Pub Date : 2025-02-05DOI: 10.1016/j.sciaf.2025.e02581
El Mehdi Karim , Meriem Khedraoui , Abdelkbir Errougui , Yasir S. Raouf , Abdelouahid Samadi , Samir Chtita
The search for innovative therapeutic strategies remains critical in addressing cancer, one of the leading global health challenges. Ribosomal S6 Kinase 2 (RSK2), a serine/threonine kinase, has emerged as a promising target for cancer therapy because it is implicated in oncogenic signaling. Herein, we developed an open-source computational pipeline, identified as DockCADD (available at https://github.com/mehdikariim/DockCADD), which enables the identification of potent RSK2 inhibitors by automated virtual screening, ADME-Tox profiling, and molecular dynamics (MD) simulations. Employing pyran derivatives as the scaffold, top-scoring inhibitors as identified by the pipeline showed scores ranging from -9.46 to -9.89 kcal/mol and binding free energies ranging from -53.731 to -55.193 kcal/mol. Ligands L1, L2 and L3 showed stable binding within the ATP-binding pocket, wherein the compounds undergo slight structural distortions with a favorable van der Waal's interaction. The ligand L3 has exhibited the highest MM-GBSA binding free energy (-55.193 kcal/mol), which so far presents the most promising candidate. These results have pointed out the use of DockCADD as an efficient tool for the fast and low-cost process of drug discovery; L1–L3 should be further validated experimentally for cancer therapy.
{"title":"DockCADD: A streamlined in silico pipeline for the identification of potent ribosomal S6 Kinase 2 (RSK2) inhibitors","authors":"El Mehdi Karim , Meriem Khedraoui , Abdelkbir Errougui , Yasir S. Raouf , Abdelouahid Samadi , Samir Chtita","doi":"10.1016/j.sciaf.2025.e02581","DOIUrl":"10.1016/j.sciaf.2025.e02581","url":null,"abstract":"<div><div>The search for innovative therapeutic strategies remains critical in addressing cancer, one of the leading global health challenges. Ribosomal S6 Kinase 2 (RSK2), a serine/threonine kinase, has emerged as a promising target for cancer therapy because it is implicated in oncogenic signaling. Herein, we developed an open-source computational pipeline, identified as DockCADD (available at <span><span>https://github.com/mehdikariim/DockCADD</span><svg><path></path></svg></span>), which enables the identification of potent RSK2 inhibitors by automated virtual screening, ADME-Tox profiling, and molecular dynamics (MD) simulations. Employing pyran derivatives as the scaffold, top-scoring inhibitors as identified by the pipeline showed scores ranging from -9.46 to -9.89 kcal/mol and binding free energies ranging from -53.731 to -55.193 kcal/mol. Ligands L1, L2 and L3 showed stable binding within the ATP-binding pocket, wherein the compounds undergo slight structural distortions with a favorable van der Waal's interaction. The ligand L3 has exhibited the highest MM-GBSA binding free energy (-55.193 kcal/mol), which so far presents the most promising candidate. These results have pointed out the use of DockCADD as an efficient tool for the fast and low-cost process of drug discovery; L1–L3 should be further validated experimentally for cancer therapy.</div></div>","PeriodicalId":21690,"journal":{"name":"Scientific African","volume":"27 ","pages":"Article e02581"},"PeriodicalIF":2.7,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143376591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01DOI: 10.1016/j.sciaf.2025.e02567
Hend A. Sabry , Sally M. Salaah , Marwa M. El-Naggar , Elham H.A. Ali , Magdy T. Khalil , Amal A.E. Ibrahim , Amr B. Mostafa
The vulnerability of hospital wastewater (HWW) to natural ecosystems makes it a serious threat to health and well-being. Since HWW has a poor biodegradability index, traditional biological treatment approaches are frequently ineffectual in treating it. Thus, the purpose of this study was to evaluate the impact of nanocomposite (NiFe2O4) treatment on HWW toxicity in the freshwater crayfish's muscles and the hepatopancreas (HP). Three groups of crayfish were subjected to study, each containing 20 individuals. Group I served as the control with tap water; Group II was exposed to HWW, and Group III received nano-HWW for 28 consecutive days. The research demonstrated that HWW treated with nanocomposite (NiFe2O4) may decrease the impairment effects of HWW exerted on the HP and muscles. This improvement was attained by reducing the HP and muscles' toxicity through lowering nitric oxide contents, lipid peroxidation, protein carbonyl, and 8‑hydroxy- deoxyguanosine, while decreasing total antioxidant capacities, cytochrome P450, adenosine triphosphate, and calcium. Additionally, ameliorations were detected in the histological structure of the HP and muscles. In conclusion, this study presents an economic nanotechnology procedure for clearing HWW to prevent pollution in the environment. Clearing water from HWW pollutants will protect aquatic animals from degeneration and safeguard the ecosystem.
