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Maintaining the Cartilage Phenotype of Late Passage Chondrocytes Using Salidroside, TGF-β and Sulfated Alginate for Cartilage Tissue Engineering Applications
No full textCartilage self-repair following injury or osteoarthritis is limited due to its low regenerative capacity, avascular and aneural nature. Therefore, a promising treatment of cartilage injury and disease may involve engineering cartilage tissue in vitro by combining cells (e.g. chondrocytes), scaffolds (e.g. alginate sulfate (AlgSulf)), and signals (e.g. Salidroside and TGF-β). Autologous chondrocyte transplantation (ACT) is one of the most commonly used techniques for the treatment of cartilage defects. In ACT, chondrocytes are expanded in vitro till passage 3 or 4 and are then injected in the defect site. However, late passage chondrocytes undergo a process called dedifferentiation whereby cells lose their phenotype assuming a fibroblastic phenotype, thereby secreting type I collagen (Col1) instead of type II collagen (Col2) among other key changes. We have previously shown that chondrocytes encapsulated in three-dimensional (3D) biomimetic sulfated polysaccharides such as AlgSulf exhibit increased proliferation while maintaining their cartilage phenotype. The effects of alginate sulfate on cell growth and matrix deposition may be linked to enhanced binding of growth factors such as TGF-β. Moreover, Salidroside was found to upregulate the expression of cartilage specific genes such as Col2, aggrecan (Acan) and Sox9, while down-regulating the expression of the fibroblastic gene Col1 by acting on the TGF-β/Smad3 signalling pathway. This thesis aims to study the effect of treatment of P2 and P4 chondrocytes seeded on AlgSulf 2D films with Salidroside, TGF-β and their combination. Therefore, P2 and P4 chondrocytes were seeded on 2D films of AlgSulf of three different degrees of sulfation (DS=1, 1.5 and 2), in the presence or absence of Salidroside, TGF-β and their combination, and then, cell viability, proliferation, phenotype, and collagen secretion were assessed. Trypan Blue was used to study cell proliferation, while a live/dead assay was performed to assess cell viability. Quantitative real time PCR and Western Blot were also performed to evaluate the expression and synthesis of chondrogenic markers. The proliferation assay showed that a combination of Salidroside and TGF-β on AlgSulf films of DS=2 (AlgSulf2.0) resulted in the highest chondrocyte proliferation compared to all other treatments (p<0.0001). Under this same treatment, chondrocytes exhibited a round morphology when observed using Ethidium homodimer and Calcein AM, and displayed the highest levels of Col2A1, Acan and Sox9, while down-regulating the expression of Col1 and MMP13 (p<0.0001). The Western Blot also showed a prominent expression of Col2 and downregulation of Col1 when tested on P2 chondrocytes subjected to Salidroside on AlgSulf2.0. Therefore, this work shows that the treatment of chondrocytes seeded on AlgSulf2.0 films with a combination of Salidroside and TGF-β significantly promoted the proliferation of late passage chondrocytes while preserving their phenotype. The results of the current study may therefore be used in cartilage engineering applications
The Association between Overprotective Parenting, Parental Perceptions of Child Vulnerability and the growth and Development of Children with Congenital Heart Disease
No full textBackground: Congenital Heart Disease (CHD) is the most prevalent childhood birth defect, leading to health concerns in growth and development post-surgery. Parents mostly shoulder the responsibility for post-hospitalization care. The chronic nature of caring for a child with CHD induces significant stress, fostering perceptions of the child as highly vulnerable and resulting in overprotective behaviors. These behaviors could restrict the child's developmental opportunities, affecting their overall growth and development.
Purpose: The purpose was to investigate the association between parental perceptions of child vulnerability, overprotective parenting, and growth and development of children with CHD.
Methods: The study employed a cross-sectional, comparative design. The total sample included 186 [93 CHD and 93 healthy controls] parents and their child aged 1-5 years. Data on parenting practices were gathered using the Child Vulnerability Scale and Parental Protection Scale. Child development was examined using the Ages and Stages Questionnaire-3. Growth and other clinical variables were gathered from the medical records. Data were analyzed using descriptive statistics, correlational and mediation analyses.
