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Unraveling the Crosstalk between Lipids and NADPH Oxidases in Diabetic Kidney Disease
Get PDFDiabetic kidney disease (DKD) is a serious complication of diabetes mellitus and a leading cause of end-stage renal disease. Abnormal lipid metabolism and intrarenal accumulation of lipids have been shown to be strongly correlated with the development and progression of diabetic kidney disease (DKD). Cholesterol, phospholipids, triglycerides, fatty acids, and sphingolipids are among the lipids that are altered in DKD, and their renal accumulation has been linked to the pathogenesis of the disease. In addition, NADPH oxidase-induced production of reactive oxygen species (ROS) plays a critical role in the development of DKD. Several types of lipids have been found to be tightly linked to NADPH oxidase-induced ROS production. This review aims to explore the interplay between lipids and NADPH oxidases in order to provide new insights into the pathogenesis of DKD and identify more effective targeted therapies for the disease. © 2023 by the authors
Noncontact nondestructive ultrasonic techniques for manufacturing defects monitoring in composites: a review
Get PDFComposite materials are widely used in most industries due to their high specific strength, specific stiffness, and their relatively lighter weight compared to other traditional materials. However, the presence of defects arising from manufacturing processes or during service loads can make these structures more susceptible to a diminished performance. Furthermore, the former defects are inevitable in composite structures, but they can be reduced. Each type of defect requires specific inspection techniques and configurations. In this work, a review of the different types of composites manufacturing processes and their corresponding resultant defects is presented with the various nondestructive evaluation techniques employed for these defects’ characterization. The emphasis of this paper is on ultrasonic inspection and detection techniques for they present high sensitivity to surface/subsurface discontinuities, superior depth of ultrasonic penetration for flaw detection, feasibility on large scales, and instantaneous and detailed images production. Notably, noncontact ultrasonic testing techniques are also reviewed, air-coupled techniques in specific, and highlighted as a fine alternative to conventional contact inspection systems as they reduce the restrictions that coexist with the use of couplants. Moreover, these ultrasonic testing techniques are summarized to show the latest research progress achieved in the field of air-coupled ultrasonic inspection systems for manufacturing defects’ monitoring in composite structures including delamination, porosity, dryness, waviness, and resin lack/excess. Finally, we highlight the type and central frequency of the transducers and experimental results present in literature and obtained in terms of both detection and size of the defects. © The Author(s) 2023
Effects of Deliberate Instruction in Metacognitive Reading Strategies on the EFL Learners’ Comprehension of Various Text Types Across Proficiency Levels
No full textThe existing empirical studies on the effects of deliberate metacognitive reading interventions on students’ comprehension remain inconclusive. Also, previous studies have barely focused on both the literal and the high-order levels of comprehension with a scarcity in research that investigates the effects of metacognitive strategy instruction on learners’ comprehension across text types and proficiency levels. As there is paucity of empirical research and due to the controversy in the literature, the researcher conducts this exploratory study that aims to (a) examine the association between learners’ use of support, global, and problem-solving metacognitive reading strategies, and their literal and higher-order reading comprehension globally and as the text type changes; (b) investigate the impact of deliberate instruction in metacognitive strategies in improving the learners’ use of metacognitive reading strategies; (c) investigate the effect of deliberate instruction in metacognitive reading strategies in improving the literal and higher-order reading comprehension of students globally and as the text type changes; (d) determine if the deliberate instruction’s effect on the reading comprehension of students is more pronounced in high proficient students compared to those with lower proficiency; and (e) determine if metacognitive reading strategies mediate the relationship between deliberate instruction and literal and higher-order reading comprehension. The study follows a quantitative quasi-experimental research design. The participants were seventh grade EFL learners in a private school in Greater Beirut Area. Data were collected using the Test of English as a Foreign Language-Junior Level (TOEFL), the Survey of Reading Strategy Questionnaire (SORS), and 8 reading comprehension tests that measured learners’ literal and higher-order comprehension in narrative, descriptive, persuasive, and expository texts. Students were divided randomly into control and experimental groups, where the experimental group was taught using the Optimal Learning Model (OLM) whereas the control group was taught in a regular implicit pattern that focused on teacher questioning and sharing. Correlational analyses indicated a significant relationship between overall, global, problem-solving, and support metacognitive reading strategies and literal and higher-order comprehension on the general level and across the four text types. ANCOVA analyses showed that the OLM intervention has a significant impact on the students’ use of overall, global, problem-solving, and support metacognitive reading strategies. Factorial ANCOVA (FANCOVA) proved that the OLM intervention has a statistically significant effect on the learners’ post-literal and post-higher-order reading comprehension globally. However, these results change when the text type and the level of comprehension change. Lastly, Hayes Process Macro Model 4 showed that the OLM intervention has a significant indirect effect on both the literal and higher-order