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Characterizing the Effect of Knocking Down SLC35B4 Orthologs in Drosophila melanogaster
No full textSLC35B4 is a transmembrane solute carrier responsible for transporting nucleotide sugars, UDP-Xylose and UDP-N-acetylglucosamine, to the endoplasmic reticulum and/or Golgi apparatus. It provides the substrate for glycosyltransferases, allowing the glycosylation of glycoproteins, glycolipids, proteoglycans, glycosaminoglycans and regulating several biological processes. It has been shown to be implicated in chronic diseases such as diabetes, schizophrenia, and various types of malignancies, including glioma, hepatic, colorectal, prostate and gastric cancer. Although it was shown to have a critical role in neuroprotection against injuries and diseases by providing astrocyte-glial communication through maintaining healthy mitochondrial transfer, it has not been well studied in terms of brain function and behavior. Given the crucial urge to understand its function in an invertebrate model to later extrapolate to mammalian models, adding to that the ease of genetic manipulation and assessment provided by a variety of tools, Drosophila melanogaster is shown to be an attractive model to use when studying brain structure and function. One of the transporter’s ortholog, Efr - transporting UDP-N- acetylglucosamine, GDP-fucose and UDP-xylose - is partially involved in glycosaminoglycan synthesis and in regulating NOTCH signaling through O- fucosylation when knocked down in wing discs. It was shown that null mutations of glycosylation enzymes affect neuronal function, life span, sleep, behavior, and brain development, such as GlcNAcylation enzymes. Yet, the effect of this sugar transporter and its homolog has not been studied, being the substrate source of such glycosylation processes. In this study, we aimed to characterize the effect of knocking down (Efr-KD, CG14511-KD) on flies’ behavior, brain, and to assess the potential implications on the transporters’ functionality. Additionally, we also sought to gain indirect insights into the potential substrates that CG14511 might be transporting. Our findings revealed that knocking down SLC35B4 orthologs disrupts the flies’ behavior, with CG14511-KD additionally displaying brain enlargement. Furthermore, our preliminary data suggested the involvement of this protein in transporting UDP-N-acetylglucosamine and a potential role in NOTCH signaling. Molecularly, we suggested that SLC35B4 orthologs might interact with Hippo and TOR pathway possibly by Yorkie; Moreover, we proposed that the prolonged and better-quality life that is mainly shown in upon Efr-KD is also linked to TOR pathway. Therefore, this highlights the role of these orthologs in cancer promotion and anti-aging processes
On the Linear and Nonlinear Dynamics of the Hasegawa-Mima Equation
Full text linkUnderstanding turbulence in plasmas is essential for studying transport properties
in magnetically confined fusion devices. This thesis studies the Hasegawa-Mima
(HM) model, which describes the evolution of electrostatic potential fluctuations
in a plasma. First, we derive the HM model from first principles using fundamental
conservation equations.
Analytical studies of the HM model are then performed to investigate the role
of the linear term and its effect on the system dynamics. In particular, this study
explores the evolution of an initial electrostatic potential perturbation initialized as
white noise. The effect of the linear term on the dynamics is highlighted through
its dependence on the density gradient. The steepness of the density profile is
varied, therefore, assessing the impact of the linear term on the overall dynamics.
Then, numerical simulations of the HM model are conducted using FreeFEM++.
The simulation results are then analyzed in light of the analytical results. The re
sults show that an increase in the amplitude of the electrostatic potential occurs
in the gradient region, and there is no spreading of the turbulence beyond that
regio
Antioxidant Properties of Functionalized Tomato Sauce and Leather
No full textAs global concern about health, sustainability and food security grow, valorizing food byproducts has become an essential strategy in functional food development. In this context, this study aimed to develop and evaluate functional tomato-based product (tomato leather and tomato sauce) by incorporating tomato byproducts with key mediterranean ingredients such as olive powder, pea protein and aromatic herbs.
The tomato byproducts were processed into powdered form and incorporated into new formulations of tomato leather and sauce. In this study, Soxhlet extraction was used to measure total phenolic content (TPC) and antioxidant activity assessments were conducted using the Folin-Ciocalteu (F-C) method and ABTS essay.
