Effect of Metal Precipitation on the Chemical Composition of Pectins

Jaekwan Hwang,Tarik H. Roshdy,Jozef L. Kohini 한국식품과학회 1992 Food Science and Biotechnology Vol.1 No.2

Effect of Laser Beam on Structural, Optical, and Electrical Properties of BaTiO₃ Nanoparticles during Sol-Gel Preparation

Mostafa, Massaud,Ebnalwaled, Khaled,Saied, Hussien A.,Roshdy, Reham The Korean Ceramic Society 2018 한국세라믹학회지 Vol.55 No.6

This work concentrated on the effect of different laser beams on the microstructure and dielectric properties of $BaTiO_3$ nanoparticles at different calcinations times during the gelling preparation step. The nanoparticles were prepared by the sol-gel method. A green (1000 mW, 532 nm) and red laser beam (500 mW, 808 nm), were applied vertically at the center of stirring raw materials. The samples were sintered at $1000^{\circ}C$ for 2, 4, and 6 h. X-ray diffraction (XRD) analysis showed that samples prepared under the green laser have the highest purity. The FT-IR spectra showed that the stretching and bending vibrations of TiO bond without any other bonds, which are compatible to the X-ray diffraction (XRD) results. Samples were characterized by transmission electron microscopy (TEM), Scan electron microscopy (SEM), and UV-Visible spectrophotometer. Characterization showed the samples prepared under the green laser to have the highest particle size (~ 50 nm) and transparency for all sintering durations. Laser beam effects on electrical characterization were studied. BT nanoparticles prepared under the green laser show the higher dielectric constant, which was found to increase with sintering temperature.

Alternatives to Enhance Flat Slab Ductility

Mohamed Husain,Ahmed S. Eisa,Ramy Roshdy 한국콘크리트학회 2017 International Journal of Concrete Structures and M Vol.11 No.1

Flat slab systems are vastly used in multi-story buildings because of their savings in story height and construction time, as well as for their flexibility in architectural remodeling. However, they frequently suffer brittle punching-shear failure around columns, especially when subjected to lateral loads. Therefore, seismic codes labeled flat slabs as non-ductile systems. This research goal is investigating some construction alternatives to enhance flat slab ductility and deformability. The alternatives are: adding different types of punching-shear reinforcement, using discreet fibers in concrete mixes, and increasing thickness of slab around columns. The experimental study included preparation and testing of seven half-scale interior slab-column connections up to failure. The first specimen is considered a reference, the second two specimens made of concrete mixes with different volumetric ratios of polymer fibers. Another three specimens reinforced with different types of punching-shear reinforcement, and the last specimen constructed with drop panel of inverted pyramidal shape. It is found that using the inverted pyramid-shape drop panel of specimen, increases the punching-shear capacity, and the initial and the post-cracking stiffnesses. The initial elastic stiffnesses are different for all specimens especially for the slab with closed stirrups where it is experienced the highest initial stiffness compared to the reference slab.

Darcy-Forchheimer Flow of Magnetized Bioconvective Williamson Nanofluid with Variable Thermal Conductivity

Fazal Haq,Muzher Saleem,Essam Roshdy El-Zahar,Soumaya Gouadria,M. Ijaz Khan 한국자기학회 2021 Journal of Magnetics Vol.26 No.4

In this article modeling and theoretical analysis of magnetized Williamson nanomaterial flow by permeable surface of cylinder is studied. The idea of self-propelled gyrotactic microorganisms is implemented to stabilize the suspended nanoparticles in Williamson liquid. Darcy-Forchheimer together with porosity effects are accounted in the flow. Energy relation is modeled in view of thermal radiation, variable thermal conductivity and Joule heating. Activation energy linked with chemical reaction is executed at the surface. Furthermore, Brownian dispersion and thermophoresis effects are also considered. Flow governing dimensional model is acquired using boundary layer suppositions. Suitable transformations are used to alter the system of PDE’s into non-dimensional. NDSolve code in Mathematica package is utilized to solve the model. Impacts of various flow regulating variables on velocity, temperature, mass concentration and motile density are investigated by plotting. Coefficient of skin friction, Sherwood number, motile density number and heat transfer rate are tabulated and analyzed. It is observed that velocity field decays while temperature field enhances versus rising dimensionless magnetic parameter. Moreover, due to magnetic field more Lorentz force is applied to the flow as a result surface drag force enhances while heat transfer rate decays.

