Landmark University

This study investigated the optimization and effectiveness of corrosion control of Chromolaena odorata leaves extract (COLE) on mild steel in H3PO4. Box–Behnken design was used in this study to determine the influence of variables: temperature (30–60 °C), inhibitor concentration (0.2–0.8 g/l), and duration of immersion (3–12 days) on corrosion rate. The extract was subjected to phytochemical analysis to determine the quantitative and qualitative quantities of bioactive constituents in COLE. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) were used to characterize the samples. The result of phytochemical analysis showed the presence of bioactive constituents that extract makes extracts a good inhibitor. The optimal process conditions observed were as follows: time: 7.5 days, temperature: 45 °C, and inhibition concentration: 0.5 g/l with corrosion rate of 0.0002650 g/mm²days. The SEM and FT-IR result from the validated experiment revealed that compared to mild steel which corrodes at the slowest rate, more passive films were seen due to absorption. The inhibitive potential of Chromolaena odorata leaves extract is a good corrosion inhibitor in the acidic environment.

Alkaloids are a complex class of biologically active compounds with a broad spectrum of health-related applications. Particularly the alkaloids of indole, steroidal, terpenoids, isoquinoline, and bisbenzylisoquinoline have been extensively investigated. Ultimately, substantial advancement has been highlighted in the investigation of chemical constituents and the therapeutic benefits of plant alkaloids, particularly during the last ten years. A total of 386 alkaloids have been isolated from over 40 families, including Apocynaceae, Annonaceae, Rubiaceae, Menispermaceae, Ranunculaceae, Buxaceae, Papaveraceae, Magnoliaceae, Rutaceae and Phyllanthaceae. This paper will investigate several alkaloids that have been isolated from botanical medicines as well as offer an in-depth analysis of their cytotoxic properties.

In the era of computational advancements, harnessing computer algorithms for approximating solutions to differential equations has become indispensable for its unparalleled productivity. The numerical approximation of partial differential equation (PDE) models holds crucial significance in modelling physical systems, driving the necessity for robust methodologies. In this article, we introduce the Implicit Six-Point Block Scheme (ISBS), employing a collocation approach for second-order numerical approximations of ordinary differential equations (ODEs) derived from one or two-dimensional physical systems. The methodology involves transforming the governing PDEs into a fully-fledged system of algebraic ordinary differential equations by employing ISBS to replace spatial derivatives while utilizing a central difference scheme for temporal or y-derivatives. In this report, the convergence properties of ISBS, aligning with the principles of multi-step methods, are rigorously analyzed. The numerical results obtained through ISBS demonstrate excellent agreement with theoretical solutions. Additionally, we compute absolute errors across various problem instances, showcasing the robustness and efficacy of ISBS in practical applications. Furthermore, we present a comprehensive comparative analysis with existing methodologies from recent literature, highlighting the superior performance of ISBS. Our findings are substantiated through illustrative tables and figures, underscoring the transformative potential of ISBS in advancing the numerical approximation of two-dimensional PDEs in physical systems.

Integrating waste materials in the highway sector, especially in asphaltic concrete mixture offers ecological and economic benefits. This study examines the effects of using corncob ash (CCA) as a replacement for the traditional stone dust filler in 5%, 10%, 15%, 20%, and 25%. Volumetric parameters including flow test, bulk density, air void, stability, and voids in mineral for obtained mix asphalt were determined. The optimum bitumen content (OBC) was determined using six replacement rates of 5.0 to 7.5% at intervals of 0.5% by weight. In addition, it was observed that 15% CCA filler replacement produced the best results for OBC at 6.3%, maximum stability at 14.4 KN, flow at 3.8 mm, void filled with bitumen (VFB) at 84.9%, bulk density at 2.55 g/cm3, air void at 4.3%, and finally marshall quotient value at 3.8 KN/mm, which satisfied all requirements of the standard specification for medium traffic roads in asphalt mixture. The study’s results also demonstrated that some of the stone dust fillers in hot mix asphalt may be effectively replaced by agricultural waste materials, potentially enabling the reuse of agricultural waste, optimizing construction costs, and reducing nuisance waste.

