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Encapsulation, Release, and Cytotoxicity of Doxorubicin Loaded in Liposomes, Micelles, and Metal-Organic Frameworks: A Review
No full textDoxorubicin (DOX) is one of the most widely used anthracycline anticancer drugs due to its high efficacy and evident antitumoral activity on several cancer types. However, its effective utilization is hindered by the adverse side effects associated with its administration, the detriment to the patients’ quality of life, and general toxicity to healthy fast-dividing cells. Thus, delivering DOX to the tumor site encapsulated inside nanocarrier-based systems is an area of research that has garnered colossal interest in targeted medicine. Nanoparticles can be used as vehicles for the localized delivery and release of DOX, decreasing the effects on neighboring healthy cells and providing more control over the drug’s release and distribution. This review presents an overview of DOX-based nanocarrier delivery systems, covering loading methods, release rate, and the cytotoxicity of liposomal, micellar, and metal organic frameworks (MOFs) platforms.Dana Gas Endowed Chair for Chemical EngineeringAmerican University of SharjahSheikh Hamdan Award for Medical Science
Graph of Linear Transformations Over R
No full textIn this paper, we study a connection between graph theory and linear transformations of finite dimensional vector spaces over R (the set of all real numbers). Let Rm, Rn be finite vector spaces over R, and let L be the set of all non-trivial linear transformations from Rm into Rn. An equivalence relation ∼ is defined on L such that two elements f, k ∈ L are equivalent, f ∼ k, if and only if ker (f ) = ker (k). Let m, n ≥ 1 be positive integers and Vm,n be the set of all equivalence classes of ∼. We define a new graph, Gm,n, to be the undirected graph with vertex set equals to Vm,n, such that two vertices, [x] , [y] ∈ Vm,n are adjacent if and only if ker (x) ∩ ker (y) 6 = 0. The relationship between the connectivity of the graph Gm,n and the values of m and n has been investigated. We determine the values of m and n so that Gm,n is a complete graph. Also, we determine the diameter and the girth of Gm,n
Fluoroscopic 3D Images Generation Using A GAN Method
No full textA Master of Science thesis in Biomedical Engineering by Mohammad Nabeel Mohammad Alshrbaji entitled, “Fluoroscopic 3D Images Generation Using A GAN Method”, submitted in December 2022. Thesis advisor is Dr. Salam Dhou. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Respiratory motion is a major source of error in radiation therapy for thorax and lung cancer. Image-Guided Radiation Therapy (IGRT) is the use of frequent imaging during radiation therapy to enhance the precision and accuracy of the treatment delivery. Cone Beam Computed Tomography (CBCT) is an imaging modality that is used in radiotherapy delivery rooms to account for respiratory motion uncertainties. One CBCT scan results in a set of projections (2D images), which is taken in a couple of minutes while the patient is normally breathing. The known procedure for utilizing these projections is to sort them into breathing phases and reconstruct a 3D image from each, which results in making 4D-CBCT images. These 4D-CBCT images are used to estimate fluoroscopic images right before the treatment delivery. The objective of this work is to generate 3D fluoroscopic images of the lungs from two orthogonal projections using a Generative Adversarial Network (GAN) method. GAN is a powerful deep learning-based technique that allows two independent models to develop and compete with each other, which are named the generator (G) and the discriminator (D). This method has the potential of generating a 3D volume image representing patient anatomy at the time of treatment delivery from any two orthogonal projections. Using multiple pairs of projections from multiple pairs of angles, the model can generate a 3D fluoroscopic image representing the respiratory motion while the patient is in the treatment position. The resulting generated 3D images give very good results in terms of generating quality images representing the same breathing phase as the orthogonal projections. The quantitative results include the measures of Peak Signal-to-Noise Ratio (PSNR) and Structural Similarity Index (SSIM), which equal 26.01 and 0.572, respectively. Although the proposed method does not intend to replace the used motion model-based methods, its goal is to add niche applications in radiation therapy, such as tumor tracking and dose verification.College of EngineeringMultidisciplinary ProgramsMaster of Science in Biomedical Engineering (MSBME
Efficient Extraction of Methylene Blue from Aqueous Solution Using Phosphine-Based Deep Eutectic Solvents with Carboxylic Acid
No full textMethylene blue (MB), an organic thiazine dye, has numerous industrial and medical applications. However, MB is a wastewater contaminant that is harmful to humans and aquatic life. Hence, its removal from water bodies is essential. In this work, five novel deep eutectic solvents (DESs) were synthesized using different precursors, screened, and studied for the extraction of methylene blue (MB) from aqueous solution using liquid–liquid extraction. The first, TOP-SA, was synthesized using trioctylphosphine (TOP) as a hydrogen bond acceptor (HBA) and 2-hydroxy benzoic acid as a hydrogen bond donor (HBD). Among these, TOP-SA had the highest MB removal efficiency. The effects of pH, contact time, initial MB concentration, volumetric ratio, temperature, and ionic strength were studied and optimized. A 99.3% removal was achieved in 5 min for a 200 mg dm−3 MB solution mixed in a 1:10 ratio with TOP-SA at 25.0 °C. The structural properties of TOP-SA and its interactions with MB were investigated using FTIR. TOP-SA’s toxicity was investigated using human cells in vitro. TOP-SA was found to be comparatively less toxic and is a more efficient MB remover than other literature reported ionic liquids (ILs).American University of Sharja
