Spectral, Magnetic, and Thermal Properties of Some Thiazolylazo Complexes

Masoud, M.S.,Mohamed, G.B.,Abdul-Razek Y.H.,Ali A.E.,Khairy F.N. 대한화학회 2002 대한화학회지 Vol.46 No.2

Thiazolylazo 화합물과 barbituric산, uracil, thiouracil, citrazinic산 chromotrotropic산, gallict산, pyrogallol 그리고 salicylic산의 Co(II), Ni(II) 그리고 Cu(II) 착화합물의 제조하였고, NMR, IR, 그리고 전기 흡수 스펙트럼에 대한 pHdudgid에 의하여 규명하였다. 이온화형태, 전기적 전이 그리고 해리상수에 대하여 설명하였다. 구리 착화합물은 등방형 ESR스펙트럼이었으며 자기적으로 궤도 기여를 갖는 묽은 성질이었다. 상세한 DTA데이타를 얻었고, 그 결과를 토론하였다. The thiazolylazo compounds and their Co(II), Ni(II) and Cu(II) complexes of barbituric acid, uracil, thiouracil, citrazinic acid, chromotropic acid, gallic acid, pyrogallol and salicylic acid were pre-pared and characterized by NMR , IR and the effect of pH on the electronic absorption spectra . The mode of ionization, the electronic transitions and the dissociation constants were discussed. The stoichiometries of the complexes were of 1:1, 2:1 and 3:2 (M:L). The copper complexes are of isotropic ESR spectra (except that of gallic acid which showed a complicated one) and are of magnetically diluted behaviour with orbital con-tribution. Detailed DTA data were obtained and discussed.

Prevalence and Molecular Characterization of Methicillin-Resistant Staphylococcus aureus from Nasal Specimens: Overcoming MRSA with Silver Nanoparticles and Their Applications

Abo-Amer Aly E.,Gad El-Rab Sanaa M. F.,Halawani Eman M.,Niaz Ameen M.,Bamaga Mohammed S. 한국미생물·생명공학회 2022 Journal of microbiology and biotechnology Vol.32 No.12

Staphylococcus aureus is a cause of high mortality in humans and therefore it is necessary to prevent its transmission and reduce infections. Our goals in this research were to investigate the frequency of methicillin-resistant S. aureus (MRSA) in Taif, Saudi Arabia, and assess the relationship between the phenotypic antimicrobial sensitivity patterns and the genes responsible for resistance. In addition, we examined the antimicrobial efficiency and application of silver nanoparticles (AgNPs) against MRSA isolates. Seventy-two nasal swabs were taken from patients; MRSA was cultivated on Mannitol Salt Agar supplemented with methicillin, and 16S rRNA sequencing was conducted in addition to morphological and biochemical identification. Specific resistance genes such as ermAC, aacA-aphD, tetKM, vatABC and mecA were PCR-amplified and resistance plasmids were also investigated. The MRSA incidence was ~49 % among the 72 S. aureus isolates and all MRSA strains were resistant to oxacillin, penicillin, and cefoxitin. However, vancomycin, linezolid, teicoplanin, mupirocin, and rifampicin were effective against 100% of MRSA strains. About 61% of MRSA strains exhibited multidrug resistance and were resistant to 3-12 antimicrobial medications (MDR). Methicillin resistance gene mecA was presented in all MDR-MRSA strains. Most MDR-MRSA contained a plasmid of > 10 kb. To overcome bacterial resistance, AgNPs were applied and displayed high antimicrobial activity and synergistic effect with penicillin. Our findings may help establish programs to control bacterial spread in communities as AgNPs appeared to exert a synergistic effect with penicillin to control bacterial resistance.