This study addresses the need for a more environmentally friendly and sustainable alternative to hexane, the conventional solvent for oil extraction. Hexane, while efficient in dissolving oil, poses neurotoxicity risks and stems from nonrenewable sources. In contrast, ethanol, produced via biotechnological methods, offers a promising alternative due to its minimal environmental impact, cost-effectiveness, and safety profile. The objective of this work is to compare the performance of hexane and ethanol in the extraction of soybean oil, employing simulation techniques rather than traditional laboratory experiments. The research develops a mathematical model for a countercurrent multistage solid–liquid extraction process, specifically tailored for soybean oil extraction, and simulates the process using MATLAB/SIMULINK. The results reveal that hexane exhibits a higher initial extraction rate, especially over a 90-min simulation period, though ethanol demonstrates comparable efficiency. Moreover, ethanol consistently showcases higher extraction efficiency relative to hexane when considering solvent-to-solid mass ratios. In conclusion, both hexane and ethanol extraction prove practical with ethanol holding advantages in terms of safety and extraction efficiency. These simulation findings serve as a valuable foundation for subsequent laboratory experiments which can contribute to the validation and refinement of the simulation model.

Aluminum-iron activated with ore tailing alloy was developed as an anode for the protection of steel in a seawater environment using an impressed current cathodic protection mechanism. The materials used in this research were aluminum, iron ore tailings and low-carbon steel. The anode was produced via the sand-casting method by the addition of varying weight fractions of iron ore tailings (5–25%). The resulting anodes were characterized; the microstructure of the anodes was observed by scanning electron microscopy/energy dispersive spectroscopy, and X-ray diffraction was used to identify the phases present. The corrosion behavior of the anodes was determined in seawater with a salinity of 2.1% using a potentiostat. The micrograph results showed that some anodes had large grains, small grains and a mixture of unevenly distributed grains throughout the material. The energy dispersive spectroscopy spectrogram showed aluminum, oxygen and zinc to be the most prominent elements in the anodes. In addition, inclusions and several intermetallics were observed. Sample D (85 Al% + 15 IOT%) has a corrosion potential of -405.197 mV (silver/silver chloride) compared to steel, which has a corrosion potential of -637.653 mV (silver/silver chloride). Sample D has more positive potentials than steel, which means that sample D is the most suitable anode for protecting steel via impressed current system cathodic protection.

Corrosion is a major challenge faced in industries, which has to be addressed by using inhibitors. The aim of this study was to investigate ESE as I of MS in a 30 wt% NaCl solution. ESE was subjected to Pc analysis, to identify the presence of active ingredients that would create a good CI. CI of ESE at different C was investigated using WL, PDP, SEM, FTIR and EDXS techniques, to characterize MS samples. The best process level from the experimental design was observed at T of 24.4 ºC, IT of 6 days and ESE C of 0.4 g/L, with IE (%) of 95.5 %. The presence of metabolites in ESE was confirmed by Pc analysis, which suggested the extract was a good I. Results from PDP and WL techniques were in good agreement. SEM, FTIR and EDS data revealed that the optimal process level produced more protective film on the MS surface. It was concluded that ESE acted as a good and environmentally friendly I.

Background: Malaria is an infectious oxidative disease, which has continued to cause inconceivable loss of lives every year, almost unabatedly. Currently, it has become more difficult to treat the disease due the emergence and spread of resistance to recommended antimalarial drugs including ACTs, necessitating an urgent search for antimalarial compounds with unique modes of action. Here, we investigated the antimalarial activity, antioxidant and antiinflammatory capacity of Enantia chlorantha aqueous stem bark extract (EcASBE) in vivo. Methods: The extract was screened for selected phytoconstituents including alkaloids and flavonoids. We evaluated the antimalarial activity of EcASBE against Plasmodium berghei NK65 infection in mice, using curative, prophylactic, and suppressive antimalarial test models, respectively. In addition, the antioxidant and antiinflammatory activities of the extract were assessed. Results: The EcASBE significantly (p < 0.05) inhibited parasitaemia dose-dependently, with the highest inhibition (80.4%) and prolonged survival (MST=20) observed in the curative test. Our findings reveal significant (p < 0.05) improvement of serum ALT, AST, ALP, GGT, and levels of TNF-α, creatinine and urea following extract administration. Furthermore, the extract led to a significant (p < 0.05) rise in the levels of CAT, SOD, GPx, and GSH, with a concomitant reduction in NO and MDA levels. Conclusion: The antimalarial, antioxidative, antiperoxidative, and inflammatory-inhibiting properties of the plant in infected mice demonstrate its great value for therapeutic intervention, and substantiate its use in traditional medicine for malaria treatment. Hence, further investigation to identify the repertoire of the active antimalarial components is warranted.