{"title":"Nanocomposite treatment of hospital wastewater; Prophylaxis toxicity in the freshwater crayfish muscles and hepatopancreas","authors":"Hend A. Sabry , Sally M. Salaah , Marwa M. El-Naggar , Elham H.A. Ali , Magdy T. Khalil , Amal A.E. Ibrahim , Amr B. Mostafa","doi":"10.1016/j.sciaf.2025.e02567","DOIUrl":"10.1016/j.sciaf.2025.e02567","url":null,"abstract":"<div><div>The vulnerability of hospital wastewater (HWW) to natural ecosystems makes it a serious threat to health and well-being. Since HWW has a poor biodegradability index, traditional biological treatment approaches are frequently ineffectual in treating it. Thus, the purpose of this study was to evaluate the impact of nanocomposite (NiFe<sub>2</sub>O<sub>4</sub>) treatment on HWW toxicity in the freshwater crayfish's muscles and the hepatopancreas (HP). Three groups of crayfish were subjected to study, each containing 20 individuals. Group I served as the control with tap water; Group II was exposed to HWW, and Group III received nano-HWW for 28 consecutive days. The research demonstrated that HWW treated with nanocomposite (NiFe<sub>2</sub>O<sub>4</sub>) may decrease the impairment effects of HWW exerted on the HP and muscles. This improvement was attained by reducing the HP and muscles' toxicity through lowering nitric oxide contents, lipid peroxidation, protein carbonyl, and 8‑hydroxy- deoxyguanosine, while decreasing total antioxidant capacities, cytochrome P450, adenosine triphosphate, and calcium. Additionally, ameliorations were detected in the histological structure of the HP and muscles. In conclusion, this study presents an economic nanotechnology procedure for clearing HWW to prevent pollution in the environment. Clearing water from HWW pollutants will protect aquatic animals from degeneration and safeguard the ecosystem.</div></div>","PeriodicalId":21690,"journal":{"name":"Scientific African","volume":"27 ","pages":"Article e02567"},"PeriodicalIF":2.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143368192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01DOI: 10.1016/j.sciaf.2025.e02573
Adama Taonda , Issouf Zerbo , Innocent Charles Emmanuel Traore , Fousseni Folega , Anny Estelle N'Guessan , Justin N'Dja Kassi , Adjima Thiombiano
Quantification of plant biomass and carbon is critical for the savanna species. The lack of accurate biomass tools is a challenge for the savanna species. Information on allometric equations is limited for Detarium microcarpum species. This study aimed to develop an allometric equation for the aboveground biomass of D. microcarpum across the two climatic zones. A total of 60 trees were considered using the destructive method. Three equations were tested with a diameter at the breast (dbh) alone, height (ht) as additional (dbh*ht), and diameter in combination with height (dbh2*ht) as predictors using log-transformed data with a power function. Their performance was assessed with the adjusted R-square (Adj.R2), Akaike Information Criteria (AIC), correction factors (CF), and the Root Mean Square Error (RMSE). The performance of the validated allometric models was compared with the generalized pantropical equation (Chave et al., 2014). The results revealed that the diameter is a good predictor in the Sudano-Sahelian zone and for branches and leaves biomass estimates in the Sudanian zone. The stem requires ht with the dbh (dbh2*ht) in the Sudano-Sahelian zone.
The allometric models established to predict D. microcarpum biomass were
TAGB = e4.4002 (dbh*dbh*h) 0.9456 + e-3.5219 (dbh)2.4007 + e-2.8845(dbh)1.3465 in the Sudanian zone and TAGB = e-4.1053 (dbh)2.4222 + e-5.2567(dbh)2.9539 + e-2.9894(dbh)1.5285 for the Sudano-Sahelian climatic zone. The equations developed in this study are useful tools for assessing the aboveground biomass and the carbon of the savanna multipurpose species.