Morphological study of porous aromatic schiff bases as a highly effective carbon dioxide storages

Rehab Hammoda,Naser Shaalan,Mohammed H. Al-Mashhadani,Dina S. Ahmed,Rahimi M. Yusop,Ali H. Jawad,Emad Yousif 한국분석과학회 2023 분석과학 Vol.36 No.5

Carbon dioxide (CO2) capture and storage is a critical issue for mitigating climate change. Porous aromatic Schiff base complexes have emerged as a promising class of materials for CO2 capture due to their high surface area, porosity, and stability. In this study, we investigate the potential of Schiff base complexes as an effective media for CO2 storage. We review the synthesis and characterization of porous aromatic Schiff bases materials complexes and examine their CO2 sorption properties. We find that Schiff base complexes exhibit high CO2 adsorption capacity and selectivity, making them a promising candidate for use in carbon capture applications. Moreover, we investigate the effect of various parameters such as temperature, and pressure on the CO2 adsorption properties of Schiff base complexes. The Schiff bases possessed tiny Brunauer-Emmett- Teller surface areas (4.7-19.4 m2/g), typical pore diameters of 12.8-29.43 nm, and pore volumes ranging from 0.02-0.073 cm3/g. Overall, our results suggest that synthesized complexes have great potential as an effective media for CO2 storage, which could significantly reduce greenhouse gas emissions and contribute to mitigating climate change. The study provides valuable insights into the design of novel materials for CO2 capture and storage, which is a critical area of research for achieving a sustainable future.

Study of Thin Double-Gap RPCs for the CMS Muon System

K. S. Lee,S. W. Cho,S. Choi,B. Hong,M. Kang,J. H. Lim,Y. M. Jo,S. K. Park,K. R. Ryoo,R. Aly,S. Aly,Y. Assran,A. Mohamed,A. Mahrous,S. Constantini,M. Abbrescia,A. Gelmi,M. Maggi,G. Iaselli,G. Pugliese 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.73 No.8

High-sensitivity double-gap phenolic resistive plate chambers (RPCs) are studied for the Phase-2 upgrade of the Compact Muon Solenoid (CMS) muon system at high pseudorapidity . Whereas the present CMS RPCs have a gas gap thickness of 2 mm, we propose to use thinner gas gaps, which will improve the performance of these RPCs. To validate this proposal, we constructed double-gap RPCs with two different gap thicknesses of 1.2 and 1.4 mm by using high-pressure laminated plates having a mean resistivity of about 5 1010 -cm. This paper presents test results using cosmic muons and 137Cs gamma rays. The rate capabilities of these thin-gap RPCs measured with the gamma source exceed the maximum rate expected in the new high- endcap RPCs planned for future Phase-2 runs of the Large Hadron Collider (LHC).

Histopathological and genetic changes proved the anti‑cancer potential of free and nano‑capsulated sinapic acid

Doaa A. Badr,Mohamed E. Amer,Wagih M. Abd‑Elhay,Mohamed S. M. Nasr,Tamer M. M. Abuamara,Harbi Ali,Aly F. Mohamed,Maha A. Youssef,Nasser S. Awwad,Yi‑Hsu Ju,Ahmed E. Fazary 한국응용생명화학회 2019 Applied Biological Chemistry (Appl Biol Chem) Vol.62 No.5

Cancer is known to be a fierce disease that causes a large percentage of the deaths worldwide. The common cancer treatments; chemotherapy, radiotherapy and surgery are known for their severe side effects; therefore scientists are working on finding solutions to reduce these drawbacks. One of these treatment systems is the sustained released drugs formulations, these systems depend on the encapsulation of the chemotherapy within an emulsifying agent, in order to obtain a slow drug release of low doses over long time intervals. In this study, the anti-cancer effects of free and encapsulated sinapic acid was tested against lung (A549), and colon (CaCo2) cancer cell lines, along with normal fibroblast cells (HFB4) as a negative control. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was performed for IC50 evaluation, also cell cycle assay was performed to detect cell cycle arrest status and related anti-apoptotic and pro-apoptotic; Blc-2, BAX, and P53 gene profile fold changes post cellular treatment. Data recorded revealed that encapsulated SA showed a lower toxicity than the free form to both cell lines and also to the normal cells. The cell cycle analysis showed a cell cycle arrest at the G2/M phase post cell treatment with the free and encapsulated sinapic acid accompanied with up regulation of Bax and P53 and a down regulation of Blc-2 genes in both cell lines. The data suggest a promising anti-cancer and anti-proliferative potential of free and encapsulated sinapic acid. Also they show that the anti-cancer effect of free and encapsulated sinapic acid is quite close.