Accelerated shelf-life analysis (high temperature- high humidity) over 12 weeks evaluated changes in antioxidant potential, color, pH, water activity, and microbial safety of the newly formulated tomato products. Statistical analysis assessed differences and antioxidant potential and product stability.
Results showed that tomato seeds had the highest TPC (91.43 mg GAE/100 g), while the skin exhibited better antioxidant potential (31.45 μmol TE/g). The tomato leather, enriched with olive powder and spices, had higher TPC (210.1 mg GAE/100 g) and antioxidant activity (41.02 μmol TE/g) compared to the tomato sauce enriched with olive powder and tomato peel powder (142.79 mg GAE/100 g; 23.85 μmol TE/g). A strong correlation (Pearson's coefficient R = 0.953) between TPC and antioxidant potential was observed.
Over 12 weeks, tomato leather maintained stable water activity and microbial load, though its pH decreased. Its antioxidant potential showed an overall increase, linked to color darkening due to Maillard reactions. Tomato sauce showed fluctuations in water activity and a slight decrease in pH, with antioxidant potential increased over time, correlated with color changes.
The study demonstrates the potential of using tomato byproducts and Mediterranean ingredients to enhance both sustainability and nutritional value
Perceptions of Ancillary Botanic Gardens by Institutional Green Space Owners in Lebanon
No full textThis study explores the perception of institutional green space owners and managers in
Lebanon regarding the implementation of Ancillary Botanic Gardens (ABGs). ABGs
represent a novel approach to botanical gardens, offering opportunities for conservation,
education, and community engagement. Despite their potential benefits, the extent to
which this concept is accepted remains unclear. Through qualitative in-depth interviews
with institutional green space owners across academic, commercial, cultural, and tourism
sectors, this research examines their perceptions, motivations, capabilities, and the
opportunities and challenges associated with transforming the institutional spaces into
ABGs. By investigating the perception on ABG implementation, this study contributes to
a deeper understanding of when and how these gardens can be effectively established in
Lebanon
A Gaussian Measure on Periodic Distributions
No full textWe study a construction of producing measures on a compactification of a space of periodic distributions, with the aim of producing a measure on the uncompactified space. We demonstrate that starting from an expression motivated from physics, we get a measure supported on a space of periodic distributions
ER Stress-Induced Modifications of the mRNA Levels of Specific Tight Junctions, Calcium Signaling Molecules, and Transporters in Caco-2 and HCT-116 Colorectal Cancer Cell Lines
Full text linkIntroduction: Colorectal cancer (CRC) and inflammatory bowel disease (IBD) share pathophysiological features that contribute to their progression, mainly through chronic inflammation. In addition, endoplasmic reticulum (ER) stress, which dysregulates calcium homeostasis, was linked to the progression of CRC and IBD by altering the expression of calcium signaling molecules and junctional proteins. Furthermore, CRC and IBD were shown to modify the expression of specific cationic and anionic transporters (OCTN1,2 and OAT2). OCTN1 and OCTN2 are shown to have anti-inflammatory roles through their specific substrates, acetylcholine, and carnitine, respectively, whereas OAT2 plays a crucial role in transporting anti-cancerous drugs, especially 5-Fluorouracil. Preliminary work in the lab has shown that thapsigargin (TG), a potent ER stress inducer, significantly modulates the protein expression of different proteins involved in cellular integrity, such as Zo-1, Ecad, Cx-43 and in proteins involved in calcium homeostasis, essential for the proper functioning of the ER. However, little information is known about the mechanism of TG-induced ER stress, on the mRNA levels of crucial mediators involved in cell integrity, calcium homeostasis (Pmca1&4, TRPV6, NCX1, Orai-1, Stim 1&2, Serca2&3, RYR1&3, ITRP2&3), and drug uptake (OCTN1,2 and OAT2).
