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Biophysical model of coral population connectivity in the Arabian/Persian Gulf
No full textThis is a summary of the book chapter.The coral reef ecosystems of the Arabian/Persian Gulf (the Gulf ) are facing profound pressure from climate change (extreme temperatures) and anthropogenic (land-use and population-related) stressors. Increasing degradation at local and regional scales has already resulted in widespread coral cover reduction. Connectivity, the transport and exchange of larvae among geographically separated populations, plays an essential role in recovery and maintenance of biodiversity and resilience of coral reef populations.
Here, an oceanographic model in 3-D high-resolution was used to simulate particle dispersion of “virtual larvae.” We investigated the potential physical connectivity of coral reefs among different regions in the Gulf. Simulations reveal that basin-scale circulation is responsible for broader spatial dispersion of the larvae in the central region of the Gulf, and tidally-driven currents characterized the more localized connectivity pattern in regions along the shores in the Gulf’s southern part. Results suggest predominant self-recruitment of reefs with highest source and sink ratios along the Bahrain and western Qatar coasts, followed by the south eastern Qatar and continental Abu Dhabi coast. The central sector of the Gulf is suggested as recruitment source in a stepping-stone dynamics. Recruitment intensity declined moving away from the Straits of Hormuz. Connectivity varied in models assuming passive versus active mode of larvae movement. This suggests that larval behaviour needs to be taken into consideration when establishing dispersion models, and establishing conservation strategies for these vulnerable ecosystems
Health benefits of sesamin on cardiovascular disease and its associated risk factors
No full textSesamin, a major lignin isolated from sesame (Sesamum indicum) seeds and sesame oil, is known to possess antioxidant and anti-inflammatory properties. Several studies have revealed that oxidative stress and inflammation play a major role in a variety of cardiovascular diseases (CVDs). This comprehensive review summarizes the evidence on the effects of sesamin on CVD and its risk factors, principally due to its antioxidant properties. Specifically, this review highlights the mechanisms underlying the anti-hypertensive, anti-atherogenic, anti-thrombotic, anti-diabetic, and anti-obesity, lipolytic effects of sesamin both in vivo and in vitro, and identifies the signaling pathways targeted by sesamin and its metabolites. The data indicates that RAS/MAPK, PI3K/AKT, ERK1/2, p38, p53, IL-6, TNFα, and NF-κB signaling networks are all involved in moderating the various effects of sesamin on CVD and its risk factors. In conclusion, the experimental evidence suggesting that sesamin can reduce CVD risk is convincing. Thus, sesamin can be potentially useful as an adjuvant therapeutic agent to combat CVD and its multitude of risk factors.American University of Sharja
Low-Cost Reduced Navigation System for Mobile Robot in Indoor/Outdoor Environments
No full textThis paper presents a low-cost based approach for solving the navigation problem of wheeled mobile robots to perform required tasks within indoor and outdoor environments. The presented solution is based on probabilistic approaches for multiple sensor fusion utilizing low-cost visual/inertial sensors. For the outdoor environment, the Extended Kalman Filter (EKF) is used to estimate the robot position and orientation, the system consists of wheel encoders, a reduced inertial sensor system (RISS), and a Global Positioning System (GPS). For the indoor environment, where GPS signals are blocked, another EKF algorithm is proposed using low cost depth sensor (Microsoft Kinect stream). EKF indoor localization is based on landmarks extracted from the depth measurements. A hybrid low-cost reduced navigation system (HLRNS) for indoor and outdoor environments is proposed and validated in both simulation and experimental environments. Additionally, an input-output state feedback linearization (I-O SFL) technique is used to control the robot to track the desired trajectory in such an environment. According to the conducted validation simulation and experimental testing, the proposed HLRNS provides an acceptable performance to be deployed for real-time applications
Deep Learning Detection of Electricity Theft Cyber-Attacks in Renewable Distributed Generation
