185 results on '"Abdallah SA"'
Search Results
2. Efficacy and safety of ciprofol versus propofol for induction of general anaesthesia or sedation: A systematic review and meta-analysis of randomised controlled trials
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Abdallah Saeed, Mariam Elewidi, Ahmad Nawlo, Amr Elzahaby, Asmaa Khaled, Abdalla Othman, Mohamed Abuelazm, and Basel Abdelazeem
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ciprofol ,general anaesthesia ,meta-analysis ,pain ,propofol ,sedation ,systematic review ,Anesthesiology ,RD78.3-87.3 - Abstract
Background and Aims: Propofol has been used in medical practice as an anaesthetic drug for producing and sustaining general anaesthesia due to its advantages. However, it also has drawbacks, including injection-related discomfort. Recently, ciprofol has emerged as a promising anaesthetic drug that may overcome many drawbacks associated with propofol. In this systematic review and meta-analysis, we assess the efficacy and safety of ciprofol compared to propofol in different anaesthesia procedures. Methods: The study protocol was registered in the International Prospective Register of Systematic Reviews (ID: CRD42023458170). Central, PubMed, EMBASE, Scopus and WOS were searched for English literature until 26 February 2024. Meta-analysis was performed using RevMan. The risk of bias was assessed using the RoB 2.0 tool. Results were reported as risk ratios (RRs), mean differences (MDs) and 95% confidence intervals (CIs). Results: Nineteen randomised controlled trials were included in our analysis, with 2841 participants. There was no difference between ciprofol and propofol in the success rate of endoscopy (RR: 1.01, 95% CI: 0.99, 1.02; P = 0.44), while ciprofol showed a significant increase in the success rate of general anaesthesia/sedation (RR: 1.01, 95% CI: 1.00, 1.02; P = 0.04). Ciprofol showed significantly lower pain on injection (RR: 0.14, 95% CI: 0.09, 0.22; P < 0.001), lower adverse events (RR: 0.80, 95% CI: 0.69, 0.92; P = 0.002) and higher patient satisfaction (standardised mean difference (SMD): 0.36, 95% CI: 0.24, 0.48; P < 0.001). Conclusion: Ciprofol exhibited a comparable efficacy to propofol in inducing general anaesthesia and sedation with fewer adverse events, less pain on injection and higher patient satisfaction. These collective findings may suggest that ciprofol can be used as an alternative drug to ensure effective general anaesthesia/sedation induction in the future.
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- 2024
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3. The impact of childhood abuse on patients with obsessive–compulsive disorder: an Egyptian study
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Yasser Abo Raya, Mohammad Gamal Sehlo, Reehab Saeed Mahdy, Heba Mesbah Kotb, and Abdallah Saad Ibrahim
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Obsessive–compulsive disorder ,Childhood abuse ,Psychiatry ,RC435-571 - Abstract
Abstract Background The presence of childhood abuse is expected to have a great impact on several psychological domains on obsessive–compulsive disorder (OCD) patients. This study was designed to assess the psychological impact of history childhood abuse (emotional abuse, physical abuse, sexual abuse, and emotional and physical neglect) on five psychological domains among OCD patients (self-esteem, depression, suicidal risk, cognitive functions, and anxiety). Methods This cross-sectional study included 101 OCD patients who were seen in the psychiatric department’s outpatient clinic at Zagazig University Hospital. They were diagnosed according to DSM-IV (SCID-I interview). All the patients were assessed using Childhood Trauma Questionnaire (CTQ-28), the Hamilton Depression Rating Scale (HDRS), Hamilton Anxiety Rating Scale (HAM-A), Beck’s Suicide Scale, Rosenberg Self-Esteem Scale, and the MoCA scale (Montreal Cognitive Assessment Test). Results The prevalence of childhood abuse in the studied group was 74.3%. 24.8% with emotional abuse, 20.8% with physical abuse, 16.8% with sexual abuse, and 11.9% of patients with emotional and physical neglect. The different types of childhood abuse (emotional, physical, and sexual abuse) were significantly associated with decreased self-esteem and increased depressive symptoms, while emotional and physical neglect were associated with decreased self-esteem only among OCD patients. The most powerful and significant predictor of lower self-esteem and depression was sexual abuse, and it was also the only significant predictor of increased suicidal risk among OCD patients. Conclusions History of childhood abuse was significantly associated with decreased self-esteem and increased depressive symptoms among OCD patients. Only history of sexual abuse was significantly associated with increased suicidal risk. So, evaluation of the childhood abuse history is highly important among OCD patients to be incorporated in the management plan to reduce the suffering of OCD patients and for better improvement.
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- 2024
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4. The efficacy and safety of difelikefalin for pruritus in hemodialysis patients: a systematic review and meta-analysis of randomized controlled trials
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Abdallah Saeed, Iman Abdelhady Elshnoudy, Yehya Khlidj, Radwa Radwan, Mariam Kamal, Mahmoud Hamdi, Abdullah Alsaid, Mustafa Turkmani, and Mohamed Abuelazm
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Difelikefalin ,pruritus ,hemodialysis ,systematic review ,meta-analysis ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Background Chronic kidney disease–associated pruritus (CKD-ap) is a common complication that negatively affects the quality of life. Difelikefalin has emerged as a novel FDA-approved drug to manage CKD-ap. This systematic review and meta-analysis will assess the efficacy and safety of Difelikefalin versus placebo to manage CKD-ap.Methods PubMed, Scopus, WOS, Central, and Embase were systematically searched until November 2023. RevMan was used to perform meta-analysis. Quality assessment was conducted using the Cochrane RoB 2.0 tool. Results were reported as risk ratio (RR) and mean difference (MD) with a 95% confidence interval (CI). PROSPERO ID: (CRD42023485979).Results Five RCTs with a total of 896 participants were included. Difelikefalin significantly decreased the weekly mean WI-NRS score (MD: −0.99 [−1.22, −0.75], p ˂ .00001), 5-D itch scale total score (MD: −1.51 [−2.26, −0.76], p > .0001), and Skindex-10 total score (MD: −7.39 [−12.51, −2.28], p = .005), but showed significantly higher adverse events (RR: 1.26 [1.03, 1.55], p = .03), versus placebo. However, there was no significant difference between both groups in serious adverse events (RR: 1.42 [0.78, 2.57], p = .25) or death (RR: 0.81 [0.19, 3.34], p = .77).Conclusion Difelikefalin appears to be a promising agent for the management of CKD-induced pruritus in patients with end-stage renal disease. However, evidence is still underpowered due to the paucity of the current data; therefore, more robust RCTs are required to confirm the benefit of Difelikefalin.
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- 2024
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5. Parameters Influencing Regression Rate of Solid Rocket Fuels
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Ceo, Ubiquity Interface Incorporated, Usa, Abdallah Sa, and Osemwengie O
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Nuclear engineering ,Environmental science ,Regression rate ,Solid-fuel rocket - Published
- 2019
6. Attachment Patterns and their Relationship with Relationship Crisis Management during the Engagement Period in Jordan
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Khawla Mahmoud Al-Arman and Abdallah Salem Al-Mahaireh
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Attachment patterns ,relationship crisis management between partners ,engagement period ,Education - Abstract
Objectives: This study aimed to explore the relationship between attachment patterns and the management of relationship crisis between partners during the engagement period in Jordan. Methods: The study employed a descriptive correlational approach. Two scales were used: the Attachment Patterns Scale and the Relationship Crisis Management Scale. The study sample consisted of a convenient sample of 412 engaged individuals in Jordan. Results: The results revealed that the most prevalent attachment pattern among engaged individuals during the engagement period was the secure attachment pattern, with a percentage of 92.7%. The avoidant attachment pattern followed at a percentage of 3.9%, while the least common pattern was the anxious attachment pattern at 3.4%. Furthermore, the results also showed a high level of relationship crisis management among engaged individuals during the engagement period. A positive linear relationship was found between secure attachment style and relationship crisis management, while an inverse relationship was observed between anxious and avoidant attachment patterns and relationship crisis management between partners. Conclusions: The results underscore the importance of considering attachment patterns and relationship crisis management during the engagement period in Jordan and reflect the need for developing educational and therapeutic plans to comprehend attachment patterns and their role in influencing crisis management processes, to arrive at effective solutions for facing and managing crises.
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- 2024
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7. Assessment of Hounsfield Units and Factors Associated with Fragmentation of Renal Stones by Extracorporeal Shock Wave Lithotripsy: A Computerized Tomography Study
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Abdallah Saud Alharbi, Moawia Gameraddin, Awadia Gareeballah, Zahra Jibril Shrwani, Moa’ath Abdullah Sindi, Hassan Ibrahim Alsaedi, Abdulaziz A. Qurashi, Khalid M. Aloufi, Abdullah Fahad A. Alshamrani, and Amel F. Alzain
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fragmentation ,CT number ,renal stones ,ESWL ,serum calcium ,uric acid ,Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
The success rate of extracorporeal shock wave lithotripsy (ESWL) is influenced by various factors, including stone density, and is determined through computed tomography scans in terms of Hounsfield units (HU). Materials and Methods: This retrospective single-center study was conducted in the King Fahad Hospital. Sixty-seven adult patients with renal and ureteric stones were selected randomly and enrolled in the study. Their ages ranged from 20 to 69 years. The patients were examined with non-contrast enhancement (NCCT) to assess the HU of their stones and were consequently treated with ESWL. Results: Of the 67 patients, 37.3% had stones that were completely fragmented, while 62.7% had stones that were partially fragmented. The HU, location of the stone, multiplicity of the stone, and patient age were found to be significant factors contributing to stone fragility (p-values < 0.05). The HU data were found to have a positive significant linear correlation with serum calcium (r = 0.28, p-value = 0.036), while serum acid had a negative correlation (r = −0.55, p-value < 0.001). Thus, the probability of calcium-containing stone formation increases with increased HU. In contrast, uric acid stone formation likely develops with decreasing HU with serum uric acid. Renal stones in patients with diabetes mellitus and hypertension were not completely fragmented compared to those without clinical history. Conclusions: Mean HU, location of the stone, laterality, stone status, and the number of ESWL sessions are the most significant factors affecting stone fragility. CT attenuation values can predict the composition of stones from serum calcium and uric acid examinations. Hypertension and diabetes mellitus are risk factors for renal stone fragmentation.