The study presents the Half Max Insertion Heuristic (HMIH) as a novel approach to solving the Travelling Salesman Problem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) and Nearest Neighbour Heuristic (NNH). The paper discusses the limitations of current construction tour heuristics, focusing particularly on the significant margin of error in FIH. It then proposes HMIH as an alternative that minimizes the increase in tour distance and includes more nodes. HMIH improves tour quality by starting with an initial tour consisting of a ‘minimum’ polygon and iteratively adding nodes using our novel Half Max routine. The paper thoroughly examines and compares HMIH with FIH and NNH via rigorous testing on standard TSP benchmarks. The results indicate that HMIH consistently delivers superior performance, particularly with respect to tour cost and computational efficiency. HMIH's tours were sometimes 16% shorter than those generated by FIH and NNH, showcasing its potential and value as a novel benchmark for TSP solutions. The study used statistical methods, including Friedman's Non-parametric Test, to validate the performance of HMIH over FIH and NNH. This guarantees that the identified advantages are statistically significant and consistent in various situations. This comprehensive analysis emphasizes the reliability and efficiency of the heuristic, making a compelling case for its use in solving TSP issues. The research shows that, in general, HMIH fared better than FIH in all cases studied, except for a few instances (pr439, eil51, and eil101) where FIH either performed equally or slightly better than HMIH. HMIH's efficiency is shown by its improvements in error percentage (δ) and goodness values (g) compared to FIH and NNH. In the att48 instance, HMIH had an error rate of 6.3%, whereas FIH had 14.6% and NNH had 20.9%, indicating that HMIH was closer to the optimal solution. HMIH consistently showed superior performance across many benchmarks, with lower percentage error and higher goodness values, suggesting a closer match to the optimal tour costs. This study substantially contributes to combinatorial optimization by enhancing current insertion algorithms and presenting a more efficient solution for the Travelling Salesman Problem. It also creates new possibilities for progress in heuristic design and optimization methodologies.

The genus Landolphia (P. Beauv.) belongs to the Apocynaceae family with over 65 species distributed all over the tropical regions. This genus has a considerable number of documented medicinal, industrial, and ecologically beneficial effects. Therefore, this review is tailored towards the appraisal of the traditional significance, phytochemistry, and pharmacological activities of the genus Landolphia. This will help researchers understand future research trends by bridging the gaps between documented literature and contemporary uses. Relevant information was obtained from selection of scientific databases such as Web of Science, PubMed, Scopus, Google Scholar, ScienceDirect and Wiley. From documented literature, different parts of Landolphia have been used to improve fertility, lessen menstrual pain, boost sex libido, cure malaria and typhoid. Several classes of bioactive constituents such as terpenoids, phenolics, flavonoids, steroids, fatty acids, saponins, phytosterol and phenylpropanoid, volatile compounds, lignans and coumarins have been isolated from this genus. These secondary metabolites could be responsible for the reported antimicrobial, antimalarial, aphrodisiac, antioxidant, anti-inflammatory, antidiabetic and anticancer activities exhibited by this genus. The leaves, flower, bark and root of this genus have a wide range of essential nutrients and antinutrients which are essential for normal growth and development in living organisms. Despite all findings indicating the economical, industrial and pharmacological activities of Landolphia species, secondary metabolites and pharmacological potency of Landolphia of this genus are not adequately documented. Therefore, bioassay-guided isolation on the Landolphia extracts with proven biological activities should be prioritised in order to isolate pharmacophores with unique structural frameworks.

Human infertility can arise from various factors including oxidative stress and endocrine disruptors. This study evaluated the protective effects of Allium cepa-fortified feed on testicular function alterations caused by oxidative damage by KBrO3. HPLC-characterized compounds of Allium cepa were docked against androgen receptor protein (2PIP). Thirty male Wistar rats with an average weight of 200 ± 0.5 g were randomly grouped into six: positive control which received KBrO3 and regular rat chow, negative control was fed only regular chow, and experimental groups received KBrO3 along with 10%, 20%, and 30% of Allium cepa-fortified chow, respectively. The animals were euthanized after 14 days, and the testes were extracted for biochemical assays. There was a significant decrease (P ≤ 0.05) in organ-body weight and protein concentration in the positive control compared to treatment groups and negative control. Additionally, there was a significant increase (P ≤ 0.05) in SOD and ALP activity in the positive control group compared with the negative control and treatment groups. The concentration of MDA significantly decreased (P ≤ 0.05) in the treatment groups and the negative control compared with that in the positive control. Testicular germ cells showed reduced proliferation and inadequate differentiation in the positive control group compared with the treatment and negative control groups. Dichlorodiphenyldichloroethylene, testosterone, and quercetin showed the highest binding energies to the androgen receptor protein. The bioactive components of Allium cepa counteract the generation of free radicals caused by KBrO3 and obstruct the access of endocrine disruptors to endocrine receptors, thereby mitigating oxidative damage.

