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Comparison of Process-Based Models to Machine Learning Techniques in the Simulation of Flow in Complex Karst Systems: Application on Semi-Arid Case Studies in Lebanon
No full textIn this research, we study the ability of Long Short-Term Memory (LSTM) neu-
ral networks for forecasting karst spring discharge and compare their performance
against traditional process-based hydrological models. Two springs, the Qachqouch
and Assal spring were studied. The models were trained on five years of collected
data and tested on two years. The performance of these models is evaluated based on
standard metrics including Nash-Sutcliffe Efficiency (NSE) and Root Mean Square
Error (RMSE). The results show that LSTM models have comparable performance
relative to complex process-based models. LSTMs require less calibration param-
eters and less preprocessing of data than process-based models. Scores show that
LSTM are able to capture the non linear dynamics of Karst systems. The study
also explores the effect of changing input variables, sequence length and model ar-
chitecture to predict discharge. We notice that longer input sequences generally
enhance model efficacy, especially for capturing delayed hydrological responses typ-
ical of snow-governed systems. Additionally, results highlight that more complex
models having more layers are not better at predicting discharge.
Looking forward, a discussion on the potential of scaling these specific model to
regional ones is made. A proposed sensitivity analysis on input data aims to further
refine model performance. And finally, the potential of these models for studying
long term climate change impact is discussed
أغاني الحضانة اللبنانية
Get PDFThis book is an Arabic nursery rhymes book designated for kids age 2-4
Relationship between University-Bound EFL Learners’ Integrative and Instrumental Motivation and Their Language Proficiency
Get PDFThis study investigates the relationship between the motivation of a cohort of university-bound EFL learners and their language proficiency. The study has a three-fold purpose: (1) to identify whether instrumental or integrative motivation plays a more important role in promoting students toward English language learning; (2) to examine if there is a difference between male and female learners in their motivation (instrumental and integrative) to learn EFL; and (3) to explore if teachers’ instructional strategies are purposefully intended to foster students' instrumental or integrative motivation.
The study employed a mixed methods design that combines qualitative and quantitative data collection to investigate the attitudes and motivations of undergraduate students toward learning English as a second language. The research involved administering a questionnaire adapted from Gardner's Attitude/Motivation Test Battery (AMTB) to a sample of undergraduate students and conducting semi-structured interviews with English instructors to gain more insights into how their instructional strategies affect students' motivation.
A total of 247 (113 males and 134 females) undergraduate students enrolled in one of the English communication skills courses, English 102 course, at the American University of Beirut participated in the study. Also, six instructors who were teaching this course were interviewed.
Collected data from questionnaires were analyzed quantitively using appropriate descriptive (means and standard deviations) and inferential statistics (t-tests, Pearson Product Moment Correlation, and MANOVA) to address the study questions. As for the semi-structured interviews, they were audio recorded, transcribed, and coded for analysis. A thematic analysis approach was used to identify and analyze patterns and themes in the data. The data was organized into meaningful units, and codes were assigned to these units based on the research questions.
The findings of the study revealed that most of the students are instrumentally motivated. They learn the English language for practical reasons like joining a university, finding jobs, higher status in the community, and getting a salary bonus. They also want to fulfill a university language requirement, and, in this study, students want to succeed in English 102 to move to the next level, English 203. Results also showed a positive correlation between instrumental and integrative motivation. However, a negative statistically significant relationship was found between instrumental motivation and EFL proficiency, and there was no statistically significant relationship between integrative motivation and students’ EFL proficiency. Furthermore, gender differences were also identified in this study, where female students had a higher level of motivation than their male counterparts in both types, instrumental and integrative. Finally, teachers’ instructional strategies were not purposefully designed to foster students' instrumental motivation.
The results are discussed and recommendations for further research are included
"ليلى (1923-1925): المجلة النسائية العراقية الأولى: قراءة معمقة في شعار "النهضة النسائيّة
No full textThis thesis offers a systemic study of the contents of Layla, the first women’s magazine published in Iraq between 1923-25. I focus on the relationship between the editorial line in ‘Layla’ and the slogan it raised calling for “the awakening of women”. I argue that the magazine’s founder and editor-in-chief, Pauline Hassoune, sought to curate an editorial content that allows her to both define and legitimize the awakening of women. ‘Layla’ deployed various strategies to achieve these twined goals against the backdrop of opposing social and political forces. In offering a study of the relationship between the content and the slogan, the thesis aims to contribute a study of this pioneering magazine that allows us to situate it in relation to the comparable projects that were cropping up across the region at the time. Furthermore, the project also contributes to our understanding of the history of the ‘women question’ in Iraq
Discovery of Novel Anti-Biofilm Agents from Soil Dwelling Bacteria
No full textBackground: ESKAPE pathogens, as classified by the World Health Organization, pose a significant threat to global healthcare due to their resistance to antimicrobial agents. Among these pathogens, Pseudomonas aeruginosa is particularly troublesome due to its ability to form biofilms, which contribute to antimicrobial resistance and complicate treatment strategies. Developing novel antibiofilm agents capable of selectively targeting biofilm structures without affecting planktonic cells is essential for combating these pathogens. Natural products have long been recognized as valuable sources of bioactive compounds with diverse therapeutic properties. Derived from marine organisms, plants and microorganisms, natural products offer a rich reservoir of chemical diversity, making them attractive candidates for drug discovery efforts. In the past few years, there has been a focus on exploring natural products for drug discovery, prompted by the urgency to address antimicrobial resistance and find new solutions for combating biofilm formation. Given their historical significance and proven efficacy, natural products represent a promising avenue for developing new therapies to combat biofilm-associated infections.