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- 2024
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8. Parameters Influencing Regression Rate of Solid Rocket Fuels
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Osemwengie O, Abdallah SA, Morgan HP, and Fanegan JO
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Burn Rate Modification ,Hybrid Rocket Engines ,UAV ,Solid Rocket Motors ,Propellant Additives - Abstract
This review paper provides a compilation of works from 1966 to 2018 pertaining to the study of altering the burn rate for solid fuel rockets. This paper serves to catalog the current state of research on burn rate altering additives and other common methods for tailoring the burn rate of solid rocket fuels for specific applications. Solid rocket motors (SRM) and hybrid rocket engines (HRE) both utilize solid fuels, while SRMs use a solid oxidizer mixed into the fuel and HREs use liquid or gas oxidizer separated from the fuel. There are many different methods for controlling the burn rate of these motors and engines, such as: fuel and oxidizer choice and concentration, additives, grain configuration, and combustion chamber pressure. The methods for controlling burn rate for each particular rocket type are discussed in their own sections, however most additives that mix with the solid fuel remain the same across the SRMs and HREs with the exception of those that behave as oxidizers. The main goal of this study of the modification, not just increasing, of the burn rate for these fuels is their use in long distance unmanned aerial vehicle (UAV) applications. HREs have many benefits that make them ideal for UAVs, including: low cost, added safety and ease of storage, and low burn rate. HRE have the added benefit of increased safety due to the physical separation of the fuel and oxidizer, and any additives that release oxygen during decomposition would not be ideal. Additives are a key element discussed in this paper, as the concentration can be varied to precisely tailor the burn rate of a mixture. The additives alter the burn rate by influencing the activation energy, heat of reaction, and efficiency of energy feedback.
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- 2019
9. Prestressed CFRP Plates and Tendon Strengthening of Steel–Concrete Composite Beams
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Lamies Elgholmy, Hani Salim, Alaa Elsisi, Abdallah Salama, Hesham Shaaban, and Ahmed Elbelbisi
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composite beams ,strengthened ,advanced material ,prestressed plate ,tendons ,3D FEM ,Technology ,Science - Abstract
This study aims to enhance the ultimate capacity and stiffness of steel–concrete composite beams through external strengthening with prestressed carbon fiber-reinforced polymer (CFRP) plates and post-tensioned CFRP tendons. A 3D finite element model was developed using ANSYS and validated using experiments. The impact of various parameters on the capacity of the beam was investigated, including the level of post-tensioning in the CFRP tendons, tendon profile, degree of shear connection, and beam load level when adding strengthening CFRP tendons. Results indicate that reinforcing composite beams with bonded CFRP plates using post-tensioning tendons with trapezoidal and parabolic profiles can increase maximum load capacity by 37% and 60%, respectively, while maintaining high stiffness. This study also indicates that the optimal strengthening conditions for the composite beam are when the beam is loaded up to 70% of its capacity and has a composite action degree of 100%.
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- 2024
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10. Catatonia after COVID-19 infection: scoping review
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Abdallah Samr Dawood, Ayia Dawood, and Samr Dawood
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Catatonia ,akinetic mutism ,COVID-19 ,SARS-CoV-2 ,delirium ,Psychiatry ,RC435-571 - Abstract
Aims and method Catatonia has been increasingly described in cases of COVID-19; we therefore aimed to investigate the evidence for catatonia in patients with COVID-19. We searched PubMed, EMBASE, PsycINFO, BIN and CINAHL databases for articles published in English, from the initial descriptions of the COVID-19 pandemic to January 2022. Results A total 204 studies were identified, 27 (13%) of which met the inclusion criteria. The evidence available was based on case reports. The articles included in this review identified a total of 42 patients, ranging from the ages of 12 to ≥70 years, with confirmed or possible catatonia during or after a COVID-19 infection. Clinical implications This review provides valuable information to clinicians in medical practice for treating patients with COVID-19, and a foundation for further research for this uncommon syndrome of COVID-19.
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- 2023
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11. Early fusion outcome after surgical treatment of single-level and multi-level pyogenic spondylodiscitis: experience at a level 1 center for spinal surgery—a single center cohort study
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Motaz Hamed, Simon Brandecker, Tim Lampmann, Harun Asoglu, Abdallah Salemdawod, Erdem Güresir, Hartmut Vatter, and Mohammed Banat
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Urgent spinal surgery ,Spinal instrumentation ,Pyogenic spondylodiscitis ,Single-level ,Multi-level ,Intervertebral fusion and instrumentation ,Orthopedic surgery ,RD701-811 ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
Abstract Study design Retrospective single center cohort study. Purpose Spinal instrumentation in combination with antibiotic therapy is a treatment option for acute or chronic pyogenic spondylodiscitis (PSD). This study compares the early fusion outcome for multi-level and single-level PSD after urgent surgical treatment with interbody fusion in combination with fixation. Methods This is a retrospective cohort study. Over a 10 year period at a single institution, all surgically treated patients received surgical debridement, fusion und fixation of the spine to treat PSD. Multi-level cases were either adjacent to each other on the spine or distant. Fusion rates were assessed at 3 and 12 months after surgery. We analyzed demographic data, ASA status, duration of surgery, location and length of spine affected, Charlson comorbidity index (CCI), and early complications. Results A total of 172 patients were included. Of these, 114 patients suffered from single-level and 58 from multi-level PSD. The most frequent location was the lumbar spine (54.0%) followed by the thoracic spine (18.0%). The PSD was adjacent in 19.0% and distant in 81.0% of multi-level cases. Fusion rates at the 3 month follow-up did not differ among the multi-level group (p = 0.27 for both adjacent and distant sites). In the single-level group, sufficient fusion was achieved in 70.2% of cases. Pathogen identification was possible 58.5% of the time. Conclusions Surgical treatment of multi-level PSD is a safe option. Our study demonstrates that there was no significant difference in early fusion outcomes between single-level and multi-level PSD, whether adjacent or distant.
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- 2023
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12. Improved the bias in kernel quantile function estimation
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Abdallah Sayah and Nassima Almi
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bias reduction ,quantile function ,kernel estimation ,order statistics ,bandwidth ,Mathematics ,QA1-939 - Abstract
In this paper, a new estimator for kernel quantile estimation is given to reduce the bias. The asymptotic properties of the proposed estimator was established and it turned out that the bias has been reduced to the fourth power of the bandwidth, while the bias of the estimators considered has the second power of the bandwidth, while the variance remains at the same order. Futhermore, we calculate the optimal bandwidth which minimizes the asymptotic mean squared error. A simulation study and a real data example are carried out to illustrate the performance of the proposed estimator and compared with other existing approaches mentioned.
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- 2023
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13. Vertebroplasty in geriatric patients with osteoporotic vertebral fractures: single-center cohort study at a level 1 center for spinal surgery
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Mohammed Banat, Gregor Bara, Abdallah Salemdawod, Shaleen Rana, Motaz Hamed, Jasmin Scorzin, and Hartmut Vatter
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Osteoporotic vertebral fracture ,Geriatric patients ,Vertebroplasty complication ,Cardiovascular comorbidities ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Abstract Study design Retrospective single-center cohort study. Background The spine is the most common anatomic site for osteoporotic fractures. Osteoporotic vertebral fractures play an increasingly important role in geriatric patients and percutaneous vertebroplasty (PVP) constitutes a common treatment option. The aim of this study was to evaluate the safety and efficacy of PVP in geriatric patients with cardiovascular comorbidities at our center. Methods In this retrospective single-center study, 49 patients aged ≥ 65 with a total of 88 vertebral fractures underwent vertebroplasty. MRI and CT scans of the spine were performed in all patients prior to surgery. All patients were evaluated 4 weeks after surgery as part of their clinical follow-up. VAS scores were recorded before and after the operation. Postoperative complications within 30 days of the initial surgery were analyzed. Results The mean age of patients was 77 years (± 6.4). Of the 49 patients, 39 (80%) were female, and 36 (76%) had cardiovascular comorbidities. The most frequent postoperative complications were cement leakage with no new neurological postoperative deficits (14.3%). The in-hospital mortality rate was 1 out of 49 patients (2%). VAS scores revealed an overall pain reduction of > 97%. None of the following affected patient safety: ASA, BMI, duration of surgery, or the level or localization of vertebroplasty. Conclusions Our data demonstrate that vertebroplasty was a feasible and effective treatment for pain reduction in geriatric patients with osteoporotic fractures despite cardiovascular comorbidities. Level of evidence 3.
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- 2022
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14. التحليل المكاني للخصائص المورفومترية لحوض وادي المهاري في محافظتي النجف والديوانية
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Rana Faeq and Abdallah Sabbar
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وادي المهاري ,الخصائص المورفومترية ,جيومورفولوجيا تطبيقية ,جيومورفولوجيا نهرية ,اودية موسمية ,Language and Literature - Abstract
يعد التحليل المورفومتري مدخلاً لدراسة وفهم العمليات الهيدرولوجية والجيومورفولوجية، اذ يوفر وصفا هندسيا لاحواض وشبكات التصرف المائي على اسس كمية من خلال تطبيق المعادلات او القرائن الرياضية، من اجل تحديد شكل الحوض النهري وخصائصه التضاريسية والمساحية وشبكة الصرف النهري وانماطها، والتي تعكس اثر العوامل الطبيعية للأحواض النهرية كالبنية الأرضية وطبيعة الصخور والخصائص المناخية والتضاريس وكثافة النبات الطبيعي فضلا عن العوامل البشرية، اذ ان لهذه العوامل تأثيرا كبيرا في نشاط عمليات التعرية المائية والترسيب المائي المسؤولة عن صفات وخصائص الحوض نفسه من حيث توسيع الحوض وزيادة مساحته وتحديد شكله والمرحلة الجيومورفولوجية التي وصل اليها والاشكال الارضية. تم استخلاص الخصائص المورفومترية لأحواض التصرف المائي بالاعتماد على نموذج الارتفاع الرقمي DEM وبدقة (30) متر، وبرنامج (Arc Gis 10.8 ). وبعد تحديد الحوض وحساب خصائصه والشبكة النهرية بأستعمال المعادلات الرياضية ووضعها في جداول لابد من تحليلها للافادة منها هيدرولوجيا وجيومورفولوجيا.
