iraq

A series of Schiff base and their derivative (oxazepine) have been synthesized. 8-hydrazone(schiff-bases) derivatives type (E)-2-(1H-benzo[d][1,2,3]triazole-1-yl)-N-(substituted benzylidene)aceto-hydrazide were prepared by condensation 1H-benzo[d][1,2,3]triazol-1-yl)hydrazine with various aromatic aldehyde in ethanol in the presence of dimethyl formamid or acetic acid as catalyst by using MWI to yield the Schiff bases. These Schiff’s base on treatment with Maleic anhydride in dry conditions by using MWI to give 7-membered heterocyclic ring system (oxezapine) of (2-(1H)benzo[d][1,2,3]triazol-1-yl)-N-(2-(substituted penyl)-4, 7-dioxo-4,7-dihydro-1,3-oxazepin-3-(2H)-yl)acetamide. The purity of the compounds was confirmed by TLC. The final products were identified by their melting point, IR, 1HNMR, and UV-visible spectra.

关键词： Hydrazone Microwave Oxezapine Benzotriazole Hydrazine

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Waste-minimized C(sp^(3))-H activation for the preparation of fused N-heterocycles

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Green Synthesis and Catalysis 2023年第3期4卷 240-245页

作者： nihad Salameh Francesco Minio Gabriele Rossini Assunta Marrocchi Luigi Vaccaro Laboratory of Green S.O.C.-Dipartimento di Chimica Biologia e BiotecnologieUniversita Degli Studi di PerugiaVia Elce di Sotto 8Perugia 06123Italy

By exploiting the combined use of a heterogeneous recyclable palladium(II)-bis(N-heterocyclic carbene)catalyst and cyclopentyl methyl ether(CPME)as a convenient recoverable safer reaction medium,an effective wasteminimized approach has been developed for the intramolecular Pd-catalyzed C(sp3)-H activation of methyl pyrrole *** synthetic tools has allowed to access condensed N-heterocycles generally endowed with biological activities and representatively are the core motif of complex molecules such as Mitomycines and *** heterogeneous catalytic system could be recovered and reused up to representative five runs without any loss in *** target products(19 examples)have been obtained selectively and with excellent isolated yields up to 93%.The approach leads to the definition of a protocol with a very good E-factor(21)which is much lower(up to 98%)than those of comparable literature *** green metrics have been calculated and the data collected demonstrate that our newly developed protocol is very promising in terms of its environmental impact profile.

关键词： C-H functionalization C-H activation Sustainable chemistry Waste-minimization Heterogeneous catalysis Safe reaction medium

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Cardiovascular co-morbidity in chronic kidney disease:Current knowledge and future research needs

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World Journal of Nephrology 2014年第4期3卷 156-168页

作者： Hudaifa Alani Asad Tamimi nihad Tamimi Broomfield Hospital Mid Essex NHS Trust University College London Hospital Pfizer Worldwide Research and Development

Chronic kidney disease(CKD) is recognised as a health concern globally and leads to high rates of morbidity,mortality and healthcare *** is itself an independent risk factor for unfavorable health outcomes that include cardiovascular disease(CVD).Coronary artery disease is the primary type of CVD in CKD patients and a significant cause of death among renal transplant *** and non-traditional risk factors for CVD exist in patients with *** factors include smoking,hypertension,dyslipidemia and diabetes which are highly prevalent in CKD ***-traditional risk factors of CKD are mainly uraemiaspecific and increase in prevalence as kidney function *** examples of uraemia-specific risk factors that have been well documented include low levels of haemoglobin,albuminuria,and abnormal bone and mineral *** interventions targeted at more traditional risk factors which contribute to CVD,have not had the desired effect on lowering CVD events and mortality in those suffering with *** research is warranted to delineate clear evidence to the benefit of modifying non-traditional risk factors.

关键词： Cardiovascular disease Chronic kidney disease Risk factors Inflammation

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Microwave Preparation and Spectroscopic Investigation of Binuclear Schiff Base Metal Complexes Derived from 2,6-Diaminopyridine with Salicylaldehyde

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International Journal of Organic Chemistry 2017年第4期7卷 412-419页

作者： Hasan A. Mohammed nihad Ismeal Taha Department of Chemistry College of Science University of Kirkuk Kirkuk Iraqi

The binuclear Schiff base complexes prepared by condensation 2,6-diamino-pyridine and salicylaldehyde (LH) by using microwave and adding metal salts to ligand by same ratio. The Schiff base ligand was checked by infrared, electronic spectra and 1HNMR spectroscopy and prepared complexes characterized by molar conductivity, infrared, electronic spectra and susceptibility measurements. The values of molar conductivities reveal that the complexes are non-electrolytes, from obtained data of electronic spectra and magnetic moment, an octahedral geometry was suggested, coordinated to the metal ions in a manner with N donor sites of imine groups, and oxygen of phenolic OH group.