Materials: In this study, we investigated the potential of Streptomyces-derived natural products as antibiofilm agents against Pseudomonas aeruginosa biofilms. A Streptomyces strain (BM9) isolated from Beit Meri soil was cultured in a 6L of medium C, resulting in the production of secondary metabolites. These secondary metabolites were tested for their ability to inhibit biofilm formation of a clinical isolate of Pseudomonas aeruginosa (PAN14) without impacting planktonic cell growth. Bio-guided fractionation techniques were employed to isolate bioactive compounds, which were then evaluated for their efficacy in inhibiting biofilm formation and eradicating preformed biofilms using in vitro assays, including the Inhibition of biofilm formation (IF) and Eradication of Preformed Biofilm (PF) assays. The Minimum Biofilm Inhibitory Concentration (MBIC) of the pure compound was determined in addition to its impact on the MBIC of other antibiotics when combined together. Moreover, some physiological, phenotypic and genomic characterization of the bacterial strain BM9 were assessed.
Results: After the liquid-liquid partitioning, Hexane, Chloroform fractions showed significant anti-biofilm activity against Pseudomonas aeruginosa. Subsequent fractionation led to the isolation of a pure compound, exhibiting potent antibiofilm activity with a Minimum Biofilm Inhibitory concentration (MBIC) of 32 µg/mL against preformed biofilms of PAN14 without any effect on planktonic cells. This active compound showed a synergistic effect with two clinically used antibiotics: Gentamicin and Colistin. Furthermore, after the genomic analysis, BM9 was identified as Streptomyces galilaeus. These findings highlight the potential of Streptomyces-derived natural products as effective antibiofilm agents and emphasize the importance of evaluating their safety profiles for future therapeutic development.
Conclusion: The isolated compound from Streptomyces galilaeus BM9 demonstrates promising antibiofilm activity against P. aeruginosa biofilms and warrants further investigation for therapeutic development. This study highlights the potential of natural product-derived compounds as effective antibiofilm agents and underscores the importance of safety evaluation for future clinical applications. Further elucidation of the mechanism of action and additional purification of bioactive compounds from BM9 extract are essential for advancing this research toward clinical translation
Housing, Land and Property Rights: a main determinant for Syrian Potential Returnees
Get PDFThe Assad Regime Anti-Normalisation Act of 2023, sanctioned by the U.S. House of Representatives, extends the sanctions outlined in the Caesar Act on Syria until December 31, 2032. With substantial bipartisan backing, this legislation aims to impede any attempts at normalizing relations with Bashar al-Assad's administration. It also addresses pressing concerns such as the diversion of aid and violations of Housing, Land, and Property (HLP) rights. HLP rights violations encompass property confiscations, laws obstructing property restitution, and coercive tactics by security forces, which severely impede the repatriation of refugees and internally displaced persons (IDPs). The Syrian government's emphasis on real estate laws not only facilitates demographic manipulation but also bolsters support for regime loyalists. Until a political resolution is reached, numerous Syrians encounter formidable obstacles hindering their return to their homeland.The Assad Regime Anti-Normalisation Act of 2023 was decisively approved by a substantial majority in the U.S. House of Representatives, with 389 votes in favor and 32 against. The primary objective of this act is to prolong and broaden sanctions against Syria until 2032. This legislative measure underscores bipartisan consensus on the imperative to isolate Bashar al-Assad's administration and addresses critical issues such as aid misdirection and violations of Housing, Land, and Property (HLP) rights. These HLP transgressions pose significant barriers for Syrian refugees and internally displaced individuals seeking to repatriate. The bill now awaits the endorsement of the Senate and the President to be enacted as law
Measuring Fiscal Sustainability in the MENA Region Using a Time-Varying Fiscal Reaction Function
Get PDFOver the past few decades, countries of the Middle East and North Africa (MENA)
region have faced several economic and political challenges such as plummeting oil
prices, currency devaluations, political instability, and several refugee crises in sev eral countries. Even prior to the onset of the COVID-19 pandemic, several studies
revealed that the MENA region suffers from poor governance which leads to higher
levels of debt as a share of the output. Consequently, addressing the sustainability
of this mounting debt is a pressing issue for the region. As such, the escalating debt
situation in the MENA region demands a comprehensive analysis. Against this
background, this thesis evaluates the sustainability of public debt in some coun tries of the MENA regions, particularly Bahrain, Egypt, Jordan, Kuwait, Morocco,
Oman, Qatar, Saudi Arabia, Tunisia, and the United Arab Emirates by employing a
state-space model with time-varying parameters. The thesis endeavors to tackle how
the trajectory of debt sustainability evolved in MENA region economies throughout
different time periods and what economic criteria determine the threshold of public
debt sustainability
Leveraging AI for Confident Classification and Prioritization of Intrusion Detection System Alerts
No full textThe increasing complexity and volume of cybersecurity alerts significantly challenge threat detection efforts, particularly within Security Operations Centers (SOCs), where the high rate of false positives can obscure real and dangerous threats. This burden not only strains resources but also increases the risk of overlooking genuine security breaches. Leveraging advanced machine learning techniques, particularly Large Language Models (LLMs), this thesis introduces a novel methodology aimed at enhancing the precision of alert classifications from Windows endpoints’ security logs.
