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Feature selection is an active research area in data mining and machine learning, especially with the increase in the amount of numerical data. FS is a search strategy to find the best subset of features among a large number of subsets of features. Thus, FS is applied in most modern applications and in various domains, which requires the search for a powerful FS technique to process and classify high-dimensional data. In this paper, we propose a new technique for dimension reduction in feature selection. This approach is based on a recent metaheuristic called Archimedes’ Optimization Algorithm (AOA) to select an optimal subset of features to improve the classification accuracy. The idea of the AOA is based on the steps of Archimedes' principle in physics. It explains the behavior of the force exerted when an object is partially or fully immersed in a fluid. AOA optimization maintains a balance between exploration and exploitation, keeping a population of solutions and studying a large area to find the best overall solution. In this study, AOA is exploited as a search technique to find an optimal feature subset that reduces the number of features to maximize classification accuracy. The K-nearest neighbor (K-NN) classifier was used to evaluate the classification performance of selected feature subsets. To demonstrate the superiority of the proposed method, 16 benchmark datasets from the UCI repository are used and also compared by well-known and recently introduced meta-heuristics in this context, such as: sine-cosine algorithm (SCA), whale optimization algorithm (WOA), butterfly optimization algorithm (BAO), and butterfly flame optimization algorithm (MFO). The results prove the effectiveness of the proposed algorithm over the other algorithms based on several performance measures used in this paper.

Data clustering is a pivotal aspect of data mining, attracting significant attention in the exploration of cluster analysis through optimization algorithms. However, challenges arise in the application of optimization-based techniques, stemming from the non-linear nature of the objective function and the complexities inherent in the search space. Clustering, serving as an unsupervised data analysis technique, is employed to discern homogeneous groups of objects by evaluating the values of their attributes. To overcome the above-mentioned drawbacks, we have proposed in this article a new metaheuristic based on a mathematical model called Sinh Cosh Optimizer (SCHO). This optimizer is based on the geometric functions Sinh and Cosh and consists of four key stages: the exploitation and exploration phases, the limited search strategy and the implementation of a switching mechanism. To evaluate the effectiveness of the suggested approach, we conduct a comparative analysis against four widely acknowledged metaheuristic methods found in the literature. The assessment is performed using ten standard datasets sourced from the UCI Machine Learning Repository. These artificial intelligence algorithms are renowned for their promising capabilities in addressing machine learning problems, particularly those related to data clustering. Comprehensive computational experiments and result analysis demonstrate that the proposed algorithm consistently outperforms the comparison methods while exhibiting remarkable stability. Specifically, the experimental results show that the algorithm achieves superior F-score performance on 9 out of 10 datasets and outperforms in accuracy on 8 out of 10 datasets.

In this study, we introduce a refined approach to encrypting 32-bit color images, leveraging the potential of four 1D chaotic maps – the Logistic map, Tent map, Chebyshev map, and Sine map. These chaotic maps intricately populate the four matrices within our encryption system, assigning exclusive integers ranging from 0 to 255. Our proposed methodology employs 16 × 16 matrices to represent the four channels (red, green, blue, and alpha) of a 32-bit color image, strategically utilizing specific grids for channel encryption. The top-left and bottom-right grids facilitate the encryption of the red and alpha channels, respectively, while the top-right and bottom-left grids are employed for encrypting the green and blue channels. The algorithm initiates by extracting decimal values from each pixel in the source image, mapping them to their corresponding positions in the matrices. A subsequent right circular shift operation on each pixel, determined by its row and column coordinates, is performed to prevent the encryption of areas with uniform color. To enhance security further, we employ the Four-square cipher method to encrypt the decimal values of the pixels. In the confusion stage, we apply the Arnold Cat Map transformation to strategically rearrange the position of all pixels, introducing an additional layer of complexity. Rigorous assessments using various security criteria were conducted to evaluate our algorithm's performance against common attacks, yielding consistently excellent results. Our method demonstrated superior outcomes, including a 25 % to 44 % increase in resistance to common attacks compared to existing methods.

