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Gender Bias Detection: Examining the Implicit Bias Inherited by ChatGPT
Get PDFIn this drastically evolving digital era, textual content production heavily relies on Large Language Models. These models are prone to inherit and thus propagate various forms of stereotypes and gender bias from their training corpus, which has harmful consequences on the worldwide population, such as loss of human potential, aggressive behaviors, biased mental imagery, and unfair labor force participation. Therefore, this thesis focused on evaluating gender bias in the responses of one of the most recent and popular LLMs, ChatGPT. We examined occupational and semantic bias in three common tasks of ChatGPT as well as in the embedding task of Ada-V2 model. After that, we finetuned ChatGPT on bias detection for three types of bias: sexism, dehumanization, and generic bias. The finetuned versions outperformed the original model as well as other popular LLMs in bias detection. We were also able to highlight two major weaknesses in ChatGPT’s learning capabilities as well as reduce the gender gaps in the model’s responses. This research built a strong basis for future work to ensure the safe and valuable use of recent AI tools like ChatGPT
Choreographing Neural Rhythms: Intrinsic and Synaptic Modulations of Temporal and Stereotyped Neural Sequence Generation in the Premotor Cortex of Songbirds
No full textLearned sequential behaviors are captivating brain patterns; however, their underlying neural mechanisms are not well understood. Birdsong is a prominent model to study such behavior particularly because juvenile songbirds progressively learn from their tutors and by adulthood are able to sing stereotyped song patterns. We studied the premotor nucleus HVC at a nexus of multiple pathways contributing to song learning and production. The HVC consists of multiple classes of neuronal populations, each that has its own cellular, electrophysiological and functional properties: basal ganglia – projecting (HVCX) neurons, forebrain - projecting (HVCRA) neurons, and interneurons (HVCINT). During singing, a large subset of motor cortex analog-projecting HVCRA neurons emit a single 6-10 ms burst of spikes at the same time during each rendition of song, a large subset of basal ganglia-projecting HVCX neurons fire 1 to 4 bursts that are similarly time locked to vocalizations, while HVCINT neurons fire tonically at average high frequency throughout song with prominent modulations whose timing in relation to song remains unresolved. This opens the opportunity to define models relating explicit HVC circuitry to how these neurons work cooperatively to control learning and singing. Despite the fundamental importance of unveiling the neural mechanisms behind temporal sequence generation in general, and birdsong vocalizations in specific, very little had been done at the experimental and computational levels. In this thesis, we developed conductance-based Hodgkin Huxley models for the three classes of HVC neurons (based on the ion channels previously identified pharmacologically) and connected them in several physiologically realistic networks (based on pharmacologically identified glutaminergic and GABAergic connectivity) via different architecture patterning scenarios with the aim to replicate their in vivo firing patterning behaviors. We are able through these networks to reproduce the in vivo behavior of each class of HVC neurons as shown by the experimental recordings. The different networks unveiled key intrinsic and synaptic processes that modulate the sequential propagation of neural activity (continuous or punctate) in the HVC by highlighting important roles for the T-type Ca2+ current, Ca2+-dependent K+ current, A-type K+ current, hyperpolarization activated inward current, as well as GABA and AMPA synaptic currents in governing important neural mechanisms for sequence propagation, like post-inhibitory rebound bursting in HVCX, mono-synaptic HVCX to HVCRA excitatory connectivity, different classes of interneurons (phasic and tonic), microcircuit architecture patterning in encoding syllables or sub-syllabic segments, among others. The result is an improved characterization of the HVC network responsible for song production in the songbird
حرب غزة بمنظار المسألة السنیة المشرقیة الراھنة
No full textيبحث هذا البحث في تأثير النزاعات الإقليمية والطائفية في منطقة الشرق الأدنى، مع التركيز على النزاع السني والشيعي في غزة. يُعنى التحليل بتأثيرات التهجير وتدمير الهوية العرقية والدينية، وكيف ساهمت هذه العوامل في تعزيز الصراعات الإقليمية. يتناول البحث أيضًا دور الاستعمار والقومية العربية في تشكيل هذه النزاعات
The Role of Remittances in Hampering Economic Growth in Lebanon
Get PDFRemittances from migrants not only represent one of the most stable sources of foreign exchange earnings but have also been the primary capital inflow for Lebanon throughout much of the post-war period. Despite their significant role, limited empirical studies exist on the impact of these remittances on economic growth in Lebanon. This study aimed to address this gap by investigating the effects of remittances on Lebanon's public debt in foreign currency between 2002 and 2022. The ARDL estimation technique was employed to explore the long-term relationships among the chosen variables. The findings revealed a significant positive long-term association, indicating that remittances substantially influenced Lebanon’s public debt dynamics. The analysis also identified important short-term effects of central bank foreign currency reserves on public debt. Furthermore, the study highlighted a noticeable misallocation of remittances into unproductive sectors, suggesting a crowding out effect where remittances failed to enhance productive investment and economic capacity, thereby undermining long-term economic development and compromising the growth benefits of these foreign inflows.
