Osiris W. Guirguis

Cairo University | CU · Department of Biophysics

In this paper, treated Saudi cotton fabrics were prepared by dipping them in chitosan and chitosan/ZnO-NPs solutions of four different concentrations (10, 20, 30, and 40 wt% ZnO-NPs). The chemical compositions, optical properties, mechanical characteristics, and air permeability of the prepared fabrics after immersion were investigated. The tristim...

The goal of this study is to improve the qualities of Saudi cotton fabrics to be used in a variety of industrial and medicinal applications. Cotton fabrics were treated by dipping in chitosan/ZnO-NPs solutions with various ZnO-NPs concentrations. XRD and SEM of crystal and morphological structure, thermal analysis (TG and DSC) of fabric stability f...

Objective: To evaluate dose differences predicted between using Anisotropic Analytical Algorithm (AAA) and Acuros XB (AXB) in patients diagnosed with locally advanced non-small cell lung cancer (NSCLC) treated with intensity modulated radiation therapy (IMRT). Methods: A phantom study was done to evaluate the dose prediction accuracy of AXB and...

The solution casting method was used to prepare nanocomposite films of chitosan/TiO2 nanoparticles (NPs) because of their applications in various fields. The effects of TiO2NP concentration on the structural, morphological, thermal, mechanical, and optical properties of such films were studied by X-ray diffraction (XRD), high-resolution transmissio...

In this study, we have investigated the effect of adding zinc chloride (ZnCl 2 ) on polycaprolactone (PCL) before and after electrospinning. The rheological properties and conductivity of ZnCl 2 /PCL solutions were measured prior to the electrospinning process. The resultant electrospun mats were characterized by SEM, contact angle, FTIR, XRD, mech...

Photodetector application of organic-based device like porphine palladium (II) substitution, 5,10,15,20-Tetrakis (pentafluorophenyl)-21H,23H-porphine palladium (II), (TPPFT) thin films was investigated. A high quality and adherent films over various substrates were prepared using a low-cost spin coating method. The HR-TEM images confirm the nanofib...

Transformation process of TiO 2 from anatase to rutile phase upon annealing affects its optical and biological implications. In the present work; TiO 2 is synthesized by sol-gel technique. The optical and biological implications were depicted through the transformation process covering the range of 350-800 • C. Raman spectroscopy applied for depict...

The aim of the present study was to prepare and characterize nanocomposite films to improve the treatment of skin wounds by applying the film as a bandage. To modify chitosan (Cs) and to prepare nanocomposites, a mixture between titanium dioxide nanoparticles (TiO2NPs) was performed at different concentrations (2, 5, 10 and 15 wt%) and oleic acid (...

In the present work, cotton fabrics were dyed with natural dye extracted from the barks of a plant named Calligonum comosum. The dyed fabrics were mordanting with four mordants (potassium aluminium sulphate, black eco-crumb, ferrous chloride, and ferrous sulphate) applied separately. The effect of the mordants was described by XRD, FT-IR, SEM, DSC...

In the present study, composites of hydroxypropyl cellulose and iron (III) oxide nanoparticles (HPC:Fe2O3 NPs) were prepared in different ratios (20:0.5, 20:1, 20:1.5 and 20:2 wt:wt). Variations in the group coordination of the prepared composites in the IR region were employed. The reflectance spectra in the visible region (400–700 nm) were follow...

Electrospun polycaprolactone is widely used in the medical field. Formic acid/acetic acid (FA/AA) solvent system is one of the safest solvents used for the production of nano-range polycaprolactone (PCL) fibers, although it has a very low stability. In the present study, the stability of PCL in FA/AA system was enhanced by sodium hydrogen carbonate...

In the present investigation, a variety of strong and weak acids have been chosen for the bone decalcification process. Demineralization of dog cranial bone was carried out using 0.6 M concentration of either hydrochloric, lactic or citric acid. Optical characterization such as: reflectance spectra, tristimulus values and color parameters were empl...

In the present study, a novel eco-friendly production of silk fabrics dyed with different natural dye bath concentrations (40, 80, 120, 160, 200 and 240 g/l) extracted from neem (Azadirachta indica) leaves was developed. The surface morphology of the fabrics was examined by scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) sp...

THE placesPRESENT in advancedwork research.focused Theon modifying effect of UV-ozonethe chitosan irradiationstructure withwhich differenthas noticeable exposure doses (9.68 x 10⁻¹⁴, 19.35 x 10⁻¹⁴, 29.03 x 10⁻¹⁴ and 38.75 x 10⁻¹⁴ J/m²) on the microstructural, thermal stability and optical properties of chitosan was studied. X-ray diffraction (XRD),...

Electrospun nano-polycaprolactone (PCL) is an ideal candidate for biomedical applications, as it mimics the extracellular matrix and possesses good biocompatibility, biodegradability and mechanical properties. Formic acid/acetic acid (FA/AA) and formic acid/acetone (FA/A) solvent systems were reported to be the safest solvents for the preparation o...

