American University of Science and Technology

Nasser A., Al Haj Hassan H., Abou Chaaya J., Mansour A., Yao K.

Spectrum Sensing (SS) plays an essential role in Cognitive Radio (CR) networks to diagnose the availability of frequency resources. In this paper, we aim to provide an in-depth survey on the most recent advances in SS for CR. We start by explaining the Half-Duplex and Full-Duplex paradigms, while focusing on the operating modes in the Full-Duplex. A thorough discussion of Full-Duplex operation modes from collision and throughput points of view is presented. Then, we discuss the use of learning techniques in enhancing the SS performance considering both local and cooperative sensing scenarios. In addition, recent SS applications for CR-based Internet of Things and Wireless Sensors Networks are presented. Furthermore, we survey the latest achievements in Spectrum Sensing as a Service, where the Internet of Things or the Wireless Sensor Networks may play an essential role in providing the CR network with the SS data. We also discuss the utilisation of CR for the 5th Generation and Beyond and its possible role in frequency allocation. With the advancement of telecommunication technologies, additional features should be ensured by SS such as the ability to explore different available channels and free space for transmission. As such, we highlight important future research axes and challenging points in SS for CR based on the current and emerging techniques in wireless communications.

Itani R., Tobaiqy M., Al Faraj A.

On the 30th of January 2020, the World Health Organization fired up the sirens against a fast spreading infectious disease caused by a newly discovered Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and gave this disease the name COVID-19. While there is currently no specific treatment for COVID-19, several off label drugs approved for other indications are being investigated in clinical trials across the globe. In the last decade, theranostic nanoparticles were reported as promising tool for efficiently and selectively deliver therapeutic moieties (i.e. drugs, vaccines, siRNA, peptide) to target sites of infection. In addition, they allow monitoring infectious sides and treatment responses using noninvasive imaging modalities. While intranasal delivery was proposed as the preferred administration route for therapeutic agents against viral pulmonary diseases, NP-based delivery systems offer numerous benefits to overcome challenges associated with mucosal administration, and ensure that these agents achieve a concentration that is many times higher than expected in the targeted sites of infection while limiting side effects on normal cells. In this article, we have shed light on the promising role of nanoparticles as effective carriers for therapeutics or immune modulators to help in fighting against COVID-19.

SALAMEH P., HAJJ A., BADRO D.A., ABOU SELWAN C., AOUN R., SACRE H.

• Mental health issues are frequently underestimated in developing countries, although they are expected to be highly prevalent, particularly in the context of a severe socio-economic crisis and political instability. • Fear of COVID-19 and fear of poverty were independently associated with higher stress and anxiety, while family satisfaction and financial wellness were linked to lower stress. • Combined fear of COVID-19 and financial distress were associated with further stress and anxiety. The COVID-19 pandemic has affected physical and mental health worldwide, particularly vulnerable populations with lower social and economic status. This study explored the independent and combined effects of the COVID-19 and economy-related variables on stress and anxiety among Lebanese adults in a developing country facing a severe socio-economic crisis and political turmoil. A cross-sectional study was conducted online between May 10 and 20, 2020, using the snowball sampling technique. All individuals over 18 were eligible. The final sample included 502 respondents. Higher stress and anxiety were associated with younger age, female gender, previous higher socio-economic status, having a family member with a chronic disease, fear of not getting access to treatment, fear of COVID-19, and physical violence at home. However, financial wellness and higher family satisfaction were significantly associated with lower stress. The multivariate analysis showed a significant interaction between fear of COVID-19 and financial wellness on estimated marginal means of stress and anxiety. The combined presence of fear of the pandemic and financial hardship is associated with higher stress and anxiety, particularly among women and younger Lebanese adults with difficult home circumstances. Thus, healthcare professionals need to screen for mental health problems among subgroups presenting multiple risk factors.

Itani R., Al Faraj A.

Despite major progress in both therapeutic and diagnostic techniques, lung cancer is still considered the leading cause of cancer mortality in the world due to the ineffectiveness of the classical treatments used nowadays. Luckily, the discovery of small interfering RNA (siRNA) planted hope in the hearts of scientists and patients worldwide as a new breakthrough in the world of oncology and a robust tool for finally curing cancer. However, the valuable siRNA must be protected and preserved to ensure the effectiveness of this gene therapy, thus nanoparticles are gaining more attention than previous years as the optimal carriers for this fragile molecule. siRNA-loaded nanoparticles are being extensively investigated to find the appropriate formulation, combination, and delivery route with one objective in mind—successfully overcoming all possible limitations shown in clinical studies and making full use of this novel technique to become the next generation treatment to wipe out many chronic diseases, including cancer. In this review, the benefits of using siRNA and nanoparticles in lung cancer treatment will be globally reviewed before discussing why and how nanoparticles and siRNA can be combined to achieve an efficient treatment of lung cancer for prospective clinical applications.