مصرف لبنان: تحليل جنائي
No full textتقرير التدقيق من Alvarez & Marsal على مصرف لبنان (BdL) للفترة 2015-2020 هو أول تقييم مدقق خارجي منذ تأسيس مصرف لبنان في عام 1964. يكشف التقرير عن سوء إدارة مصرف لبنان تحت سيطرة الحاكم وحده، ممارسات محاسبية تعسفية وخسائر مخفيّة.
أدت الهندسة المالية الخاطئة لمصرف لبنان إلى عجز بقيمة 60 مليار دولار في احتياطات العملات الأجنبية وانهيار مصرفي لاحق، تفاقم بسبب فشل الحكومة في الإشراف وسوء إدارة السيولة من قبل البنوك. على الرغم من الأزمة المالية المستمرة، مع تجميد الودائع المصرفية وعدم محاسبة المسؤولين، يقترح التقرير أن التعافي المالي ممكن من خلال إصلاحات قانونية ومعيارية فورية، يقودها قيادة سياسية مسؤولة.النسخة الإنجليزية: Banque du Liban: A Forensic Analysis
http://hdl.handle.net/10938/24540يتضمن مراجع ببليوغرافية (صفحة 24)يكشف تقرير التدقيق من Alvarez & Marsal على مصرف لبنان (BDL) خلال فترة 2015-2020 عن سوء إدارة واسع النطاق وممارسات مالية غير قانونية. استخدم مصرف لبنان، بقيادة الحاكم وحده، محاسبة تعسفية، وأخفى خسائر متزايدة، وانخرط في معاملات مشبوهة. يسلط التقرير الضوء على خسائر كبيرة، حقوق ملكية سلبية، وعجز في احتياطات العملات الأجنبية (FX) بقيمة 60 مليار دولار بحلول عام 2019 بسبب الهندسة المالية المكلفة. أدى ذلك إلى انهيار مصرفي حاد، تفاقم بسبب سوء إدارة السيولة من قبل البنوك وفشل الحكومة في الإشراف. يُعتبر التعافي ممكناً من خلال إجراءات قانونية ومعيارية عاجلة، تتطلب تغييراً في القيادة السياسية والمساءلة
Survey and Development of an Integrated Disease Management Strategy for Banana Panama Wilt Disease in Lebanon
Get PDFPanama wilt disease, caused by Fusarium oxysporum f. sp. cubense Tropical Race 4 (Foc TR4), is a significant threat to banana production worldwide, leading to severe yield losses in both commercial and local banana varieties. The pathogen was first identified in Lebanon in 2013. Despite its global impact, there has been limited practical research on the spread and management of banana Fusarium wilt in Lebanon. This study had three primary objectives: (1) to determine the distribution and significance of the disease in South Lebanon, (2) to evaluate the antagonistic activity of selected biocontrol agents, and (3) to assess an integrated management approach to mitigate the disease. First, a survey was conducted across 87 sites in South Lebanon to determine the current spread of the disease. A total of 260 plant samples, including both asymptomatic and symptomatic plants exhibiting wilt symptoms, were collected. The results indicated that 30% of the fields were infested with Foc TR4, demonstrating the widespread occurrence of the disease in the coastal area. Second, laboratory tests using a dual culture assay were performed to evaluate the antagonistic activity of seven Trichoderma spp. strains against Foc TR4. The results revealed that all Trichoderma isolates significantly reduced the mycelial growth of the pathogen, with T. viride strain T24 showing the highest inhibition, reducing growth by 74%. Third, an integrated management approach was evaluated through both pot experiments with artificially inoculated soil and a large-scale field trial. The field experiment, conducted in South Lebanon using a completely randomized design with four replications, involved four banana varieties: Baladi, Canarian, Grand Nain, and GCTCV2 18. The former two varieties were subjected to five treatments: a control, Trichoderma harzianum, Bacillus amyloliquefaciens (Novo Treat®), Pythium oligandrum (Polyversum®), and a combination of Bacillus subtilis + Pseudomonas putida (Fulzyme®). Disease severity assessments were based