No full textUnlike the existing research that focuses on detecting electricity theft cyber-attacks in the consumption domain, this paper investigates electricity thefts at the distributed generation (DG) domain. In this attack, malicious customers hack into the smart meters monitoring their renewable-based DG units and manipulate their readings to claim higher supplied energy to the grid and hence falsely overcharge the utility company. Deep machine learning is investigated to detect such a malicious behavior. We aim to answer three main questions in this paper: a) What are the cyber-attack functions that can be applied by malicious customers to the generation data in order to falsely overcharge the utility company? b) What sources of data can be used in order to detect these cyber-attacks by the utility company? c) Which deep machine learning-model should be used in order to detect these cyber-attacks? Our investigation revealed that integrating various data from the DG smart meters, meteorological reports, and SCADA metering points in the training of a deep convolutional-recurrent neural network offers the highest detection rate (99:3%) and lowest false alarm (0:22%).Qatar National Research Fun
AEBP1 is a Novel Oncogene: Mechanisms of Action and Signaling Pathways
No full textAdipocyte enhancer-binding protein 1 (AEBP1) is a transcriptional repressor involved in the regulation of critical biological processes including adipogenesis, mammary gland development, inflammation, macrophage cholesterol homeostasis, and atherogenesis. Several years ago, we first reported the ability of AEBP1 to exert a positive control over the canonical NF-κB pathway. Indeed, AEBP1 positively regulates NF-κB activity via its direct interaction with IκBα, a key NF-κB inhibitor. AEBP1 overexpression results in uncontrollable activation of NF-κB, which may have severe pathogenic outcomes. Recently, the regulatory relationship between AEBP1 and NF-κB pathway has been of great interest to many researchers primarily due to the implication of NF-κB signaling in critical cellular processes such as inflammation and cancer. Since constitutive activation of NF- κB is widely implicated in carcinogenesis, AEBP1 overexpression is associated with tumor development and progression. Recent studies sought to explore the effects of the overexpression of AEBP1, as a potential oncogene, in different types of cancer. In this review, we analyze the effects of AEBP1 overexpression in a variety of malignancies (e.g., breast cancer, glioblastoma, bladder cancer, gastric cancer, colorectal cancer, ovarian cancer, and skin cancer), with a specific focus on the AEBP1-mediated control over the canonical NF-κB pathway. We also underscore the ability of AEBP1 to regulate crucial cancer-related events like cell proliferation and apoptosis in light of other key pathways (e.g., PI3K-Akt, sonic hedgehog (Shh), p53, parthanatos (PARP-1), and PTEN). Identifying AEBP1 as a potential biomarker for cancer prognosis may lead to a novel therapeutic target for the prevention and/or treatment of various types of cancer
Hyper-Consumption to Circular Economy in the United Arab Emirates: Discarding the Disposable and Cherishing the Valuable
No full textOverconsumption of resources and consumer items is an important driver for environmental degradation and climate change. Malls, shopping, and conspicuous consumption are deeply ingrained in the local values and the global image of the United Arab Emirates (UAE). The UAE has a diverse and international population with over 85% expats and numerous opportunities to reduce environmental impact. Increased participation in a circular economy that aims to reduce resource use by recycling materials, reusing products, extending their lifespan, and maintaining their economic value would be an effective strategy to reduce negative environmental impacts. However, little is known about how much and why UAE citizens and residents participate in the circular economy. Therefore, it is important to examine the factors that predict participation in the circular economy in the UAE. To investigate this question, we surveyed n=163 undergraduate students at an American-curriculum university in the UAE and explored literature-based explanations as predictors for participation in the circular economy, namely gender, nationality, exposure to circular economy initiatives, efforts to reduce ecological footprints, and sustainable consumer behaviors using index-based negative binomial regression models. We also compare differences in ways and levels of participation in the circular economy between UAE citizens and residents with t-tests. Our results suggest that participation in the circular economy does not emerge from concerted efforts to reduce environmental degradation such as lowering ecological footprint and reducing waste, but rather investments in sustainable and durable items. Emirati citizens are more likely to participate in the circular economy, in particular repairing items, than expat residents. These differences are most likely to be explained by the more stable lifestyles of Emirati citizens as opposed to the more itinerant lifestyles of expat residents