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- 2023
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15. A Preliminary Approach towards Rotor Icing Modeling Using the Unsteady Vortex Lattice Method
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Abdallah Samad, Eric Villeneuve, François Morency, Mathieu Béland, and Maxime Lapalme
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UAVs ,rotor icing ,aircraft icing ,cold chamber ,icing wind tunnel ,unsteady vortex lattice method ,Motor vehicles. Aeronautics. Astronautics ,TL1-4050 - Abstract
UAV rotors are at a high risk of ice accumulation during their operations in icing conditions. Thermal ice protection systems (IPSs) are being employed as a means of protecting rotor blades from ice, yet designing the appropriate IPS with the required heating density remains a challenge. In this work, a reduced-order modeling technique based on the Unsteady Vortex Lattice Method (UVLM) is proposed as a way to predicting rotor icing and to calculate the required anti-icing heat loads. The UVLM is gaining recent popularity for aircraft and rotor modeling. This method is flexible enough to model difficult aerodynamic problems, computationally efficient compared to higher-order CFD methods and accurate enough for conceptual design problems. A previously developed implementation of the UVLM for 3D rotor aerodynamic modeling is extended to incorporate a simplified steady-state icing thermodynamic model on the stagnation line of the blade. A viscous coupling algorithm based on a modified α-method incorporates viscous data into the originally inviscid calculations of the UVLM. The algorithm also predicts the effective angle of attack at each blade radial station (r/R), which is, in turn, used to calculate the convective heat transfer for each r/R using a CFD-based correlation for airfoils. The droplet collection efficiency at the stagnation line is calculated using a popular correlation from the literature. The icing mass and heat transfer balance includes terms for evaporation, sublimation, radiation, convection, water impingement, kinetic heating, and aerodynamic heating, as well as an anti-icing heat flux. The proposed UVLM-icing coupling technique is tested by replicating the experimental results for ice accretion and anti-icing of the 4-blade rotor of the APT70 drone. Aerodynamic predictions of the UVLM for the Figure of Merit, thrust, and torque coefficients agree within 10% of the experimental measurements. For icing conditions at −5 °C, the proposed approach overestimates the required anti-icing flux by around 50%, although it sufficiently predicts the effect of aerodynamic heating on the lack of ice formation near the blade tips. At −12 °C, visualizations of ice formation at different anti-icing heating powers agree well with UVLM predictions. However, a large discrepancy was found when predicting the required anti-icing heat load. Discrepancies between the numerical and experimental data are largely owed to the unaccounted transient and 3D effects related to the icing process on the rotating blades, which have been planned for in future work.
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- 2024
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16. Comparative molecular dynamics simulations of pathogenic and non-pathogenic huntingtin protein monomers and dimers
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Mohammed Khaled, Birgit Strodel, and Abdallah Sayyed-Ahmad
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polyglutamine ,huntingtin ,molecular dynamics ,oligomer ,aggregation ,Biology (General) ,QH301-705.5 - Abstract
Polyglutamine expansion at the N-terminus of the huntingtin protein exon 1 (Htt-ex1) is closely associated with a number of neurodegenerative diseases, which result from the aggregation of the increased polyQ repeat. However, the underlying structures and aggregation mechanism are still poorly understood. We performed microsecond-long all-atom molecular dynamics simulations to study the folding and dimerization of Htt-ex1 (about 100 residues) with non-pathogenic and pathogenic polyQ lengths, and uncovered substantial differences. The non-pathogenic monomer adopts a long α-helix that includes most of the polyQ residues, which forms the interaction interface for dimerization, and a PPII-turn-PPII motif in the proline-rich region. In the pathogenic monomer, the polyQ region is disordered, leading to compact structures with many intra-protein interactions and the formation of short β-sheets. Dimerization can proceed via different modes, where those involving the N-terminal headpiece bury more hydrophobic residues and are thus more stable. Moreover, in the pathogenic Htt-ex1 dimers the proline-rich region interacts with the polyQ region, which slows the formation of β-sheets.
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- 2023
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17. Some psychiatric comorbidity among patients with substance abuse disorder related to pregabalin
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Abdallah Saad Ibrahim, Reem Hassan Bayomy, Ramadan Abdelbr Hussein, Usama Mahmoud Yousef, and Waleed Eleraky Elazab
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Pregabalin ,Abuse ,Psychiatric comorbidity ,Psychiatry ,RC435-571 - Abstract
Abstract Background Pregabalin abuse is increasing worldwide and frequently comorbid with another psychiatric disorders including generalized anxiety, major depression, personality disorders, and suicide. Eighty-three patients meeting DSM-IV criteria for substance abuse disorders related to pregabalin were identified from the addiction clinic of El Khanka Psychiatric Hospital in Egypt for this observational cross-sectional study. We aimed to assess clinical characteristics of substance abuse disorder related to pregabalin, suicidal ideation, and psychiatric comorbidities associated with them. All participants were subjected to semi-structured interview designed to collect and identify the sociodemographic data and patterns of substances use, the Structured Clinical Interview for DSM-IV axis I disorders to diagnose comorbid major depression and generalized anxiety, Structured Clinical Interview for DSM-IV axis II disorders for diagnosis of borderline and antisocial personality disorders, Addiction Severity Index, Beck Depressive Inventory, Hamilton Anxiety Rating Scale, and Beck Scale for Suicidal Ideation and urine screening test for pregabalin and other substances. Results Forty-seven percent of the studied group had generalized anxiety disorder, 74.7% had major depression disorder, some patients had both major depression and generalized anxiety disorders, 78.3% had borderline personality disorder, 37.3% had antisocial personality disorder, and some patients had both borderline and antisocial personality disorders. There was a statistically significant increase in suicidal ideation among subjects with major depression, generalized anxiety, previous suicidal attempts, and borderline personality disorder. Conclusions There is a high comorbidity between pregabalin abuse and major depression disorder, generalized anxiety disorder, borderline personality disorder, and antisocial personality disorder. These psychiatric comorbidities were associated with high risk of suicidal ideations.
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- 2022
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18. Suicidal ideation and behavior among subjects with substance abuse disorder related to pregabalin
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Abdallah Saad Ibrahim, Reem Hassan Bayomy, Ramadan Abdelbr Hussein, Usama Mahmoud Yousef, and Waleed Eleraky Elazab
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Pregabalin ,Abuse ,Suicide ,Psychiatry ,RC435-571 - Abstract
Abstract Background Although pregabalin abuse is increasing worldwide and may be associated with increased suicidal ideation and behavior, few studies were done in Egypt searching for the effect of pregabalin on suicide. Eighty-three patients meeting DSM-IV criteria for substance abuse disorders related to pregabalin were identified from the addiction clinic of EL Khanka Psychiatric Hospital in Egypt for this observational cross–sectional study. We intended to assess suicidal ideation and behavior in patients with substance abuse disorder related to pregabalin and to identify the effects of other comorbid substances of abuse. All participants were subjected to semi-structured interview designed to collect and identify the socio-demographic data and patterns of substances 'use ,The Structured Clinical Interview for DSM-IV Axis I Disorders to diagnose patients with substance abuse disorder “related to pregabalin,” Beck Scale for Suicidal Ideation for assessment of suicidal ideation and behavior and urine screening test for pregabalin and other substances of abuse. Results Most of participants used pregabalin continuously {86.7%}. More than seventy nine percent of the patients abused both pregabalin and other substances, tramadol 67.4%, heroin 66.3%, cannabis 65.1%, other drugs 44.6%, and benzodiazepines 27.7%. Screening urine test was positive in 62.7% of participants most frequently was heroin 41% and cannabis 34.9%. No suicidal ideation was found in 67.4%, 19.3% had low risk of suicide, and 13.3% had high risk of suicide so total participants who had suicidal ideation were 32.6%. There was statistical significant increase in risk of suicide among patients who were continuously abusing pregabalin and who had positive pregabalin urine test. There was significant positive correlation between Beck Suicidal Ideation score and duration of abusing pregabalin, maximum and daily dose of pregabalin. Also, there was a statistical significant relation between suicidal ideation and associated tramadol abuse and this was positively correlated with dose and duration of tramadol abuse. Conclusions About one third of patients abusing pregabalin had a risk of suicide and this risk increased with associated tramadol abuse so pregabalin abuse is dangerous like other substances of abuse and must be used with caution under strict medical supervision
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- 2022
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19. Socio-demographic and clinical correlates of parenting style among parents having ADHD children: a cross-section study
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Ghada Mohamed Salah El-Deen, Amira Mohamed Yousef, Amany Elshabrawy Mohamed, and Abdallah Saad Ibrahim
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ADHD ,Children ,Parenting style ,Psychiatry ,RC435-571 - Abstract
Abstract Background ADHD affects 7.8% of the school-aged population, making it one of the most common childhood brain illnesses. It is characterized by abnormally high levels of inattention, activity, and impulsivity at a young age. Being a parent of a child with ADHD is a real challenge, as the parents tend to be more disapproving, critical, and provide more impulse control directions; such parenting style can have an impact on the illnesses course, accentuate its signs and symptoms, and lead to secondary development of co-morbid psychiatric and behavioral problems. This makes the parent-child effect a matter of clinical importance that needs to be carefully assessed and managed. We aimed to estimate the sociodemographic and clinical correlates of parenting attitudes among parents having ADHD children. This cross-sectional study included 48 ADHD children from both sexes, aged from 6 to 12 years old, and their parents. In our study, we applied the Stanford-Binet Intelligence Scale 5th edition, the Conner’s Parent Rating Scale-revised, the parenting style as perceived by children questionnaire, and the Fahmy and El-Sherbini questionnaire for the measurement of socioeconomic status. Results Mothers of ADHD children had significantly lower scores of over-protections parenting style than the fathers; the current study showed a significant increase in total parenting scores and warmth/support in mild ADHD cases than in moderate and severe ones, and there is a significant increase in the mother’s positive parenting style toward ADHD children with lower levels of social problems, mild cases, and older age. There is a significant increase of positive parenting style toward ADHD children exerted by post graduated, professionally working, and high social class fathers and by working mothers among rural residents and high social class mothers. There is a positive correlation between IQ and a mother’s warmth/support. Conclusion ADHD children with mild symptoms, higher social functioning of the child, high socioeconomic level of the family, better education, and professional occupations of parents were associated with positive parenting style.