on both external and internal disease symptoms. Among all varieties tested, GCTCV 218 demonstrated the highest tolerance to Foc TR4, showing the lowest disease severity index (33%) and the highest bunch weight (31 kg). In both the Baladi and Canarian varieties, T. harzianum significantly reduced the Foc TR4 disease index, decreased endophytic Fusarium infections, and enhanced yield. In the pot experiment, T. harzianum also significantly reduced the disease index compared to the control treatment for both varieties. Fulzyme® was identified as the second most effective treatment. Given the widespread presence of the disease in South Lebanon, an integrated management approach is recommended to contain further spread and minimize damage in infested orchards. Strict sanitation measures should be implemented within and between fields. The use of tolerant or resistant varieties like GCTC V218 is advisable, along with an integrated crop management approach, including the use of biocontrol agents such as Trichoderma, B. subtilis, and P. putida. Considering the microclimate and edaphic variations between different regions, further local studies on the management of the disease are recommended
Repurposing Piroxicam Enhances the Antineoplastic Effects of Docetaxel and Enzalutamide in Prostate Cancer Cells In Vitro
No full textIntroduction:
Ranked second most diagnosed cancer and the fifth leading cause of cancer-related deaths
among men, prostate cancer (PCa) constitutes a major medical health issue. Despite the fact that many
therapeutic approaches exist against PCa, most cases often develop into a more advanced and lethal
stage known as metastatic castration-resistant prostate cancer (mCRPC). Hence, unfolding new
therapeutics to treat and manage PCa is of crucial importance. Drug repurposing is a growing research
field based on using previously approved drugs with known pharmacokinetic and pharmacodynamic
characteristics, for indications other than their traditional ones, like cancer. Non-steroidal anti-
inflammatory drugs (NSAIDs) have been studied as anti-neoplastic agents in several malignancies.
Objective:
In this study, we are interested in assessing the anti-tumorigenic effects of the NSAID
Piroxicam (PXM), alone and in combination with conventional therapies, on two PCa cell lines in vitro.
Material and Methods:
PXM, alone and in combination with conventional therapies (docetaxel and enzalutamide), will be tested on two cell lines
established in our laboratory that have the same defined Pten‑/‑TP53‑/‑ background representing two
different stages of PCa disease: PLum-AD (androgen-dependent) and PLum-AI (androgen-
independent). MTT assay will be performed to screen the cytotoxic effect of a wide battery of PXM
concentrations on those two cell lines. Then, trypan blue exclusion assay will be done to study PXM’s
effect on cell viability. Afterwards, wound healing will be used to study the ability of PXM in inhibiting
cell migration. Furthermore, 3D-sphere formation assay will be performed to assess the effect of PXM
in targeting PCa progenitor/stem cells.
Results/anticipated results:
MTT preliminary results showed that PXM has a dose-dependent cytotoxic effect and a synergistic effect with both conventional drugs on PCa cells.
Similar effects are obtained using trypan blue exclusion method. In addition, PXM inhibits and synergistically increases the effect of docetaxel and enzalutamide on migratory index of PCa cells and the sphere-forming abilities of cells.