El Amine A., Chaiban J., Hassan H.A., Dini P., Nuaymi L., Achkar R.

The massive deployment of small cells in 5G networks represents an alternative to meet the ever increasing mobile data traffic and to provide very-high throughout by bringing the users closer to the Base Stations (BSs). This large increase in the number of network elements demands a significant increase in the energy consumption and carbon footprint followed by complex interference management. In order to address these challenges, we consider multi-level Sleep Mode (SM) where BS components with similar activation/deactivation times can be put to sleep. The deeper and higher energy efficient the SM is, the longer it will take the BS to activate, which might impose degradation in the Quality of Service (QoS). While this adds operational flexibility to the BS, it brings complex management to the operator. In this paper, we consider a heterogeneous network architecture where small cells can switch to different SM levels to save energy and reduce dropping rate. We propose a reinforcement learning algorithm for small cells that adapts their activities subject to service delay constraint. In this regard, the algorithm intelligently learns from the environment based on the co-channel interference, the cell buffer size and the expected cell throughput in order to decide the best SM policy. Numerical values show that important energy savings can be obtained with an acceptable dropping rate. Moreover, we show that while offloading users to the macro cell can significantly reduce their delay, dropping rate and the cluster energy consumption, it comes at a cost of decreasing the network energy efficiency up to 5 times compared with the case of no offload.

Megarbane A., Bizzari S., Deepthi A., Sabbagh S., Mansour H., Chouery E., Hmaimess G., Jabbour R., Mehawej C., Alame S., Hani A., Hasbini D., Ghanem I., Koussa S., Al-Ali M.T., et. al.

Background: Clinical and molecular data on the occurrence and frequency of inherited neuromuscular disorders (NMD) in the Lebanese population is scarce. Objective: This study aims to provide a retrospective overview of hereditary NMDs based on our clinical consultations in Lebanon. Methods: Clinical and molecular data of patients referred to a multi-disciplinary consultation for neuromuscular disorders over a 20-year period (1999–2019) was reviewed. Results: A total of 506 patients were diagnosed with 62 different disorders encompassing 10 classes of NMDs. 103 variants in 49 genes were identified. In this cohort, 81.4% of patients were diagnosed with motor neuron diseases and muscular dystrophies, with almost half of these described with spinal muscular atrophy (SMA) (40.3% of patients). We estimate a high SMA incidence of 1 in 7,500 births in Lebanon. Duchenne and Becker muscular dystrophy were the second most frequently diagnosed NMDs (17% of patients). These disorders were associated with the highest number of variants (39) identified in this study. A highly heterogeneous presentation of Limb Girdle Muscular Dystrophy and Charcot-Marie-Tooth disease was notably identified. The least common disorders (5.5% of patients) involved congenital, metabolic, and mitochondrial myopathies, congenital myasthenic syndromes, and myotonic dystrophies. A review of the literature for selected NMDs in Lebanon is provided. Conclusions: Our study indicates a high prevalence and underreporting of heterogeneous forms of NMDs in Lebanon- a major challenge with many novel NMD treatments in the pipeline. This report calls for a regional NMD patient registry.

Nasser A., Al Haj Hassan H., Mansour A., Yao K., Nuaymi L.

In Cognitive Radio (CR) networks, Primary User (PU) and Secondary User (SU) coexist to efficiently share the spectrum. PU has the right to access its dedicated channel at any time, while SU, operating in an opportunistic mode. can access only when PU is absent. Thus, SU should continuously monitor the channel to avoid any interference with PU when transmitting. Several factors, such as fading and shadowing adversely impact the PU SNR at the SU receiver making the Spectrum Sensing (SS) process more challenging. Recently, Intelligent Reflecting Surface (IRS) has been proposed to control the propagation channel for wireless systems. Introducing IRS in CR networks impacts the SS performance because of altering the channel. In this paper, we investigate the effect of deploying IRS on the SS by considering two scenarios: in (S1) the IRS is configured to enhance the PU signal at SU, while in the second scenario (S2), the IRS is configured to assist the Primary Receiver (PR). First, we highlight several important challenges and research directions. Then, we derive the analytical average detection probability for both (S1) and (S2). Results show that deploying IRS can significantly enhance SS even when the IRS is deployed to assist the PR.

Mallah N., Badro D.A., Figueiras A., Takkouche B.