reading comprehension through metacognitive reading strategies, which means that metacognitive reading strategies mediate the relationship between OLM intervention and literal and higher-order reading comprehension of students. The study’s findings prove that the use of metacognitive language learning strategies helps learners develop their reading strategies and performance and increase their reading comprehension achievement. It also proved that metacognitive strategy instruction and training sessions have a positive effect on improving the participants' use of metacognitive reading strategies, which implies that students recognize the benefits of employing them in EFL reading and find metacognitive strategies helpful in approaching reading materials. However, the effect of using metacognitive reading strategies changes based on the comprehension level (literal or higher order), text types, and proficiency levels of students. This is due to different reasons that are explored in the body of the research. Lastly, the fact that metacognitive reading strategies mediate the relationship between the metacognitive reading instruction and reading comprehension of students highlights the importance of reconceptualizing reading teaching and improving reading comprehension outcomes through metacognitive reading strategies. Results were discussed in light of the limitations of the study and pedagogical implications and recommendations for future research were made
Experts Involved in Claims and Disputes Resolution: Mapping and Classification of Engagement Possibilities
Get PDFThe resolution of claims and disputes requires the typical involvement of professionals belonging to the various entities participating in the project construction process, including owners, contract engineers, project managers, contractors, and subcontractors. Depending on the availability of expertise within such organizations, it is common to see the engagement of outside experts being sought to help throughout the phases of claims and disputes evolution. The objective of this research is to highlight the roles played by such experts and map these roles along the internationally recognized standard claim and dispute administration timeline by the International Federation of Consulting Engineers (FIDIC). The followed methodology included (1) reviewing the relevant literature and case law on the subject, (2) highlighting the possible spectrum of expert roles while being informed by those numerous roles played by the first author on several project cases over three decades, (3) mapping the encountered expert roles onto a standard claim and dispute resolution timeline through conceptualizing the possible engagement scenarios in each of the concerned phases, and (4) synthesizing the classes of such played expert roles. The findings revealed a spectrum of roles that can be asked of experts by way of providing guidance, advice, substantiation, facts assertion, testimony, and/or assessment. The work outcome is of importance both to construction professionals who seek the appointments of experts and to those who act as experts in the resolution of construction claims and disputes. © 2023 American Society of Civil Engineers
Validity and Reliability of the Arabic Version of the Patient Health Questionnaire-9 (PHQ-9) in Patients with Heart Failure (HF) in Lebanon
Get PDFBackground: Depression has been recognized as a common comorbidity in heart failure (HF). The significant presence of depression has been associated with increased mortality among patients with HF (Fan et al., 2014). Depression screening is now recommended by the European Society of Cardiology and the Italian Geriatric Cardiology Society's HF guidelines. The use of self-reported screening tools for patients is a major method of examining for depression. The Patient Health Questionnaire-9 (PHQ-9) is one of the most commonly used and approved self-reporting questionnaires for screening patients for depression. The PHQ-9 has been clinically validated in the HF population, making it an increasingly relevant clinical and research tool. The PHQ-9 was translated to Arabic and used to screen for depression in a Saudi community sample and in Lebanese cardiac patients. However, no research validating the properties of the Arabic PHQ-9 in cardiac patients has been reported in Lebanon.
Study aim: The overall aim of this study was to examine the psychometric properties and cultural validity of an Arabic version of the PHQ-9 as a depression screening tool in HF patients in Lebanon.
Design: This is a secondary data analysis. The study used interview data collected in two studies. The first study used an observational cross-sectional design to evaluate the psychometric properties of the Minnesota Living with Heart Failure questionnaire in Lebanese patients with HF. The second study used a correlational descriptive design to describe self-care behaviors and their determinants in a sample of Lebanese patients with HF.
Sample: The current study sample included a total of 208 patients who were included in the two studies described above.
Procedure: IRB approval was secured. The two data sets were then de-identified and merged. Statistical analysis included the calculation of the Cronbach’s alpha coefficient. Two experts in cardiology and one patient were asked to evaluate the cultural appropriateness of the Arabic version of the PHQ-9 in the Lebanese population and its relevance to depression by rating each item on a 4-point scale, and an index was calculated for each item of the PHQ-9 and the overall scale. We also compared patients with different New York Heart Association (NYHA) classes on their PHQ-9 scores using an ANOVA test to test the hypothesis that patients with a higher NYHA class will have higher depression scores. Furthermore, the Pearson correlation coefficient was used to evaluate the association between the PHQ-2 (a short version of the PHQ-9) and PHQ-9 scores. Since socioeconomic status and educational attainment have been linked to depression, ANOVA was used to compare PHQ-9 means across different groups of education and income, in addition to the t-test to compare PHQ-9 means by gender and comorbidity status.
