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result(s) for
"Abdou, Abdallah A."
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Effect of canal bed slope on the working efficiency of water energy dissipaters downstream control structures
2026
The design of open irrigation channels typically includes a bed slope to achieve the desired hydraulic performance, governing key parameters such as velocity, water depth, and discharge. Diversion head structures, often constructed across these channels, raise upstream water levels, generating potential energy that converts into high-velocity kinetic energy downstream Previous research has studied the type and configuration of water energy dissipaters, considering most hydraulic parameters affecting their performance, except for canal bed slope. The current work aims to explore the extent to which canal bed slope affects the performance efficiency of water energy dissipaters behind head structures, ensuring their safety. The experiments utilized a tilting flume under controlled conditions at six different bed slopes (0.05% to 0.30%) in addition to a zero bed slope, with five discharge values ranging from 9.76 to 17.14 L/s. Through 150 experimental runs, all hydraulic parameters affecting the performance efficiency of the water energy dissipater (relative energy loss, hydraulic jump, sequent depth ratio, and jump length) are measured and recorded. The results clearly show that increasing the canal bed slope to 0.20% enhances the water energy dissipater’s performance efficiency by 31.9%, reduces the jump length by 20% and lowers the sequent depth ratio (
y
2
y
1
)
by 20%. The recommended relative dissipater location
(
L
b
b
)
of 5.83 is accurate for canals with slopes up to 0.20% but for steeper slopes, this ratio must be checked.
Journal Article
Interactive effects of wing wall configuration and canal inside slope on hydraulic performance of water structures
by
Ashour, Mohamed A.
,
Abu-Zaid, Tarek S.
,
Abueleyon, Haitham M.
in
Aquatic Pollution
,
Canal inside slope
,
Canals
2026
Improving the operational effectiveness of water structures requires effective hydraulic design. Significant changes in water levels, velocity distribution, heading up, and energy loss occur at the entrance zone of these structures because of the interaction between the canal inside slope and upstream wing walls geometry. However, prior research has not adequately assessed the integrated hydraulic effects of these characteristics. This study experimentally examines the interplay between wing wall type and canal inside slope on the hydraulic performance of water structures. A total of 360 laboratory experiments were conducted using four upstream wing wall configurations (box, broken, curved, and splayed) and three canal inside slopes (Z = H:V = 1:1, 3:2, and 2:1), representing common conditions in Egyptian irrigation canals. The findings show that hydraulic behavior is strongly influenced by both parameters. When compared to the box type, the splayed configuration exhibited the lowest energy losses and afflux, with reductions of up to 84.12% and 30.01%, respectively. Furthermore, steeper slopes were linked to higher afflux and energy losses, while the 1:1 canal inside slope continuously exhibited maximum hydraulic efficiency. New empirical relationships were developed to enable the prediction and optimization of irrigation structure performance. The outcomes support sustainable water management by increasing operational dependability, lowering maintenance requirements, and increasing hydraulic efficiency. For both new construction and rehabilitation projects, the study suggests giving priority to splayed wing walls in conjunction with a 1:1 canal inside slope, considering the soil conditions.
Journal Article
The Extent to Which the Available Water Resources in Upper Egypt Can Be Affected by Climate Change
by
Ashour, Mohamed A.
,
Abu-Zaid, Tarek S.
,
Hashem, Radwa H.
in
Arid zones
,
Canals
,
Climate change
2024
Over the past two decades, rapid climate change has severely impacted people’s lives globally, affecting their safety and sustainability. Water, a vital human resource, has been severely affected, with drought and high temperatures leading to desertification, the drying up of rivers and lakes, spontaneous fires in forests, and massive floods and torrents due to melting ice and rising sea and ocean surface water levels. The expected impacts of climate change on the Nile, Egypt’s primary water source, are significant. These impacts can vary across regions, depending on factors like local climate, socio-economic dynamics, topography, and environmental nature. Upper Egypt, characterized by arid and semi-arid regions, faces water scarcity and socio-economic development challenges. Climate change exacerbates these issues, posing significant threats to the region’s ecological sustainability and socio-economic development. Therefore, it is crucial to address these impacts to ensure the Nile’s continued vitality and sustainability. The study aims to analyze the climate change data over the past few decades, analyze its characteristics, and model its effects on Upper Egypt’s water sources. The study expected a big decrease in the water resources of the Nile. While what is currently occurring in terms of fluctuating rainfall rates between scarcity and severity contradicts the results of those studies, that is the best evidence of the need for further research and studies to obtain more reliable and consistent results with the reality that it may help decision-makers to develop scenarios to manage climate change effectively, preventing or reducing negative effects, and finding suitable alternatives. Studies predict a 10% decrease in Nile revenue at Aswan High Dam Lake by 2095, with some predicting a 30% increase. This lack of credibility underscores the need for more comprehensive studies.
