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El-Naggar Moustafa Y.,El-Assar Samy A.,Abdul-Gawad Sahar M. The Microbiological Society of Korea 2006 The journal of microbiology Vol.44 No.4
Twelve actinomycete strains were isolated from Egyptian soil. The isolated actinomycete strains were then screened with regard to their potential to generate antibiotics. The most potent of the producer strains was selected and identified. The cultural and physiological characteristics of the strain identified. the strain as a member of the genus Streptomyces. The nucleotide sequence of the 16S rRNA gene (1.5kb) of the most potent strain evidenced a 99% similarity with Streptomyces spp. and S. aureofaciens 16S rRNA genes, and the isolated strain was ultimately identified as Streptomyces sp. MAR01. The extraction of the fermentation broth of this strain resulted in the isolation of one major compound, which was active in vitro against gram-positive, gram-negative representatives and Candida albicans. The chemical structure of this bioactive compound was elucidated based on the spectroscopic data obtained from the application of MS, IR, UV, $^1H$ NMR, $^{13}C$ NMR, and elemental analysis techniques. Via comparison to the reference data in the relevant literature and in the database search, this antibiotic, which had a molecular formula of $C_{19}H_{29}NO_2$ and a molecular weight of 303.44, was determined to differ from those produced by this genus as well as the available known antibiotics. Therefore, this antibiotic was designated Meroparamycin.
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El-Hallag, Ibrahim S.,El-Daly, Samy A. Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.4
The titled dye of DBPI gives amplified spontaneous emission (ASE) with maximum at 580 nm upon pumping by nitrogen laser (${\lambda}_{ex}\;=\;337.1\;nm$). The ground state absorption cross section (${\sigma}_A$) and emission cross section (${\sigma}_E$) as well as effective emission cross section(${\sigma}^*_E$) have been determined. The electronic absorption spectra of DBPI were measured in ethanol and tetrahydrofuran at room and low temperature. DBPI displays molecular aggregation in water. The photochemical reactivity of DBPI was also studied in carbon tetrachloride upon irradiation with 525 nm light. The electrochemical investigation of DBPI dye has been carried out using cyclic voltammetry and convolution deconvolution voltammetry combined with digital simulation technique at a platinum electrode in 0.1 mol/L tetrabutyl ammonium perchlorate (TBAP) in two different solvents acetonitrile ($CH_3CN$) and dimethylformamide (DMF). The species were reduced via consumption of two sequential electrons to form radical anion and dianion (EE mechanism). In switching the potential to positive direction, the compound was oxidized by loss of two sequential electrons, which were followed by a fast dimerization and/or aggregation process i.e $EC_{dim1}EC_{dim2}$ mechanism. The electrode reaction pathway and the chemical and electrochemical parameters of the investigated compound were determined using cyclic and convolutive voltammetry. The extracted electrochemical parameters were verified and confirmed via digital simulation method.
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A Cytotoxic Lupeol Fatty Acid Ester and Other Pentacyclic Triterpenes from Salvadora persica Seeds
Samy K. El-Desouky 한국생약학회 2023 Natural Product Sciences Vol.29 No.3
The phytochemical investigation of the ethyl acetate fraction of the methanol seed extract of Salvadora persica resulted in the isolation and identification of five pentacyclic triterpenes (1-5), oleanolic acid (1), ursolic acid (2), β-amyrin (3), β-amyrin acetate (4) and lupeol tricosanoate (5). The structures of these compounds were established by the analysis of their NMR spectroscopic and mass spectrometric data. In the bioactivity assay, compound 5 showed moderate cytotoxic activities against breast cancer cell lines (MCF-7), colon cancer cell lines (HT-29) and hepatocellular carcinoma cell lines (HepG2) with IC50 values of 9.4, 6.85 and 12.74 μg/mL. respectively. In all previous studies, lupeol tricosanoate (5) has been isolated as a mixture of triterpenoid long-chain fatty acid esters and this is the first report of its isolation and characterization as a pure molecule. Moreover, the occurrence of fatty acid ester of triterpene in this plant is of taxonomic importance.