FEA Investigation of Elastic Buckling for Functionally Graded Material (FGM) Thin Plates with Different Hole Shapes under Uniaxial Loading
No full textIn this paper, an investigation of linear eigenvalue buckling of functionally graded material (FGM) plates under uniaxial loading is carried out. The computer model is analyzed using the finite element (FE) package ABAQUS. An analysis is carried out to study the effect of the size and geometry of openings in the FGM plate on the critical buckling load. The circular, square, and diamond openings vary in size based on the ratio of the opening diameter to the width of the FGM plate. Moreover, the effect of the aspect ratio (width to thickness) of the FGM plate on the critical buckling load is examined. Further, the effect of the power law index on buckling behavior is investigated. The results show that the increase in the size of the opening and the aspect ratio reduces the critical buckling load of the FGM plate. Moreover, the lower the power law index, the higher the critical buckling load. The diamond shape opening shows the best performance in terms of the critical buckling load, and the effect of the plate thickness has a more significant influence on the critical buckling load of the FGM plate compared to the size of the opening.American University of Sharja
Optimal Operation of Virtual Charging Systems for Plug-In Electric Vehicles
No full textThis paper proposes a novel concept, denoted as Virtual Charging System (VCS), for electric vehicles’ (EVs). In a conventional charging system (CCS) with a competitive environment, the competition between charging stations can utilize game theory as a price competition game model. On contrary, charging stations with different ownerships under the VCS umbrella will cooperate to act as one charging station for EV drivers in order to increase customer satisfaction and obtain more profits collectively and individually. The proposed VCS consists of three parts: participating charging stations, EVs contracting with the VCS, and finally the VCS operator. The operator is responsible for optimally routing the EVs to a suitable charging station within the VCS. A new formulation for implementing this novel concept is presented to allow interaction between various VCSs to maximize the profit gained by each VCS as well as minimize the transit charging time and cost for each customer as a measure representing customer satisfaction. Different case studies are introduced to evaluate the significance of the VCS concept. The performance of the VCS is compared to CCS, and the results show that VCS provides superior customer satisfaction and higher profit.American University of SharjahKhalifa University of Science, Technology and Researc
Impacts of COVID-19 on the Use of Digital Technology in Construction Projects in the UAE
No full textThe construction industry has been incorporating digital technology over the last two decades, albeit gradually, as “technology-push” continues to overcome customary and traditional passivity typical in the sector. The objective of the study presented in this paper is to investigate how digital technology is making a headway in the construction industry as a consequence of COVID-19. For the purpose of this paper, digital technology applications are divided into three groups: data acquisition, processing, and communication. The methodology involved conducting a questionnaire survey among the construction professionals in the UAE. The survey included questions on the extent of use and level of investment on the three types of technology in three periods—pre-COVID, during COVID, and post-COVID. The results clearly show the increasing level of usage of digital technology in the construction industry from pre-COVID to during COVID and post-COVID periods. Among the three categories, communication technology indicated higher extent of use as compared to the other two. In addition, a marked difference was observed between the “small” project organizations and the “large” ones. Unsurprisingly, both usage and investment in digital technology, in smaller organizations, indicated higher extent of increase in during and post-pandemic periods when compared to the larger organizations.American University of Sharja
Language Anxiety and The Classroom Elements That Provoke It