The aim of the work was to evaluate the effect of ultraviolet-ozone (UV-O3) irradiation with different times on the structure and thermal properties of hydroxypropyl methylcellulose (HPMC) in the form of a thin film to be used as bioequivalent materials according to their important broad practical and medical applications. HPMC thin films were expo...

Blends of PVA/HPMC of different mass percents are prepared using solution casting method and are subjected to fast neutron irradiation of fluence 1 × 107 n cm−2. Structural configuration of the blends as well as thermal properties is studied using X-ray diffraction (XRD) and thermal analyses (differential scanning calorimetry and thermal gravimetri...

Intensity modulated radiotherapy (IMRT) for lower esophageal cancer is challenging to improve tumor coverage and spare normal tissue. This study is performed to investigate the effect of different parameters (beam numbers, directions and local avoid structure optimization) and which of them is the most effective on the dose conformity and homogenei...

In the present work, variation in the group coordination of chitosan due to the exposure to UV/ozone was considered by the FTIR reflectance. Pronounced variations in the intensities of reflectance bands and shifts in their positions were detected. This could be attributed to the change in the molecular configuration of chitosan. On the other hand,...

Contamination by bacterial strands is a major problem after bone replacement surgeries, so there is a great need to develop low cost biocompatible antibacterial bioactive scaffolds to be used in bone tissue engineering. For this purpose, nano-zinc doped hydroxyapatite with different zinc-concentrations (5, 10 and 15 mol%) was successfully prepared...

Intensity modulated radiotherapy (IMRT); Esophageal cancer; Optimum orientation of beams; Normal tissue sparing; Organ at risks. KEYWORDS ABSTRACT The present study is designed to evaluate the feasibility of beam intensity modulation on treatment planning of the mid esophagus to reduce normal lung doses, by comparing different intensity modulated r...

A series of colloidal CdSe quantum dots doped with different concentration of cobalt ions has been prepared via organometallic pyrolysis of a mixture of cadmium stearate and cobalt dithiocarbazate. The conditions required for successful doping depend on the source of cobalt ions and the dopant concentration. The structure and morphology of the prep...

In the present investigation, a variety of strong and weak acids have been chosen for the bone decalcification process. Demineralization of dog cranial bone was carried out using 0.6 M concentration of either hydrochloric, lactic or citric acid. Optical characterization such as: reflectance spectra, tristimulus values and color parameters were empl...

Strong and weak acids were chosen for the bone decalcification process. Demineralization of dog cranial bone was carried out using 0.6 M concentration of either of hydrochloric, lactic or citric acid. Consequent morphologic changes were correlated with the developed chemistry, porosity and structure through XRD and FT-IR of the matrices. The dielec...

The purpose of the present study is to enhance the antimicrobial activity of chitosan. For this reason, thin films of chitosan incorporated with different concentrations of Jojoba liquid wax (JLW) were prepared by using the casting technique. The agar disc diffusion method was used to investigate the antimicrobial activity of the films against two...

This manuscript presents a theoretical analysis of the elastic properties of ZnO−Na2O−Al2O3−B2O3 (in molar %) glass. The elastic moduli were calculated in terms of Makishima–Mackenzie theory and bond compression model. Addition effect of ZnO on the elastic moduli was investigated according to bond compression model in terms of the number of network...

The frequency-dependent dielectric dispersion of ZnO–Na2O–Al2O3–B2O3 (in mol%) glass prepared by the melt quenching technique is investigated in the temperature ranges from room temperature to 420 K. Dielectric relaxation has been analyzed based on the behavior of electric modulus behavior. An analysis of the real and imaginary parts of dielectric...

Polymers and polymeric composites have stea-dily reflected their importance in our daily life. Blending poly(vinyl alcohol) (PVA) with a poten-tially useful natural biopolymers such as hy-droxypropyl cellulose (HPC) seems to be an in-teresting way of preparing a polymeric blends. In the present work, blends of PVA/HPC of com-positions (100/0, 90/10...

Carboxymethyl chitosan, (CMC), and N-lauryl-carboxymethyl chitosan (LCMC), have been prepared as water soluble derivatives of chitosan. These biodegradable chitosan derivatives were characterized and investigated for nuclear imaging and body distribution. They were labeled with 99mTc to use them as targeted delivery to some organs in vivo for nucle...

The proposal in this study was to evaluate the optical properties of different biopolymers films. The materials used were poly(vinyl alcohol) (PVA) and hydroxypropyl methylcellulose (HPMC). PVA/HPMC blends were prepared by casting technique. Variations in the group coordination in the infrared region were followed. The effects of HPMC concentration...

Lactosaminated N-succinyl-chitosan (LNSC), a water-soluble biodegradable derivative of chitosan, was prepared, characterized, and investigated for nuclear imaging and body distribution. The labeling efficiency of LNSC was examined with 99mTc, and the obtained complex was used as liver-targeted delivery system in vivo for nuclear imaging, and its bi...

A newly developed bone equivalent hydroxyapatite was derived from veterinary bone (VHAP). Sections of 1 cm of six rabbit mandibles were equally replaced by this VHAP graft. Radiological studies by X-ray were performed pre-operatively, immediately, and 1, 2 and 3 months post-operatively. The graft host-bone interface was examined periodically by sca...