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Mostafa Samy Abbas,Essam Ezzat Abd El-Hakeem,Hossam Esmat Kamel 대한마취통증의학회 2019 Korean Journal of Anesthesiology Vol.72 No.3
Background: Emergence agitation (EA) is a common problem after sevoflurane anesthesia among children. There have been mixed results with control of EA using propofol 1 mg/kg bolus following sevoflurane anesthesia. An infusion of 3 mg/kg of propofol over 3 min following sevoflurane anesthesia has been found to be promising in children undergoing magnetic resonance imaging scans. However, no studies have been conducted during surgical procedures. We aimed to examine the efficacy of transition to propofol for 3 min after cessation of sevoflurane anesthesia in children undergoing inguinal hernia repair. Methods: In this prospective randomized controlled trial, 64 children aged 1–12 years, scheduled for inguinal hernia repair, were randomized to receive either propofol 3 mg/kg over 3 min (propofol group) or no propofol (control group), after the cessation of sevoflurane anesthesia. EA was assessed using the Paediatric Emergence Anesthesia Delirium (PAED) scale and the Watcha scale. Emergence time and the duration of post-anesthesia care unit (PACU) stay were also recorded. Results: The incidence of ED was lower in the propofol group on both the PAED (81.3% vs. 15.6%, P < 0.001) and the Watcha (78.1% vs. 15.6%, P < 0.001) scales. The mean emergence time was 6.37 minutes longer in the propofol group with no significant difference in PACU times. Conclusions: Transition to propofol 3 mg/kg over 3 min following sevoflurane anesthesia reduces the incidence of EA and improves the quality of emergence. Although emergence times were longer, the duration of stay in the PACU was similar with propofol use.
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Mohammad Daher,Sami Abi Farraj,Bassem El Hassan 대한정형외과학회 2023 Clinics in Orthopedic Surgery Vol.15 No.5
The management of scapular fractures can be either conservative or operative, but it is still unclear how to choose the treatment option. Scapular fractures can be classified anatomically into four types: scapular spine, scapular body, and scapular neck where the treatment is conservative most of the time except for certain indications that are specific to each one, and inferior angle of the scapula where the operative treatment yields the best results but conservative treatment can be contemplated in some cases.
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Neuro-based Canonical Transformation of Port Controlled Hamiltonian Systems
Aminuddin Qureshi,Sami El Ferik,Frank L. Lewis 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.12
In the literature of control theory, tracking control of port controlled Hamiltonian systems is generally achieved using canonical transformation. Closed form evaluation of state-feedback for the canonical transformation requires the solution of certain partial differential equations which becomes very difficult for nonlinear systems. This paper presents the application of neural networks for the canonical transformation of port controlled Hamiltonian systems. Instead of solving the partial differential equations, neural networks are used to approximate the closedform state-feedback required for canonical transformation. Ultimate boundedness of the tracking and neural network weight errors is guaranteed. The proposed approach is structure preserving. The application of neural networks is direct and off-line processing of neural networks is not needed. Efficacy of the proposed approach is demonstrated with the examples of a mass-spring system, a two-link robot arm and an Autonomous Underwater Vehicle (AUV).
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Ibrahim S. El-Hallag,Samy A. El-Daly 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.4
The titled dye of DBPI gives amplified spontaneous emission (ASE) with maximum at 580 nm upon pumping by nitrogen laser (λex = 337.1 nm). The ground state absorption cross section (σA) and emission cross section (σE) as well as effective emission cross section(σ*E) have been determined. The electronic absorption spectra of DBPI were measured in ethanol and tetrahydrofuran at room and low temperature. DBPI displays molecular aggregation in water. The photochemical reactivity of DBPI was also studied in carbon tetrachloride upon irradiation with 525 nm light. The electrochemical investigation of DBPI dye has been carried out using cyclic voltammetry and convolution deconvolution voltammetry combined with digital simulation technique at a platinum electrode in 0.1 mol/L tetrabutyl ammonium perchlorate (TBAP) in two different solvents acetonitrile (CH3CN) and dimethylformamide (DMF). The species were reduced via consumption of two sequential electrons to form radical anion and dianion (EE mechanism). In switching the potential to positive direction, the compound was oxidized by loss of two sequential electrons, which were followed by a fast dimerization and/or aggregation process i.e ECdim1ECdim2 mechanism. The electrode reaction pathway and the chemical and electrochemical parameters of the investigated compound were determined using cyclic and convolutive voltammetry. The extracted electrochemical parameters were verified and confirmed via digital simulation method.
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WiFi Sensing System for Monitoring Public Transportation Ridership: A Case Study
류승한,박병규,Samy El-Tawab 대한토목학회 2020 KSCE Journal of Civil Engineering Vol.24 No.10
Public transportation system as an essential mode of travel has been investigated by local governments and transportation agencies to capture passengers’ travel behaviors. Despite their efforts, agencies especially in small to medium sized cities could not afford to collect such behaviors data due to significant costs associated with the data collection system. In this study, we presented a WiFi sensing system which makes such data collection feasible with low-cost devices. We demonstrated the WiFi sensing system’s applicability in estimating passengers’ origin-destination (O/D) travel and passengers’ bus stop waiting times via video validation. In addition, WiFi signal strength was analyzed to further improve accuracy of the system. To this end, sliding window algorithm was adopted to mitigate the randomness of mobile devices’ signals. Our small-scale proof of concept experiment was conducted at four bus stops along the main transit corridor in Charlottesville, Virginia. Results indicated that the system was able to re-identify 91% of bus passengers and passengers bus stop waiting time error was as small as 7 seconds. It is expected that the system can be a viable low-cost Internet of Things (IoT) solution for monitoring public transit system performance.
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