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Seismic Hazard Assessment of the Lebanese Restraining Bend: A Neo-deterministic Approach
No full textThe Lebanese Restraining Bend is an active bend along the Dead Sea Transform Fault in the eastern Mediterranean region where several destructive earthquakes have occurred throughout history. In this paper, we assess the gross features of the seismic hazard of the Lebanese Restraining Bend by applying a neo-deterministic method that involves the generation of synthetic seismograms distributed on a regular grid over the study area. We use the regional seismicity, seismic source zones, focal mechanism solutions, and velocity structural models. We present maps of ground displacement, velocity, and acceleration. This is the first study that generates neo-deterministic seismic hazard maps for the Lebanese Restraining Bend using representative ground motion modeling. Our results show that displacement values of 15–30 cm and velocity values of 30–60 cm/s can be expected along most of Lebanon. In addition, 0.15–0.30 g acceleration values can dominate most of the Lebanese territory and surrounding areas. It is evident from these results that the study area in general and Lebanon in particular constitute a high seismic hazard area, which necessitates further attention from the authorities regarding the precaution measures needed to mitigate the effects of potential catastrophic seismic events; in addition, more detailed investigations are needed at local scale for specific sites of interest. © 2023, The Author(s), under exclusive licence to Springer Nature Switzerland AG
Regularity Theorem For Gaussian Spaces
No full textAn analogue of the regularity theorem for Schwartz distributions is proven in the case the coupling between the space and its dual is done via the Gaussian measure. The result is then studied in infinite dimensions and a counterexample is obtained for the case when the space of test functions is an inductive limit of finite-dimensional ones
Growth Differentiation Factor-15 (GDF-15) and Inflammation in Diabetic Kidney Disease: A Friend, A Foe, Or A Fellow Traveler.
No full textIntroduction: Diabetes Mellitus is associated with several complications, among which is diabetic kidney disease (DKD). DKD is considered the strongest predictor of mortality in diabetic patients and the main cause of kidney failure worldwide. It has been shown that tissue injury, inflammation, and stress conditions in DKD are closely correlated with the circulating levels of transforming growth factor-β (TGF- β) related cytokine, also known as Growth Differentiation factor-15 (GDF-15). GDF-15 being a stress-responsive cytokine has been implicated in a variety of physiological and pathological processes. Recent studies have suggested that GDF-15 may play a role in the pathogenesis of DKD by modulating inflammatory responses in the kidney. A newly introduced monoclonal antibody; AV-380, has been developed to target GDF-15. It acts by specifically binding circulating GDF-15, blocking its interaction with its receptor and subsequent downstream signaling pathways. Collectively, this lead us to study the inflammatory role of GDF-15 in DKD.
Methods: C57BL/6J male black mice were allocated into 2 groups: a control group and a HFD+STZ induced type II diabetic group. These groups were further divided into 3 subgroups: group treated with saline, group treated with 7.5 mg/kg of AV-380, and a group treated with 20 mg/kg of AV380. Treatment lasted for a duration of 8 weeks. Functional, histopathological, biochemical and molecular studies were performed on kidney tissues from all groups.
Results: Our results show that treatment with AV-380 significantly attenuated renal injury by inhibiting hyperglycemia-induced oxidative stress. AV-380 treatment ameliorates kidney injury and this was transduced functionally by a reduction in proteinuria. At the histological level, PAS and MT staining revealed reduced glomerulosclerosis and collagen deposition respectively. In addition, looking at the general inflammatory markers, we noticed a significant decrease in mRNA expression of IL-6, IL-23, IL-12, IL-1β and TNF-α upon treatment with AV-380 irrespective of dose. This suggests that GDF-15 may have a regulatory effect on the inflammatory status in DKD. To further delineate the mechanism by which AV-380 is regulating inflammation, we will be assessing a set of anti-inflammatory cytokines, as well as specific cell markers of immune cells namely macrophages and neutrophils.