A Robotic System for Automatic Identification and Collection of Recyclable Plastic Bottles
No full textA Master of Science thesis in Electrical Engineering by Uzma Ahmed Din entitled, “A Robotic System for Automatic Identification and Collection of Recyclable Plastic Bottles”, submitted in May 2020. Thesis advisors are Dr Shayok Mukhopadhyay and Dr. Usman Tariq. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).Plastics have become a cornerstone of modern life, but they are also hazardous for the environment. Manually collecting and sorting such recyclable plastic waste from a mix of other refuse is tedious work, and has accompanying health hazards. This project develops a prototype autonomous robot that can identify, and collect plastic bottles from other waste, and return to recycling stations. The focus of this prototype is on the recognition and separation of a particular type of plastic bottle commonly used for packaging drinking water. In this work, the robot navigates to a general location where such plastic waste is expected to be found via GPS based navigation. Then, the robot recognizes recyclable plastic bottles, and computes the coordinates of the plastic bottle with respect to the robot, using a stereo camera. Finally, using a robotic arm attached to it, the robot collects the plastic bottle. This thesis does not focus on developing an appropriate gripper to pick up a bottle as it is out of the scope of the current work. To aid the picking process, the end-effector and bottles are fitted with small magnetic attachments. Moreover, the robot developed is 80% and 67% successful, in indoor and outdoor testing respectively. The future versions of the proposed robot may be advanced to segregate the collected plastic bottle waste into appropriate bins located at a recycling station.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Use of A Hydroalcoholic Extract of Moringa oleifera Leaves for the Green Synthesis of Bismuth Nanoparticles and Evaluation of Their Anti-Microbial and Antioxidant Activities
No full textThe employment of plant extracts in the synthesis of metal nanoparticles is a very attractive approach in the field of green synthesis. To benefit from the potential synergy between the biological activities of the Moringa oleifera and metallic bismuth, our study aimed to achieve a green synthesis of phytochemical encapsulated bismuth nanoparticles using a hydroalcoholic extract of M. oleifera leaves. The total phenolic content in the M. oleifera leaves extract used was 23.0 ∓ 0.3 mg gallic acid equivalent/g of dried M. oleifera leaves powder. The physical properties of the synthesized bismuth nanoparticles were characterized using UV-Vis spectrophotometer, FT-IR spectrometer, TEM, SEM, and XRD. The size of the synthesized bismuth nanoparticles is in the range of 40.4–57.8 nm with amorphous morphology. Using DPPH and phosphomolybdate assays, our findings revealed that the M. oleifera leaves extract and the synthesized bismuth nanoparticles possess antioxidant properties. Using resazurin microtiter assay, we also demonstrate that the M. oleifera leaves extract and the synthesized bismuth nanoparticles exert potent anti-bacterial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecalis (estimated MIC values for the extract: 500, 250, 250, and 250 μg/mL; estimated MIC values for the bismuth nanoparticles: 500, 500, 500, and 250 μg/mL, respectively). Similarly, the M. oleifera leaves extract and the synthesized bismuth nanoparticles display relatively stronger anti-fungal activity against Aspergillus niger, Aspergillus flavus, Candida albicans, and Candida glabrata (estimated MIC values for the extract: 62.5, 62.5, 125, and 250 μg/mL; estimated MIC values for the bismuth nanoparticles: 250, 250, 62.5, and 62.5 μg/mL, respectively). Thus, green synthesis of bismuth nanoparticles using M. oleifera leaves extract was successful, showing a positive antioxidant, anti-bacterial, and anti-fungal activity. Therefore, the synthesized bismuth nanoparticles can potentially be employed in the alleviation of symptoms associated with oxidative stress and in the topic treatment of Candida infections.MNRE, Government of Indi