Journal Article
Numerical Simulation for the Desired Compatibility between the Inside Slopes of Open Irrigation Canals, and the Used Type of Wing Walls for the Most Efficient Performance of Water Structures
by
Ashour, Mohamed A.
,
Abu-Zaid, Tarek S.
,
Abueleyon, Haitham M.
in
Accuracy
,
Canals
,
canals inside slopes
2024
The design of water structures is crucial for efficient hydraulic performance. Open irrigation canals are designed with specific inside slopes to ensure maximum stability, while the wing walls of water structures constructed across the canal are designed to maximize hydraulic performance. Therefore, ensuring compatibility between the canal inside slopes and the wing wall types used on both the upstream and downstream sides is of great importance for achieving optimum hydraulic performance. However, our literature review indicates that this necessary compatibility between the canal inside slope and the wing wall type has not been adequately researched and studied. This present study aims to numerically investigate the relationship between open canals inside slopes and wing wall types, as well as examine the impact of using different wing wall types with varying canals inside slopes on hydraulic performance efficiency. Four canal inside slope ratios (Z) (H: V = 2:1, 1.5:1, 1:1, and 0.75:1) are simulated using the HEC-RAS program, along with two types of water structure wing walls (box and broken). The HEC-RAS numerical model provides accurate and reliable estimations of the hydraulic characteristics of flowing water through the structure, and the results are verified using previous experimental measurements available in the literature. The variation (ε%) between the measured and computed results is consistent for estimating specific energy, velocity, heading (afflux), and water depths. The simulation results demonstrate that changing the canal inside slope (Z) from 0.75:1 to 2:1 results in a relative increase of approximately 27.84% in heading up and 15.06% in velocity. Additionally, the broken wing wall proves to be more effective than the box type. The study confirms that the optimal configuration for the most efficient performance of water structures involves utilizing broken-type wing walls on the upstream side, along with a 1H:1V canal inside slope. This configuration reduces the relative velocity and relative heading by approximately 12% and 20%, respectively, which is considered highly favorable.
Journal Article
Impact of the Combined Performance of Canal Inside Slope and Wing Wall Geometry on Scour Behavior: Towards Sustainable Water Structure Design
by
Ashour, Mohamed A.
,
Abu-Zaid, Tarek S.
,
Abueleyon, Haitham M.
in
Canals
,
Dimensional analysis
,
Equilibrium
2026
Water structures play a vital role in regulating irrigation water within open-channel networks by controlling discharge, water levels, flow direction, and velocity. Despite their importance, these structures act as hydraulic obstructions that induce flow disturbances, which may reduce hydraulic efficiency and threaten structural integrity. One of the most critical consequences is localized erosion downstream, posing serious risks to structural safety and long-term performance. From a sustainability perspective, maintaining structural stability and hydraulic efficiency is essential to ensure reliable water delivery, minimize maintenance costs, and extend the service life of irrigation structures. Therefore, mitigating such adverse hydraulic effects is a key component of sustainable water resources management. This study aims to investigate the mechanisms responsible for this phenomenon and propose engineering solutions to reduce its impacts. The geometry of upstream wing walls significantly influences flow behavior both through and downstream of the structure. Additionally, irrigation canals are constructed with varying side slopes depending on soil conditions, which further affect flow characteristics. However, the combined effect of different upstream wing wall configurations and canal inside slopes has not been sufficiently addressed. Accordingly, this research evaluates their integrated impact to support the development of more efficient, resilient, and sustainable irrigation structures. A total of 435 laboratory experiments were conducted using a physical model under varying discharge conditions. Common canal inside slopes were tested with four widely used wing wall types. Scour hole geometry, including depth, length, and shape, was measured and analyzed. Results indicate that the splayed wing wall configuration outperforms the box type, reducing maximum scour depth and length by approximately 22.74% and 23.61%, respectively, when combined with a 1:1 canal inside slope. Additionally, new dimensionless empirical equations were developed to predict downstream scour behavior, providing practical tools for selecting optimal wing wall configurations under different canal conditions.