Alternatives to Enhance Flat Slab Ductility

Husain, Mohamed,Eisa, Ahmed S.,Roshdy, Ramy Korea Concrete Institute 2017 International Journal of Concrete Structures and M Vol.11 No.1

Flat slab systems are vastly used in multi-story buildings because of their savings in story height and construction time, as well as for their flexibility in architectural remodeling. However, they frequently suffer brittle punching-shear failure around columns, especially when subjected to lateral loads. Therefore, seismic codes labeled flat slabs as non-ductile systems. This research goal is investigating some construction alternatives to enhance flat slab ductility and deformability. The alternatives are: adding different types of punching-shear reinforcement, using discreet fibers in concrete mixes, and increasing thickness of slab around columns. The experimental study included preparation and testing of seven half-scale interior slab-column connections up to failure. The first specimen is considered a reference, the second two specimens made of concrete mixes with different volumetric ratios of polymer fibers. Another three specimens reinforced with different types of punching-shear reinforcement, and the last specimen constructed with drop panel of inverted pyramidal shape. It is found that using the inverted pyramid-shape drop panel of specimen, increases the punching-shear capacity, and the initial and the post-cracking stiffnesses. The initial elastic stiffnesses are different for all specimens especially for the slab with closed stirrups where it is experienced the highest initial stiffness compared to the reference slab.

Early and Late Functional Outcomes of Anal Sphincter-Sparing Procedures With Total Mesorectal Excision for Anorectal Adenocarcinoma

Osama Eldamshety,Sherif Kotb,Ashraf Khater,Waleed Elnahas,Sameh Roshdy,Mohamed S. Zahi,Hend M.H. Rashed Elkalla,Omar Farouk,Ahmed Senbel,Adel Fathi,Emad-Eldeen Hamed,Khaled Abdelwahab,Islam A. Elzahby 대한대장항문학회 2020 Annals of Coloproctolgy Vol.36 No.3

Purpose: The study aims to assess the functional outcome of anal sphincter-sparing procedures (SSP) with total mesorectal excision (TME) for anorectal adenocarcinoma. Methods: In a multicentric, prospective, single-group study in the period between December 2012 and November 2017, 93 patients presented with anorectal adenocarcinoma were included in the study. Sixty-nine patients underwent SSP with TME. SSP included the combined approach of transabdominal TME with intersphincteric resection (ISR) or transanal transabdominal TME. Using the per anal examination scoring system (PASS), postoperative anal function was assessed after 1 year. Results: Bowel motility time was 50±19 hours. The time needed for narcotic analgesia was 54±18.8 hours. Mean hospital stay was 15.4±10.25 days. Incidence of evident fecal incontinence after ISR is 10.6% (7 of 67 cases). The PASS findings of 69 cases are as follows: extremely hypotonic 8.6% (6 cases), slightly hypotonic 26.1% (18 cases), normal tone 58% (40 cases), slightly stenotic 3 cases (4.3%), or occluded 2.9% (2 cases). Urinary dysfunction occurred in 1 case (1.4%). Temporary diversion was performed in 61 patients (87.1%). Conclusion: Sphincter preservation with TME for anorectal adenocarcinoma helps avoid permanent stoma and provides reasonable functional outcomes. PASS is a new application for postoperative assessment of anal function.

Analysis of FHIT Gene Methylation in Egyptian Breast Cancer Women: Association with Clinicopathological Features

Zaki, Seham Mahrous,Abdel-Azeez, Hala A.,El Nagar, Mona Roshdy,Metwally, Khaled Abdel-Aziz,Ahmed, Marwa M. Samir S. Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.3

Background: Fragile histidine triad (FHIT) gene is a tumor suppressor gene which involved in breast cancer pathogenesis. Epigenetics alterations in FHIT contributes to tumorigenesis of breast cancer. Objective: Our objective was to study FHIT promoter region hypermethylation in Egyptian breast cancer patients and its association with clinicopathological features. Materials and Methods: Methylation-specific polymerase chain reaction was performed to study the hypermethylation of FHIT promoter region in 20 benign breast tissues and 30 breast cancer tissues. Results: The frequency of hypermethylation of FHIT promoter region was significantly increased in breast cancer patients compared to bengin breast disease patients. The Odd's ratio (95%CI) of development of breast cancer in individuals with FHIT promoter hypermethylation (MM) was 11.0 (1.22-250.8). There were also significant associations between FHIT promoter hypermethylation and estrogen, progesterone receptors negativity, tumor stage and nodal involvment in breast cancer pateints. Conclusions: Our results support an association between FHIT promotor hypermethylation and development of breast cancer in Egyptian breast cancer patients. FHIT promoter hypermethylation is associated with some poor prognostic features of breast cancer.