Waste management and recycling have led to numerous studies on particleboard production. This study attempted to use milled corncob (MCC) and waste ceramic tiles (WCTs) to produce particleboard. The MCC (100−70 wt.%) and WCT (0–30 wt.%) were mixed at different ratios, mixed and compressed at a pressure of 0.25 MPa using urea formaldehyde (UF) resin as adhesive. The physicomechanical and thermal properties of the particleboards produced were investigated. The physical properties (bulk density, water absorption, and thickness swelling) improved with composite particleboard compared to the 100% MCC particleboard. The increase in WCT yielded improved density and lowered the particleboard’s water absorption and thickness swelling. The mechanical tests showed that MOE values were below the recommended standard, which makes them unsuitable for structural use. However, MOR revealed values above the recommended standard. The thermal conductivity of the particleboards was reduced with increased WCT, and the required standard was found to be met. Hence, the particleboards produced are found helpful as thermal wall insulators. Based on the experiments done, sample R7 (70% MCC and 30% WCT) was considered the most preferable since it achieved the most preferable physicomechanical and thermal conductivity performance. The particleboards produced are recommended for wall partitioning and other internal and external purposes.

Agricultural waste materials are potentially dependable and affordable road construction materials that help to develop sustainable pavements, reducing nuisance waste and minimizing construction costs. To determine the suitability of coconut fiber ash (CFA) for use as a filler in asphaltic concrete, this study evaluates the effects of CFA as a filler on the properties of asphaltic concrete. According to ASTM requirements, tests to ascertain the physical and chemical properties of the bitumen, filler, and fine and coarse aggregate were conducted. Marshall specimens were created using varying percentages of 5%, 10%, 15%, 20%, and 25% of coconut fiber ash. To assess each sample’s effectiveness, six replacement rates of 5.0 to 7.5% at an interval of 0.5% by weight were used to determine the optimum bitumen content (OBC), and volumetric characteristics like flow test, stability, density, and air void in mineral aggregates were studied. It was observed that 15% of CFA filler replacement achieved the best values of OBC at 6.3%, maximum stability at 14.4 KN, flow at 3.8 mm, void filled with bitumen (VFB) at 84.9%, bulk density at 2.55 g/cm3 , air void at 4.3%, and lastly marshal quotient value was 3.8 KN/mm which met all the requirement of the standard specification for medium-traffic roads in asphalt mixture. To ensure the optimum performance of the CFA-modifed asphalt mixtures, a 15% CFA is recommended. Keywords Asphalt · Coconut fiber ash · OBC · Marshall stability · Asphaltic concrete

The present study evaluated the effects of ginger and bitterleaf tea infusions on redox and inflammatory balance in rats. Twenty-four Wistar rats with weights of between 160 and 180 g were assigned into four (4) groups (n = 6). The control group received distilled water, while the remaining groups were administered tea infusions of ginger, bitterleaf, or a combination of both at 5 mg/mL, respectively. Bitterleaf and ginger teas elevated the levels of superoxide dismutase, catalase, glutathione peroxidase, and reduced glutathione in rat plasma and liver, while malondialdehyde levels decreased. Furthermore, ginger tea caused an increase in the expression of nuclear factor erythroid-2-related factor 2 (Nrf-2) and reduced tumor necrosis factor alpha (TNF-α). The GC-MS analysis of the teas identified 77 chemical compounds, among which gingerol and precocene I were predominant. Collectively, the findings indicate, in particular, that ginger tea may boost antioxidant and anti-inflammatory capacity by increasing Nrf-2 levels.

Understanding the spatial and temporal patterns of drought and their connection with major climate indices is crucial for creating early warning and drought mitigation strategies. This study analyzed hydrological drought variability and its association with global climate indices in the Sahel Region of Nigeria. Before conducting drought analysis, temperature and precipitation data were verified for consistency using three homogeneity tests. The study utilized six synoptic stations across the area to identify drought periods through the Standardized Precipitation Evapotranspiration Index (SPEI). Drought characteristics such as duration, severity, and amplitude were examined using SPEI data. Trend and variability in drought patterns were assessed with Mann–Kendall trend analysis and wavelet analysis, respectively. The relationship between large climate indices and drought was explored using Pearson correlation analysis. Trend analysis indicated an increase in drought occurrences, with significant findings in four stations. Wavelet analysis identified the 2–4 and 4–8 year bands as crucial for understanding SPEI drought patterns. Correlation analysis showed the influence of various climate trends on concurrent climate events, ranking the impact of climate indices on drought as MEI/SOI > NAO > AMO > DMI. Coherence analysis found significant correlations between ENSO and SPEI, and NAO and SPEI, in the 2–7 and > 8-year bands, respectively. Phase differences suggested that severe wet and dry periods align with La Nina and El Nino events, with strong El Nino events and AMO negative phases mainly causing severe droughts in the area.

