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      • KCI등재

        Low-Voltage CMOS Current Feedback Operational Amplifier and Its Application

        Soliman A. Mahmoud,Ahmed H. Madian,Ahmed M. Soliman 한국전자통신연구원 2007 ETRI Journal Vol.29 No.2

        A novel low-voltage CMOS current feedback operational amplifier (CFOA) is presented. This realization nearly allows rail-to-rail input/output operations. Also, it provides high driving current capabilities. The CFOA operates at supply voltages of ±0.75 V with a total standby current of 304 μA. The circuit exhibits a bandwidth better than 120 MHz and a current drive capability of ±1 mA. An application of the CFOA to realize a new all-pass filter is given. PSpice simulation results using 0.25 μm CMOS technology parameters for the proposed CFOA and its application are given.

      • SCOPUSKCI등재
      • SCIESCOPUS

        Nonlinear transient analysis of FG pipe subjected to internal pressure and unsteady temperature in a natural gas facility

        Soliman, Ahmed E.,Eltaher, Mohamed A.,Attia, Mohamed A.,Alshorbagy, Amal E. Techno-Press 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.66 No.1

        This study investigates the response of functionally graded (FG) gas pipe under unsteady internal pressure and temperature. The pipe is proposed to be manufactured from FGMs rather than custom carbon steel, to reduce the erosion, corrosion, pressure surge and temperature variation effects caused by conveying of gases. The distribution of material graduations are obeying power and sigmoidal functions varying with the pipe thickness. The sigmoidal distribution is proposed for the 1st time in analysis of FG pipe structure. A Two-dimensional (2D) plane strain problem is proposed to model the pipe cross-section. The Fourier law is applied to describe the heat flux and temperature variation through the pipe thickness. The time variation of internal pressure is described by using exponential-harmonic function. The proposed problem is solved numerically by a two-dimensional (2D) plane strain finite element ABAQUS software. Nine-node isoparametric element is selected. The proposed model is verified with published results. The effects of material graduation, material function, temperature and internal pressures on the response of FG gas pipe are investigated. The coupled temperature and displacement FEM solution is used to find a solution for the stress displacement and temperature fields simultaneously because the thermal and mechanical solutions affected greatly by each other. The obtained results present the applicability of alternative FGM materials rather than classical A106Gr.B steel. According to proposed model and numerical results, the FGM pipe is more effective in natural gas application, especially in eliminating the corrosion, erosion and reduction of stresses.

      • Inflammation, Oxidative Stress and L-Fucose as Indispensable Participants in Schistosomiasis-Associated Colonic Dysplasia

        Soliman, Nema Ali,Keshk, Walaa Arafa,Shoheib, Zeinab Salah,Ashour, Dalia Salah,Shamloula, Maha Moustafa Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.3

        Background: Schistosomiasis is a parasitic disease causing chronic ill health in humans with a serious consequences for socio-economic development in tropical and subtropical regions. There is also evidence linking Schistosoma mansoni to colonic carcinoma occurrence. The aim of this study was to evaluate some inflammatory and oxidative stress biomarkers, as well as L-fucose as linkers between intestinal schistosomiasis and colonic dysplasia development in mice. Materials and Methods: This study was conducted upon 80 mice that were divided the control group (10 non infected mice) and infected group which was subdivided into 7 sub-groups (10 mice each) according to the time of sacrifaction in the post infection (p.i.) period, 10 mice being sacrificed every two weeks from 6 weeks p.i. to 18 weeks p.i. Tumor necrosis factor alpha (TNF-${\alpha}$), inducible nitric oxide synthase (iNOS), and pentraxin 3 (PTX3) levels were estimated by immunoassay. The L-fucose level, and thioredoxin reductase (TrxR) and lactate dehydrogenase (LDH) activities were also evaluated in colonic tissue. Results: The current study revealed statistically significant elevation in the studied biochemical markers especially at 16 and 18 weeks p.i. The results were confirmed by histopathological examination that revealed atypical architectural and cytological changes in the form of epithelial surface serration and nuclear hyper-chromatizia at 14, 16 and 18 weeks p.i. Conclusions: inflammation, oxidative stress and L-fucose together may form an important link between Schistosomal mansoni infection and colonic dysplasia and they can be new tools for prediction of colonic dysplasia development in experimental schistosomiasis.

      • KCI등재

        New Fully-Differential CMOS Second-Generation Current Conveyer

        Soliman awad Mahmoud 한국전자통신연구원 2006 ETRI Journal Vol.28 No.4

        This paper presents a new CMOS fully-differential second-generation current conveyor (FDCCII). The proposed FDCCII is based on a fully-differential difference transconductor as an input stage and two class AB output stages. Besides the proposed FDCCII circuit operating at a supply voltage of ± 1.5 V, it has a total standby current of 380 μA. The applications of the FDCCII to realize a variable gain amplifier, fullydifferential integrator, and fully-differential second-order bandpass filter are given. The proposed FDCII and its applications are simulated using CMOS 0.35 μm technology.