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- 2021
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20. The use of plant (Citrullus colocynthis) in alternative medicine
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Abdallah Sabaar Abood, Phd and Hussam Kanaan Waheed, Phd.
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plant ,Biogeography ,Citrullus colocynthis ,alternative medicine ,Plant of geography ,Language and Literature - Abstract
Alternative medicine is one of the most important choices for humans, as many people are going to live closer to nature, because they have seen good results for most herbs that replace the chemical drugs that have greatly affected the human body. The research investigates the historical facts of alternative medicine, the use of Citrullus colocynthis, the treatment of many diseases, the geographical distribution of plants in Iraq, and the proposal to invest in plants in Iraq.
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- 2022
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21. Independent Component Analysis of Functional Magnetic Resonance Imaging Data Using Wavelet Dictionaries
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Johnson, Robert, Marchini, Jonathan, Smith, Stephen, Christian F. Beckmann, Davies, Me, James, Cj, Abdallah, Sa, Plumbley, Md, Davies, M, James, C, Abdallah, SA, and Plumbley, MD
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Discrete wavelet transform ,medicine.diagnostic_test ,business.industry ,Computer science ,Pattern recognition ,Independent component analysis ,Regression ,Wavelet ,Robustness (computer science) ,medicine ,Computer vision ,Artificial intelligence ,Noise (video) ,Functional magnetic resonance imaging ,business ,Curse of dimensionality - Abstract
Functional Magnetic Resonance Imaging (FMRI) allows indirect observation of brain activity through changes in blood oxygenation, which are driven by neural activity. ICA has become a popular exploratory analysis approach due its advantages over regression methods in accounting for structured noise as well as signals of interest. However, standard ICA in FMRI ignores some of the spatial and temporal structure contained in such data. Using prior knowledge that the Blood Oxygenation Level Dependent (BOLD) response is spatially smooth and manifests itself on certain spatial scales, we estimate the unmixing matrix using only the coarse coefficients of a 3D Discrete Wavelet Transform (DWT). We utilise prior biophysical knowledge that the BOLD response manifests itself mainly at the spatial scales we use for unmixing. Tests on realistic synthetic FMRI data show improved accuracy, greater robustness to misspecification of underlying dimensionality, and an approximate fourfold speed increase; in addition the algorithm becomes parallelizable. © Springer-Verlag Berlin Heidelberg 2007.
- Published
- 2007
22. الخصائص الهيدرولوجية لحوض الشرهاني واحواضه الثانوية باستخدام برنامج (HEC-HMS)
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Fatma Ali A. Kazem and Abdallah Sabbar Abood, PHD
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(HEC – HMS) ,حجم الجريان السطحي ,ذروة التصريف الاقصى ,زمن التركيز ,Language and Literature - Abstract
تفتقر الاودية في المناطق الجافة الى مزيد من الدراسات والابحاث التي تمكن اصحاب القرار من التعرف على جوانبها وخصائصها المختلفة تمهيداً لاستغلالها وتنمية مصادر المياه ومشاريع التنمية وذلك في المناطق التي لا تتوفر فيها محطات هيدرولوجية لقياس الجريان السطحي، إذ يتم الاعتماد على التخمين لتقدير الجريان السطحي، لذلك سيتم استخدام أنموذج (HEC - HMS) الهيدرولوجي وهي من افضل الطرق وادقها إذ تثبت العلاقة بين المطر والجريان السطحي، حيث وضعت هيئة المهندسين في الجيش الأمريكي هذه الطريقة لقياس تساقط الامطار والمأخوذة من جداول خاصة ، وهي من اهم العوامل في اعداد خريطة المجاميع الهيدرولوجية لتربة حوض الشرهاني واحواضه الثانوية .
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- 2022
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23. Attitude of Students Towards the Study of Physics: A Case of Tamale College of Education, Ghana.
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Moses Kojo Asare Mabee, Tahiru Zingani Haruna, and Abdallah Salifu
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physics ,attitude ,students ,tutor ,positive ,negative. ,Education - Abstract
The study examined the attitude of third-year science and mathematics students towards the study of Physics in the Tamale College of Education, Ghana. A case study involving a sample of one hundred and thirty–three students was adopted for the study. Using a structured questionnaire, data was collected from the selected sample. The Likert rating scale was adopted to indicate the extent of agreement or disagreement. General findings from the study indicated that the majority of the respondents had a negative perception towards the study of Physics. The research recommended that preferably only students who offered Elective Physics at the Senior High School level should be admitted to study Physics at the College level as this would facilitate the smooth teaching and learning of the subject. It was also suggested that Physics tutors should use innovative strategies to make the teaching and learning of the subject interesting and attractive.
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- 2021
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24. Serum BDNF and suicidal ideation in drug-naïve and drug-treated MDD patients: a case–control study
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Amira Mohamed Yousef, Ghada Mohamed Salah El-Deen, Abdallah Saad Ibrahim, and Amany Elshabrawy Mohamed
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BDNF ,Suicidal ideation ,MDD ,Drug-naïve ,Drug-treated ,Neurogenesis ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Abstract Background Disturbances in structural and synaptic plasticity have been linked to depression and suicidal ideation. One of the major neurotrophic factors, the brain-derived neurotrophic factor (BDNF), is involved in the maintenance and survival of neurons and synaptic plasticity. This case–control study assesses the serum BDNF and suicidal ideation among drug-naïve and drug-treated MDD patients attending university hospitals and comparing them to healthy control. A simple random sample of 57 MDD patients and 57 age- and sex-comparable controls were enrolled. The researchers conducted a semi-structured interview to collect the demographic characteristics and disease history. Structured Clinical Interview for DSM-5 (SCID-5), Hamilton Depression Rating Scale (HDRS), and Beck Scale for Suicidal Ideation (BSS) were applied to the participants. Blood samples were collected to measure plasma BDNF level. Results The MDD group had lower BDNF than the control group. Within the MDD group, drug-naïve patients had significantly lower BDNF than drug-treated patients. Female patients had lower BDNF than male patients. Positive family history of MDD was associated with low BDNF. Severe and moderate cases had lower BDNF than mild cases. High BSS (≥24) was associated with low BDNF. A statistically significant positive correlation was found between BDNF and age, disease duration, duration of the current episode, and the number of previous episodes. On the other hand, a statistically significant negative correlation was found between BDNF and age of MDD onset, HDRS, and BSS. A regression model was highly statistically significant in the prediction of HDRS. BDNF and disease duration were negatively correlated with HDRS. On the other hand, depression treatment status was not significantly associated with the HDRS prediction model. Conclusion Our findings extend the neurotrophic concept of depression by identifying the decreased BDNF levels as a peripheral biomarker of MDD. Our assessment of depression and suicidal ideation (SI) and their relationship to decreased BDNF levels shed light on the etiopathology of MDD and its related suicidality. They should be more studied to understand better the mechanisms by which they develop. To further explore the effect of BDNF in suicide, larger study sizes and a range of psychiatric diagnoses associated with suicide attempts are required.
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- 2021
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25. Predictive Information Rate in Discrete-time Gaussian Processes
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Abdallah, SA and Plumbley, MD
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Computer Science::Cryptography and Security - Abstract
We derive expressions for the predicitive information rate (PIR) for the class of autoregressive Gaussian processes AR(N), both in terms of the prediction coefficients and in terms of the power spectral density. The latter result suggests a duality between the PIR and the multi-information rate for processes with mutually inverse power spectra (i.e. with poles and zeros of the transfer function exchanged). We investigate the behaviour of the PIR in relation to the multi-information rate for some simple examples, which suggest, somewhat counter-intuitively, that the PIR is maximised for very `smooth' AR processes whose power spectra have multiple poles at zero frequency. We also obtain results for moving average Gaussian processes which are consistent with the duality conjectured earlier. One consequence of this is that the PIR is unbounded for MA(N) processes.