{"title":"Allometric models for estimating aboveground biomass and carbon stocks of the semi-arid savanna woody species, Detarium microcarpum Guill. et Perr.","authors":"Adama Taonda , Issouf Zerbo , Innocent Charles Emmanuel Traore , Fousseni Folega , Anny Estelle N'Guessan , Justin N'Dja Kassi , Adjima Thiombiano","doi":"10.1016/j.sciaf.2025.e02573","DOIUrl":"10.1016/j.sciaf.2025.e02573","url":null,"abstract":"<div><div>Quantification of plant biomass and carbon is critical for the savanna species. The lack of accurate biomass tools is a challenge for the savanna species. Information on allometric equations is limited for <em>Detarium microcarpum</em> species. This study aimed to develop an allometric equation for the aboveground biomass of <em>D. microcarpum</em> across the two climatic zones. A total of 60 trees were considered using the destructive method. Three equations were tested with a diameter at the breast (dbh) alone, height (ht) as additional (dbh*ht), and diameter in combination with height (dbh<sup>2</sup>*ht) as predictors using log-transformed data with a power function. Their performance was assessed with the adjusted R-square (Adj.R<sup>2</sup>), Akaike Information Criteria (AIC), correction factors (CF), and the Root Mean Square Error (RMSE). The performance of the validated allometric models was compared with the generalized pantropical equation (Chave et al., 2014). The results revealed that the diameter is a good predictor in the Sudano-Sahelian zone and for branches and leaves biomass estimates in the Sudanian zone. The stem requires ht with the dbh (dbh<sup>2</sup>*ht) in the Sudano-Sahelian zone.</div><div>The allometric models established to predict <em>D. microcarpum</em> biomass were</div><div>TAGB = <sup>e4.4002 (dbh*dbh*h) 0.9456</sup> + <em>e</em><sup>-3.5219 (dbh)2.4007</sup> + <em>e</em><sup>-2.8845(dbh)1.3465</sup> in the Sudanian zone and TAGB = <em>e</em><sup>-4.1053 (dbh)2.4222</sup> + <em>e</em><sup>-5.2567(dbh)2.9539</sup> + <em>e</em><sup>-2.9894(dbh)1.5285</sup> for the Sudano-Sahelian climatic zone. The equations developed in this study are useful tools for assessing the aboveground biomass and the carbon of the savanna multipurpose species.</div></div>","PeriodicalId":21690,"journal":{"name":"Scientific African","volume":"27 ","pages":"Article e02573"},"PeriodicalIF":2.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143148806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The COVID-19 pandemic has posed significant challenges to global public health, with varying impacts across different regions. In Africa, the disease’s spread and vaccination efforts have been influenced by multiple factors, including geography, socioeconomic status, demographic characteristics, and healthcare infrastructure. This study aims to investigate the spatial epidemiology of COVID-19 across African countries, with a specific focus on understanding the relationship between the geographic distribution of cases, vaccination coverage, and underlying socioeconomic, demographic, and health-related factors. The study utilizes secondary data from the World Health Organization (WHO) and Our World in Data, covering the period from 2020 to 2022. The study employs advanced spatial econometric models — spatial lag model (SLM), spatial lagged X (SLX), and spatial error model (SEM) — to analyze the role of spatial dependence and the influence of neighboring countries on the transmission and vaccination trends across Africa.
The results reveal significant spatial clustering of COVID-19 cases, with hotspots identified in the Northern and Southern regions of Africa. Specifically, the highest case rates were observed in South Africa, Egypt, and Morocco, while vaccination coverage varied widely, with countries like Seychelles achieving over 70% vaccination coverage, while others like South Sudan showed much lower rates (below 10%) in 2022. The analysis indicates that demographic factors such as the proportion of the population aged 65 and older, and health-related factors such as diabetes prevalence, have a substantial impact on the distribution of cases. Socioeconomic factors, including the human development index (HDI), GDP, and population density, also significantly affect both case rates and vaccination coverage. Furthermore, vaccination uptake in 2021 and 2022 was influenced by varying socioeconomic conditions across countries, with some regions exhibiting lower coverage despite higher availability of vaccines.
This study highlights the importance of considering spatial factors in understanding disease transmission and vaccination efforts in Africa. It provides key insights for policymakers to develop targeted interventions that account for the unique geographic and socioeconomic contexts of African countries. Understanding these spatial dynamics is crucial for strengthening public health strategies and ensuring equitable vaccine distribution across the continent. The findings underscore the need for tailored interventions based on geographic and socio-economic conditions, which could lead to more efficient responses to future health crises.