      • SCOPUSKCI등재

        Synthesis of Some New 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone Derivatives

        Soliman, Mohamed H. A.,El-Sakka, Sahar S. Korean Chemical Society 2011 대한화학회지 Vol.55 No.2

        4,5-Dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone derivative계 화합물의 합성연구를 수행하였다. 첫 번째로, 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone (1)은 o-cresyl methyl ether와 succinic anhydride를 Friedel-Crafts 아실화 반응을 통하여 얻은 다음에, 고리화 반응을 통하여 합성하였다. 얻어진 화합물 1을, NaOEt조건 하에서, 방향족 알데히드와 반응시켜서 4-substituted benzyl pyridazinones (3a-d)을 합성하였으며, 화합물 1을 탈수소화반응을 시켜서 화합물 4를 얻었다. 한편 pyridazine 5는 화합물 1과 1,3-diphenyl-2-propen-1-one을 Michael 첨가반응을 이용하여 합성하였다. N-Dialkylaminomethyl 화합물 6a-b는 pyridazinone 1과 formaldehyde 및 2차 amine을 바능시켜서 얻은 반면에, 화합물 7은 pyridazinone 1을 반응시켜서 얻었으며, 화합물 8은 pyridazinone 3b를 phosphorus oxychloride 와 반응시켜서 얻었다. The present study describes the synthesis of 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone derivatives. The synthesis of the first target compound, 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone (1), was achieved by Friedel-Crafts acylation of o-cresyl methyl ether with succinic anhydride and subsequent cyclization of the intermediary g-keto acid with hydrazine hydrate. Condensation of compound 1 with aromatic aldehydes in the presence of sodium ethoxide affords the corresponding 4-substituted benzyl pyridazinones (3a-d). The dihydropyridazinone 1 underwent dehydrogenation upon treatment with bromine/acetic acid mixture to give (4). Pyridazine (5) has been synthesized upon the reaction of pyridazinone (1) with 1,3-diphenyl-2-propen-1-one under the Michael addition reaction. N-dialkylaminomethyl derivatives 6a-b have been obtained from the reaction of pyridazinone 1 with formaldehyde and secondary amine, whereas reaction of 1 with formaldehyde gives N-hydroxymethyl derivative (7). This study also includes the synthesis of the 3-chloropyridazine derivative 8 in excellent yield by heating pyridazinone 3b in phosphorus oxychloride. The behaviour of the chloro derivative toward sodium azide, benzyl amine and anthranilic acid was also studied. The proposed structures of the products were confirmed by elemental analysis, spectral data and chemical evidence.

      • KCI등재
      • Activation of PI3K, Akt, and ERK during early rotavirus infection leads to V-ATPase-dependent endosomal acidification required for uncoating

        Soliman, Mahmoud,Seo, Ja-Young,Kim, Deok-Song,Kim, Ji-Yun,Park, Jun-Gyu,Alfajaro, Mia Madel,Baek, Yeong-Bin,Cho, Eun-Hyo,Kwon, Joseph,Choi, Jong-Soon,Kang, Mun-Il,Park, Sang-Ik,Cho, Kyoung-Oh Public Library of Science 2018 PLoS pathogens Vol.14 No.1

        <▼1><P>The cellular PI3K/Akt and/or MEK/ERK signaling pathways mediate the entry process or endosomal acidification during infection of many viruses. However, their roles in the early infection events of group A rotaviruses (RVAs) have remained elusive. Here, we show that late-penetration (L-P) human DS<I>-</I>1 and bovine NCDV RVA strains stimulate these signaling pathways very early in the infection. Inhibition of both signaling pathways significantly reduced production of viral progeny due to blockage of virus particles in the late endosome, indicating that neither of the two signaling pathways is involved in virus trafficking. However, immunoprecipitation assays using antibodies specific for pPI3K, pAkt, pERK and the subunit E of the V-ATPase co-immunoprecipitated the V-ATPase in complex with pPI3K, pAkt, and pERK. Moreover, Duolink proximity ligation assay revealed direct association of the subunit E of the V-ATPase with the molecules pPI3K, pAkt, and pERK, indicating that both signaling pathways are involved in V-ATPase-dependent endosomal acidification. Acidic replenishment of the medium restored uncoating of the RVA strains in cells pretreated with inhibitors specific for both signaling pathways, confirming the above results. Isolated components of the outer capsid proteins, expressed as VP4-VP8* and VP4-VP5* domains, and VP7, activated the PI3K/Akt and MEK/ERK pathways. Furthermore, psoralen-UV-inactivated RVA and CsCl-purified RVA triple-layered particles triggered activation of the PI3K/Akt and MEK/ERK pathways, confirming the above results. Our data demonstrate that multistep binding of outer capsid proteins of L-P RVA strains with cell surface receptors phosphorylates PI3K, Akt, and ERK, which in turn directly interact with the subunit E of the V-ATPase to acidify the late endosome for uncoating of RVAs. This study provides a better understanding of the RVA<I>-</I>host interaction during viral uncoating, which is of importance for the development of strategies aiming at controlling or preventing RVA infections.</P></▼1><▼2><P><B>Author summary</B></P><P>Viral particles must transport their genome into the cytoplasm or the nucleus of host cells to initiate successful infection. Knowledge of how viruses may pirate host cell signaling cascades or molecules to promote their own replication can facilitate the development of antiviral drugs. Group A rotavirus (RVA) is a major etiological agent of acute gastroenteritis in young children and the young of various mammals. RVA enters cells by a complex multistep process. However, the cellular signaling cascades or molecules that facilitate these processes are incompletely understood. Here, we demonstrate that infection with late-penetration RVA strains results in phosphorylation of PI3K, Akt, and ERK signaling molecules at an early stage of infection, a process mediated by the multistep binding of RVAs outer capsid proteins. Specific inhibitors for PI3K/Akt and MEK/ERK signaling pathways trap the viral particles in late endosome, and acidic replenishment restores and releases them. Moreover, the RVA-induced phosphorylated PI3K, Akt, and ERK directly interact with the subunit E of the V-ATPase proton pump, required for endosomal acidification and RVA uncoating. Understanding how RVA-induced early activation of cellular signaling molecules mediates the V-ATPase-dependent endosomal acidification required for uncoating of viral particles opens up opportunities for targeted interventions against rotavirus entry.</P></▼2>

