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Insights into Faculty-Librarian Collaborations around the Framework Findings from the 2018 Co-design Survey
No full textSince the 1980s, assessment has been one of the most frequently investigated topics in library and information science literature, seen by librarians as a valid tool for analyzing the effectiveness and impact of teaching. With this in mind, after the Paris workshop and the rollout of the co-designed pilot courses, the AMICAL Information Literacy Committee (ILC) wanted to assess whether the courses had been successful with regard to both learning and teaching and to determine new fruits the co-designing had produced. A second, but equally important, motivation was to report back to the AMICAL Consortium, which funded and supported our project from the beginning. The main goal was to collect qualitative feedback to give insight into the projects and to build a "thick description" of the teaching experience. In order to effectively assess the course design project, as well as provide essential feedback to our stakeholders, the ILC developed and administered a survey about the co-design experience. This survey was conducted among twenty-six participants from eleven different liberal arts institutions outside the United States that are all members of the AMICAL Consortium (appendix 2A). The survey participants came from diverse countries: Lebanon, Armenia, the United Arab Emirates, Morocco, Kuwait, Italy, Switzerland, Kyrgyzstan, Bulgaria, Kosovo, and France. It is interesting to see how the teaching experience and the idea of liberal arts education unfolds within the local contexts of these different cultures as well as different disciplines. For instance, for a better understanding of classroom dynamics, aspects such as attitudes toward female teachers or methods used to teach history in different countries must be taken into account when analyzing responses
Machine Learning Based Real-Time Earthquake Signal Prediction
No full textA Master of Science thesis in Mechatronics Engineering by Sara Tellab entitled, “Machine Learning Based Real-Time Earthquake Signal Prediction”, submitted in November 2020. Thesis advisor is Dr. Usman Tariq and thesis co-advisor is Dr. Mohammad AlHamaydeh. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Processing the ground motion signal at an early stage is beneficial for issuing warnings, applying corrective measures and deploying first-responders teams, etc. As an earthquake starts, our proposed machine learning systems take in the first arriving points of a ground acceleration signal and predict the upcoming points in all three axes. The training, validation and testing data is acquired from the Pacific Earthquake Engineering Research Center (PEER) NGAWest2 database. It includes shallow crustal earthquakes with hypocenters less than 20 km deep. The research methodology applies different aspects of supervised and unsupervised learning. We analyze the metadata of previous earthquake records such as the magnitude, horizontal distance and peak ground acceleration (PGA). Moreover, we train various structures of artificial neural networks (ANNs) such as convolutional neural networks (CNN), recurrent neural networks (RNN), long short-term memory (LSTM) networks and CNNLSTMs. The ANN model serves as a baseline for performance evaluation of the other models. We rely on the sliding window approach to split the acceleration signal. It was found that the best model for short term prediction was the LSTM model for a prediction horizon of ten timesteps. It yielded a root mean squared error (RMSE) of 8.43e6 which is a 95.2% improvement in performance compared to the baseline that yielded an RMSE of 1.74e4 . In addition, the prediction time for the CNN model is 0.49 , which makes it the fastest model. Moreover, the CNN, ANN and CNNLSTM models experimented with in this work, yielded real-time performance. The other models can also produce faster predictions using more GPUs or a supercomputer.College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
Heterometrus spinifer: An Untapped Source of Anti-Tumor Molecules
No full textDespite intensive research, cancer incidence and mortality continue to rise. Consequently, the necessity to develop effective anti-cancer therapy is apparent. We have recently shown that the gut bacteria of animals living in polluted environments, such as crocodiles, are a potential source of novel anti-tumor molecules. To extend this work to other resilient species, we investigated the anti-tumor effects of gut bacteria of Heterometrus spinifer (a scorpion). Bacteria from the feces and gut were isolated, identified and evaluated for their anti-tumor effects. Bacterial-conditioned media was prepared in Roswell Park Memorial Institute (RPMI) 1640 media, and cytotoxicity and growth inhibitory properties were examined against cervical (HeLa) cancer cells. Liquid chromatography–mass spectrometry (LC-MS) was conducted to establish the identity of the molecules. Eighteen bacteria species from the gut (HSG01-18) and ten bacteria species from feces (HSF01-10) were tested for anti-tumor effects. Bacterial-conditioned media from scorpion gut and feces exhibited significant growth inhibitory effects against HeLa cells of 66.9% and 83.8%, respectively. Microscopic analysis of cancer cells treated with conditioned media HSG12 and HSG16 revealed apoptosis-like effects. HSG12 was identified as Pseudomonas aeruginosa and HSG16 was identified as Bacillus subtilis. Both conditioned media exhibited 100% growth inhibitory effects versus a selection of cancer cells, comprising cervical, breast and prostate cancer cells. LC–MS indicated the presence of 72 and 38 compounds, detected from HSG12 and HSG16, respectively. Out of these compounds, 47 were successfully identified while the remainder were unidentified and are possibly novel. This study suggests that the fecal and gut microbiota of scorpions might possess molecules with anti-cancer properties, however, further intensive research is needed to assess these expectations