Aim: This study investigates the mechanisms of TG-induced ER stress in two CRC cell lines, Caco-2 and HCT-116, by evaluating 1) the cell cycle profile of two cell lines in response to TG and 2) the mRNA levels of essential mediators involved in maintaining calcium signaling homeostasis and junctional proteins involved in maintaining cellular integrity, and drug uptake. Methods: Two colorectal cancer cell lines (Caco-2 and HCT-116) were used throughout the study. MTT assay and trypan blue assay were used, respectively, to determine the effect of TG concentrations on the metabolic activity and viability of the cells. After selecting the suitable concentration of TG (1 μM), HCT-116 and Caco-2 cell lines were cultured and exposed to 1 μM TG for 4, 8, and 24 hours to induce ER stress. Propidium iodide assay was used to detect variations in the cell cycle profiles of Caco-2 and HCT-116 in untreated and TG-treated cells at different time points. Finally, real-time PCR analysis assessed the mRNA expression levels of ER stress markers (Bip and Chop), OCTN1,2, OAT2, calcium signaling proteins (Pmca1&4, TRPV6, NCX1, Orai-1, Stim 1&2, Serca2&3, RYR1&3, ITRP2&3), and junctional proteins (Zo-1, Ecad, Cx-43). Results: This study showed that 1 μM TG, a concentration known to induce ER stress by blocking SERCA, is suitable for studying TG effects in HCT-116 and Caco-2. TG at 1μM induced cell cycle arrest in both cell lines. Furthermore, PCR analysis indicated differential regulation of key calcium signaling pathways, junctional proteins, and OCTN1, OCTN2, and OAT2, suggesting complex cellular responses to ER stress. Specifically, the stress marker Bip showed a sustained increase at all time points. However, Chop increased at 4 and 24 hours after a significant decrease after 8 hours of treatment. Junctional proteins showed substantial increases after 24 hours of treatment. Channels responsible for calcium efflux (NCX-1, PMCA1&4) showed significant increases after 24 hours of treatment. TRPV-6, a channel responsible for calcium entry, also showed a significant increase after 24 hours. Serca 2&3, RYR 1&3, and ITRP 2&3, channels responsible for calcium transport in the ER, showed substantial increases after 24 hours. Orai-1 and STIM 1&2, elements of the store-operated calcium entry (SOCE) system, also showed significant increases after 24 hours. Finally, OCTNs and OAT2 also showed substantial increases after 24 hours. Conclusion: This study reveals a significant link between ER stress and the dysregulation of calcium signaling and transport mechanisms in two CRC cells. The sustained increase in Bip, a marker of ER stress, indicates that prolonged ER stress critically influences cellular responses in CRC. Notable fluctuations in Chop expression, alongside increases in junctional proteins and calcium transport channels after 24 hours, highlight the complex adaptive processes to ER stress. The upregulation of calcium channels (TRPV-6, NCX-1, PMCA1&4) and SOCE components (Orai-1, STIM 1&2) suggests a compensatory mechanism to restore calcium homeostasis, which is vital for cell proliferation, apoptosis, and survival-key factors in CRC progression. Additionally, the increased expression of OCTN 1/2 and OAT2 may shift cellular transport dynamics, affecting drug metabolism and resistance. However, it is worth noting that previous work in the lab showed ER stress did not affect the protein expression of OCTN2 and OAT2. This finding, along with the increase in the mRNA expression of OCTN2 and OAT2, indicates that the increase in the mRNA levels was not reflected in the protein expression. This exciting observation highlights the importance of further investigating the factors that hindered the expression of these transporters. Overall, these findings advance our understanding of the mechanisms connecting ER stress to signaling pathway dysregulation in CRC. Future research into these pathways, especially in the context of (IBD) and its association with CRC, could further provide new avenues for CRC treatment
Enhancing Power Quality and Energy Trading in Distribution Network Enabled with Blockchain
Full text linkThis thesis aims to develop a methodology for optimizing energy flow in a distributed network characterized by a distributed system operator (DSO), energy management gateway (EMG), renewable energy (RE) sources and grid. The users of different buses will play a major role in optimizing the power flow, in addition to supplying the needed demand. Based on the location and size of renewables and stored energy, it is expected to reach the least power losses, cost, and voltage deviations possible in the network. The network is supported by blockchain to ensure secure and transparent transactions in addition to facilitating trading between peers. The network is subjected to time domain power flow (TDPF), Prophet forecast, and peer-to-peer (P2P) trading connected to a blockchain to reach optimal configuration