{"title":"Spatial epidemiology based on the analysis of COVID-19 in Africa","authors":"Joyce Akhalakwa Mukolwe , John Kamwele Mutinda , Amos Kipkorir Langat","doi":"10.1016/j.sciaf.2025.e02557","DOIUrl":"10.1016/j.sciaf.2025.e02557","url":null,"abstract":"<div><div>The COVID-19 pandemic has posed significant challenges to global public health, with varying impacts across different regions. In Africa, the disease’s spread and vaccination efforts have been influenced by multiple factors, including geography, socioeconomic status, demographic characteristics, and healthcare infrastructure. This study aims to investigate the spatial epidemiology of COVID-19 across African countries, with a specific focus on understanding the relationship between the geographic distribution of cases, vaccination coverage, and underlying socioeconomic, demographic, and health-related factors. The study utilizes secondary data from the World Health Organization (WHO) and Our World in Data, covering the period from 2020 to 2022. The study employs advanced spatial econometric models — spatial lag model (SLM), spatial lagged X (SLX), and spatial error model (SEM) — to analyze the role of spatial dependence and the influence of neighboring countries on the transmission and vaccination trends across Africa.</div><div>The results reveal significant spatial clustering of COVID-19 cases, with hotspots identified in the Northern and Southern regions of Africa. Specifically, the highest case rates were observed in South Africa, Egypt, and Morocco, while vaccination coverage varied widely, with countries like Seychelles achieving over 70% vaccination coverage, while others like South Sudan showed much lower rates (below 10%) in 2022. The analysis indicates that demographic factors such as the proportion of the population aged 65 and older, and health-related factors such as diabetes prevalence, have a substantial impact on the distribution of cases. Socioeconomic factors, including the human development index (HDI), GDP, and population density, also significantly affect both case rates and vaccination coverage. Furthermore, vaccination uptake in 2021 and 2022 was influenced by varying socioeconomic conditions across countries, with some regions exhibiting lower coverage despite higher availability of vaccines.</div><div>This study highlights the importance of considering spatial factors in understanding disease transmission and vaccination efforts in Africa. It provides key insights for policymakers to develop targeted interventions that account for the unique geographic and socioeconomic contexts of African countries. Understanding these spatial dynamics is crucial for strengthening public health strategies and ensuring equitable vaccine distribution across the continent. The findings underscore the need for tailored interventions based on geographic and socio-economic conditions, which could lead to more efficient responses to future health crises.</div></div>","PeriodicalId":21690,"journal":{"name":"Scientific African","volume":"27 ","pages":"Article e02557"},"PeriodicalIF":2.7,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Understanding the community's knowledge and reliance on plant based traditional medicine is crucial for creating effective, sustainable conservation strategies to protect and preserve these valuable plant resources. This study aimed to explore traditional medicinal plants and the associated indigenous knowledge in the study area. Ethnobotanical data were collected from January to April 2024 using semistructured interviews and guided field observations. Data on medicinal plants and demography were gathered from 99 respondents, including 83 general informants and 16 key informants. A total of 115 medicinal plant species across 44 families were documented. The Asteraceae family was the most represented (11.3%), and the majority of the collected medicinal plants were herbs (52.2%). Leaves were the most frequently used plant parts (57.4%), and oral administration was the predominant route (74.78%). Ocimum lamiifolium Hochst.,emerged as the most effective medicinal plant for treating severe headaches ("Micho") and received the highest fidelity level (97%). The highest informant consensus factor (ICF) was for gastrointestinal diseases (0.92). Furthermore, Croton macrostachyus ranked first as the most versatile multipurpose plant. These findings highlights the critical role of traditional knowledge in local healthcare systems and the importance of sustainable plant utilization. Respondents unanimously (100% agreement) identified firewood collection, population growth, and lack of awareness and education as major threats to medicinal plants.. This study emphasizes the crucial role of traditional medicinal plants in the healthcare practices of communities and the urgent need for sustainable conservation measures to conserve these invaluable resources and indigenous knowledge for the long-term benefit of both human health and biodiversity conservation.