No full textA Master of Arts thesis in Teaching English to Speakers of Other Languages (TESOL) by Alya Yusuf Yahya Alkhaja entitled, “Language Anxiety and The Classroom Elements That Provoke It”, submitted in May 2022. Thesis advisor is Dr. Tammy Gregersen. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Language anxiety is prevalent in second\foreign language classrooms. This study investigates the language skills that provoke students’ anxiety. It also explores which of the three types of classroom configurations (pair work, small group work, or whole group discussion) provoke the most language anxiety in second language classes. The study involved 28 “Bridge Program” students who were taking non-credit English classes to increase their proficiency level in the four language skills in order to pass the necessary requirements to be accepted into university credit-bearing classes. To conduct this study, two data collection cycles were used to answer the research questions. For cycle one, participants self-reported their levels of language anxiety pre- and post- task completion using an “axometer”, which can be referred as an “anxiety thermometer”. An axometer is a scale with a range of values from one to ten, whereby marking “one” means participants were self-reporting that they were ‘not anxious at all’, while marking “ten” meant ‘extremely anxious’. For cycle two, participants were asked to self-report their anxiety levels after spending ten minutes in whole group discussion, small group work, and pair work. The results of cycle one demonstrated that students reported that writing is the language skill that provokes the greatest anxiety. Moreover, it indicated that students are less anxious when the task is accomplished regardless of their fear of losing marks, errors, and social anxiety pre and post the task. Thus, students are leaning toward a ‘downward trend’ which refers to having a lower anxiety level after completing a given task. In the second phase of the study where the question involved participants’ feelings toward group configurations, students self-reported that small group work provoked the greatest amount of anxiety, while working in pairs incited the lowest.College of Arts and SciencesDepartment of EnglishMaster of Arts in Teaching English to Speakers of Other Languages (MA TESOL
Music Aptitude and Phonemic Processing
No full textA Master of Arts thesis in Teaching English to Speakers of Other Languages (TESOL) by Aya Mohammed Sallam entitled, “Music Aptitude and Phonemic Processing”, submitted in November 2022. Thesis advisor is Dr. Ji Young Shim. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Music aptitude and second language (L2) phonemic processing are said to be connected via the processing of sounds, which also known as acoustic processing. Previous literature on this topic discusses how vowels are associated with musical chords and harmonic frequencies while consonants are associated with staccato and legato in music. Results from many previous studies strongly indicate that music aptitude may facilitate the processing of vowels in an L2 whereas results on music aptitude and L2 consonant processing are inconsistent.
While some argue that music aptitude may facilitate consonant phonemic processing (Jekiel & Malarsji, 2021; Magne et al., 2016; Sadakata & Sekiyama, 2011), others claim that there is no correlation between music aptitude and consonant phonemic processing (Milovanov & Tervaniemi, 2010; Swaminathan & Schellenberg, 2017). Against this background, the current study investigated whether music aptitude of Arabic speakers is closely related to their L2 English consonant phonemic processing, with particular focus on the three English consonant phonemes that do not exist in Arabic, /p/, /v/, and /θ/. They were compared to three phonemes, /b/, /f/, and /s/, which exist both Arabic and English. Results from 30 Arabic speakers showed that Arabic speakers’ music aptitude and their consonant phonemic processing in English were strongly correlated (p < .05). In other words, Arabic speakers with better music aptitude perceived the three English phonemes that do not exist in their native language. On the other hand, there was no difference in response time, which suggests that better L2 phonemic processing is not related to faster L2 phonemic processing. The findings of the study also suggest music as a pedagogical tool to teaching English as an L2 and in an L2 classroom overall.College of Arts and SciencesDepartment of EnglishMaster of Arts in Teaching English to Speakers of Other Languages (MA TESOL
Guatemalan Teenagers’ Hopes and Dreams: A Qualitative Study of Drawings and Characteristics of Future Selves
No full textUtilizing adolescents' drawings in order to investigate their perceptions of self has a long history in psychology. The methodological approach is particularly useful in places, such as Guatemala, where the population may have relatively lower levels of literacy and/or less experience engaging with Western-style research surveys. By asking adolescents to draw a picture of themselves and list five characteristics that they hope to have in 15 years, we were able to collect valuable data on issues such as the students' desires for the future and what they see as possible for themselves. Participants (N = 81, Mage = 14.56 years, 49.4% cisgender girls, all from Jocotenango, Guatemala) provided five characteristics that they hoped to have 15 years in the future, and then drew a self-portrait of themselves 15 years in the future. The drawings and characteristics underwent a process of thematic analysis to determine patterns and themes that are prevalent in the data. Common themes that emerged among the characteristics include jobs or specific professions they hope to have, owning a home or property such as a car, and having a family. In the drawings, the common themes are similar: mentioning specific careers, owning a home or property, and having a family. This data can help us determine what type of futures these students hope for in order to ensure that schools and other institutions are providing the tools students will need for those futures