A Road Traffic Queueing Model Balancing Emissions and Cost
Full text linkThis paper examines a highway system using a queueing theory model, with parameters estimated from realistic data. Preliminary results include estimation of key performance indicators such as throughput, mean number of vehicles, and emissions. The model
identifies the optimal number of lanes and speed limit that minimizes the combined costs
of road construction and traffic delays. Additionally, the study extends to include a second
objective, which is minimizing carbon emissions. Our results, comparing the results of
both objectives, demonstrate that emissions considerations can influence the design of
highway systems, and lead to significantly higher costs. In order to explore the trade-offs
between reducing costs and emissions, we analyze this resulting two-objective
optimization through the characterization of Pareto-optimal (efficient) solutions and their
application to realistic scenarios. We observe that significant cost saving can be achieved
(e.g. 20%) if one allows a small increase in emissions (e.g. by 0.5%) over the level
stipulated by the single-objective emission minimization model
The Intellectual History and Reception of Bahāʾ al-Dīn al-ʿĀmilī’s Tashrīḥ al Aflāk (d. 1621)
No full textThis thesis explores the intellectual contributions of Bahāʾ al-Dīn al-ʿĀmilī (1547–1621), a 16th-century polymath, Shaykh al-Islām, and prominent scholar active under Shah ʿAbbās I in Safavid Iran. Renowned for his expertise acrosss multiple disciplines, al-ʿĀmilī played a pivotal role in shaping the Safavid intellectual landscape, particularly in the mathematical sciences. His works reflect both an engagement with earlier scholarly traditions and an effort to refine and adapt knowledge to the evolving educational and institutional framework of Safavid madrasahs.
Among his many contributions, Tashrīḥ al-Aflāk (Anatomy of the Celestial Spheres) stands out as a concise yet influential treatise on Islamic theoretical astronomy (ʿilm al-hayʾa). Originally designed as an introductory text for Safavid students, Tashrīḥ al-Aflāk also engaged a more advanced scholarly audience through al-ʿĀmilī’s own gloss/self-commentary (Ḥāshiya), which refined its pedagogical presentation while situating it within the broader tradition of ‘ilm al-hay’a. This dual function—both as a teaching text and a site for scholarly debate—highlights al-ʿĀmilī’s role in the transmission and development of mathematical sciences.
I argue that al-ʿĀmilī’s gloss demonstrates an active engagement with astronomy, building on the traditions of the Maragha and Samarqand schools. His work reflects the broader intellectual culture in which astronomy, philosophy, and theology were deeply interconnected. By addressing theological concerns within an astronomical framework, al-ʿĀmilī underscores the interwoven nature of the rational sciences in the post-classical Islamic world. Through a close reading of his explanatory comments, rhetorical strategies, and pedagogical techniques, I demonstrate how Tashrīḥ al-Aflāk functioned both as a sophisticated scholarly work and an instructional guide. This dual role is most evident in the comprehensive commentary Qānūn al-Idrāk fī Tashrīḥ al-Aflāk (The Law of Perception in the Anatomy of the Celestial Spheres) by the lesser-known yet highly significant student of al-ʿĀmilī: Muḥammad Kāẓim Tunikābūnī (d. after 1623–4).
The influence of Tashrīḥ al-Aflāk extended beyond Safavid Iran, shaping intellectual discourses in Mughal India, where it was widely studied and commented upon by scholars. By tracing the transmission, adaptation, and commentary tradition surrounding Tashrīḥ al-Aflāk, this thesis contributes to a broader understanding of Safavid-era scholarship’s enduring impact on the Islamic world.
The Friendship Forest: The Power of Kindness
No full text“The Friendship Forest: The Power of Kindness” is a heartwarming children’s story that explores the importance of empathy, standing up against bullying, and the transformative power of kindness. Through the journey of Riri the raccoon and his forest friends, the narrative gently introduces young readers to concepts of exclusion, courage, and friendship. As characters learn to speak up and support one another, the story reinforces moral values and encourages positive social behavior. Vibrantly illustrated and thoughtfully written, the book aims to inspire children to create inclusive and caring communitie