This study extracted approximately 700 false and real threat cases from a real enterprise network. The proposed approach involves creating an Execution Graph for each alerting Windows process, which is then processed by a "Graph Contextualizer" block. This block transforms complex process interactions into structured, analyzable formats suitable for training and inference in large language models.
The transformed data points are subsequently fed into several locally fine-tuned LLMs designed to classify the alerts accurately. Preliminary evaluation of this pipeline shows excellent metrics, achieving high levels of precision and recall, thereby substantiating the effectiveness of our approach. The methodology not only improves the operational efficiency of SOCs by reducing the investigative overhead of false threats and assisting in the detection of real threats but also contributes significantly to the broader field of cybersecurity, offering a scalable model for integrating machine learning into existing security infrastructures
Dimensions of Religiosity as Predictors of Body Image Dissatisfaction and Disordered Eating in a University Sample in Lebanon
Get PDFDisordered eating is recognized as a significant risk factor for developing clinical eating disorders, which can pose severe mental and physical health risks and may be life-threatening. The risk of eating disorders is particularly high during late adolescence and early adulthood, underscoring the importance of identifying both protective and risk factors associated with disordered eating for this age group. Although sociocultural risk and protective factors of disordered eating have been corroborated, the role of religiosity has been overlooked, especially within the Lebanese context. The present study examined the unique role of multiple dimensions of religiosity, including religious orientation (intrinsic and extrinsic), attachment to God (anxious and avoidant), religious coping (positive and negative), body sanctification, and body acceptance by God in relation to body image dissatisfaction and disordered eating in a sample of undergraduates in Lebanon. The role of body image dissatisfaction as a mediator was also explored. Results showed that religious orientation, attachment to God, and religious coping did not have significant relationships with body image dissatisfaction and disordered eating beyond the bivariate level. Multiple regression analyses showed that nontheistic body sanctification and body acceptance by God significantly negatively predicted body image dissatisfaction while considering the effects of established factors including gender and body mass index, and body acceptance by God significantly negatively predicted disordered eating while considering the effects of gender, socioeconomic status, and body mass index. A mediation analysis showed that body image dissatisfaction mediated the relationship between body acceptance by God and disordered eating. The results provide evidence of the protective role of nontheistic body sanctification and body acceptance by God in relation to body image and disordered eating outcomes among university students in Lebanon. Findings are discussed within the context of existing literature, and practical implications and recommendations are offered in consideration of the limitations of the present study
Biological Activities of Halodule uninervis Ethanolic Extract
No full textHerbal medicine has been gaining special interest as an alternative treatment for various diseases, with plant-derived compounds showing promising antioxidant, anti-inflammatory, and anticancer activities due to their diverse bioactive metabolites and unique characteristics. Halodule uninervis, a seagrass from the family Cymodoceaceae, is known for its rich array of bioactive metabolites that provide it with a range of pharmacological properties. However, some biological activities of H. uninervis remain unexplored. This work investigates, for the first time, the anticancer activity of H. uninervis ethanolic extract (HUE) against triple-negative breast cancer (TNBC), its anti-inflammatory effect on macrophages, and its potential use in the green synthesis of gold nanoparticles (AuNPs). Our results indicated that HUE is rich in diverse bioactive metabolites with significant antioxidant and anticancer properties. In the MDA-MB-231 TNBC cell line, HUE targeted key cancer processes such as cell proliferation, adhesion, migration, invasion, and angiogenesis. We found that HUE-mediated anti-proliferative and anti-metastatic effects were associated with the inhibition of the proto-oncogenic STAT3 signaling pathway. Additionally, HUE inhibited the inflammatory response in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages by decreasing the expression of pro-inflammatory enzymes (iNOS and COX-2) and cytokines (IL-6 and TNF-α). The anti-inflammatory potential of HUE was associated with the suppression of NF-kB, STAT3, and p38 MAPK pathways. Finally, HUE was successfully used for biosynthesis of AuNPs. Characterization of the biogenic AuNPs revealed the formation of small, spherical nanoparticles, which are crystalline in nature and stable at high temperatures. These AuNPs exhibited potential anticancer activity against MDA-MB-231 breast cancer cell line by inducing apoptosis. Taken together, our results highlight the potential of HUE as a valuable source for developing novel therapeutic agents with anticancer and anti-inflammatory activities