The bio-composites (Hydroxyapatite/High-density polyethylene) materials reinforced with Multi-walled carbon nanotubes for bone tissue repair

Ali A. Al-allaq,Jenan S. Kashan,Mohamed T. El-Wakad,Ahmed M. Soliman 한양대학교 세라믹연구소 2021 Journal of Ceramic Processing Research Vol.22 No.4

Due to the predominance diseases such as bone fracture, bone cancer, and osteoporosis Worldwide. There is a developingrequirement for synthesizing biomaterials for bone repair or substitute due to the predominance of bone fracture, bone cancer,and osteoporosis. In this study, multi-wall carbon nanotubes (MWCNT) of (0.6%, 1%, 1.4%, 2%) wt.% and High-densitypolyethylene HDPE (60) wt.% were incorporated into hydroxyapatite (40) wt.% to form biocomposite using hot-presstechniques. These samples were characterized by XRD, Field Emission scanning electron microscope (FESEM), Atomic forcemicroscopy (AFM), mechanical properties with tensile strength and hardness test. Homogeneous, better distribution of thefibrous network and microstructure arrangements were among the most prominent characteristics obtained through XRD,FESEM, and AFM examinations. The result showed improved approximately (3.1 times) compared with pure sample (withoutaddition MWCNT) in the tensile test. Also, the microhardness improves approximate 24% compared to pure samples HA/HDPE. Based on the experimental results, the synthesis HA/ HDPE/MWCNT bio-composites prepared to have excellentcharacteristics that make them suitable application as a substitute material for bone repair.

GeneXpert MTB/RIF Testing in the Management of Patients with Active Tuberculosis; A Real Life Experience from Saudi Arabia

Ali S. Omrani,Mohammed F. Al-Otaibi,Souad M. Al-Ateah,Fahad M. Al-Onazi,Kamran Baig,Noura A. El-Khizzi,Ali M. Albarrak 대한감염학회 2014 Infection and Chemotherapy Vol.46 No.1

Background: GeneXpert MTB/RIF is a real-time PCR assay with established diagnostic performance in pulmonary and extra-pulmonaryforms of tuberculosis. The aim of this study was to assess the contribution of GeneXpert MTB/RIF assay to the management ofpatients with any form of active tuberculosis in a single large tertiary center in Saudi Arabia, with a special focus on the impact ontime to start of antituberculous therapy compared with Ziehl-Neelsen (ZN) smears and mycobacterial cultures. Materials and Methods: Clinical, radiological and laboratory records for all patients who were commenced on antituberculous therapybetween March 2011 and February 2013 were retrospectively reviewed. Results: A total of 140 patients were included, 38.6% of which had pulmonary tuberculosis. GeneXpert MTB/RIF was requested for only39.2% of patients and was the only reason for starting antituberculous therapy for only 12.1%. The median time to a positive GeneXpertMTB/RIF result was 0 days (IQR 3) compared with 0 day (IQR 1) for smear microscopy (P > 0.999) and 22 days (IQR 21) for mycobacterialcultures (P < 0.001). No patients discontinued antituberculous therapy because of a negative GeneXpert MTB/RIF result. Conclusions: In a setting wherein physicians are highly experienced in the diagnosis and treatment of tuberculosis, GeneXpertMTB/RIF was remarkably under-utilized and had only a limited impact on decisions related to starting or stopping antituberculoustherapy. Cost-effectiveness and clinical utility of routine testing of all smear-negative clinical samples submitted for tuberculosisinvestigations by GeneXpert MTB/RIF warrant further study.

