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Entire Function with Two Separated Values
No full textIt’s known that an entire function with zeros and 1-points lying on a finite number
of rays must have finite order. This thesis considers a transcendental entire function
with two separated values in disjoint sectors. Given that such function is of finite
order, and under some conditions related to the sizes of the sectors, it’s possible to
determine the form of the function
Validation of the first Arabic version of the life skills scale among university students
Get PDFDespite the increasing recognition of positive life skills interventions to enhance the psychological and physical well=being of individuals, there is an absence of a valid and reliable Arabic measure of Life Skills (LS) amongst youth. This study aims at validating an Arabic Life Skills Scale (A-LSS) to assess the effectiveness of life skills interventions. A randomly selected sample of 1200 university students in Lebanon participated in this study. The exploratory-to-confirmatory factor analyses strategy was followed to examine the factor structure of the LSS. For that purpose, the sample was divided into two subsamples. The exploratory factor analysis results showed a nine-factor solution, with a strong reliability for the total scale (McDonald’s omega ω = 0.95) and all subscales (ω ranging from.68 to.91). The confirmatory analysis results showed excellent fit indices (CFI =.98, TLI = .97, GFI = .95; RMSEA = .031 [90% CI.028–.034] and SRMR = .061), after correlating residuals of items 53 and 54. Measurement invariance across genders was verified at the configural, scalar and metric levels. The A-LSS showed high reliability and validity of LS among Lebanese university students. This scale can be used as a valid tool to measure effectiveness of life skills health promotion interventions. © 2023 The Author(s). This open access article is distributed under a Creative Commons Attribution (CC-BY) 4.0 license
Multisystem inflammatory syndrome in children (MIS-C) and “Near MIS-C”: A continuum?
Get PDFIntroduction: Reports of multisystem inflammatory syndrome in children (MIS-C), following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, have been increasing worldwide, with an incidence varying significantly across studies based on the definition used for the diagnosis. At our tertiary medical center in Lebanon, we encountered several cases that presented a diagnostic challenge because they mimicked MIS-C but did not meet the US Centers for Disease Control and Prevention (CDC) definition. We decided to review these cases and describe their features in comparison with cases that met the CDC criteria of MIS-C and those that had an alternative diagnosis. Methods: This is a retrospective chart review of subjects aged <19 years old admitted to the American University of Beirut Medical Center (AUBMC) between March 1, 2020, and May 31, 2021, with suspected or confirmed MIS-C, following documented COVID-19 infection, with sufficient or insufficient criteria for diagnosis. Subjects were classified into 3 groups: “MIS-C”, “Near MIS-C” and “Alternative Diagnosis”. Results: A total number of 29 subjects were included in our cohort. Fever was present in all subjects. In the MIS-C group, evidence for cardiovascular system involvement was the most common feature followed by the mucocutaneous and gastrointestinal systems. In the “Near MIS-C” and “Alternative Diagnosis” group, gastrointestinal symptoms were the most common with only one patient with cardiac abnormalities and none with coagulopathy. Subjects with typical MIS-C presentation had higher inflammatory markers when compared to subjects in the other groups. Almost all the subjects had positive IgG for SARS-CoV-2. Of the 29 subjects, the Royal College of Paediatrics and Child Health (RCPCH) case definition would have identified all suspected cases without an alternative diagnosis as MIS-C, whereas the World Health Organization (WHO) and the CDC definitions would have excluded 6 and 10 subjects, respectively. Conclusion: MIS-C presents a diagnostic challenge due to the nonspecific symptoms, lack of pathognomonic findings, and potentially fatal complications. More research is needed to fully understand its pathogenesis, clinical presentation spectrum, and diagnostic criteria. Based on our experience, we favor the hypothesis that MIS-C has a continuum of severity that necessitates revisiting and unifying the current definitions. 2023 Khafaja, Youssef, El Zein, Boutros, Bou Karroum, Abdel-Halim, Salameh, Hodroj, El Meski, Nasrallah, Bidikian, Bou Saba, Arabi, Hanna-Wakim and Dbaibo
Novel SCN9A variant associated with congenital insensitivity to pain
Get PDFBackground: Congenital insensitivity to pain (CIP) is a rare autosomal recessive syndrome characterized by lack of pain perception and a wide spectrum of clinical signs such as anosmia and hyposmia. Variants in SCN9A gene are associated with CIP. We here report on a Lebanese family with three CIP patients referred for genetic investigations. Methods and results: Whole exome sequencing analysis revealed the presence of a novel nonsense, homozygous SCN9A pathogenic variant: SCN9A (NM_001365536.1): c.4633G > T, p.(Glu1545*) in exon 26. Conclusion: Our three Lebanese patients had CIP, urinary incontinence and normal olfactory function while two of them also presented with osteoporosis and osteoarthritis; this association of features has not been previously reported in the literature. We hope that this report would contribute to a better delineation of the phenotypic spectrum associated with SCN9A pathogenic variants. © 2023, The Author(s), under exclusive licence to Springer Nature B.V