Background Antibiotic resistance is a major public health concern. It has been associated with factors such as uncontrolled consumption, lack of knowledge, beliefs, and sociodemographic characteristics. Lebanon is characterized by high levels of antibiotic misuse, as almost half of the population self-medicates with antibiotics and over 30% of the antibiotics are dispensed without prescription. To-date, no studies determined adequately the association between knowledge, beliefs and antibiotic misuse in Lebanon. Objective To assess the association between level of knowledge and beliefs about antibiotics, and antibiotic misuse in Lebanon. Methods We conducted a cross-sectional study among 1,421 parents of schoolchildren using an anonymous self-administered Knowledge, Attitude and Practices questionnaire. The participants´ level of agreement with each item of knowledge and beliefs was measured using a Likert-type (0–10) scale. Misuse practices in the last month were detected through a series of questions aimed at determining the level of compliance with physicians´ instructions in terms of dosage and duration. Data were analyzed using logistic regression. Results 277 participants (16%) acknowledged using antibiotics in the previous month, 41% of whom showed at least one misuse behavior. Misconceptions and beliefs about antibiotics substantially increased the odds of their misuse. For instance, participants who believed that antibiotics were effective in treating viruses, cold, or sore throat infections were twice as likely to misuse antibiotics [Adjusted Interquartile Odds Ratio (aIqOR): 2.08 (95%CI: 1.32, 3.19), aIqOR: 1.81 (95%CI: 1.41, 2.29), aIqOR: 2.19 (95%CI: 1.61, 2.93), respectively]. Parents who usually keep antibiotics at home antibiotics for future use were more likely to misuse antibiotics [aIqOR: 2.44 (95%CI: 1.68, 3.46)]. Conclusions Our findings indicate that the low level of knowledge and the existence of erroneous beliefs about antibiotics are associated with increased odds of antibiotic misuse. Key elements including rationale prescription and control of dispensing should be addressed when designing educational campaigns against antibiotic misuse.

Chinnappan R., Al Faraj A., Abdel Rahman A.M., Abu-Salah K.M., Mouffouk F., Zourob M.

The surface protein overexpressed on cancer cells can be used as biomarkers for early detection of specific diseases. Anti-VCAM-1 and anti-IL4Rα DNA aptamers specific to VCAM-1 and IL4Rα receptors that are overexpressed in 4T1 tumor-bearing mice could be used as potential biomarker for both diagnostic and therapeutic applications in cancer biology. Cell Viability and luciferase assay of 4T1-Luc2 cancer cells in the presence of anti-VCAM-1 ssDNA or anti-IL4Rα RNA aptamers was assessed by monitoring the changes in the absorbance and the fluorescence of Alamar blue dye. The aptamer-conjugated SPIO magnetic beads, used for the selective targeting to tumor sites, were monitored using noninvasive MRI and Bioluminescence imaging (BLI). Cell viability and luciferase assays showed that both anti-VCAM-1 and anti-IL4Rα aptamers favor the depletion of cancer cells and limit tumor progression. Microscopic analyses confirmed that the target specific aptamers significantly trigger tumor cell apoptosis and limit cancer cell growth in vitro. The intravenous injection of SPIO nanoparticle-conjugated aptamers were further confirmed using noninvasive MRI and Bioluminescence imaging. Anti-VCAM1 and anti-IL4Rα aptamers, specific to VCAM-1 and IL4Rα receptors overexpressed in 4T1-Luc2 tumor-bearing mice, were used as diagnostic and therapeutic tools.

Raad G., Bakos H.W., Bazzi M., Mourad Y., Fakih F., Shayya S., Mchantaf L., Fakih C.

Suboptimal human semen handling in vitro may induce sperm damage. However, the effects of semen swim-up, pellet swim-up, density gradient, and density gradient followed by SU on sperm motility, morphology, DNA fragmentation, acrosome reaction, intracellular reactive oxygen species, and mitochondrial activity were not fully understood.To study the impact of four sperm preparation techniques on sperm functional parameters.This study was conducted on 60 infertile men with a minimum sperm concentration of 20 × 106 /ml and total sperm motility of ≥30%. Each raw semen sample was divided into four aliquots. Each aliquot was prepared by one of the tested techniques. Various sperm characteristics were assessed before and after sperm preparation.Density gradient and density gradient followed by SU resulted in significantly higher DNA fragmentation percentages compared with semen swim-up (p < 0.001 and p < 0.001, respectively) and pellet swim-up (p < 0.001 and p < 0.001, respectively). Significantly higher percentages of spermatozoa with intact acrosome were detected in semen swim-up (p < 0.001) and pellet swim-up (p < 0.001) compared with raw semen. The percentage of reactive oxygen species-positive spermatozoa was significantly higher after pellet swim-up (p < 0.001), density gradient (p < 0.001), and density gradient followed by SU (p < 0.001) than raw semen. In addition, the percentages of 100% stained midpiece (active mitochondria) were significantly higher in semen swim-up (p < 0.001) and pellet swim-up (p < 0.001) compared with raw semen.To the best of our knowledge, this is the first report comparing the impact of these techniques on various sperm functional parameters. Semen swim-up was more effective than density gradient in selecting better spermatozoa in terms of DNA integrity, reactive oxygen species levels, acrosome status, and mitochondrial activity. Randomized clinical trials comparing these four techniques are required to test their impact on embryo development and pregnancy outcomes.