Pathogenicity of Bacillus Strains to Cotton Seedlings and Their Effects on Some Biochemical Components of the Infected Seedlings

Aly A. Aly,Omima M. El-Mahdy,Marian M. Habeb,Abeer Elhakem,Amal A. Asran,Maryan M. Youssef,Heba I. Mohamed,Rania S. Hanafy 한국식물병리학회 2022 Plant Pathology Journal Vol.38 No.2

Pathogenicity of eight Bacillus strains to seedlings of four cotton cultivars was evaluated under greenhouse conditions. Each of the tested cultivars was individually treated with powdered inoculum of each bacterial strain. Untreated seeds were planted as control treatments in autoclaved soil. Effects of the tested strains on levels and activities of some biochemical components of the infected seedlings were also assayed. The biochemical components included total soluble sugars, total soluble proteins, total free amino acids, peroxidase, polyphenol oxidase, phenols, and lipid peroxidation. ANOVA showed that Bacillus strain (B) was a very highly significant source of variation in damping-off and dry weight. Cotton cultivar (V) was a nonsignificant source of variation in damping-off while it was a significant source of variation in dry weight. B × V interaction was a significant source of variation in damping- off and a nonsignificant source of variation in dry weight. Bacillus strain was the most important source of variation as it accounted for 59.36 and 64.99% of the explained (model) variation in damping-off and dry weight, respectively. The lack of significant correlation between levels and activities of the assayed biochemical components and incidence of damping-off clearly demonstrated that these biochemical components were not involved in the pathogenicity of the tested strains. Therefore, it was hypothesized that the pathogenicity of the tested strains could be due to the effect of cell wall degrading enzymes of pathogenic toxins. Based on the results of the present study, Bacillus strains should be considered in studying the etiology of cotton seedling damping-off.

A Hybrid Control Approach for Precise Positioning of a Piezo-Actuated Stage

M. Nafea,S. Kazi,Z. Mohamed,M. S. Mohamed Ali 제어로봇시스템학회 2014 제어로봇시스템학회 국제학술대회 논문집 Vol.2014 No.10

Piezo-actuated stages are composed of a piezoelectric actuator (PEA) and a positioning mechanism. Hysteresis behavior of PEAs limits the position accuracy of the piezo-actuated stages. This paper presents a hybrid control approach for precise positioning of a piezo-actuated stage, where Bouc-Wen hysteresis model is used to represent the hysteresis behavior of the PEA. A Luenberger observer-based feedforward controller is designed, and then integrated with a Particle Swarm Optimization (PSO)-based Proportional-Integral-Derivative (PID) controller to form a hybrid controller. Optimal PID gains are obtained based on a fitness function proposed to reduce the displacement error and achieve fast response time. The results show that using the proposed hybrid controller reduces the hysteresis effect significantly, and thus the maximum error is minimized to 0.127 μm, which is 0.17 % of the maximum displacement of 72.1 μm.

Assessing Behaviour of Fresh and Hardened Geopolymer Concrete Mixed with Class-F Fly Ash

M. Albitar,P. Visintin,M.S. Mohamed Ali,M. Drechsler 대한토목학회 2015 KSCE JOURNAL OF CIVIL ENGINEERING Vol.19 No.5

Geopolymer binders have been shown to be a potential green replacement for Ordinary Portland Cement (OPC) in concrete manufacture. This paper presents an experimental study into the behaviour of geopolymer concrete in both its wet and hardened states using Class F fly ash. The experimental program included 15 mix designs to investigate the influence of water-to-binder and superplasticiser-to-binder ratios on the workability and strength of fly ash-based geopolymer concrete. The results show that the addition of naphthalene sulphonate polymer-based superplasticiser has little to no influence on workability and a detrimental effect on strength. Furthermore, the indirect tensile strength, flexural tensile strength and elastic modulus of fly ash-based geopolymer concrete were recorded in this experimental program and have been added to a database of available tests in the open literature. The experimentally determined results are subsequently compared with prediction models developed for OPC-based concrete. The comparison suggests that existing OPC models provide reasonably accurate predictions of the elastic moduli and stress-strain relationships, whereas they slightly underestimate flexural and splitting tensile strengths