Conclusion: Our findings indicate a crosstalk between GDF-15 and inflammation in diabetes-induced renal injury. Pharmacological interventions aimed at manipulation of the GDF-15 signaling cascade in future studies may be beneficial in a clinical setting of diabetes-induced renal complications
Exploring the relationship between gratitude and depression among older adults with chronic low back pain: a sequential mediation analysis
Get PDFIntroduction: Gratitude has been identified as a key factor in a number of positive health-related outcomes; however, the mechanisms whereby gratitude is associated with well-being among older adults with chronic pain are poorly understood. Using the Positive Psychological Well-Being Model as a theoretical framework, the objective of the present study was to examine the serial mediating effects of social support, stress, sleep, and tumor necrosis factor-alpha (TNF-α) on the relationship between gratitude and depressive symptoms. Methods: A total sample of 60 community-dwelling older adults with chronic low back pain (cLBP) provided blood samples for high-sensitivity TNF-α and completed the Gratitude Questionnaire, Perceived Stress Scale, and the PROMIS Emotional Support, Sleep Disturbance, and Depression forms. Descriptive statistics, correlation analyses, and serial mediation analyses were performed. Results: Gratitude was negatively associated with perceived stress, sleep disturbance, and depression, and was positively associated with social support. No significant association was observed between gratitude and TNF-α. After controlling for age and marital status, analyses revealed that perceived stress and sleep disturbance sequentially mediated the association between gratitude and depressive symptoms. Conclusion: Perceived stress and sleep disturbance may be potential mechanistic pathways by which gratitude impacts negative well-being. Targeting gratitude as a protective resource may be a potential therapeutic tool to improve psychological and behavioral outcomes in older adults with cLBP. 2023 Makhoul and Bartley
Pharmacogenomics in practice: a review and implementation guide
Get PDFConsiderable efforts have been exerted to implement Pharmacogenomics (PGx), the study of interindividual variations in DNA sequence related to drug response, into routine clinical practice. In this article, we first briefly describe PGx and its role in improving treatment outcomes. We then propose an approach to initiate clinical PGx in the hospital setting. One should first evaluate the available PGx evidence, review the most relevant drugs, and narrow down to the most actionable drug-gene pairs and related variant alleles. This is done based on data curated and evaluated by experts such as the pharmacogenomics knowledge implementation (PharmGKB) and the Clinical Pharmacogenetics Implementation Consortium (CPIC), as well as drug regulatory authorities such as the US Food and Drug Administration (FDA) and European Medicinal Agency (EMA). The next step is to differentiate reactive point of care from preemptive testing and decide on the genotyping strategy being a candidate or panel testing, each of which has its pros and cons, then work out the best way to interpret and report PGx test results with the option of integration into electronic health records and clinical decision support systems. After test authorization or testing requirements by the government or drug regulators, putting the plan into action involves several stakeholders, with the hospital leadership supporting the process and communicating with payers, the pharmacy and therapeutics committee leading the process in collaboration with the hospital laboratory and information technology department, and healthcare providers (HCPs) ordering the test, understanding the results, making the appropriate therapeutic decisions, and explaining them to the patient. We conclude by recommending some strategies to further advance the implementation of PGx in practice, such as the need to educate HCPs and patients, and to push for more tests’ reimbursement. We also guide the reader to available PGx resources and examples of PGx implementation programs and initiatives. Copyright © 2023 Kabbani, Akika, Wahid, Daly, Cascorbi and Zgheib
Long-term Stable Dye Sensitized Solar Cells: Aqueous and Organic Based Electrolyte Systems
No full textIn order to meet the current and future energy needs, adoption of alternative renewable energy sources is of great importance, in addition to taking over fossil fuels due to the latter’s limited supply and adverse impacts on the environment. Nowadays, dye-sensitized solar cells (DSSCs), one of many solar technologies, hold out a promising technique to harvest solar energy and convert it to electrical energy. This is due to its simplicity of manufacturing, low cost, flexibility, relatively high conversion efficiency and minimal environmental toxicity. The Grätzel group originally presented the DSSC in 1991, and since then, many research groups have made significant progress in this area. Recent reports show that DSSCs have the potential to perform very efficiently under low light conditions, which is an attracting feature for indoor applications. However, conventional DSSCs contain organic solvents that are known for their toxicity and solvent volatility that shorten the lifetime of a DSSC. As a result, the adoption of new electrolyte systems with low volatility, low toxicity while maintaining long-term stability is a promising avenue to pursue. On the eco-friendliness side, the use of water-based gelled systems is very appealing since it would lessen the toxicity effects and volatility of the electrolyte solvent. The use of Ionic liquids (ILs) is also a good approach to be employed for the latter case mentioned above. Hence, we propose to study two different types of copper-based electrolyte systems; one is in a gelled water medium and another with low-volatility organic solvent incorporating ionic liquids. Both electrolyte systems will be investigated in fully functional DSSCs under low light conditions and for a prolonged period of time