Results: CHD parents exhibited higher overprotective parenting (p = 0.008) and perceived their child as more vulnerable (p < 0.001) than healthy controls. In CHD, parental perception of child vulnerability was associated with worse gross motor skills (p = 0.010) and problem-solving development (p = 0.011), while among the controls, overprotective parenting was negatively associated with height (p = 0.027) and weight (p = 0.003). The path analyses revealed direct effects but no mediating or moderating effects of perceived child vulnerability and overprotectiveness on growth and development of the child with CHD. Higher parental perceptions of child vulnerability were associated with lower height (b1= -0.253, 95% CI: -0.397 to -0.087) and weight (a2= -0.098, 95% CI: -0.195 to 0.003). The higher the parental stress, the greater the perceptions of child vulnerability were (d1= 0.108, 95% CI: 0.058 to 0.160) and the worse communication skills of the child (cʹ2= -0.250, 95% CI: -0.422 to 0.091). Higher education level of the parents was associated with less perceptions of child vulnerability (a3= -4.099, 95% CI: -6.426 to -1.854), better fine motor development (cʹ3=0.245, 95% CI: 0.090 to 0.418) and less overprotective parenting (d3=-4.583, 95% CI: -7.726 to -1.341). Higher perceptions of child vulnerability showed a trend with lower personal-social development (b1= -0.378, 95% CI: -0.803 to 0.046).
Conclusion: Healthcare providers may need to consider the diverse parental and child factors identified to initiate interventions aimed at parenting practices, realistic perceptions of their child’s condition, and reducing parental stress to optimize growth and development in Lebanese children with CHD.
Currency and Banking Crisis in Developed and Emerging Economies
Get PDFFinancial crises, encompassing banking and currency disruptions, are pivotal events with far-reaching implications for global economic stability. This research investigates the nuanced dynamics of banking and currency crises in both developed and developing economies, aiming to discern distinctive patterns, risk factors, and interrelationships between these crisis types across different economic contexts. Leveraging a comprehensive crisis database covering 206 countries and a myriad of macroeconomic indicators from reputable sources, the study employs a panel logit model to analyze the determinants and likelihood of crises occurrence.
The analysis unveils a higher prevalence of banking crises in developing economies, attributable to macroeconomic vulnerabilities such as slow GDP growth and elevated inflation rates. In contrast, developed nations exhibit greater resilience to currency crises, characterized by robust monetary mechanisms and exchange rate frameworks. However, external shocks and global economic fluctuations serve as common triggers for currency disturbances across both economic groups.
Moreover, the study elucidates the intricate connections between banking and currency crises, revealing a temporal sequence where banking crises often precede or coincide with currency disturbances. This interconnectedness underscores the complexity of financial ecosystems and underscores the imperative of integrated risk management strategies.
The findings offer valuable insights for policymakers, financial institutions, and stakeholders in formulating proactive measures to enhance financial resilience and mitigate the risks associated with banking and currency crises. By understanding the distinct dynamics and risk factors influencing crises in developed and developing economies, this research contributes to a deeper comprehension of global economic stability and resilience strategies
Federated Machine Learning and TinyML Inference for Crop Disease and Pest Classification on Smartphones
Get PDFAs the agricultural industry undergoes a technological revolution, the integration of machine learning (ML) and mobile technologies emerges as a promising solution to address crop disease management efficiently. In this thesis, we present a novel approach combining federated learning (FL) and TinyML inference for crop disease classification on smartphones. Our research encompasses the development of a web application for dataset collection, complemented by a mobile application tailored for farmers. Through rigorous training, we produced multiple ML models, each specialized in detecting diseases across different plant types. These models were subsequently hosted for offline use, empowering farmers with real-time disease identification capabilities directly on their smartphones. Leveraging FL techniques, our solution ensures adaptability and scalability, crucial factors in the agricultural domain. Furthermore, employing TinyML inference enables efficient model execution on resource-constrained devices without compromising accuracy. Evaluation results demonstrate an impressive average accuracy of 98% across all deployed models. This framework represents a significant step forward in democratizing access to advanced agricultural technologies, enhancing crop disease management, and contributing to global food security
THE ASSOCIATION BETWEEN SLEEP QUALITY AND ARRHYTHMIA SYMPTOMS IN PATIENTS WITH ATRIAL FIBRILLATION IN LEBANON
Get PDFBackground: Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia globally causing a major burden on many quality of life determinants, including sleep quality. Although there is extensive evidence showing reduced sleep quality among AF patients, there are limited data on the predictors of poor sleep among this population, and how specific AF symptoms correlate with poor sleep quality.
Aims: This study aimed to describe sleep quality in a sample of AF patients in Lebanon, examine the associations between sleep quality and the number and bothersomeness of specific AF symptoms, and determine the predictors of reduced sleep quality among these patients.