- Published
- 2012
26. Diet Supplemented With Purslane, Portulaca oleracea Linnaeus, 1753 Resolves Bisphenol A Impact on North African Catfish, Clarias gariepinus (Burchell, 1822)
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HODA MOHAMED LOTFY ABDALLAH, SAHAR NASR MOHAMEDY, ABDALLAH SAID HAMED, MOHAMED AHMED BAKRY, MAGDA NEMAT ABDELAL, and SOAD MEKAWY
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Aquaculture. Fisheries. Angling ,SH1-691 - Abstract
Bisphenol A (BPA) is one of the most widely used synthetic compounds in the world. Since BPA is a suspected xenoestrogen and oxidative stressful agent, its potential hazardous impacts were evaluated on the health and the reproductive status of the male North African catfish, Clarias gariepinus (Burchell, 1822). Ninety mature male North African catfish were divided into six groups (in three replicates); Group 1 & Group 4 fed basal diet (control), Group 2 & Group 5 diets supplemented with 3 % purslane, Portulaca oleracea Linnaeus, 1753 powder, and Group 3 & Group 6 diets supplemented with 5 % purslane powder. Group 4, Group 5, and Group 6 were exposed to 50 µg.L-1 BPA for 14 days. Group 4 showed a significant increase in the luteinising hormone, 17β estradiol, and malondialdehyde levels, with a decrease in the testosterone, superoxide dismutase, and catalase concentrations. Simultaneously, there were elevated liver and kidney markers with severe degenerative changes in the testes, liver, and kidney. Dietary supplementation of purslane powder returned the measured parameters to their normal values with the correction of the tissue architectures and details. Interestingly, purslane in the non-BPA treated groups raised the testosterone and 17β estradiol over the control values. It is suggested that purslane could be used in aquaculture and cultivated near polluted water areas.
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- 2022
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27. Stock market prediction based on statistical data using machine learning algorithms
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Md. Mobin Akhtar, Abu Sarwar Zamani, Shakir Khan, Abdallah Saleh Ali Shatat, Sara Dilshad, and Faizan Samdani
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Machine learning data pre-processing ,Statistics ,SVM ,Science (General) ,Q1-390 - Abstract
The main perfect of this composition is to discover the stylish version to prognosticate the cost of the inventory request. During the procedure of analyzing the colorful ways and variables to remember, we plant that approaches similar as Random woodland, machine help Vector were not absolutely exploited. On this composition, we will introduce and assessment a in addition practicable gadget to prognosticate the motion of shares with lesser delicacy. The first issue we looked at turned into the previous time's stock price dataset. The dataset has been preprocessed and refined for actual analysis. For this reason, our composition can even focus on preprocessing the raw data of the dataset. 2nd, after preprocessing the facts, we are able to observe the use of the arbitrary wood, we can aid the vector machine on the dataset and the results it generates. Similarly, the proposed composition examines the use of the soothsaying device in actual surrounds and the problems related to the delicacy of the overall values handed. The composition additionally provides a system literacy version for prognosticating the lifestyles of shares in a aggressive request. Predicting the success of shares might be a main asset for stock request institutions and could give actual effects to the troubles facing equity investors. By Using Stock Prediction algorithm overall accuracy is 80.3%.
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- 2022
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28. Correlation between Blood Type 0 and Risk of Chronic Subdural Hematoma Recurrence: A Single Center Retrospective Cohort Study
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Motaz Hamed, Tim Lampmann, Abdallah Salemdawod, Harun Asoglu, Naomi Houedjissin, Marcus Thudium, Lakghomi Asadeh, Frederic Carsten Schmeel, Fabiane Schuch, Hartmut Vatter, and Mohammed Banat
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chronic subdural hematoma ,ABO blood type ,minor head trauma ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Chronic subdural hematoma (cSDH) is a common disease in the neurological and neurosurgical world. The recommended treatment for cSDH patients with moderate or severe neurological symptoms is surgical evacuation, but cSDH frequently recurs. The patient’s ABO blood type may influence the outcome. This study aims to evaluate the correlation between cSDH recurrence and blood type O. We performed a retrospective analysis of the data of patients with cSDH who were surgically treated. Recurrence was defined as the need for re-operation within the first 12 weeks after the initial surgery. We analyzed standard demographic data, duration and type of surgery, ABO blood types, and the re-operation rate. Univariate and multivariate analyses were conducted. A total of 229 patients were included. The recurrence of hematoma was identified in 20.5% of patients. Blood type O was found to be significantly associated with cSDH recurrence leading to re-operation within 12 weeks (p = 0.02, OR 1.9, 95% CI 1.1–3.5). Thrombocyte aggregation inhibition and oral anticoagulants were not predictors of cSDH recurrence. Patients with blood type O in our cohort were identified to be at higher risk of cSDH recurrence and may, therefore, be a more vulnerable patient group. This finding needs further evaluation in larger cohorts.
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- 2023
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29. Embodied Carbon Minimization for Single-Story Steel Gable Frames
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Abdallah Salama, Assem Atif Farag, Atef Eraky, Alaa A. El-Sisi, and Rania Samir
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meta-heuristic optimization ,gable frames ,non-prismatic members ,optimal frame configuration ,embodied carbon ,Building construction ,TH1-9745 - Abstract
As the construction industry, especially steel construction, contributes to a large portion of global greenhouse gas emissions, sustainable structural design has become a necessity to achieve the world vision of reaching net zero emissions by 2050. As steel portal frames are the most used structural system for single-story buildings, the main objective of this study is to determine the optimal steel portal frame configuration using prismatic and/or non-prismatic members to achieve the least embodied carbon. Five different portal frame configurations are considered under the effect of five distinct loading conditions. The results led to developing design charts consisting of contour plots showing the embodied carbon per unit of volume enclosed by the steel frame for different frame configurations, loading conditions, span lengths, and column heights. In addition, by increasing the number of member divisions, design variables, and non-prismatic segments, the average embodied carbon of the steel portal frames can be significantly reduced by about 14.34% up to 26.47% relative to the configuration with only prismatic members.
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- 2023
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30. C-reactive protein and clinical subtypes of major depressive disorder at Zagazig University Hospitals
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Amany Elshabrawy Mohamed, Rafik Reda Abd El-Latif, Amira Mohamed Youssef, and Abdallah Saad Ibrahim
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C-reactive protein ,Depression subtypes ,Suicidality ,Psychiatry ,RC435-571 - Abstract
Abstract Background Although, the relation between inflammation and major depressive disorder (MDD) looks like firm, it may not exist in all patients with depression. Therefore, the main aim of this study was to compare serum C-reactive protein (CRP) level among clinical subtypes of MDD and its relation with suicidality. Results According to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for MDD, 98 patients included and categorized into five clinical subtypes groups: atypical, anxious, melancholic, psychotic, and unspecified depression with percent (11.2%, 31.6%, 19.4%, 15.3%, and 22.4%) respectively. Twenty-four (24.5%) of all patients had suicidal thoughts using Beck Scale for Suicidal Ideation (BSS) with statistically significant increase (P < 0.05*) in suicidality among atypical group. On assessing CRP level, there was highly statistical significant increase (P < 0.001**) among cases with atypical type and also cases with suicidal ideation. Also, logistic regression analysis found that the significant predictors for high CRP among the studied cases were smoking, suicidality, atypical depression, and suicide depression. Conclusions Higher level of CRP was found among patients with atypical MDD, and there was significant relationship between CRP and suicidality.
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- 2020
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31. HPCCloud Seer: A Performance Model Based Predictor for Parallel Applications on the Cloud
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Abdallah Saad and Ahmed El-Mahdy
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Cloud computing ,high performance computing ,message passing interface ,performance modeling ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
With the continual increase in the high performance computing (HPC) market share, the need for a cheaper and widely available system rather than the expensive typical HPC systems increases. A promising alternative to HPC typical systems is the cloud computing environment which is characterised by being cheap, flexible, scalable and available. However, the cloud is based on virtualization which increases the latency to access the processing and network resources due to resource sharing. This makes the cloud an unpredictable environment to long run time programs such as HPC applications. Hence, modelling and understanding performance is essential for exploiting such environment. In this paper we propose a predictor for the execution time of the message passing interface (MPI) based applications on the cloud, as they are a major class of HPC applications. The predictor is based on an analytical performance model through considering the cloud resources as a queueing network, and the parallel applications as jobs contesting for the shared resources. The prediction based on the proposed model is measured on both a cluster of bare-metal servers and on a group of virtual machines. The overall accuracy of this prediction is 88% for 10 benchmarks, 5 from SPEC-MPI and 5 from NASA parallel benchmarks.
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- 2020
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32. Glycemic control in an undiagnosed diabetes mellitus patient with Coronavirus Disease 2019
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Nwawueze Andrew Efam Okonta, Taofeek Oloyede, Olayinka Rasheed Ibrahim, Bashir Olajide Yusuf, Abdallah Sanda, and Bello Muhammed Suleiman
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coronavirus disease 2019 ,glycemic control ,undiagnosed diabetes mellitus ,Medicine - Abstract
Diabetes mellitus in coronavirus disease 2019 (COVID-19) patients is associated with poor outcomes due to poorly understood reasons inclusive of blood sugar patterns. Hence, we report a case of a 52-year-old Nigerian man known hypertensive heart disease patient, previously undiagnosed diabetes mellitus patient with difficulty in blood sugar control, heart failure, and persistent severe acute respiratory syndrome coronavirus 2 8 weeks after he tested positive. A 52-year-old male civil servant obese, known hypertensive heart disease patient presented with complaints of fever, cough, difficulty with breathing, headache, and generalized body weakness. At presentation, he had respiratory distress with low oxygen saturation of 78% and hyperglycemia (blood sugar of 40 mmol/l). His body mass index was 35.9 kg/m2. Chest radiography showed ground-glass appearance with cardiomegaly. Over the next 10 days on admission, his blood sugar fluctuated between hyperglycemia and an episode of hypoglycemia with occasional euglycemia and had glycated hemoglobin of 10.8%. The full blood count was normal, electrolyte, urea and creatinine showed mild elevation of the urea and creatinine, other parameters were normal, while the lipid profile showed hypercholesterolemia. He received multiple doses of insulin, anti-hypertensive, lopinavir/ritonavir, methylprednisolone, and azithromycin. The patient was weaned off oxygen after 10 days and discharged home 15 days after admission. This case report highlighted the challenges that may face a patient with undiagnosed diabetes mellitus and COVID-19. It also brings forth the need to expand research options in COVID-19 and risk factors associated with the disease as the world strives to control the global pandemic.