{"title":"Exploring indigenous wisdom: Ethnobotanical documentation and conservation of medicinal plants in Goba District, Southwest Ethiopia","authors":"Ginjo Gitima , Ashenafi Gebre , Yericho Berhanu , Tamirat Wato","doi":"10.1016/j.sciaf.2025.e02571","DOIUrl":"10.1016/j.sciaf.2025.e02571","url":null,"abstract":"<div><div>Understanding the community's knowledge and reliance on plant based traditional medicine is crucial for creating effective, sustainable conservation strategies to protect and preserve these valuable plant resources. This study aimed to explore traditional medicinal plants and the associated indigenous knowledge in the study area. Ethnobotanical data were collected from January to April 2024 using semistructured interviews and guided field observations. Data on medicinal plants and demography were gathered from 99 respondents, including 83 general informants and 16 key informants. A total of 115 medicinal plant species across 44 families were documented. The Asteraceae family was the most represented (11.3%), and the majority of the collected medicinal plants were herbs (52.2%). Leaves were the most frequently used plant parts (57.4%), and oral administration was the predominant route (74.78%). <em>Ocimum lamiifolium</em> Hochst.,emerged as the most effective medicinal plant for treating severe headaches (\"<em>Micho</em>\") and received the highest fidelity level (97%). The highest informant consensus factor (ICF) was for gastrointestinal diseases (0.92). Furthermore, <em>Croton macrostachyus</em> ranked first as the most versatile multipurpose plant. These findings highlights the critical role of traditional knowledge in local healthcare systems and the importance of sustainable plant utilization. Respondents unanimously (100% agreement) identified firewood collection, population growth, and lack of awareness and education as major threats to medicinal plants.. This study emphasizes the crucial role of traditional medicinal plants in the healthcare practices of communities and the urgent need for sustainable conservation measures to conserve these invaluable resources and indigenous knowledge for the long-term benefit of both human health and biodiversity conservation.</div></div>","PeriodicalId":21690,"journal":{"name":"Scientific African","volume":"27 ","pages":"Article e02571"},"PeriodicalIF":2.7,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143269511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-30DOI: 10.1016/j.sciaf.2025.e02565
Mahmoud A. Ibrahim , Attila Dénes
The ongoing COVID-19 pandemic has spurred an urgent need for advanced modeling approaches to understand the complex dynamics of disease transmission. Our model utilizes a system of differential equations that incorporates the impact of both contagious fear and contagious disbelief surrounding the disease on its transmission dynamics. This study presents a time-periodic compartmental model, integrating insights from recent research on time-varying transmission rates. We define the basic reproduction number (), emphasizing its utility as a threshold parameter for global dynamics and periodic solutions. Numerical simulations validate the theoretical findings and provide a nuanced understanding of disease persistence and extinction. The impact of population disbelief and fear on the risk of COVID-19 is investigated, revealing critical insights for public health interventions. The sensitivity analysis of the basic reproduction number underscores the significance of key parameters in shaping disease dynamics. Our results provide insight into the intricate dynamics of COVID-19 transmission, offering valuable considerations to control the spread of the virus.
{"title":"Time-periodic dynamics in COVID-19 transmission considering the impact of population disbelief and fear","authors":"Mahmoud A. Ibrahim , Attila Dénes","doi":"10.1016/j.sciaf.2025.e02565","DOIUrl":"10.1016/j.sciaf.2025.e02565","url":null,"abstract":"<div><div>The ongoing COVID-19 pandemic has spurred an urgent need for advanced modeling approaches to understand the complex dynamics of disease transmission. Our model utilizes a system of differential equations that incorporates the impact of both contagious fear and contagious disbelief surrounding the disease on its transmission dynamics. This study presents a time-periodic compartmental model, integrating insights from recent research on time-varying transmission rates. We define the basic reproduction number (<span><math><msub><mrow><mi>R</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>), emphasizing its utility as a threshold parameter for global dynamics and periodic solutions. Numerical simulations validate the theoretical findings and provide a nuanced understanding of disease persistence and extinction. The impact of population disbelief and fear on the risk of COVID-19 is investigated, revealing critical insights for public health interventions. The sensitivity analysis of the basic reproduction number underscores the significance of key parameters in shaping disease dynamics. Our results provide insight into the intricate dynamics of COVID-19 transmission, offering valuable considerations to control the spread of the virus.</div></div>","PeriodicalId":21690,"journal":{"name":"Scientific African","volume":"27 ","pages":"Article e02565"},"PeriodicalIF":2.7,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
High-Performance Concretes (HPC) play a crucial role in contemporary construction due to their exceptional strength and durability. However, the necessity for high cement content leads to considerable environmental and economic concerns. Consequently, there is an urgent need to explore more eco-friendly alternatives that can sustain the performance of HPC while meeting technical, economic, ecological, and sustainability requirements. One viable option is natural pozzolan (NP), which is abundantly available in many regions and can serve as a partial replacement for cement. . Algeria, for instance, has abundant and low-cost NP, which can significantly decrease clinker demand and enhance eco-concretes' performance. Our objective is to assess how partially substituting cement with NP with a replacement rate ranging from 0 % to 50 % affects the physical, mechanical behavior, and durability of Eco-HPC made with ternary binders. Experimental results indicate that eco-HPC, which includes up to 20 % NP, shows good performance. After 28 days, it achieves a compressive strength of 63.8 MPa, slightly lower than the control HPC's 68.5 MPa. In addition, its long-term strength development reached 84.4 MPa at 180 days compared to 78.2 MPa for the control HPC. Furthermore, the 20 % pozzolan mix demonstrates 15 % less total shrinkage at 180 days and a 25 % decrease in capillary water absorption when compared to the control mix, while retaining adequate workability. These results support the potential of using ternary binder systems with NP in creating eco-friendly HPC, achieving a good balance between environmental advantages and improved durability.