Scorpion and Frog Organ Lysates are Potential Source of Antitumour Activity
No full textIt is noteworthy that several animal species are known to withstand high levels of radiation, and are exposed to heavy metals but rarely been reported to develop cancer. For example, the scorpion has been used as folk medicine in ancient civilizations of Iran and China, while amphibian skin is known to possess medicinal properties. Here, we elucidated the anti-tumour activity of the scorpion (Uropygi) and frog (Lithobates catesbeianus). Materials and Methods: Animals were procured and their organ lysates and sera were prepared and tested against Michigan Cancer Foundation-7 breast cancer (MCF-7), prostate cancer (PC3), Henrietta Lacks cervical cancer (HeLa), and normal human keratinocyte cells. Exoskeleton, appendages and hepatopancreas were dissected from the scorpion, whereas liver, lungs, heart, oviduct, gastrointestinal tract, gall bladder, kidneys, eggs and sera were collected from frog and organ lysates/sera were prepared. Growth inhibition assays and cytotoxicity assays were performed. Results: Appendages, exoskeleton lysates, and hepatopancreas from scorpion exhibited potent growth inhibition, and cytotoxic effects. Furthermore, lungs, liver, gastrointestinal tract, heart, oviduct, kidneys, eggs, and sera from frog displayed growth inhibition and cytotoxic effects. Conclusion: Organ lysates, sera of scorpion, and amphibians possess anti-tumour activities. This is a worthy area of research as the molecular identity of the active molecule(s) together with their mechanism of action will lead to the rational development of novel anticancer agent(s).American University of Sharja
Whole Organism Model to Study Molecular Mechanisms of Differentiation and Dedifferentiation
No full textCancer recurrence has remained a significant challenge, despite advances in therapeutic approaches. In part, this is due to our incomplete understanding of the biology of cancer stem cells and the underlying molecular mechanisms. The phenomenon of differentiation and dedifferentiation (phenotypic switching) is not only unique to stem cells but it is also observed in several other organisms, as well as evolutionary-related microbes. Here, we propose the use of a primitive eukaryotic unicellular organism, Acanthamoeba castellanii, as a model to study the molecular mechanisms of cellular differentiation and dedifferentiation.American University of Sharja
Variability of the Oceans
No full textThe oceans have a huge capability to store, release, and transport heat, water, and various chemical species on timescales from seasons to centuries. Their transports affect global energy, water, and biogeochemical cycles and are crucial elements of Earth’s climate system. Ocean variability, as represented, for example, by sea surface temperature (SST) variations, can result in anomalous diabatic heating or cooling of the overlying atmosphere, which can in turn alter atmospheric circulation in such a way as to feedback on ocean thermal and current structures to modify the original SST variations. Ocean–atmosphere interactions in one ocean basin can also influence remote regions via interbasin teleconnections that can trigger responses having both local and far-field impacts. This chapter highlights the defining aspects of the climate in individual ocean basins, including mean states, seasonal cycles, interannual-to-interdecadal variability, and interactions with other basins. Key components of the global and tropical ocean observing system are also describe
Balun LNA Thermal Noise Analysis and Balancing With Common-Source Degeneration Resistor
No full textThe Balun low noise amplifier (LNA) is an LNA that exploits a combination of a common-source (CS) and a common-gate (CG) transistors, which cancels the noise and distortion of the CG stage. And since the CG is known to be linear, only the CS needs to be carefully designed and optimized. The Balun LNA also cancels the distortion and noise of the CG. In this paper, the CS section will be fully analyzed, and shown how the condition set in the literature review still satisfy the balancing output and cancel the CS stage thermal noise as well as the CG thermal noise. Also, forward body biasing (FBB) is used to reduce the threshold voltage and an addition of CS degeneration resistor to balance the output while still canceling the thermal noise of the transistors is tested using UMC180nm on Cadence. The LNA achieves a gain of 19-16dB, NF <; 3.6 over the bandwidth 200M-1.9GHz without a CS degeneration. A 17.8-14.8dB gain, a NF <; 3.8 over the bandwidth 200MHz-2.1GHz and power consumption of 12mW in both cases. Although outside the bandwidth, at ISM 2.4GHz a gain of 14.5dB and a NF of 3.8 is achieved, making it suitable for wireless sensor node (WSN) applications. According to the author's knowledge, this is the first time the degeneration resistor noise analysis on a Balun LNA is derived and analyzed.American University of Sharja
CFD Modeling of Biomass Thermal Conversion in A Novel Solar-Thermal Reactor