Method: This was a cross-sectional descriptive/correlational study conducted at the cardiology clinics of the AUB Medical Center. One hundred and forty-four AF patients were recruited, assessed for their heart rhythm, and asked about their sleep quality and AF symptoms through individual interviews, using the Pittsburgh Sleep Quality Index (PSQI) and Patient’s Perspective of Arrhythmia Questionnaire (PPAQ). Clinical data were retrieved from the medical records.
Statistical Analysis: Descriptive analyses were conducted to describe the sample demographics, sleep quality, and other characteristics. Pearson r correlation tests were run to determine associations between AF symptoms (frequency/bothersomeness) and sleep quality. In addition, t tests and ANOVA were conducted to measure the association between the sleep quality index, demographic and clinical variables. Multivariate linear regression analyses were conducted to determine the predictors of sleep quality among AF patients.
Results: The majority of the sample suffered from poor sleep quality (91%). The most prevalent AF symptoms were fatigue, dyspnea, heart flutter and headache whereas the most bothersome symptoms were fatigue, chest pressure and dizziness. Most symptoms and their bothersomeness were significantly associated with sleep quality. The number of AF symptoms, bothersomeness of symptoms, intake of caffeine before bedtime, and history of COPD were independent predictors of poor sleep quality.
Conclusions: Health care professionals need to manage the symptoms of AF patients and regularly assess their quality of sleep. Education to avoid caffeine intake late in the day is also recommended. Future studies are needed to test the effect of symptom management interventions on sleep quality in AF patients.
National Renewable Energy Action Plan-Local and Global Assessment
Get PDFWithin the effects of global warming and climate change, there comes renewable energy, a solution for long-term growth and sustainability. Countries worldwide are experiencing the negative impacts of global warming and climate change which are caused by greenhouse gas (GHG) emissions. Moreover, the instability in oil prices and the talks about fossil fuel running out sometime in the future raises thoughts about finding other alternatives. Luckily, the burning of fossil fuels to produce energy can be replaced by greener and cleaner energy alternatives. Renewable energy is critical to long-term growth and sustainability. Clean technologies provide significant benefits in terms of economic growth, financial benefits, and environmental benefits, in addition to energy sector security, strengthening the sustainability of the energy sector and other key sectors globally and specifically in Lebanon. Furthermore, renewable energy is recognized as the primary component for mitigating the detrimental effects of the country's power sector crisis and due to the rise in fuel prices, electricity bill, and currency depreciation
Exploring a Global Research Agenda on Civic Engagement: Lessons From a Decade of Feminist Mobilization in the Arab Region
Get PDFThe Arab uprisings of 2011 marked a pivotal moment in the Middle East and North Africa (MENA), bringing to the forefront issues of political oppression, economic disparity, and social injustice. In the aftermath, the region faced a complex array of challenges, from sectarian tensions to authoritarian resurgence. Amidst this turmoil, feminist activists persisted in their advocacy for gender equality and women’s rights. This report examines the strategies employed by feminist civil society groups in Egypt, Jordan, Lebanon, and Tunisia over the past decade. Through comparative case studies, it analyzes the evolution of mobilization efforts, coalition-building, and engagement with decision-makers. The three case studies include (1) challenges and strategies in nationality laws reform in Jordan and Lebanon, (2) feminist campaigns against gender-based violence (GBV) in Egypt and Lebanon, and (3) dynamics of LGBTQIA+ movements in Tunisia and Lebanon. By uncovering the factors influencing the success or failure of these efforts, the study aims to provide insights for future advocacy endeavors and offer practical recommendations to advance gender equality in the MENA region.Arab Reform InitiativeInternational Development Research Centr
A Blockchain Framework Targeting Unethical Prescription Pattern of Incentive Based Prescription: Application and Proof of Concept
Get PDFIn the realm of medicine and the increasing unethical behaviors happening resulting in different medical crises has made the demand for a better transparent trusted mediator that can achieve the objective. Blockchain has been discussed and used as a potential solution for different financial and healthcare management, due to its ability to provide a trusted median between parties, transparency, and traceability. These features are important to provide a sustainable healthcare system that delivers solutions to patients and does not create new medical crises. We provide an analytical comparison between different solutions that have been implemented to resolve the problem. As well as presenting, providing, and validating our solutions capability in mitigating and limiting the unethical practices being done in the field