Introduction The need for money, the pursuit of pleasure, and the liberalized access to gambling have been documented in several pieces of literature as the drivers of gambling. Such drivers are predicated on commercialized gambling, leading to the growth of the gambling industry and constituting a structural influence that normalizes the activity among young people. Methods Through a qualitative inquiry, this study investigates the social agentic factors of individuals who are susceptible to gambling. Fifteen non-gamblers were recruited across three commercial cities in Africa, namely Nairobi, Lagos, and Johannesburg. We first established the gambling susceptibility of the participants: their need for money, their passion for football, ownership of a smartphone, access to the internet, and exposure to football gambling marketing. Results Consequently, we probed for their agency, which is indicative of why they do not gamble, despite being susceptible to engaging in the activity. Four major agentic factors were identified from the participants; knowledge of the industry’s business model, conserving the integrity of football, identity of self, morality and/or religion model. Discussion As such, these factors may be utilized to develop an intervention program for gamblers within the geographical context.

The mitophagy process, a type of macroautophagy, is the targeted removal of mitochondria. It is a type of autophagy exclusive to mitochondria, as the process removes defective mitochondria one by one. Mitophagy serves as an additional level of quality control by using autophagy to remove superfluous mitochondria or mitochondria that are irreparably damaged. During spermatogenesis, mitophagy can influence cell homeostasis and participates in a variety of membrane trafficking activities. Crucially, it has been demonstrated that defective mitophagy can impede spermatogenesis. Despite an increasing amount of evidence suggesting that mitophagy and mitochondrial dynamics preserve the fundamental level of cellular homeostasis, little is known about their role in developmentally controlled metabolic transitions and differentiation. It has been observed that male infertility is a result of mitophagy's impact on sperm motility. Furthermore, certain proteins related to autophagy have been shown to be present in mammalian spermatozoa. The mitochondria are the only organelle in sperm that can produce reactive oxygen species and finally provide energy for sperm movement. Furthermore, studies have shown that inhibited autophagy-infected spermatozoa had reduced motility and increased amounts of phosphorylated PINK1, TOM20, caspase 3/7, and AMPK. Therefore, in terms of reproductive physiology, mitophagy is the removal of mitochondria derived from sperm and the following preservation of mitochondria that are exclusively maternal.

Every new storage tank in the oil sector is required to be calibrated before using them for oil storage and also to be re-calibrated as statutorily required. Depending on the prevailing regulatory guidelines in the country, either a wet or geometrical method of calibration is adopted. This study examines various geometrical methods of tank calibration vis–a–vis their strengths and weaknesses. Tank farm owners (operators) are always faced with the challenge of selecting the best geometrical method of tank calibration while considering some number of factors. To address this aforementioned issue, this study was embarked upon to rank the known four (4) geometrical methods of tank calibration using Fuzzy TOPSIS (F-TOPSIS) approach. Three different experts were drawn from reputable calibration companies to respond to the questionnaire based on the following criteria: Accuracy; Hazard involved; Time consumed; Drudgery involved; and Cost. The interdependencies among the criteria were considered, and a triangular fuzzy set was adopted. The results revealed that the Electro-Optical Distance Ranging (EODR) is the best alternative with a closeness coefficient of 0.974, while the Optical Reference Line Method was ranked least with a closeness coefficient of 0.197. To validate the result of rating by F-TOPSIS, another hybrid MCDM, Fuzzy Analytic Hierarchy Process (FAHP) was used to rank the alternatives, and EODR was also ranked as the best alternative. Sensitivity analysis was carried out for five different scenarios to validate the robustness of the decision-making tool used in this study. All the scenarios considered for the sensitivity analysis ranked EODR and OTM (Optical Triangulation Method) first and second, respectively. So, it can be concluded that EODR is the best geometrical method of tank calibration. Though the cost of using EODR might be higher than other methods, this is being compensated for by higher accuracy, less time with less exposure to hazards. It can also be confirmed that F-TOPSIS is a formidable MCDM tool that finds its usage in every facet of life for a robust decision-making process.