Conclusion:
NSAIDs represent a potential candidate to be repurposed against PCa. We expect PXM, an
FDA-approved drug, to show anti-cancer effects against PCa cells including progenitor cells, and to
enhance the effect of already existing PCa treatments, overcoming resistance obstacles limiting
conventional treatments leading to a more efficient management of the disease
Investigating The Dynamic Interaction Between Cx43 and TET2 in Inflammatory Bowel Disease and Colorectal Cancer
Get PDFInflammatory Bowel Disease (IBD) is comprised of two disorders, Ulcerative Colitis and Chron’s disease; both result in chronic inflammation of the gastrointestinal tract accompanied by repetitive acute inflammatory flare ups. Statistically this has shown to significantly increase the risk for the development of colorectal cancer (CRC). Gap junction proteins such as Connexin 43 (Cx43) are thought to be tumor suppressor genes and have been observed to be altered in pathological conditions including IBD and CRC. There is a current interest in studying the role of epigenetic mechanisms such as DNA methylation in the context of disease. In one such instance, the DNA demethylase Ten-Eleven-Translocation-2 (TET2) is implicated in altering the methylation status of various cancer–promoting, as well as tumor-suppressor genes. Our interest lies in interrogating whether TET-2 contributes to the alterations in the tumor suppressor gene Cx43’s expression and function and whether this signaling axis contributes to CRC development in an IBD model. To mirror the inflammatory environment of IBD, activated monocyte supernatants were added to HT-29 human colorectal adenocarcinoma cells. Furthermore, HT-29 cells were stably transfected to either overexpress or knock out Cx43 or TET2. These cells were then assayed to assess Cx43 and TET2 expression in a reciprocal fashion by looking at RNA expression, relative protein expression, and sub-cellular localization by immunofluorescence. The addition of activated monocyte supernatant resulted in an increase in the expression of Cx43. However, TET2 overexpression resulted in Cx43 downregulation, and, somewhat surprisingly, Cx43 overexpression resulted in a downregulation of TET2 expression. This seemingly paradoxical finding opened the possibility of a two-way interaction between TET2 and Cx43 rather than a unilateral effect of TET2 on Cx43 gene methylation. These findings indicate that there is a dynamic relationship between TET2 and Cx43 in the setting of inflammation and opens the doors to investigate how this relationship results in the progression from an inflammatory state to the development and progression of colorectal cancer
Crystal Clear Economics: Central Bank Transparency and Macroeconomics Stability
Get PDFThe issues facing global economic stability are influenced by central banks' transparency,
which has become increasingly important during modern monetary policy. Many studies,
policy conferences, and discussions about economic governance have focused on the
relationship between macroeconomic stability and central bank transparency. The basis
of this partnership is the idea that candid communication from central banking institutions
may influence expectations, build trust, and significantly improve the stability of the
economic environment.
Transparency in central banks has many different goals. First, it aims to make monetary
policy choices more predictable so that the public and market players can understand the
rationale behind central bank actions. This would reduce uncertainty in the financial
markets and the economy. Second, by encouraging transparent communication among
stakeholders, transparency helps to strengthen the central bank's reputation. Finally,
transparency is thought to be a strategy for enhancing the effectiveness of monetary
policy by influencing financial market expectations and behavior.
Moreover, transparency indices that measure the accessibility and clarity of central bank
communications are frequently developed as part of the evaluation of central bank
transparency. These indices are used by researchers and policymakers to assess and
compare the levels of transparency among various central banks, providing important
new perspectives on the potential effects of transparency on economic outcomes.
This study illuminates the Central Bank’s role in stabilizing the economy, minimizing
economic volatility, reducing exchange rate fluctuations, ensuring financial stability, and
managing inflation. Additionally, it underscores the practical importance of a
transparency index for central banks, specifically examining whether the level of
transparency influences critical indicators of macroeconomic performance
Shadi and Fadi
No full textA children's book, created by AUB students from the Education Department, for the course EDUC218 as a final project