关键词： Schiff Base Binuclear Metal Complexes 2 6-Diaminopyridine Salicylaldehyde

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Neutrophilia-Inducing Deferoxamine in Mice Infected with <i>Staphylococcus aureus</i>

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Open Journal of Pathology 2013年第2期3卷 99-106页

作者： Mohemid M. Al-Jebouri nihad A. Jafar Department of Microbiology College of Medicine University of Tikrit Tikrit Iraq

The ability to sequester iron is a primary defense mechanism against bacterial infection. Iron chelation therapy has been considered as a possible treatment for various infectious diseases. S. aureus isolated from neonatal septicemia were used to study the effect of deferoxamine and sub-minimal inhibitory concentration of gentamicine on some virulence factors of this isolates. Also an experimental sepsis was inducted in mice and treated with gentamicin and deferoxamine. The expression of virulence factor (alpha-hemolysin, beta-hemolysin, delta-hemolysin, coagulase, and DNase) by Staphylococcus?aureus isolates was significantly decreased (p < 0.05) after exposure to DFO and/or gentamicin. The data of the present study showed that using of DFO led to significant decrease (p < 0.05) in the mortality rate of mice infected with S. aureus. In a murine model of S. aureus sepsis, deferoxamine treatment had an additional effect on survival and bacterial eradication from the organs of septicemic mice. In vitro exposure of S. aureus isolated to gentamicin and deferoxamine led to a decrease in the production of some virulence factors by these isolates.

关键词： Neutrophilia Deferoxamine Gentamicin S. aureus Pathology

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Superior mesenteric artery syndrome caused by weight loss in a malnourished Syrian man

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Gastroenterology Report 2019年第3期7卷 223-225,I0003页

作者： Ziad Aljarad nihad Mahli Mahmoud Nasser Majd Alobied Mamdouh Alkhaled M.Wafa Hamoud Alhussein Ahmad Alhamid Ahmad Mouakeh Ahmad Sankari Tarabishi Department of Gastroenterology Aleppo University HospitalAleppoSyria Department of Surgery Aleppo University HospitalAleppoSyria Department of Internal Medicine Aleppo University HospitalAleppoSyria Faculty of Medicine University of AleppoAleppoSyria

Superior mesenteric artery syndrome is a rare cause of upper gastrointestinal obstruction in which the third part of the duodenum is compressed between the superior mesenteric artery and the abdominal aorta,and the compression of the duodenum is caused by a narrowed aortomesenteric *** report in this case a 35-year-old patient who came with features of small bowel obstruction,weight loss and had a history of malnutrition because of ***-slice computerized tomography showed a narrowed aortomesenteric angle and *** treatment was presented and,after 3 months of observation,the patient gained weight.

关键词： superior mesenteric artery syndrome aortomesenteric angle upper gastrointestinal obstruction malnutrition

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Precision Laser Beam Path Tracking Control System for Position Measurement Using PSD Sensor

Precision Laser Beam Path Tracking Control System for Positi...

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作者： nihad ABDALLA Shi LIU Ahmed ABDELRAHIM School of Control and Computer Engineering North China Electric Power University

Position sensitive detector（PSD） is an optical position sensor that can measure a position of the light spot in one or two-dimensions on sensor *** PSD is precision semiconductor optical sensor that produces output currents related to the "Centre of mass" of light incident on the surface of the device used in the measurement there are many advantages including a good positioning accuracy for fast response time and very simple signal conditioning circuits.A precise control system has been designed in this paper using a new and modern algorithm with a closed-loop system to obtain accurate tracking of the position and speed of the radiation used in the measurement of the specific physical *** proposed control model about laser beam path controlled using a new type of controller named PSD fuzzy controller with feedback through PSD sensor,also the FOC method was applied to the hybrid stepper motor to control the position and speed with four rings *** algorithm will realize better rise time and less overshoot better and detailed analysis is carried out to confirm the viability of the proposed system.

关键词： PSD sensor Fuzzy controller Hybrid stepper motor Optoelectronic system

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