Mechanical Behavior of Friction Stir Extruded Tubes
No full textA Master of Science thesis in Mechanical Engineering by Abdulla Taoufik Alhourani entitled, “Mechanical Behavior of Friction Stir Extruded Tubes”, submitted in December 2020. Thesis advisor is Dr. Mohammad Ahmad Hasan Nazzal and thesis co-advisor is Dr. Basil Mohammad Darras. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Friction Stir Back Extrusion (FSBE) is a new grade of severe plastic deformation processes capable of producing metallic tubular geometries that exhibit ultrafine grain structure and superior mechanical properties. FSBE of tubular sections provide opportunities for producing lightweight rigid structures for the automotive, aerospace and construction industries. This research investigates the impact of rotational speed and feed rate on the mechanical properties, power consumption and cycle time for FSBE of Magnesium AZ31-B tubes under air cooling medium to determine the optimal settings. The investigation is conducted utilizing Response Surface Methodology (RSM) and desirability multi-response optimization technique. RSM results suggest that the ultimate tensile strength and toughness are impacted by both rotational speed and feed rate and are more sensitive to spindle rotational speed. Yet, both parameters did not show a significant statistical impact on percent elongation. The optimal settings to maximize mechanical properties and minimize production indicators are 2000 rpm and 116 mm/min. Furthermore, the effect of submerging conditions (in water at 25 °C and 2 °C) on the grain size and mechanical properties was investigated and compared to FSBE in air. It is shown that the impact of submerging is statistically insignificant in terms of the mechanical properties of the produced tubes. On the other hand, finer grains were observed at the inner wall of the tube for FSBE in air and underwater FSBE at 25 °C when compared to underwater FSBE at 2 °C.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
The Effects of Emotional Decoding on Eliciting Empathic Responses in Language Teachers: An Idiodynamic Case Study
No full textA Master of Arts thesis in Teaching English to Speakers of Other Languages by Alaa Tamimi entitled, “The Effects of Emotional Decoding on Eliciting Empathetic Responses in Language Teachers: An Idiodynamic Case Study”, submitted in May 2020. Thesis advisor is Dr. Tammy Gregersen. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).This thesis explores the effects of emotional decoding on enhancing the empathetic responses of a male in-service English second language (ESL) teacher as its case study. Although research has validated the positive implications of empathy in teaching and learning, few studies scrutinize the extent to which the construct of empathy can be facilitated or at best learned and more specifically, how. This intervention case study explores a retrospective empathy enhancement tool necessitating the case study participant to observe video data of himself as he interacts with learners in an authentic ESL classroom and rate his levels of empathy on a moment-to-moment, idiodynamic timescale. The respective rating produces a chart of the dips and spikes of his self-rated empathy. With graph in hand, he then reassesses instances of teacher-student interaction and stops the filmed data in those places where self-reported low levels of empathy had been recorded. At this stage he is requested to pause to read the emotion of the learner during the given interaction and to deliberate on how his response may have changed subsequent to naming the learners’ emotion. The study is the first of its kind to employ an idiodynamic investigation on the power of increasing teacher awareness of learner emotion during classroom interaction. Following the treatment period, the case study participant indicates a heightened awareness of empathy and what an empathic response entails. He also highlights the value of the empathy enhancement process as a potential teacher training tool. This thesis suggests that an idiodynamic approach leads to a retrospective empathy-building process as it encourages the language teacher to self-reflect over their own pedagogical practice in light of naming learner emotion and deliberating more empathic responses and in doing so, a greater awareness of learner emotion is brought to bear.College of Arts and SciencesDepartment of EnglishMaster of Arts in Teaching English to Speakers of Other Languages (MA TESOL