{"title":"Natural pozzolan as a sustainable cement replacement in high-performance concrete: Effects on mechanical properties, durability, and microstructural development","authors":"Yakoub Derrouiche , Djamel Achoura , Jacqueline Saliba , Franck Cassagnabère","doi":"10.1016/j.sciaf.2025.e02574","DOIUrl":"10.1016/j.sciaf.2025.e02574","url":null,"abstract":"<div><div>High-Performance Concretes (HPC) play a crucial role in contemporary construction due to their exceptional strength and durability. However, the necessity for high cement content leads to considerable environmental and economic concerns. Consequently, there is an urgent need to explore more eco-friendly alternatives that can sustain the performance of HPC while meeting technical, economic, ecological, and sustainability requirements. One viable option is natural pozzolan (NP), which is abundantly available in many regions and can serve as a partial replacement for cement. . Algeria, for instance, has abundant and low-cost NP, which can significantly decrease clinker demand and enhance eco-concretes' performance. Our objective is to assess how partially substituting cement with NP with a replacement rate ranging from 0 % to 50 % affects the physical, mechanical behavior, and durability of Eco-HPC made with ternary binders. Experimental results indicate that eco-HPC, which includes up to 20 % NP, shows good performance. After 28 days, it achieves a compressive strength of 63.8 MPa, slightly lower than the control HPC's 68.5 MPa. In addition, its long-term strength development reached 84.4 MPa at 180 days compared to 78.2 MPa for the control HPC. Furthermore, the 20 % pozzolan mix demonstrates 15 % less total shrinkage at 180 days and a 25 % decrease in capillary water absorption when compared to the control mix, while retaining adequate workability. These results support the potential of using ternary binder systems with NP in creating eco-friendly HPC, achieving a good balance between environmental advantages and improved durability.</div></div>","PeriodicalId":21690,"journal":{"name":"Scientific African","volume":"27 ","pages":"Article e02574"},"PeriodicalIF":2.7,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-30DOI: 10.1016/j.sciaf.2025.e02563
Youness Hakam , Hajar Ahessab , Ahmed Gaga , Mohamed Tabaa , Benachir El Hadadi
This study focuses on the control of an OFF-board electric vehicle (EV) charging station, providing a cost-efficient solution for managing high grid demand periods. By integrating a Kalman filter with Artificial Neural Networks (ANN) for Maximum Power Point Tracking (MPPT), the system optimizes energy capture from photovoltaic (PV) panels, even in severe weather conditions and partial shading. Unlike traditional MPPT methods, which face challenges with multiple peaks in the Power–Voltage (P–V) curve, the hybrid algorithm enhances tracking accuracy, reduces errors, and cuts tracking time by up to 99.93%. This ensures a reliable and sustainable power source for EV charging, reducing grid dependency during peak demand. On the inverter side, an innovative Model Predictive Control (MPC) strategy, using a K+2 step approach, is implemented to efficiently regulate the inverter. The system achieves a Total Harmonic Distortion (THD) of just 0.56%, boosting charging speed while minimizing harmonic distortion costs. Controlled by Texas Instruments’ TMS320F28379D digital signal processor, this system offers stable, low-cost EV charging by prioritizing solar energy use, even under harsh weather conditions, over reliance on grid power.