Results: Out of the 208 patients, 37 (17.78%) were positively screened for depression by PHQ-9 at a cutoff ≥ 10. The psychometric assessment of the PHQ-9 showed acceptable internal consistency (Cronbach’s alpha = 0.823). Two experts and a HF patient evaluated the Arabic version of the PHQ-9 in the Lebanese population to be culturally appropriate, overall. The Exploratory Factor Analysis yielded two factors: psychosomatic and cognitive. Furthermore, there were significant differences in PHQ-9 categories by NYHA class. The questionnaire was found to be reliable and valid, with potential for minor adjustments for cultural appropriateness.
Conclusion: These results can inform the implementation of depression screening in HF clinics in Lebanon, with advanced practice nurses using the Arabic PHQ-9 to assess patients, refer them to psychiatry when needed, and monitor their response to treatment over time
Three-dimensional modeling of a tethered UAV–buoy system with relative-positioning and directional surge velocity control
Get PDFThis work presents the nonlinear dynamical model and motion controller of a system consisting of an unmanned aerial vehicle (UAV) that is tethered to a floating buoy in the three-dimensional (3D) space. Detailed models of the UAV, buoy, and the coupled tethered system dynamics are presented in a marine environment that includes surface water currents and oscillating gravity waves, in addition to wind gusts. This work extends the previously modeled planar (vertical) motion of this novel robotic system to allow its free motion in all three dimensions. Furthermore, a directional surge velocity control system (DSVCS) is proposed to allow both the free movement of the UAV around the buoy when the cable is slack, and the manipulation of the buoy’s surge velocity when the cable is taut. Using a spherical coordinates system centered at the buoy, the control system commands the UAV to apply forces on the buoy at specific azimuth and elevation angles via the tether, which yields a more appropriate realization of the control problem as compared to the Cartesian coordinates, where the traditional x-, y-, and z-coordinates do not intuitively describe the tether’s tension and orientation. The proposed robotic system and controller offer a new method of interaction and collaboration between UAVs and marine systems from a locomotion perspective, and offers a low-cost and low-logistics alternative to crewed vessels for marine missions. It has potential applications in search-and-rescue missions, monitoring and sensing operations, and floating objects manipulation and retrieval. The system is validated in a virtual high-fidelity simulation environment, which was specifically developed for this work, while considering various settings, operating conditions, and wave scenarios. © 2022, The Author(s), under exclusive licence to Springer Nature B.V
The impact of COVID-19 on the mental health of Lebanese pharmacists: A national cross-sectional study
Get PDFIntroduction: The COVID-19 pandemic has induced a global mental health crisis with variable consequences. This study aimed to assess the psychological impact of COVID-19 regarding anxiety, insomnia, depression, and response to trauma on pharmacists in Lebanon during COVID-19, and to identify factors contributing to psychological distress. Methods: This was a cross-sectional study among pharmacists that involved the use of the 7-item Generalized Anxiety Disorder (GAD-7), 7-item Insomnia Severity Index (ISI), Patient Health Questionnaire 9-item depression module (PHQ-9), and Impact of Event Scale revised (IES-R) subscales. Descriptive statistical analyses were performed to determine the study distribution. The associations between the scores and the participants’ characteristics were assessed using the Chi-square test. Four binary logistic regression models were used to evaluate the association between the scores and the potential confounders, followed by four multivariable logistic regressions. An alpha of 0.05 was used to determine statistical significance. Results: Participants comprised 311 pharmacists from all Lebanese districts, of whom 251 (80.7%) were females and 181 (58.2%) aged between 26 and 35 years. The majority of the participants were community pharmacists (n = 178, 57.2%). A considerable proportion of participants had symptoms of anxiety (n = 128, 41.2%), insomnia (n = 64, 20.6%), depression (n = 157, 50.5%), and subjective stress (n = 227, 78.8%). Higher anxiety (aOR: 1.73, 95% CI: 1.08; 2.78, p-value: 0.02), higher depression (aOR: 3.06, 95% CI: 1.73; 5.39, p-value: 0.001), and higher stress (aOR: 1.86, 95 percent CI: 1.11; 3.14, p-value: 0.02) scores were significantly associated with pharmacists who reported that their work involves contact with infected/suspected COVID-19 patients. Interestingly, pharmacists who expressed concern about contracting COVID-19 infection had significantly higher anxiety (aOR: 2.35, 95% CI: 1.40; 3.94, p-value: 0.001) and higher depression scores (aOR: 2.64, 95% CI: 1.49; 4.67, p-value: 0.001) respectively. Conclusion: The preliminary results from pharmacists in Lebanon reflect increase in stress, burden, and frustration felt by pharmacists, creating a negative impact on their mental health and well-being during the global pandemic. As frontline healthcare workers, the role of pharmacists in the community should not be overlooked, and their mental health should be well investigated. Copyright © 2023 Safwan, Hammoudi Halat, Akel, Younes, Rahal, Mourad, Akiki, Cherfane, Saade, Bouraad, Dabbous and Sakr
