Applied Science Private University

About: Applied Science Private University is a education organization based out in Amman, Jordan. It is known for research contribution in the topics: Population & Catalysis. The organization has 4124 authors who have published 5299 publications receiving 116167 citations.

Determination of Diffusion Coefficient for Alkane Solvent–CO2 Mixtures in Heavy Oil with Consideration of Swelling Effect

Abstract: A generalized methodology has been developed and successfully applied to determine diffusion coefficient of alkane solvent–CO2–heavy oil systems with consideration of swelling effect. Theoretically, a one-dimensional and one-way mass transfer model incorporating the volume translated Peng–Robinson equation of state (PR EOS) has been developed to describe the mass transfer from alkane solvent–CO2 mixture to heavy oil, which accounts for the oil swelling effect resulted from gas dissolution. The heavy oil sample has been characterized as three pseudocomponents, while the binary interaction parameter (BIP) correlations are tuned with the experimentally measured saturation pressures. Both apparent diffusion coefficients for gas mixtures and individual diffusion coefficient of each component of a mixture are determined once the discrepancy between the measured and calculated dynamic swelling factors of heavy oil has been minimized. The volume translated PR EOS with the three characterized pseudocomponents and ...

Graphene-based nanovehicles for photodynamic medical therapy

Abstract: Graphene and its derivatives such as graphene oxide (GO) have been widely explored as promising drug delivery vehicles for improved cancer treatment. In this review, we focus on their applications in photodynamic therapy. The large specific surface area of GO facilitates efficient loading of the photosensitizers and biological molecules via various surface functional groups. By incorporation of targeting ligands or activatable agents responsive to specific biological stimulations, smart nanovehicles are established, enabling tumor-triggering release or tumor-selective accumulation of photosensitizer for effective therapy with minimum side effects. Graphene-based nanosystems have been shown to improve the stability, bioavailability, and photodynamic efficiency of organic photosensitizer molecules. They have also been shown to behave as electron sinks for enhanced visible-light photodynamic activities. Owing to its intrinsic near infrared absorption properties, GO can be designed to combine both photodynamic and photothermal hyperthermia for optimum therapeutic efficiency. Critical issues and future aspects of photodynamic therapy research are addressed in this review.

Stable Chitosan-Based Nanoparticles Using Polyphosphoric Acid or Hexametaphosphate for Tandem Ionotropic/Covalent Crosslinking and Subsequent Investigation as Novel Vehicles for Drug Delivery

Abstract: Chitosan nanoparticles (NPs) are widely studied as vehicles for drug, protein, and gene delivery. However, lack of sufficient stability, particularly under physiological conditions, render chitosan NPs of limited pharmaceutical utility. The aim of this study is to produce stable chitosan NPs suitable for drug delivery applications. Chitosan was first grafted to phthalic or phenylsuccinic acids. Subsequently, polyphosphoric acid (PPA), hexametaphosphate (HMP), or tripolyphosphate (TPP) were used to achieve tandem ionotropic/covalently crosslinked chitosan NPs in the presence of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC). Thermal and infrared traits confirmed phosphoramide bonds formation tying chitosan with the polyphosphate crosslinkers within NPs matrices. DLS and TEM size analysis indicated spherical NPs with size range of 120 to 350 nm. The generated NPs exhibited excellent stabilities under harsh pH, CaCl2, and 10% FBS conditions. Interestingly, DLS, NPs stability and infrared data suggest HMP to reside within NPs cores, while TPP and PPA to act mainly as NPs surface crosslinkers. Drug loading and release studies using methylene blue (MB) and doxorubicin (DOX) drug models showed covalent PPA- and HMP-based NPs to have superior loading capacities compared to NPs based on unmodified chitosan, generated by ionotropic crosslinking only or covalently crosslinked by TPP. Doxorubicin-loaded NPs were of superior cytotoxic properties against MCF-7 cells compared to free doxorubicin. Specifically, DOX-loaded chitosan-phthalate polyphosphoric acid-crosslinked NPs exhibited 10-folds cytotoxicity enhancement compared to free DOX. The use of PPA and HMP to produce covalently-stabilized chitosan NPs is completely novel.

A comparative study between a virtual reality heart anatomy system and traditional medical teaching modalities

Abstract: The aim of using virtual reality (VR) as a medical training tool is to offer additional means to teach students and to improve the quality of medical skills. A novel system was developed to fulfil the requirements of modern medical education and overcome the challenges faced by both students and lecturers in the process of knowledge transfer. A heart three-dimensional model presented in a virtual reality (VR) environment has been implemented in order to facilitate a new educational modality. This paper reports the outcome of a comparative study between traditional medical teaching modalities and virtual reality technology. This study was conducted in the Faculty of Medicine in the University of Jordan. The participants were asked to perform system trials and experiment with the system by navigating through the system interfaces, as well as being exposed to the traditional physical model of the human heart that is currently used in the faculty during practical anatomy sessions. Afterwards, they were asked to provide feedback via a comparative questionnaire. The participants’ replies to the questions regarding the Physical Heart Model and VR heart anatomy system were assessed for reliability using Cronbach’s alpha. The first group’s (Physical Heart Model questions) α value was 0.689. The second group’s (VR heart anatomy system questions) α value was 0.791. Comparing students’ experience results between the traditional method (Physical Heart Model) and the VR heart anatomy system, the mean scores showed a distinct increase in the values. This indicates that the developed system enhanced their experience in anatomy learning and the provided tools improved their understanding of heart anatomy. Results demonstrated the usefulness of the system by showing a higher satisfaction rate for the provided tools regarding structure and visualisation.