Surface, thermodynamic and biological activities of some synthesized Gemini quaternary ammonium salts based on polyethylene glycol

AHMED SALAH MAHMOUD TAWFIK,Ali A. Abd-Elaal,새미사반,A.A. Roshdy 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.30 No.-

Quaternary ammonium salts are frequently used as antimicrobial agents that disrupt cell membranethrough the binding of their ammonium cations to anionic sites in the outer tissue of bacteria. This articledescribes the synthesis of Gemini quaternary ammonium salts (G600Br, G1000Br and G1500Br). Thechemical structures of synthesized Gemini quaternary ammonium salts were confirmed using FT-IR and1HNMR spectra. The surface activity of the synthesized surfactants were determined from the surfaceand interfacial tension measurements. The surface parameter including: the critical micelleconcentration (CMC), effectiveness (pcmc), efficiency (Pc20), maximum surface excess (Gmax) andminimum surface area (Amin), were calculated from the surface tension measurements, also, the foamingand emulsification power were measured. The thermodynamic parameters of micellization andadsorption showed their tendency towards adsorption at the interfaces and also micellization in the bulkof their solutions. Screening tests of the synthesized compounds showed that the compounds exhibit aneffective antimicrobial activity on a variety of bacteria including Gram-positive bacteria (Bacillus subtilisand Micrococcus luteus), Gram-negative bacteria (Bordetella pertussis and Escherichia coli) and Fungi(Candida albicans and Aspergillus niger).

Analysis of fourth-grade fluid model over a stretchable surface with Riga plate subject to permeable medium

Hua Bian,Shah Faisal,Khan M Ijaz,El-Zahar Essam Roshdy,Farooq Shahid,Khan Sami Ullah,Guedri Kamel,Wu Wen-jing 한국CDE학회 2022 Journal of computational design and engineering Vol.9 No.3

The current investigation is concerned with the rheological impact of fourth-grade confined by Riga surface. The flow behaviour is analysed over a Riga plate in the presence of stagnation point and porous medium. The relevant similarity variables and corresponding boundary conditions are adopted to model the current problem. The highly non-linear coupled differential system is via optimal homotopy scheme. The outcomes of relevant dimensionless parameters on the velocity profile have been visualized with physical exploration. It is observed from the obtained outcomes that the fluid velocity declines against rising estimations of modified magnetic variable and inverse Darcy number. The increasing velocity change is noted for boosting values of third-grade fluid parameter. Moreover, the velocity pattern for fourth-grade material is comparatively higher than viscous, second-grade, and third-grade materials. The comparative analysis against obtained simulations is also listed.

Soluble Suppression of Tumorigenicity-2 as a Candidate Prognostic Marker for Stroke: A Systematic Review

Ahmadzadeh Koohyar,Dizaji Shayan Roshdi,Balabandian Mohammad,Ramawad Hamzah Adel,Yousefifard Mahmoud 대한진단검사의학회 2023 Annals of Laboratory Medicine Vol.43 No.6

Background: Risk stratification of patients for incidence of stroke and its outcomes can aid in decision-making regarding treatment options and rehabilitative care. We systematically reviewed the literature to provide comprehensive evidence for the value of serum soluble suppression of tumorigenicity-2 (sST-2) in the prediction of stroke incidence and the evaluation of post-stroke outcomes. Methods: The Medline, Scopus, Web of Science, and Embase databases were searched until the end of August 2022 for studies investigating the value of serum sST-2 in the prediction of stroke incidence and post-stroke outcomes. Results: Nineteen articles were included. The articles reported conflicting results on the predictive value of sST-2 measurement in the incidence of stroke. Studies investigating the value of sST-2 measurement for the prognosis of post-stroke outcomes have reported positive associations between sST-2 levels and post-stroke mortality, composite adverse events, major disability, cerebral–cardiac syndrome, and cognitive impairment. Conclusions: Although some studies have reported a predictive value of serum sST-2 measurement in the incidence of stroke, a clear consensus has yet to be reached because of discrepancies in the results. As for the prognosis of post-stroke outcomes, sST-2 may be a predictor of mortality, composite adverse events, and major disability after stroke. Overall, more well-designed prospective cohort studies are needed to reach a more decisive conclusion on the value of sST-2 measurement for the prediction of stroke and its outcomes and to determine optimal cutoffs.