      • Brain correlates to facial motor imagery and its somatotopy in the primary motor cortex

        Soliman, Ramy S.,Lee, Sanghoon,Eun, Seulgi,Mohamed, Abdalla Z.,Lee, Jeungchan,Lee, Eunyoung,Makary, Meena M.,Kathy Lee, Seung Min,Lee, Hwa-Jin,Choi, Woo Suk,Park, Kyungmo Wolters Kluwer Health | Lippincott Williams Wilkin 2017 NEUROREPORT - Vol.28 No.5

        <P>Motor imagery (MI) has attracted increased interest for motor rehabilitation as many studies have shown that MI shares the same neural networks as motor execution (ME). Nevertheless, MI in terms of facial movement has not been studied extensively; thus, in the present study, we investigated shared neural networks between facial motor imagery (FMI) and facial motor execution (FME). In addition, FMI somatotopy within-face was investigated between the forehead and the mouth. Functional MRI was used to examine 34 healthy individuals with ME and MI paradigms for the forehead and the mouth. The general linear model and a paired t-test were performed to define the facial area in the primary motor cortex (M1) and this area has been used to investigate somatotopy between the forehead and mouth FMI. FMI recruited similar brain motor areas as FME, but showed less neural activity in all activated regions. The facial areas in M1 were distinguishable from other body movements such as finger movement. Further investigation of this area showed that forehead and mouth imagery tended to lack a somatotopic representation for position on M1, and yet had distinct characteristics in terms of neural activity level. FMI showed different characteristics from general MI as the former exclusively activated facial processing areas. In addition, FME and FMI showed different characteristics in terms of BOLD signal level, while sharing the same neural areas. The results imply a potential usefulness of MI training for rehabilitation of facial motor disease considering that forehead and mouth somatotopy showed no clear position difference, and yet showed a significant BOLD signal intensity variation. NeuroReport 28: 285-291 Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.</P>

      • Diagnostic and Prognostic Relevance of Bone Marrow Microenvironment Components in Non Hodgkin's Lymphoma Cases Before and After Therapy

        Soliman, Amira H Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.12

        Objective: To evaluate stromal cells of the bone marrow microenvironment (BMM) in bone marrow trephine biopsy (BMTB) specimens, with a focus on fibronectin, tumor necrosis factor- alpha (TNF-${\alpha}$) and L-selectin in Non-Hodgkin's lymphoma (NHL) patients, before and after therapy. Materials and Methods: A total of 80 de novo NHL patients, 64 with B-cell lymphomas 80%, (follicular cell lymphoma (FCL) in 32, chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) in 12, and diffuse large cell lymphoma in 20) and 16 with T-cell lymphomas (20%) all diagnosed as T-Lymphoblastic lymphomas, were evaluated before and after therapy. For comparison, 25 age and sex matched BM donors, were included as a control group. BMTB material and BM aspirates were taken for morphological assessment of stromal cells, the plasma of these samples being examined for $TNF{\alpha}$ and L-selectin by ELISA, and fibronectin by radial immunodiffusion (RID). Results: BM stromal cells comprising reticular macrophages and fibroblasts were elevated in 53.3% of NHL cases at diagnosis, while BM fibronectin levels were decreased and BM $TNF{\alpha}$ and L-selectin were higher than in controls (p<0.05). In NHL cases, elevated values of BM $TNF{\alpha}$ and BM L-selectin were associated with signs of aggressive disease, including >1 extra nodal sites, detectable B symptoms, high grade, BM and CNS invasion, and a high International prognostic index (IPI) (p<0.05). Conclusion: BMM components, $TNF{\alpha}$, L-selectin and fibronectin, in NHL can be useful in evaluating disease activity, extent and response to treatment and as prognostic markers according to the IPI.

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