Journal Article
Genetic characterization of upper respiratory tract virome from nonvaccinated Egyptian cow-calf operations
by
El Damaty, Hend M.
,
Abdallah, Fatma
,
Elsohaby, Ibrahim
in
Adenoviruses
,
Animals
,
Biology and Life Sciences
2022
Bovine respiratory disease (BRD) is the costliest complex disease affecting the cattle industry worldwide, with significant economic losses. BRD pathogenesis involves several interactions between microorganisms, such as bacteria and viruses, and management factors. The present study aimed to characterize the nasal virome from 43 pooled nasal swab samples collected from Egyptian nonvaccinated cow-calf operations with acute BRD from January to February 2020 using metagenomic sequencing. Bovine herpesvirus-1 (BHV-1), first detection of bovine herpesvirus-5 (BHV-5), and first detection of bovine parvovirus-3 (BPV-3) were the most commonly identified in Egyptian cattle. Moreover, phylogenetic analysis of glycoprotein B revealed that the BHV-1 isolate is closely related to the Cooper reference strain (genotype 1.1), whereas the BHV-5 isolate is closely related to the reference virus GenBank NP_954920.1. In addition, the whole-genome sequence of BPV-3 showed 93.02% nucleotide identity with the reference virus GenBank AF406967.1. In this study, several DNA viruses, such as BHV-1 and first detection BHV-5, and BPV-3, were detected and may have an association with the BRD in Egyptian cattle. Therefore, further research, including investigating more samples from different locations to determine the prevalence of detected viruses and their contributions to BRD in cattle in Egypt, is needed.
Journal Article
Mycetoma epidemiology, diagnosis management, and outcome in three hospital centres in Senegal from 2008 to 2018
2020
Mycetoma is a neglected tropical disease caused by various actinomycetes or fungi. The disease is characterized by the formation of tumor like-swellings and grains. Senegal is an endemic country where mycetoma cases are under-or misdiagnosed due to the lack of capacities and knowledge among health workers and the community; and where the management of eumycetoma, burdened by a high amputation rate, is currently inadequate. This study aimed to update data on the epidemiology of mycetoma cases diagnosed in three hospital centres in Senegal over a 10 years-period. A total of 193 patients, diagnosed from 2008 to 2018, were included in the study. The most frequent presentation was eumycetoma (47.2%); followed by actinomycetoma (36.8%); it remained undetermined in 16.1% of the patients. The mean age was 38.3 years (68.4% of the patients were between 15 and 45 years-old); the male: female ratio was a 2.94; and most were farmers. One hundred fifty-six (80.8%) patients had used phytotherapy before attending the hospital. Mycetoma was mainly located to the lower limbs (91.2%). Grains were observed in 85% of the patients; including white (25.6%) and yellow (4.3%) grains. The etiological diagnosis was complex, resulting in negative direct microscopy, culture and/or histopathology findings, which explains that 16.1% remained uncharacterized. In most of cases, actinomycetoma were treated with a combination of cotrimoxazole, amoxicillin/clavulanic acid, and streptomycin; whereas eumycetoma cases were treated with terbinafine. The surgery was done in 100 (51.8%) of the patients including 9 in actinomycetoma, 78 in eumycetoma and 13 in undetermined form. The high number of uncharacterized mycetoma in this study, the delay in attending a qualified health-care facility, and the lack of available adequate antifungal drug, point out the need to strengthen mycetoma management capacities in Senegal.