SGLT2 Inhibitor—Dapagliflozin Attenuates Diabetes-Induced Renal Injury by Regulating Inflammation through a CYP4A/20-HETE Signaling Mechanism
No full textDiabetic kidney disease (DKD) is a serious complication of diabetes, affecting millions of people worldwide. Inflammation and oxidative stress are key contributors to the development and progression of DKD, making them potential targets for therapeutic interventions. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have emerged as a promising class of drugs, with evidence demonstrating that they can improve renal outcomes in people with diabetes. However, the exact mechanism by which SGLT2i exert their renoprotective effects is not yet fully understood. This study demonstrates that dapagliflozin treatment attenuates renal injury observed in type 2 diabetic mice. This is evidenced by the reduction in renal hypertrophy and proteinuria. Furthermore, dapagliflozin decreases tubulointerstitial fibrosis and glomerulosclerosis by mitigating the generation of reactive oxygen species and inflammation, which are activated through the production of CYP4A-induced 20-HETE. Our findings provide insights onto a novel mechanistic pathway by which SGLT2i exerts their renoprotective effects. Overall, and to our knowledge, the study provides critical insights into the pathophysiology of DKD and represents an important step towards improving outcomes for people with this devastating condition. © 2023 by the authors
Structural behavior of beams cast using normal and high strength concrete containing blends of ceramic waste powder and blast furnace slag
No full textIn general, the use of ceramic waste powder (CWP) in concrete production is limited to few percentages (i.e., less than approximately 10–15% of Portland cement), given the resulting decrease in concrete strength and durability. This paper seeks to assess the relevance of blending CWP with blast furnace slag (BFS) to foster pozzolanic reactions and reinstate the drop in strength and structural performance of reinforced concrete (RC) members. Two categories of normal- and high-strength concrete (NSC and HSC) mixtures possessing 34 and 71 MPa compressive strengths are tested in this program. The RC beams measured 2-m in length and were differently configured by steel reinforcements to assess the flexural and shear strengths as well as the bond to embedded spliced rebars. Regardless of the steel configuration, results showed that the structural properties curtail when the concrete mixtures are prepared with 10% CWP replacement rate. This was attributed to a dilution effect and higher CWP porosity that detrimentally alter the concrete microstructure and strengths. The drop in flexural, shear, and bond strengths was found to be fully restored with the use of ternary binder composed of 55% cement, 35% BFS, and 10% CWP. Such results are in line with the improved concrete strength and durability, revealing the relevance of blending CWP with BFS to foster synergistic effects and reinstate the structural properties of NSC and HSC beams. Findings of this work can increase the CWP added-value for the construction industry, while reducing the cement carbon footprint. © 2023 The Author(s
Prevalence of negative mental health status during COVID-19 pandemic among general population of seven Arab countries: A cross-sectional study of 28843 participants
No full textBackground: Previous studies documented a narrow scope of knowledge about the negative mental health status during the lockdown following the COVID-19 pandemic, especially in Arab countries. Aim: We aimed to assess the association between negative mental health status and the COVID-19 pandemic and determine the different factors affecting mental health among the general population of seven Arab countries. Methods: This study is a multinational cross-sectional questionnaire-based survey conducted online from June 11, 2020 to June 25, 2020. The depression, anxiety, and stress Scale 21 Items (DASS-21) and the Event scale-Revised Arabic version (IES-R-13) scales were used. Multiple linear regressions were performed to study the association between the scales' total scores with COVID-19 and demographic characteristics. Results: A total of 28,843 participants from seven Arab countries were included. During the COVID-19 pandemic, the prevalence of mental health disorders has significantly increased. A total of 19006 participants (66%) were affected by variable degrees of depression, 13,688 (47%) had anxiety, and 14,374 (50%) had stress ranging from mild to severe. Higher levels were associated with other factors, such as lower age, female gender, chronic disease, unemployed, fear of getting infected, and a history of psychiatric disorders. Conclusion: Our study findings show an increased incidence of mental disorders during the pandemic. This is expected to play a crucial role in guiding a psychological support strategy provided by healthcare systems to the general public during pandemics. © 2023 Indian Journal of Psychiatry
Factors motivating lebanese youth to adopt COVID-19 good practices: a cross-sectional study
No full textBackground: It is now widely acknowledged that young people can be asymptomatic carriers of the COVID-19 virus. While vaccines are successful, COVID-19 good practices continue to be useful in controlling the virus transmission. This study aimed to investigate the associated risk factors impacting the youths' adoption of COVID-19 good practices in Lebanon. Methods: Data were collected through an online survey. The analyzed sample included 602 young people. Results: Our results indicate that around half the youth sample in our study adhere to COVID-19 good practices. COVID-19 good practices are more likely to be adopted by individuals who are more worried about their health and those who live with their partners. Furthermore, media trust was a significant predictor of COVID-19 good practices. Conclusion: Media can play a larger role in promoting good practices through youth-targeted programs. By identifying community influencers and encouraging peer-to-peer communication, it is possible to engage youth who distrust the media and persuade them to adopt COVID-19 good practices. Copyright © 2023 Bou-Hamad and Hoteit