Palestine in the Cloud: The Construction of a Digital Floating Homeland
Get PDFA widespread revolt during the months of April and May 2021 in the Palestinian city of Jerusalem, also known as Habbet Ayyar, responded to Israeli actions aiming to ethnically cleanse and force out residents from the neighborhood of Sheikh Jarrah in East Jerusalem, where approximately 3000 people reside, and to limit the movement and entry of Palestinians to Al-Aqsa Mosque. These measures were met with an unprecedented wave of youth-led protests against the Israeli army, police, security agencies, and settlers. Habbet Ayyar stands out not only for its innovative and effective use of new media to amplify the protests beyond Israel’s sphere of influence and control, but also for the unity displayed by fragmented Palestinians as they confronted Israel. By exploring the larger historical and geographical context of the movement that led to Habbet Ayyar, this article aims to understand how Palestinians have utilized, for the past 20 years, new media as a battleground—despite enforced digital colonialism—and how these media served to articulate and create what I call a digital “floating homeland”. The concept of a “floating homeland” is useful for exploring how the Palestinian virtual social movement has redefined and reconnected with Palestine beyond Israel’s control and fragmentation. This digital homeland is constructed through new technologies that have reshaped Palestinian self-identification and allowed for a virtual and digital reconceptualization of a borderless Palestine. © 2023 by the author
Cure Cycle In-process Monitoring of Advanced Composites via Reusable Flexible Ultrasonic Sensing Film
Get PDFEnvironmental and cost-saving advantages derived from the use of composites attract the aerospace and automotive industries as these materials offer significant structural and aerodynamic advantages over traditional metal structures. The composites industry, however, is concerned with the manufacturing processes as they cannot provide fast enough cycle time to match metal alloy processes. This research aims to develop a sensing technology in the form of a reusable in-situ cure monitoring and assessment system that can predict the formation of manufacturing defects and monitor the degree of cure.
First, a thin-film material is chosen from various PTFE-based material by prioritizing the debonding effect and signal transmission through the composite part. Then, the film is used to sandwich piezoelectric actuators and sensors to monitor out-of-autoclave carbon fiber composite plates using ultrasonic Lamb waves by temporarily adhering to the manufactured part creating an effective electromechanical coupling between the sensing film and the laminate. Initial results, through the analysis of the fundamental antisymmetric A0 mode at low frequencies, indicate that analyzing the velocity and amplitude of these waves over cure time determines minimum viscosity, gelation, and vitrification points. Experimental results also prove the feasibility of using such a reusable film for different post-curing cycles, always determining certain cure parameters.
Since some of the concerns this industry faces are the energy and time spent on long curing cycles to achieve permanent bonding between the matrix and fibers, the reusable PTFE thin sensing film is then used to monitor the same cure parameters for a shorter curing cycle than that suggested by the CFRP manufacturer. The results show that the determined three cure parameters are offset by the same time deducted from the cycle, highlighting the practicability of using such technology. To verify the viability of this approach, tensile testing and dynamic mechanical analysis (DMA) are performed on these composites. Tensile testing results show that the average tensile modulus for the shortened cycle is of similar values if not slightly higher than that of the normal cycle. DMA results verify both previous conclusions: time shift of cure parameters and enhanced mechanical and thermal properties of the shortened cycle.
With the help of DMA results, a computational model for the CFRP plate is developed to imitate the experimental in-process monitoring. The storage modulus for the used CFRP is extracted throughout the curing cycle and its trend is implemented into COMSOL combined structural and electrostatics multiphysics to simulate the same mechanical fluctuations of the CFRP during curing. Then, Lamb waves are excited and sensed via sandwiched piezoelectric transducers in a reusable PTFE sensing film to monitor the structural health of the structure. The three cure parameters are determined for both curing cycles, validating the efficiency of this numerical method. Also, while closely analyzing these computationally generated curves, an additional cure parameter defined as “gelation initiation” is proposed. Additionally, the decomposition of different wavefield modes is scrutinized to describe their scattering throughout the layered structure. A new entrapped antisymmetric mode appears inside the CFRP laminate at the start of the cure, which suggests that the previously studied A0 mode had been initially converted from the CFRP S0 mode.