{"title":"Design and simulation of a 5 KW solar-powered hybrid electric vehicle charging station with a ANN–Kalman filter MPPT and MPC-based inverter control for reduced THD","authors":"Youness Hakam , Hajar Ahessab , Ahmed Gaga , Mohamed Tabaa , Benachir El Hadadi","doi":"10.1016/j.sciaf.2025.e02563","DOIUrl":"10.1016/j.sciaf.2025.e02563","url":null,"abstract":"<div><div>This study focuses on the control of an OFF-board electric vehicle (EV) charging station, providing a cost-efficient solution for managing high grid demand periods. By integrating a Kalman filter with Artificial Neural Networks (ANN) for Maximum Power Point Tracking (MPPT), the system optimizes energy capture from photovoltaic (PV) panels, even in severe weather conditions and partial shading. Unlike traditional MPPT methods, which face challenges with multiple peaks in the Power–Voltage (P–V) curve, the hybrid algorithm enhances tracking accuracy, reduces errors, and cuts tracking time by up to 99.93%. This ensures a reliable and sustainable power source for EV charging, reducing grid dependency during peak demand. On the inverter side, an innovative Model Predictive Control (MPC) strategy, using a K+2 step approach, is implemented to efficiently regulate the inverter. The system achieves a Total Harmonic Distortion (THD) of just 0.56%, boosting charging speed while minimizing harmonic distortion costs. Controlled by Texas Instruments’ TMS320F28379D digital signal processor, this system offers stable, low-cost EV charging by prioritizing solar energy use, even under harsh weather conditions, over reliance on grid power.</div></div>","PeriodicalId":21690,"journal":{"name":"Scientific African","volume":"27 ","pages":"Article e02563"},"PeriodicalIF":2.7,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-28DOI: 10.1016/j.sciaf.2025.e02570
Benjamin K. Kokloku , Johannes A.M. Awudza , Michael B. Mensah , Mizpah A.D. Rockson , Francis Kemausuor
Clay minerals are inexpensive and widely available starting materials for the synthesis of zeolites, such as ZSM-5. In this work, clay samples were collected from Anfoega, Mfensi, Teleku-Bokazo, and Tetebu clay reserves in Ghana and used as sources of silica and alumina for the synthesis of ZSM-5 zeolite. The raw clay samples were cleaned, pulverized, and calcined, followed by acid leaching to increase the Si/Al molar ratio, and finally passed through a hydrothermal zeolitization process. Powder-X-ray Diffraction (p-XRD), X-ray fluorescence (XRF), Fourier Transform Infrared spectroscopy (FTIR), and Thermogravimetric Analysis/Differential Scanning Calorimetry (TGA-DSC) were used to characterize the clay samples. All four clay samples contained kaolinite and quartz in addition to other clay minerals. Notably, the pre-treatment processes were key in acquiring the ZSM-5 product. Our results suggest that the controlling factor in making the clay samples viable for the synthesis of ZSM-5 zeolite is the final SiO2/Al2O3 molar ratio obtained after acid leaching. ZSM-5 zeolite was synthesized from all four clay sources at a crystallization temperature and time of 190 °C and 24 h, respectively, demonstrating the potential of the Ghanaian clays as raw materials for zeolite synthesis.
{"title":"Characterization of Ghanaian clays as raw materials for the synthesis of ZSM-5 zeolite","authors":"Benjamin K. Kokloku , Johannes A.M. Awudza , Michael B. Mensah , Mizpah A.D. Rockson , Francis Kemausuor","doi":"10.1016/j.sciaf.2025.e02570","DOIUrl":"10.1016/j.sciaf.2025.e02570","url":null,"abstract":"<div><div>Clay minerals are inexpensive and widely available starting materials for the synthesis of zeolites, such as ZSM-5. In this work, clay samples were collected from Anfoega, Mfensi, Teleku-Bokazo, and Tetebu clay reserves in Ghana and used as sources of silica and alumina for the synthesis of ZSM-5 zeolite. The raw clay samples were cleaned, pulverized, and calcined, followed by acid leaching to increase the Si/Al molar ratio, and finally passed through a hydrothermal zeolitization process. Powder-X-ray Diffraction (p-XRD), X-ray fluorescence (XRF), Fourier Transform Infrared spectroscopy (FTIR), and Thermogravimetric Analysis/Differential Scanning Calorimetry (TGA-DSC) were used to characterize the clay samples. All four clay samples contained kaolinite and quartz in addition to other clay minerals. Notably, the pre-treatment processes were key in acquiring the ZSM-5 product. Our results suggest that the controlling factor in making the clay samples viable for the synthesis of ZSM-5 zeolite is the final SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> molar ratio obtained after acid leaching. ZSM-5 zeolite was synthesized from all four clay sources at a crystallization temperature and time of 190 °C and 24 h, respectively, demonstrating the potential of the Ghanaian clays as raw materials for zeolite synthesis.</div></div>","PeriodicalId":21690,"journal":{"name":"Scientific African","volume":"27 ","pages":"Article e02570"},"PeriodicalIF":2.7,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143097860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-28DOI: 10.1016/j.sciaf.2025.e02572
Abdulhakeem Olarewaju Sulyman , Olawale Moshood Aliyu , Emmanuel Oladipo Ajani , Yusuf Folohunsho Abdulkareem , Isaac Ade Afe , Fathia Oluwakemi Abdulyakeen , Halimat Yusuf Lukman , Saheed Sabiu , Karishma Singh , Kuben Naidoo