Reconfigurable Wideband Circularly Polarized Antenna Array for 5G mm-Wave Applications
No full textIn this thesis, a novel reconfigurable wideband circularly polarized antenna array structure designed for millimeter-wave 5G applications at Ka-band is proposed. The system offers dynamic polarization control and the ability to switch between right-hand circular polarization (RHCP) and left-hand circular polarization (LHCP), enabling enhanced communication flexibility. The design is realized through the implementation of a 2x2 antenna array structure as a radiating element, a 90° hybrid coupler, a 180° rat-race coupler with cross-over, and an SPDT switch. The primary structure of the patch antenna is based on two dual-fed microstrip lines at the center of the orthogonal edges of the patch antenna. A four-element antenna array based on the structure of the single antenna element is designed to enhance the gain. A quadrature 90° -3dB hybrid coupler is incorporated to evenly split the power and achieve a 90° phase difference between the adjacent antenna elements in the antenna array. In addition, to realize an overall reconfigurable structure with dynamic feeding, a 180° coupler with crossover is utilized to achieve a 180° between two diagonally opposite ports of the hybrid coupler. The overall final structure is reconfigured to attain RHCP or LHCP through the activation of one of two ports. An overall impedance bandwidth of 5 GHz between 30 GHz – 35 GHz, with an overlapping axial-ratio bandwidth of 3.4 GHz between 30 GHz – 33.4 GHz, and a maximum peak gain of 8dBic is achieved
Heavy Metal Contamination in Agricultural Soils in Lebanon: Effect of Soil Types on Hyperspectral Imaging
No full textHeavy Metals (HMs) pollution in agricultural soils has become of great concern in Lebanon. Detailed and accurate spatial soil information became essential for environmental risk assessment. Hyperspectral remote sensing for the detection of heavy metal contamination in soils and vegetation has been widely studied as an alternative technique to traditional heavy metals measurement methods such as atomic absorption spectrometry (AAS) and was found to be cost-effective, efficient, and less time-consuming. However, the potential of remote sensing data in detecting HMs contamination in soils has not been explored and tried in Lebanon. In addition, factors affecting the use of hyperspectral imaging (HSI) in soil contamination detection were not thoroughly studied. This study investigated the impact of the Lebanese agricultural soil types on HSI at different contamination levels of Cadmium (Cd) and Nickel (Ni). Clay, silty, and sandy soils were tested being the three most prevalent Lebanese soil types. Soil samples were contaminated with Cd and Ni, considering the addition of one metal at a time, at different contamination levels and detection of the contamination was performed using AAS and HSI. Data from the AAS served as ground truth to confirm the efficiency of HSI in heavy metals detection and quantification. To fulfill the aim of the study, four artificial intelligence (AI) prediction models – partial least square regression (PLSR), support vector regression (SVR), neural networks (NN), and convolutional neural networks (CNN) – were tested and compared. Nonetheless, model performance statistics showed that the SVR and CNN performed better, providing high accuracy for almost all soil types. Clayey, silty, and sandy soils achieved 85%, 83%, and 79% accuracy respectively for Ni and 93%, 93.1%, and 92.5% for Cd contamination prediction using SVR. As for the CNN regressor, the prediction of HMs in the silty soil achieved 89.9% and 94.9% for Ni and Cd respectively and sandy soils achieved up to 87.2% and 93.8% accuracy for Ni and Cd respectively. Clay soil represented higher accuracy with the NN-based model achieving 93% and 95% for Ni and Cd respectively. The developed SVR and CNN models were then validated with newly contaminated soil samples. A particularly good fit was obtained with values of R2 ranging between a minimum of 0.79 for sandy and 0.81 for the clayey soil in predicting Ni content, and between 0.82 and 0.92 for sandy and clayey soil respectively describing Cd metal for SVR-developed models. CNN models also excelled in their validation results representing a range of R2 between 0.82 and 0.841 for Ni metal, and between 0.911 and 0.94 for Cd-developed models.
The results further revealed that soil type does have a strong impact on the reflectance of the HSI, affecting the reflectance intensity and spectral shape, in terms of physical properties, and representing different absorption features, which are generally related to the specific chemical properties of each soil type. This was also highlighted and justified by validating the same SVR and CNN-developed models but this time with different soil type data. The results showed that each soil type has its specific properties and cannot predict data related to other soil types (R2 ranged between 0.107 and 0.242 for SVR models and between 0.11 and 0.26 for CNN models).
The overall results indicated that the hyperspectral imaging technique can be used for HM detection in soils, and information about Lebanese agricultural soil can be accessible with relatively few human and financial resources