No full textA Master of Science thesis in Chemical Engineering by Rania Ahmed entitled, “CFD Modeling of Biomass Thermal Conversion an A Novel Solar-Thermal Reactor”, submitted in May 2020. Thesis advisor is Dr. Yassir Makkawi. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).The excessive utilization of fossil fuels during the past five decades resulted in a gradualdepletion of reserves and caused a serious negative impact on the environment, such as air pollution, climate change and acid rain. To sustain and meet the world’s energy demand, bioenergy is being extensively researched for sustainable production of clean and renewable fuels. Biomass pyrolysis, which is one of the main bioenergy technologies, is a highly endothermic process, where the primary products are a pyrolytic liquid phase (bio-oil), a solid phase (bio-char), and a gas (non-condensable gases). To minimize the energy demand for biomass pyrolysis, a hybrid system combining solar-thermal with biomass is a promising and cost-effective option for large-scale implementation. This thesis focuses on the thermochemical conversion of biomass via fast pyrolysis for biofuels (liquid bio-oil and gas) and biochar production in a novel solar-thermal conversion reactor. The study is purely theoretical and mainly involves developing and solving a Computational Fluid Dynamic (CFD) model using ANSYS Fluent software package, to predict the flow hydrodynamics, heat transfer, reactions, and products of pyrolysis. A flow hydrodynamic model (solid/gas velocity, pressure, and solid distribution) was firstly created and solved using the Eulerian- Eulerian approach, with constitutive equations based on Kinetic Theory of Granular Flow (KTGF). This was followed by a sensitivity analysis to assess the effect of meshing, drag models and turbulence on the model predictive capabilities. Consequently, a reliable hydrodynamic model was endorsed and validated using preexisting experimental data obtained at the AUS labs using an advanced Particle Image Velocimetry (PIV) measuring technique. The validated model was then upgraded by incorporating heat transfer, drying and devolatilization of the pyrolysis reaction equations, to envisage the performance of the proposed novel reactor design. The predicted bio-oil, bio-char and non-condensable gases were found to be qualitatively and quantitatively valid, thus lending strong support to the feasibility of the proposed concept. It is hoped that the model will be a cornerstone for future development and scale-up of the proposed novel solar-thermal reactor.College of EngineeringDepartment of Chemical EngineeringMaster of Science in Chemical Engineering (MSChE
Uptake of Chromium by Portulaca Oleracea from Soil: Effects of Organic Content, pH, and Sulphate Concentration
No full textPhytoextraction is an effective and environment-friendly approach for remediation of soil polluted with toxic metals. Portulaca oleracea is a potential hyperaccumulator of Cr(VI) from polluted soil. In this study, the effect of soil organic content, pH, and sulphate concentration on phytoextraction of Cr(VI) using Portulaca oleracea was investigated. Seedlings of Portulaca oleracea were grown in soils with (i) three organic content compositions, (ii) six levels of pH, and (iii) six concentrations of sulphate salts; all were irrigated with Cr(VI) solutions at 200 ppm concentration. Chromium concentration in different tissues of plants was monitored under the variant conditions. Results indicated that the uptake of Cr(VI) by Portulaca oleracea is favoured at (i) low organic content soil (0.42%), (ii) slightly alkaline pH range (∼8), and (iii) with sulphate concentration in the range of 300–600 ppm
Ultrasound triggered drug delivery of transferrin coupled liposomes carrying the drug doxorubicin
No full textA Master of Science thesis in Chemical Engineering by Paul Said Kawak entitled, “Ultrasound triggered drug delivery of transferrin coupled liposomes carrying the drug doxorubicin”, submitted in June 2020. Thesis advisor is Ghaleb Al Husseini. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).Cancer is one of the deadliest diseases of the 21st century. It is caused by the uncontrolled division of damaged and mutated cells. Several methods have been developed to combat cancer, including surgery, radiation, and chemotherapy. However, due to the nature of the disease and the cytotoxicity of the treatments, these treatments' effectiveness is limited. To mitigate the cytotoxicity of these treatments and improve efficacy, Smart Drug Delivery Systems are studied. These delivery systems contain nanoparticle that encapsulates a chemotherapeutic drug and delivers it selectively to the tumor site. This work will utilize a PEGylated liposome coupled with the protein Transferrin encapsulating the chemotherapeutic drug Doxorubicin. The PEG protects the vesicles from the human body's immune system. The vesicle can passively target the tumor site. Moreover, the transferrin ligand selectively binds to cancer cells, improving uptake chances. The liposomes were synthesized using the film hydration method. The averaged size of the control liposomes and Transferrin-targeted liposomes are 85.2 ± 5.83 nm, and 85.3 ± 7.15 nm, respectively. The lipid content of the liposomes is quantified, and the result for control liposomes is 8.024 ± 0.126 mg/ml, while the result for the Tf-targeted liposomes is 6.219 ± 1.109 mg/ml using the Stewart Assay. The conjugation of Transferrin proven using the BCA assay as the protein content was 2-fold higher than the control liposomes. Low-frequency ultrasound release is conducted using a 20-kHz US probe at three power densities, namely, 7.46, 9.85, 17.31 mW/cm2, and the results showed an increase in the release of Doxorubicin from the transferrin coupled liposomes. The release results are fitted to nine different models, and the best-fitting model is the zero-order model. The second and third best-fitting models are Hixson-Crowell and Hopfenberg. Using three modalities of drug delivery targeting (passive, ligand, and acoustic triggered) may aid in curbing the unwanted side effects of conventional chemotherapy.College of EngineeringDepartment of Chemical EngineeringMaster of Science in Chemical Engineering (MSChE