Erectile dysfunction (ED) is a prevalent condition linked to diabetes and cardiovascular diseases, with conventional treatments often associated with adverse effects. Plant-derived products, though less explored, offer potential alternatives. This study evaluated the inhibitory effect of citrulline from Citrullus lanatus on PDE5 activity using experimental and computational methods to explore its therapeutic potential. Citrulline is a precursor to arginine, a substrate for nitric oxide (NO) synthesis, which enhances vasodilation and blood flow. Its therapeutic potential in erectile dysfunction lies in its ability to boost NO production, improving penile blood flow and erection quality. Citrulline was extracted from Citrullus lanatus using an adsorbent-based method, and its inhibitory effect on PDE5 was assessed through enzymatic and kinetic analyses. Molecular docking and dynamics simulations were used to evaluate citrulline's binding interaction and stability with PDE5, validated by the RMSD value obtained following superimposition of citrulline with the native ligand of PDE5 and post-dynamic analyses. Citrulline exhibited a concentration-dependent inhibition of PDE5, with an IC50 value of 366.7 µM. Kinetic analyses further elucidated citrulline's non-competitive inhibition pattern while molecular dynamics analysis afforded assessment of the binding stability of citrulline with PDE5, both providing insights into its mechanism of action. Citrulline-PDE5 complex had a higher negative binding free energy (-45.06 ± 4.69 kcal/mol) relative to the conventional drug (sildenafil) (-13.86±10.23 kcal/mol). The citrulline-PDE5 also had lower root mean square fluctuations (1.11 ± 0.65) than sildenafil-PDE5 (1.25 ± 1.77). The findings suggest that citrulline effectively inhibits PDE5 in a non-competitive manner, with higher binding affinity and greater structural stability than sildenafil, highlighting its potential as a more stable and efficient PDE5 inhibitor. However, limitations include its relatively high IC50 and the need for in vivo validation, necessitating further studies to confirm its clinical viability in the development of potential drugs for the management of ED.
{"title":"Mechanisms of L-citrulline on phosphodiesterase 5 in erectile dysfunction intervention","authors":"Abdulhakeem Olarewaju Sulyman , Olawale Moshood Aliyu , Emmanuel Oladipo Ajani , Yusuf Folohunsho Abdulkareem , Isaac Ade Afe , Fathia Oluwakemi Abdulyakeen , Halimat Yusuf Lukman , Saheed Sabiu , Karishma Singh , Kuben Naidoo","doi":"10.1016/j.sciaf.2025.e02572","DOIUrl":"10.1016/j.sciaf.2025.e02572","url":null,"abstract":"<div><div>Erectile dysfunction (ED) is a prevalent condition linked to diabetes and cardiovascular diseases, with conventional treatments often associated with adverse effects. Plant-derived products, though less explored, offer potential alternatives. This study evaluated the inhibitory effect of citrulline from <em>Citrullus lanatus</em> on PDE5 activity using experimental and computational methods to explore its therapeutic potential. Citrulline is a precursor to arginine, a substrate for nitric oxide (NO) synthesis, which enhances vasodilation and blood flow. Its therapeutic potential in erectile dysfunction lies in its ability to boost NO production, improving penile blood flow and erection quality. Citrulline was extracted from <em>Citrullus lanatus</em> using an adsorbent-based method, and its inhibitory effect on PDE5 was assessed through enzymatic and kinetic analyses. Molecular docking and dynamics simulations were used to evaluate citrulline's binding interaction and stability with PDE5, validated by the RMSD value obtained following superimposition of citrulline with the native ligand of PDE5 and post-dynamic analyses. Citrulline exhibited a concentration-dependent inhibition of PDE5, with an IC<sub>50</sub> value of 366.7 µM. Kinetic analyses further elucidated citrulline's non-competitive inhibition pattern while molecular dynamics analysis afforded assessment of the binding stability of citrulline with PDE5, both providing insights into its mechanism of action. Citrulline-PDE5 complex had a higher negative binding free energy (-45.06 ± 4.69 kcal/mol) relative to the conventional drug (sildenafil) (-13.86±10.23 kcal/mol). The citrulline-PDE5 also had lower root mean square fluctuations (1.11 ± 0.65) than sildenafil-PDE5 (1.25 ± 1.77). The findings suggest that citrulline effectively inhibits PDE5 in a non-competitive manner, with higher binding affinity and greater structural stability than sildenafil, highlighting its potential as a more stable and efficient PDE5 inhibitor. However, limitations include its relatively high IC<sub>50</sub> and the need for <em>in vivo</em> validation, necessitating further studies to confirm its clinical viability in the development of potential drugs for the management of ED.</div></div>","PeriodicalId":21690,"journal":{"name":"Scientific African","volume":"27 ","pages":"Article e02572"},"PeriodicalIF":2.7,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143093563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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