Journal Article
BTN3A: A Promising Immune Checkpoint for Cancer Prognosis and Treatment
by
Kone, Abdou-samad
,
Ait Ssi, Saadia
,
Badou, Abdallah
in
Biomarkers
,
Brain cancer
,
Breast cancer
2022
Butyrophilin-3A (BTN3A) subfamily members are a group of immunoglobulins present on the surface of different cell types, including innate and cancer cells. Due to their high similarity with the B7 family members, different studies have been conducted and revealed the involvement of BTN3A molecules in modulating T cell activity within the tumor microenvironment (TME). However, a great part of this research focused on γδ T cells and how BTN3A contributes to their functions. In this review, we will depict the roles and various aspects of BTN3A molecules in distinct tumor microenvironments and review how BTN3A receptors modulate diverse immune effector functions including those of CD4+ (Th1), cytotoxic CD8+ T cells, and NK cells. We will also highlight the potential of BTN3A molecules as therapeutic targets for effective immunotherapy and successful cancer control, which could represent a bright future for patient treatment.
Journal Article
Decoding the secret of extracellular vesicles in the immune tumor microenvironment of the glioblastoma: on the border of kingdoms
2024
Over the last decades, extracellular vesicles (EVs) have become increasingly popular for their roles in various pathologies, including cancer and neurological and immunological disorders. EVs have been considered for a long time as a means for normal cells to get rid of molecules it no longer needs. It is now well established that EVs play their biological roles also following uptake or by the interaction of EV surface proteins with cellular receptors and membranes. In this review, we summarize the current status of EV production and secretion in glioblastoma, the most aggressive type of glioma associated with high mortality. The main purpose is to shed light on the EVs as a universal mediator of interkingdom and intrakingdom communication in the context of tumor microenvironment heterogeneity. We focus on the immunomodulatory EV functions in glioblastoma-immune cross-talk to enhance immune escape and reprogram tumor-infiltrating immune cells. We critically examine the evidence that GBM-, immune cell-, and microbiome-derived EVs impact local tumor microenvironment and host immune responses, and can enter the circulatory system to disseminate and drive premetastatic niche formation in distant organs. Taking into account the current state of the art in intratumoral microbiome studies, we discuss the emerging role of bacterial EV in glioblastoma and its response to current and future therapies including immunotherapies.
Journal Article
Exopolysaccharide produced by Lactiplantibacillus plantarum RO30 isolated from Romi cheese: characterization, antioxidant and burn healing activity
by
Amer, Shaimaa K
,
Elmansy, Eman A
,
Asker, Mohsen S
in
Animal models
,
Antimicrobial agents
,
Antioxidants
2022
Microbial exopolysaccharides (EPSs) extracted from lactic acid bacteria (LAB) are generally recognized as safe. They have earned popularity in recent years because of their exceptional biological features. Therefore, the present study main focus was to study EPS-production from probiotic LAB and to investigate their antioxidant and burn wound healing efficacy. Seventeen LAB were isolated from different food samples. All of them showed EPS-producing abilities ranging from 1.75 ± 0.05 to 4.32 ± 0.12 g/l. RO30 isolate (from Romi cheese) was chosen, due to its ability to produce the highest EPS yield (4.23 ± 0.12 g/l). The 16S rDNA sequencing showed it belonged to the Lactiplantibacillus plantarum group and was further identified as L. plantarum RO30 with accession number OL757866. It displayed well in vitro probiotic properties. REPS was extracted and characterized. The existence of COO−, OH and amide groups corresponding to typical EPSs was confirmed via FTIR. It was constituted of glucuronic acid, mannose, glucose, and arabinose in a molar ratio of 2.2:0.1:0.5:0.1, respectively. The average molecular weight was 4.96 × 104 g/mol. In vitro antioxidant assays showed that the REPS possesses a DPPH radical scavenging ability of 43.60% at 5 mg/ml, reducing power of 1.108 at 10 mg/ml, and iron chelation activity of 72.49% and 89.78% at 5 mg/ml and 10 mg/ml, respectively. The healing efficacy of REPS on burn wound models in albino Wistar rats showed that REPS at 0.5% (w/w) concentration stimulated the process of healing in burn areas. The results suggested that REPS might be useful as a burn wound healing agent.
Journal Article