The management of hepatocellular carcinoma. Current expert opinion and recommendations derived from the 24th ESMO/World Congress on Gastrointestinal Cancer, Barcelona, 2022
Get PDFThis article summarises expert discussion on the management of patients with hepatocellular carcinoma (HCC), which took place during the 24th World Gastrointestinal Cancer Congress (WGICC) in Barcelona, July 2022. A multidisciplinary approach is mandatory to ensure an optimal diagnosis and staging of HCC, planning of curative and therapeutic options, including surgical, embolisation, ablative strategies, or systemic therapy. Furthermore, in many patients with HCC, underlying liver cirrhosis represents a challenge and influences the therapeutic options. © 2023 The Author(s
The Urban Recovery of Affordable Housing in Post-Blast Karantina (Beirut)
No full textAfter the August 4, 2020 explosion devastated the Karantina area adjacent to the port, throngs of volunteers and NGOs poured in to help with relief efforts, including reconstruction of damaged housing stock. With the absence of significant involvement from the state, long-term urban recovery has proven elusive. This experience is in keeping with previous reconstruction cycles that Beirut has lived through, as in the case of post-Civil War redevelopment and in the aftermath of the July 2006 war. In these earlier cases, the state delegated its role to non-state actors and became a facilitator of activity instead. This trend has also been apparent in the post-disaster reconstruction of Karantina. As a consequence, housing stock has been affected by declining affordability and accessibility, rising rental prices, increased levels of vacancy, and continued lack of facilities and services. To confront these problems, this thesis argues that urban recovery should supersede reconstruction. In this study, urban recovery is conceived as an open-ended “holistic and multi-layered process,” one that moves past “physical and the humanitarian” interventions and instead proposes an inclusive approach that is “locally informed and socially anchored” (Al-Harithy, 2021).
This thesis approaches urban recovery through the lens of housing and begins by documenting historic housing conditions and developments to identify pre-disaster advantages and disadvantages. Historical explorations suggest that Karantina has always been a place of refuge and affordable housing in the city of all those who seek it. Moving on to post-disaster experience, the thesis identifies several threats. These may be described as follows. The disruptive actions by landlords after the port blast, such as evictions, rent hikes, and the conversion of residential units into commercial spaces, are a result of a post-disaster reality, absence of a coherent social and urban policy by the authorities as well as the ongoing economic crisis. Therefore, there is a threat of losing the social diversity and the housing affordability in Karantina that has always hosted diverse low-income groups who sought living and working in proximity to the city center. Tension between different nationalities, as well as different sectarian groups, threatens the diversity of Karantina’s housing occupancy. Additionally, there is a threat of large scale development and gentrification, which might affect the scale of low income housing stock, especially since Karantina was not protected under the building freeze imposed after the blast. Finally, the thesis makes several planning recommendations at both the neighborhood and city scale that will lead towards the urban recovery of affordable housing in post-blast Karantina
LESCA: LightwEight Stream Cipher Algorithm for emerging systems
No full textRecently, there has been a dire need for lightweight cryptographic solutions, which exhibit low computational complexity and require few resources. In this paper, we present LESCA, a novel dynamic key-dependent lightweight stream cipher, which consists of two main functions, a typical round function based on cryptographic primitives, and a function that updates these primitives. The update is performed in a selective (partial) manner while encrypting a block, and in full after each δ blocks/iterations. As such, LESCA consumes minimal resources and introduces a very low latency. The originality of this solution stems from the fact that the cryptographic primitives get updated even when encrypting the same message. Several performance and security tests were performed to confirm that the proposed cipher is robust and efficient, especially for limited devices and real-time applications. The proposed cipher achieves a high throughput; for example, when implemented on a Raspberry Pi (RPI4) device, LESCA provides an enhancement of at least 343% when compared to the Advanced Encryption Standard (AES), 72% over a recent one-round cipher scheme, and 43% improvement compared to a recent LORCA stream cipher that outperforms the Simon and Speck algorithms. © 2022 Elsevier B.V