Finally, the curing of adhesives used for structural bonding is monitored. By joining two fully cured CFRP plates with a prepreg epoxy film to be cured in the oven, the same previous methods are used to analyse the data extracted from the ultrasound monitoring of this adhesive. Additional S0A0 mode that is converted at the overlap is also analyzed. Then, post-cure monitoring on the CFRP plates is performed to remove the effect of heat and determine more accurate cure parameters. In the numerical model, sole A0 mode is actuated to enhance the scrutiny of mode conversion at the overlap. The numerical results, although heavily dependent on the adhesive film DMA curing results input, still highlight the desired cure points. Lastly, cocuring of both adhesive film and non-cured CFRP prepreg laminates is also tested experimentally where the A0 amplitude curve show more sensitivity towards the added epoxy cure parameters
The impact of AirSeal® on complications and pain management during robotic-assisted radical prostatectomy: a single-tertiary center study
Get PDFPurpose: We aimed to compare perioperative outcomes, post-operative complications, and opioid use between AirSeal® and non-AirSeal® robotic-assisted radical prostatectomy (RARP). Methods: We retrospectively collected data on 326 patients who underwent elective RARP at our institution either with or without AirSeal®. The first 60 cases were excluded accounting for the institutions’ learning curve of RARP. Patient demographics, oncologic, pathologic, and surgical characteristics between AirSeal® and non-AirSeal® cases were compared. Furthermore, outcomes of interest including operative time, length of stay, morbidity, and opioid use for pain management were compared between the two groups. Univariate linear and logistic regression models were developed. Results: The AirSeal® group consisted of 125 (38.3%) patients while the non-AirSeal® group consisted of 201 (61.7%) patients. No statistically significant difference was seen in terms of patient demographics, oncologic characteristics, surgical characteristics, and pathologic characteristics between the two groups. In addition, univariate linear regression showed that RARP with AirSeal® displayed shorter operative times by 12.3 min and a shorter length of hospital stay by 0.5 days compared to the non-AirSeal® group (p 2 complications (OR = 0.102) and a lower need for opioid use (OR = 0.49) compared to the non-AirSeal® group (p 2 complications, and lower odds of opioid use with respect to non-AirSeal® RARP. The efficacy and cost effectiveness of using the AirSeal® system during RARP should be further studied and evaluated by clinical trials. © 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature
Women in Protest Iconography across the SWANA Region
No full textThe mobilizations of the past thirteen years in Southwest Asia and North Africa suggest
a shift in the visual culture of the region. From the start of the Arab Spring in 2011 to the
latest uprising in Iran, the visual output of protests has been marked by the hypervisibility
of the figure of the female protester as an icon of revolution. The following thesis dissects
five cases of women in iconic protest imagery across the region: Egypt’s blue bra girl and
Turkey’s woman in red, Sudan’s Kandaka, Lebanon’s Kick-Queen, and Iran’s haircutting ceremonies. I both adopt and depart from Hariman and Lucaites (2007) study of
photojournalistic icons to explore different dimensions of iconicity and its impact on
women’s mobilization. From iconic images to iconic action, the newfound centrality of
women in protest imagery seems to be paving the way for new observations on visual
culture, gender dynamics, and communication in the region
What drives change in children receiving telephone-delivered Common Elements Treatment Approach (t-CETA)? A multiple n = 1 study with Syrian refugee children and adolescents in Lebanon
Get PDFBackground: Although the evidence-base for mental health and psychosocial support (MHPSS) interventions in humanitarian settings is growing rapidly, their mechanisms of change remain poorly understood despite the potential to improve the effectiveness and reach of interventions. Objective: This study aimed to explore the mechanisms or factors that drive change in a modular transdiagnostic telephone-delivered mental health intervention, Common Elements Treatment Approach (t-CETA). Participants and setting: Participants were Syrian refugee children and adolescents living in tented settlements in Lebanon. Methods: We used a multiple n = 1 design, drawing on secondary data from 9 children who completed t-CETA during a pilot randomized controlled trial. Results: Children with historical war-related trauma were more likely to show significant improvement across symptom clusters by the end of treatment compared to children presenting with depression related to daily living conditions. Children also showed fluctuating symptoms during the early stages of treatment (engagement and cognitive restructuring) but significant decline in symptoms after the trauma module (prolonged imaginal exposure) and depression module (behavioral activation). Salient external life events identified were starting or dropping out of school, working, change in living conditions, family conflict and the October Revolution; and interpersonal factors of parental engagement (with or without full attendance) and counsellor skills in building rapport were also identified as having an impact on treatment success. Conclusions: Implications of our findings are discussed in terms of integrating active ingredients into MHPSS programming, and building on parental and multi-sector involvement in child and adolescent mental health care in humanitarian settings. © 2023 Elsevier Lt
Solar-Regenerated Desiccant Belt for Direct Indoor Humidity Pumping Through Breathable Insulation Wall
No full textA humidity pump is proposed to extract latent load directly from the indoor space using a rotating desiccant-coated belt integrated in the building façade formed of an airgap and a breathable insulation. The system dries the airgap, creating the gradient needed to drive the indoor moisture outdoors. The belt is regenerated by direct exposure to solar radiation. The external side of the belt is equipped with variable shading mechanism for control of the regeneration temperature. A mathematical model was developed for the proposed system coupled with breathable insulation. The developed model was experimentally validated on a constructed prototype of the system and used to conduct a parametric study for an office space that generates typical latent load of 407 W. The study evaluated the system performance at different belt rotational speeds and shading percentages in three different climates: hot and humid, Mediterranean, and tropical climates.
Simulations were performed and optimal operating conditions of the belt were recommended at each hour of an occupancy period to maximize latent load removal. This was achieved by varying the belt rotational speed between 9.6 rph – 19.2 rph while maintaining a shading percentage of 40 %. As a result, the system was capable of extracting 110 W – 456 W of space latent load, which corresponded to 27 % - 112 % of the typical generated latent load of 407 W, while adding 32 W – 195 W of sensible load depending on the climate