- Published
- 2020
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33. Antithrombotic Therapy in Spinal Surgery Does Not Impact Patient Safety–A Single Center Cohort Study
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Mohammed Banat, Johannes Wach, Abdallah Salemdawod, Gregor Bara, Ehab Shabo, Jasmin E. Scorzin, Martin Müller, Hartmut Vatter, and Lars Eichhorn
- Subjects
spinal surgery ,spinal complications ,antithrombotic therapy ,patient safety ,optimizing surgical planning ,Surgery ,RD1-811 - Abstract
ObjectiveAntithrombotic therapy is common in older patients to avoid thromboembolic events. Careful planning is required, particularly in the perioperative environment. There are no clearly date guidelines on the best timing for interrupting the use of anticoagulation in the case of spinal surgery. This study evaluates early per procedural clinical outcomes in patients whose antithrombotic therapy was interrupted for spinal surgery.MethodsThis is a retrospective cohort study. All patients who underwent dorsal instrumentation from January 1, 2019 to December 31, 2020 were included. In group A, vitamin K antagonists (VKA) were suspended for 5 days and direct oral anticoagulants (DOAC) for 3 days. In group B, antiplatelet agents (APA) were paused for at least 7 days before surgery to prevent perioperative bleeding. Patients not taking anticoagulation medication were gathered into control group C. We analyzed demographic data, ASA status, blood loss, comorbidities, duration of surgery, blood transfusion, length of hospital stay, complications, thromboembolism, and 30 day in-hospital mortality. Multivariate analyses from the three groups were further analyzed and conducted.ResultsA total of 217 patients were operated and included. Twenty-eight patients taking VKA/DOAC (group A), 37 patients using APA (group B), and 152 patients without anticoagulation (group C) underwent spinal surgery. Those using anticoagulants were significantly older and often with multimorbidity, but did not differ significantly in procedural bleeding, time of surgery, length of hospital stay, complication rate, thromboembolism, or 30 day in-hospital mortality (p > 0.05).ConclusionOur data show that dorsal instrumentation safely took place in patients whose antithrombotic therapy was interrupted.
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- 2022
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34. Knowledge, Attitudes, and Practices Related to Antibiotic Use and Antibiotic Resistance among Poultry Farmers in Urban and Peri-Urban Areas of Ouagadougou, Burkina Faso
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Abdallah Sawadogo, Assèta Kagambèga, Arshnee Moodley, Abdoul Aziz Ouedraogo, Nicolas Barro, and Michel Dione
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knowledge ,attitudes ,practices ,antimicrobial resistance ,chicken ,west Africa ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Increased use of antibiotics in livestock is a public health concern, as it poses risks of antibiotic residues and antibiotic-resistant pathogens entering the food chains and infecting humans. A cross-sectional survey was conducted on 216 poultry farms to study knowledge, attitudes and practices of poultry farmers on the use of antibiotics in urban and peri-urban areas of Ouagadougou. Results show that only 17.13% (37/216) of farmers attended training on poultry production. Majority of farmers—85.65% (185/216) were not knowledgeable about the rational use of antibiotics. When there was a disease outbreak, 31.98% (63/197) of farmers used veterinary drugs without a prescription and 22.34% (44/197) consulted a community animal health worker. It should also be noted that 79.19% (156/197) of farmers reported using chicken meat as per normal if the bird died during or right after treatment with an antibiotic. Knowledge of rational use of antibiotics was positively influenced by a good attitude adopted by the farmer during the illness of birds and negatively influenced by disease treatment success and high level of education of the farmer. Lack of knowledge about the rational use of antibiotics including their use without a prescription are serious risk factors for the emergence of antimicrobial resistance. Awareness of farmers and other veterinary drug supply chain actors such as drug stockists and animal health workers on best practices in antimicrobial use and promotion of good biosecurity on farms are important to reduce the misuse of antibiotics.
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- 2023
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35. Editorial: Coronavirus Disease (COVID-19): Pathophysiology, Epidemiology, Clinical Management and Public Health Response
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Denise L. Doolan, Zisis Kozlakidis, Zhongheng Zhang, Slobodan Paessler, Longxiang Su, Yasuko Tsunetsugu Yokota, Tatsuo Shioda, Alexander Rodriguez-Palacios, Ata Murat Kaynar, Rukhsana Ahmed, Abdallah Samy, Hannah Bradby, Alexis M. Kalergis, Mohan Jyoti Dutta, Michael Kogut, and Shen-Ying Zhang
- Subjects
coronavirus—COVID-19 ,first wave ,pathophysiology ,epidemiology ,clinical management ,public health response ,Public aspects of medicine ,RA1-1270 - Published
- 2021
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36. Experimental Investigation of Icing Effects on a Hovering Drone Rotor Performance
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Eric Villeneuve, Abdallah Samad, Christophe Volat, Mathieu Béland, and Maxime Lapalme
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icing ,drones ,UAV ,hover flight ,VTOL ,Motor vehicles. Aeronautics. Astronautics ,TL1-4050 - Abstract
A scaled version of the APT70 drone rotor, typical of small to medium UAV rotors, was tested in a 9-meter-high cold chamber for a wide range of icing parameters. The drone rotor used has four blades with varying chord and twist settings. The objective of this study was to investigate icing effects on the rotor aerodynamic performance, based on experimental data, for varying rotor speeds, precipitation rates, droplet sizes and air temperatures. Aerodynamic loads were measured using the built-in load cell, and data were compared to photographs taken during testing as well as ice thickness measurements at the end of tests. The impact of each test parameter and their variations on the degradation of the rotor’s performances was evaluated. The results show that larger droplets and lower RPMs and pitch angles generate a more rapid degradation of the performances due to the airflow around the blades and tip-vortex affecting the collection efficiency of the blades. With the smaller droplets, the air temperature did not affect the performance degradation, only the type of ice accumulation. However, with the larger droplets, degradation of the performances was less severe at warmer temperatures since almost no ice accumulated at the tip and droplets were expelled before freezing.
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- 2022
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37. Can Postoperative CT Imaging in Spine Surgery Be Replaced by Intraoperative 3D Rotation With the C-Arm?: Results of a Prospective Single Center Cohort Study
- Author
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Mohammed Banat, Johannes Wach, Abdallah Salemdawod, Lisa Domurath, Jasmin Scorzin, and Hartmut Vatter
- Subjects
spinal surgery ,patient safety ,screw accuracy ,technologies in spinal surgery ,intraoperative navigation ,Surgery ,RD1-811 - Abstract
Objective: Dorsal instrumentation of the spine is an established treatment option for a range of spinal pathologies. Intraoperative fluoroscopy connected with navigation minimize the risk of incorrect screws placement. In several cases, post-operative CT scans are needed to verify possible mismatches. In this study, we evaluated the efficacy of 3D intraoperative fluoroscopy as compared to post-operative CT and the need of post-operative CT.Methods: We conducted a prospective single-center cohort study, 94 patients were included. The screws were implanted using 3D rotation with C-arm and navigation system. The definitive position of the screws was verified by a post-operative CT scan. Finally, we compared the discrepance between intraoperative imaging and post-operative CT scan using Rampersaud-grade (A-D).Results: 607 screws in 94 patients were included. Some 3% of the screws had to be replaced immediately intraoperative due to inadequate position with lateral or medial trajectory. An A-score was achieved for 85.5% of the 3D controlled screws and 87% of the post-operative CT. A B-score was found in 11.5% of either groups. In the 3D group a C-score was achieved for 2.5% and in the CT group for 0.8%. A D-score was found in 0.5% of the screws in both groups, p = 0.45. Only a mismatch of 3% could be detected for the intraoperative and post-operative imaging results.Conclusion: Our study data shows that the placement of screws using the 3D rotation and navigation tool is safe and accurate. There were no relevant mismatches between intraoperative images and the post-operative CT.
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- 2021
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38. Remediation of Copper and Zinc from wastewater by modified clay in Asir region southwest of Saudi Arabia
- Author
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Abdallah Samy
- Subjects
heavy metals removal ,i.r spectroscopy ,modified kaolinite ,s.e.m ,wastewater treatment ,Geology ,QE1-996.5 - Abstract
To investigate the efficacy of modified clay minerals to remediate heavy metals from industrial wastewater, two natural clay sediments dominated by kaolinite were selected. Since the kaolinite clay has low cation exchange capacity, some modifications were made using unusual treatments thermal transformation and acid activation techniques were used to increase exchangeability properties for producing modified kaolinite. The increased exchangeability was demonstrated through various methods. Results of X-Ray diffraction analysis verified the transformation of Kaolinite as indicated from disappearing all the diffractogram peaks due to kaolinite. In infra-red spectroscopy, the presence of a broad band with little change in the intensity in the region coupled with broad Si-O bending vibration band and Si-O-Al compound vibration bands explain the extent of structural disorder as a response of modification treatment. From a mineral structural viewpoint, destruction through heat treatment exposes directed –OH bonds located between the tetrahedral and octahedral layers (amorphization). It has been observed that after an acidification treatment, the –OH groups become less stable and lead to the newly formed vacant sites during the modification treatments accommodate extra structural water; thereby; broadening the –OH bands in the I.R spectrum.
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- 2019
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39. A Validation Study for SHE Score for Acute Subdural Hematoma in the Elderly
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Martin Vychopen, Motaz Hamed, Majd Bahna, Attila Racz, Inja Ilic, Abdallah Salemdawod, Matthias Schneider, Felix Lehmann, Lars Eichhorn, Christian Bode, Andreas H. Jacobs, Charlotte Behning, Patrick Schuss, Erdem Güresir, Hartmut Vatter, and Valeri Borger
- Subjects
subdural ,hematoma ,acute ,nonconvulsive ,status ,epilepticus ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Objective: The aim of this study was the verification of the Subdural Hematoma in the Elderly (SHE) score proposed by Alford et al. as a mortality predictor in patients older than 65 years with nontraumatic/minor trauma acute subdural hematoma (aSDH). Additionally, we evaluated further predictors associated with poor outcome. Methods: Patients were scored according to age (1 point is given if patients were older than 80 years), GCS by admission (1 point for GCS 5–12, 2 points for GCS 3–4), and SDH volume (1 point for volume 50 mL). The sum of points determines the SHE score. Multivariate logistic regression analysis was performed to identify additional independent risk factors associated with 30-day mortality. Results: We evaluated 131 patients with aSDH who were treated at our institution between 2008 and 2020. We observed the same 30-day mortality rates published by Alford et al.: SHE 0: 4.3% vs. 3.2%, p = 1.0; SHE 1: 12.2% vs. 13.1%, p = 1.0; SHE 2: 36.6% vs. 32.7%, p = 0.8; SHE 3: 97.1% vs. 95.7%, p = 1.0 and SHE 4: 100% vs. 100%, p = 1.0. Additionally, 18 patients who developed status epilepticus (SE) had a mortality of 100 percent regardless of the SHE score. The distribution of SE among the groups was: 1 for SHE 1, 6 for SHE 2, 9 for SHE 3, and 2 for SHE 4. The logistic regression showed the surgical evacuation to be the only significant risk factor for developing the seizure. All patients who developed SE underwent surgery (p = 0.0065). Furthermore, SHE 3 and 4 showed no difference regarding the outcome between surgical and conservative treatment. Conclusions: SHE score is a reliable mortality predictor for minor trauma acute subdural hematoma in elderly patients. In addition, we identified status epilepticus as a strong life-expectancy-limiting factor in patients undergoing surgical evacuation.
- Published
- 2022
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40. Design approach for interceptor tile drains using hydrus
- Author
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Ahmed Mohamed Tawfik and Abdallah Sadik Bazaraa
- Subjects
Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Seepage from irrigation canals can be controlled by interceptor pipe drains located down slope of the canal embankment and parallel to the canal. HYDRUS (2D/3D) is a software that simulates water flow in two-dimensional variably-saturated porous media. This software is used to determine the average water contents of the upper layers, direction of flow and the seepage rate to the pipe drain for different values of evaporation rates, pipe diameters, and horizontal and vertical pipe offsets from the conveyance canal. The results showed that increasing the vertical offset (drain depth) increases the drain discharge. Moreover, increasing the horizontal offset reduces the canal seepage and lower the phreatic surface. The proposed approach can determine drain size and location to cut off canal seepage, ensuring no contribution to the water body under the irrigated lands beyond the drain. The approach accounts for realistic soil formations and considers both saturated and capillary flows. Keywords: Interceptor drains, Canal seepage, Hydrus
- Published
- 2018
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41. An Experimental Apparatus for Icing Tests of Low Altitude Hovering Drones
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Eric Villeneuve, Abdallah Samad, Christophe Volat, Mathieu Béland, and Maxime Lapalme
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aerospace ,icing ,drones ,UAV ,experimental setup ,cold room ,Motor vehicles. Aeronautics. Astronautics ,TL1-4050 - Abstract
The icing facilities of the Anti-Icing Materials International Laboratory AMIL have been adapted to reproduce icing conditions on a Bell APT70 drone rotor, typical of small-to-medium UAV models. As part of an extensive icing test campaign, this paper presents the design and preliminary testing of the experimental setup and representative icing conditions calibration in the laboratory’s cold chamber. The drone rotor used has four blades with a diameter of 0.66 m and a maximum tip speed of 208 m/s. For the icing conditions, freezing rain and freezing drizzle were selected. A Liquid Water Content (LWC) calculation methodology for a rotor in hover was developed, and procedures to determine experimental LWC in the facility are presented in this paper. For the test setup, the cold chamber test section was adapted to fit the rotor and to control its ground clearance. Testing was aimed at studying the effect of rotor height h on aerodynamic performance, both with and without icing conditions. Results show no significant effect on the ground effect between h = 2 m and h = 4 m in dry runs, while the icing behavior can be largely influenced for certain conditions by the proximity of the precipitation source, which depend on the height of the rotor in these experiments.
- Published
- 2022
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42. The Nitrification Capacity of Different Types of Biological Filters - An Overview
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Ahmed EL-SHESHTAWY, Abdallah SALAH, Mostafa Abdel RAHMAN IBRAHIM, Dorina Nicoleta MOCUTA, Adrian TUREK RAHOVEANU, and Ana Maria HOSSU
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Economic theory. Demography ,HB1-3840 ,Economics as a science ,HB71-74 - Abstract
Biological filtration is the keystone of any recirculating aquaculture system (RAS). Biological treatment process is considered the most economically feasible approach. Unfortunately, there is no ideal biofilter can be used for all different purposes. Understanding the nitrification capacity of different biological filters under actual production conditions will help the recirculating system designers in proper selection of the economically biological filters for the large scale commercial production use. In this review, we shed light on the performance, pros and cons of some of the most commonly used biofiltration systems.
- Published
- 2017
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43. Developing an aggregate metric to measure and benchmarking energy performance
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Kamal JEMMAD, Abdelhamid HMIDAT, and Abdallah SAAD
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Engineering (General). Civil engineering (General) ,TA1-2040 ,Social sciences (General) ,H1-99 - Abstract
As key elements of energy planning, ISO 50001 recommended inter alia identifying appropriate indicators to monitor and measure energy performance. Benchmarking can be a helpful tool to establish energy efficiency or performance indicators. While we agree that is hard to get an absolutely universal indicator aggregating several physical indicators defined in differing units; it is however possible to expand the area of cases covered or improve its characteristics such as accuracy, representativeness and simplicity. In this paper, we developed an aggregated dimensionless “Indicator for Energy Benchmarking” (IEB) to enhance the range of models of indicators dedicated to the engineering field. The systems targeted are low and middle level systems of the energy indicators pyramid. We built the proposed indicator based on specific characteristics: process decomposition-oriented, increasing when energy consumption decreases, dimensionless, with limited threshold value to 1. Consequently, the indicator provides many advantages in comparison to simple metrics and complex indicators such as: direct detection of energy use failure processes, creating interdependence between benchmarked systems scores, no need for data history to start benchmarking of a multisystem. IEB can be implemented as an integral part of many energy management or energy efficiency standards, methodologies or tools such as EN 16231:2012 and ISO 50001:2018. In last section, we calculate the indicator for 2 central sterile service departments of 2 university hospitals in Morocco to show its potential and operating mode.
- Published
- 2019
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44. An Experimental Investigation of the Convective Heat Transfer on a Small Helicopter Rotor with Anti-Icing and De-Icing Test Setups
- Author
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Abdallah Samad, Eric Villeneuve, Caroline Blackburn, François Morency, and Christophe Volat
- Subjects
convective heat transfer ,icing/de-icing ,rotorcraft ,wind tunnel ,experiments ,Motor vehicles. Aeronautics. Astronautics ,TL1-4050 - Abstract
Successful icing/de-icing simulations for rotorcraft require a good prediction of the convective heat transfer on the blade’s surface. Rotorcraft icing is an unwanted phenomenon that is known to cause flight cancelations, loss of rotor performance and severe vibrations that may have disastrous and deadly consequences. Following a series of experiments carried out at the Anti-icing Materials International Laboratory (AMIL), this paper provides heat transfer measurements on heated rotor blades, under both the anti-icing and de-icing modes in terms of the Nusselt Number (Nu). The objective is to develop correlations for the Nu in the presence of (1) an ice layer on the blades (NuIce) and (2) liquid water content (LWC) in the freestream with no ice (NuWet). For the sake of comparison, the NuWet and the NuIce are compared to heat transfer values in dry runs (NuDry). Measurements are reported on the nose of the blade-leading edge, for three rotor speeds (Ω) = 500, 900 and 1000 RPM; a pitch angle (θ) = 6°; and three different radial positions (r/R), r/R = 0.6, 0.75 and 0.95. The de-icing tests are performed twice, once for a glaze ice accretion and another time for rime ice. Results indicate that the NuDry and the NuWet directly increased with V∝, r/R or Ω, mainly due to an increase in the Reynolds number (Re). Measurements indicate that the NuWet to NuDry ratio was always larger than 1 as a direct result of the water spray addition. NuIce behavior was different and was largely affected by the ice thickness (tice) on the blade. However, the ice acted as insulation on the blade surface and the NuIce to NuDry ratio was always less than 1, thus minimizing the effect of convection. Four correlations are then proposed for the NuDry, the NuWet and the NuIce, with an average error between 3.61% and 12.41%. The NuDry correlation satisfies what is expected from heat transfer near the leading edge of an airfoil, where the NuDry correlates well with Re0.52.
- Published
- 2021
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45. A Numerical and Experimental Investigation of the Convective Heat Transfer on a Small Helicopter Rotor Test Setup
- Author
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Abdallah Samad, Eric Villeneuve, François Morency, and Christophe Volat
- Subjects
convective heat transfer ,icing/de-icing ,rotorcraft ,CFD ,experiments ,Motor vehicles. Aeronautics. Astronautics ,TL1-4050 - Abstract
In-flight icing affects helicopter performance, limits its operations, and reduces safety. The convective heat transfer is an important parameter in numerical icing simulations and state-of-the-art icing/de-icing codes utilize important computing resources when calculating it. The BEMT–RHT and UVLM–RHT offer low- and medium-fidelity approaches to estimate the rotor heat transfer (RHT). They are based on a coupling between Blade element momentum theory (BEMT) or unsteady vortex lattice method (UVLM), and a CFD-determined heat transfer correlation. The latter relates the Frossling number (Fr) to the Reynolds number (Re) and effective angle of attack (αEff). In a series of experiments carried out at the Anti-icing Materials International Laboratory (AMIL), this paper serves as a proof of concept of the proposed correlations. The objective is to propose correlations for the experimentally measured rotor heat transfer data. Specifically, the Frx is correlated with the Re and αEff in a similar form as the proposed CFD-based correlations. A fixed-wing setup is first used as a preliminary step to verify the heat transfer measurements of the icing wind tunnel (IWT). Tests are conducted at α = 0°, for a range of 4.76 × 105 ≤ Re ≤ 1.36 × 106 and at 10 non-dimensional surface wrap locations − 0.62 ≤ (S/c) ≤ + 0.87. Later, a rotor setup is used to build the novel heat transfer correlation, tests are conducted at two pitch angles ((θ) = 0° and 6°) for a range of rotor speeds (500 RPM ≤ (Ω) ≤ 1500 RPM), three different radial positions ((r/R) = 0.6, 0.75 and 0.95), and 0 ≤ S/c ≤ + 0.58. Results indicate that the fixed-wing Frx at the stagnation point was in the range of literature experimental data, and within 8% of fully turbulent CFD simulations. The FrAvg also agrees with CFD predictions, with an average discrepancy of 1.4%. For the rotor, the Ω caused a similar increase of Frx for the tests at θ = 0° and those at θ = 6°. Moreover, the Frx behavior changed significantly with r/R, suggesting the αEff had a significant effect on the Frx. Finally, the rotor data are first correlated with Rem (at each S/c) for θ = 0° to establish the correlation parameters, and a term for the αEff is then added to also account for the tests at θ = 6°. The correlations fit the data with an error between 2.1% and 14%, thus justifying the use of a coupled approach for the BEMT–RHT and UVLM–RHT.
- Published
- 2021
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46. Study of Geometric Elements for the Proposed Protecting Dam Reservoir in Al-Fat'ha Area, Iraq
- Author
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Abdallah Sabbar S., Ali Bahaa Al-Din R., and Ahmed Muhana M.
- Subjects
geometric elements ,al-fat'ha dam ,makhul dam ,protect dam ,dam collapse ,Environmental sciences ,GE1-350 - Abstract
Partially constructed Makhul dam may collapse after the operation due to the geological and geotechnical background of the foundations zone, and the presence of gypsum layers in this zone, Then the construction of Al-Fat'ha protection dam is one of the proposed solutions. The present study used the geometric analysis method to investigate the ability of Al-Fat'ha planned protecting dam to reduce the disasters of Makhul dam break. The new methodology used to derive the geometric elements of the two dams, and analyze the relations between these elements, and then exam the behavior of Al-Fat'ha proposed dam with and without the studied collapse scenarios. Fourteen collapse scenarios suggested for Makhul dam, from the level 140 m above sea level (a.s.l), to the maximum possible flood level 152 m (a.s.l). A mathematical model was derived to predict the level achieved as a response of cumulative storage in the protecting dam reservoir when the collapse of the Makhul dam occurred. The maximum level in the protecting dam reservoir to face the worst collapse scenario is 147 m (a.s.l), when the corresponding accumulated storage in the reservoir is 3414305769 m3. The results of the geometric analysis indicate that the optimum operating level for Al-Fat'ha dam in the operating conditions without Makhul dam collapse is 118.5 m (a.s.l), which corresponds to the capacity (39243587) m3. The total flooded area between the two dams was calculated for each collapse scenario of Makhul dam; it is about 44 km2 for the worst scenario when nine villages on reservoir banks will submerge. Subsequently, the study confirmed the ability of Al-Fat'ha dam reservoir to contain the direct flood wave caused by the collapse of Makhul dam.
- Published
- 2021
- Full Text
- View/download PDF
47. Predicting Rotor Heat Transfer Using the Viscous Blade Element Momentum Theory and Unsteady Vortex Lattice Method
- Author
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Abdallah Samad, Gitsuzo B. S. Tagawa, François Morency, and Christophe Volat
- Subjects
unsteady vortex lattice method ,blade element momentum theory ,convective heat transfer ,icing/de-icing ,rotorcraft ,Motor vehicles. Aeronautics. Astronautics ,TL1-4050 - Abstract
Calculating the unsteady convective heat transfer on helicopter blades is the first step in the prediction of ice accretion and the design of ice-protection systems. Simulations using Computational Fluid Dynamics (CFD) successfully model the complex aerodynamics of rotors as well as the heat transfer on blade surfaces, but for a conceptual design, faster calculation methods may be favorable. In the recent literature, classical methods such as the blade element momentum theory (BEMT) and the unsteady vortex lattice method (UVLM) were used to produce higher fidelity aerodynamic results by coupling them to viscous CFD databases. The novelty of this research originates from the introduction of an added layer of the coupling technique to predict rotor blade heat transfer using the BEMT and UVLM. The new approach implements the viscous coupling of the two methods from one hand and introduces a link to a new airfoil CFD-determined heat transfer correlation. This way, the convective heat transfer on ice-clean rotor blades is estimated while benefiting from the viscous extension of the BEMT and UVLM. The CFD heat transfer prediction is verified using existing correlations for a flat plate test case. Thrust predictions by the implemented UVLM and BEMT agree within 2% and 80% compared to experimental data. Tip vortex locations by the UVLM are predicted within 90% but fail in extreme ground effect. The end results present as an estimate of the heat transfer for a typical lightweight helicopter tail rotor for four test cases in hover, ground effect, axial, and forward flight.
- Published
- 2020
- Full Text
- View/download PDF
48. Hormonal profile in rutting and non-rutting periods in dromedary camel (Camelus dromedarius)
- Author
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Mohamed FARH, Islah LEKTIB, Rita BARGAÂ, Najia EL ABBADI, Fouad RIAD, El Hassane TAHRI, Abdallah SAFWATE, and Mohammed EL KHASMI
- Subjects
General Works - Abstract
The dromedary camel is a seasonally breeding animal. The breeding season (also called “rutting period” or “rut”) of this species coincides with the winter months and is characterized by significant changes in circulating hormonal levels. During the rutting period (winter season), the circulating levels of testosterone, cortisol and thyroid hormones are significantly higher than in the summer (non rutting season), however levels of vitamin D are very low in the winter, compared with those analyzed in non-rutting period (summer season). These changes may modulate the reproduction function and the thermoregulatory adaptation. Concentrations of circulating hormones during the rutting period vary greatly in the literature which could be explained by environmental and experimental conditions. In the camel, understanding the seasonal fluctuations of the hormonal profile of the camels, can contribute to a fundamental knowledge of the reproduction physiology of this species, and will be of great importance to veterinarians in confirming their clinical diagnosis and enhancing the capacities of camel production and reproduction. The mechanisms of TH, glucocorticoids and vitamin D in the modulation of reproductive function and fertility in the dromedary remain to be studied. Keywords: Testosterone, Thyroid hormones, Cortisol, Vitamin D, Season, Camel, Morocco.
- Published
- 2018
49. AGRHYMET: A drought monitoring and capacity building center in the West Africa Region
- Author
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Seydou B. Traore, Abdou Ali, Seydou H. Tinni, Mamadou Samake, Issa Garba, Issoufou Maigari, Agali Alhassane, Abdallah Samba, Maty Ba Diao, Sanoussi Atta, Pape Oumar Dieye, Hassan B. Nacro, and Kouamé G.M. Bouafou
- Subjects
Drought monitoring center ,Environmental monitoring ,Food security early warning ,Human resources development ,Sahel ,West Africa ,Meteorology. Climatology ,QC851-999 - Abstract
The AGRHYMET Regional Center, a specialized institution of the Permanent Interstates Committee for Drought Control in the Sahel (CILSS), was created in 1974 at the aftermaths of the severe droughts that affected this region in the early 1970s. The mission assigned to the Center was to train personnel, provide adequate equipment for the meteorological and hydrological stations networks, and set up regional and national multidisciplinary working groups to monitor the meteorological, hydrological, crops and pastures conditions during the rainy season. As such, it can be considered as the West Africa drought monitoring center, similarly to its younger counterparts in Eastern and Southern Africa. After 40 years of existence, AGRHYMET’s scope of activities expend now beyond the geographical boundaries of CILSS member states, to include the whole West Africa thanks to several initiatives it has been implementing on behalf of the Economic Commission of West African States (ECOWAS) on food security and environmental issues, including climate change. Throughout the years, AGRHYMET developed, in collaboration with international research organizations, models and methodologies based on ground and satellite observations to monitor rainfall, food crop water requirements satisfaction and prospective yields, the progress of vegetation front and its seasonal and interannual variations. It has trained about 1200 new experts in agrometeorology, hydrology, equipment maintenance, and plant protection, and more than 6000 professionals on topics related to food security, climate change, and sustainable natural resources (land and water) management. As of now, AGRHYMET staff is involved in several international initiatives on climate change, food security, and environmental monitoring that allow them keep abreast of the best available technologies and methods, and also contribute to generating knowledge on those issues.
- Published
- 2014
- Full Text
- View/download PDF
50. Warburg′s effect on solid tumors
- Author
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Talal El Imad, Lara El Khoury, and Abdallah Sassine Geara
- Subjects
Medicine - Abstract
Lactic acidosis is the result of imbalance between the systemic formation of lactate and its hepatic metabolism. In cancer patients, lactic acidosis is mainly associated with hematologic malignancies (leukemia and lymphomas) and the mechanism is known as Warburg′s effect. We report a 76-year-old male known to have hypertension and coronary artery disease, who presented with abdominal distension and lactic acidosis. His initial evaluation showed multiple liver masses that were biopsied and the patient was diagnosed with undifferentiated carcinoma of unknown primary, involving the liver. The patient had progression of lactic acidosis leading to his death on day-15. As the lactic acidosis was not in the setting of hypoxia or hemodynamic instability, we made the diagnosis of malignancy-associated type B lactic acidosis, also known as the Warburg′s effect. Warburg′s effect can occur in solid cancer if the tumor involves the liver. It has bad prognostic implications. The use of intravenous bicarbonate as a temporary measure is of controversial benefit, as it can potentially worsen the metabolic acidosis and its use should be limited to patients with very low pH. In cancer patients, the use of lactatebased intravenous fluids can be potentially harmful and can increase the risk of tumor metastasis, at least in animal malignancy models.
- Published
- 2014
- Full Text
- View/download PDF
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