Abstract In the present study, we aim to propose an effective and robust ensemble-learning approach with stacked generalization for image segmentation. Initially, the input images are processed for feature extraction and edge detection using the Gabor filter and the Canny algorithms, respectively; our main goal is to determine the most feature descriptions. Subsequently, we applied the stacking generalization technique, which is generally built with two main learning levels. The first level is composed of two algorithms that give good results in the literature, namely: LightGBM (Light Gradient Boosting Machine) and SVM (support vector machine). The second level is the meta-model in which we use a predictor model that takes the base-level predictions to improve the accuracy of the final prediction. In the stacked generalization process, we use the Extreme Gradient Boosting (XGBoost); it takes as input the sub-models’ outputs to better classify each pixel of the image to give the final prediction. Today, several research works exist in the literature using different machine learning algorithms; in fact, instead of trying to find a single efficient and optimal learner, ensemble-based techniques take the advantage of each basic model; they integrate their outputs to obtain a more consistent and reliable learner. The result obtained from the models of individuals and our proposed approach is compared using a set of evaluation measures for image quality such as IoU, DSC, CC, SSIM, SAM, and UQI. The evaluation and a comparison of the results obtained showed more consistent predictions for the proposed model. Thus, we have made a comparison with some recent deep learning-based unsupervised segmentation methods. The evaluation and a comparison of the results obtained showed more coherent predictions for our stacked generalization in terms of precision, robustness, and consistency.

Phosphorus compounds are biologically active molecules and exhibit a wide range of applications in the area of industrial, agricultural and medicinal chemistry. In this context, a green synthetic approach was developed for the synthesis of α-Aminophosphonates 1 (a-k) in good yields through one-pot multi-component reaction. All synthesized compounds were screened for their in vitro antioxidant activity with different methods using 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical (OH˙), ferrous reducing power (FRP) and ferrous ion chelating (FIC) abilities. α-Aminophosphonates showed significant antioxidant activity that could suggest them for other biological uses. [ABSTRACT FROM AUTHOR]

A biological invasion of non-native plants is spreading into our natural areas and rights-of way. In the present work, Melia azedarach (Meliaceae) known for its high allelopathic potential is used to investigate its bio-pesticide capacity on the common model used in bioassays: Raphanus sativus (R. sativus). Exposure of R. sativus to M. azedarach (aqueous/ethanolic) leaves extracts result on toxicity exclusively toward roots. The roots inhibition was dose dependent and more pronounced for ethanolic extract. Allelochemicals of M. azedarach ethanolic extracts induced an oxidative stress in radish focalized by a decrease on enzymatic anti-oxidant defense such superoxide dismutase (SOD) activity. However, the stimulation of phenyl-alanine ammonialyase (PAL) activity and the subsequent increase in phenols content failed to alleviate R. Sativus roots oxidative stress. Importantly, the result of M. azedarach leaves extracts inducing oxidative imbalance in roots seemed to be harmful in vivo on R. sativus but exceeded its antioxidant abilities in vitro. M. azedarach invasive species might be valorized, in Tunisia, by developing "root killers" bio-herbicides and enhancing biological proprieties of received plant. [ABSTRACT FROM AUTHOR]

Phosphorus compounds are biologically active molecules and exhibit a wide range of applications in the area of industrial, agricultural and medicinal chemistry. In this context, a green synthetic approach was developed for the synthesis of α-Aminophosphonates 1 (a-k) in good yields through one-pot multi-component reaction. All synthesized compounds were screened for their in vitro antioxidant activity with different methods using 1,1-diphenyl-2- picrylhydrazyl (DPPH), hydroxyl radical (OH˙), ferrous reducing power (FRP) and ferrous ion chelating (FIC) abilities. α-Aminophosphonates showed significant antioxidant activity that could suggest them for other biological uses. [ABSTRACT FROM AUTHOR]

The ink secretion of molluscan species was identified as one of the novel sources of bioactive compounds. The present study aims to evaluate the in vitro antioxidant activity of Aplysia depilans ink extract. The antioxidant activity of ink extract were evaluated using 2,2- diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, Hydroxyl radical scavenging activity, Ferric ion reducing power (FRP) and Ferrous ion chelating (FIC) activity. The results from the present work revealed the strongest antioxidant activity of Aplysia depilans ink. The electrophoretic profile showed band with molecular weight of 60 kDa. The highest antioxidant activity in ink extract probably may be due to the presence of this protein with lower moleculair weight.

The relationship between fruit position, ripening stage, and variety has not been well studied in pepper plants. To understand the interaction of these factors, a diversity of phytochemical traits as well as antioxidant activity were investigated with agronomic traits in eleven hot pepper varieties collected from the upper and lower parts of the plant and harvested at three maturity stages (green, orange, and red). Capsaicin content (CAP) showed a relatively high genetic effect; on the contrary, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity were more affected by the ripening stage and fruit position. The CAP values ranged from 0.29 ('FKbM') to 0.77 ('Bka') mg CAP equivalents g -1 DW. The ripening stage was the predominant factor for TPC, TFC, DPPH, and FRAP. There was no significant interaction between A × FP, A × RS, and FP × RS for all agro-morphological fruit traits. Variety, fruit position, and ripening stage effects are more significant than all interactions calculated. Lower fruit positions in all samples showed a maximum fruit size, whereas phytochemical traits and yield per plant were relevant in the upper parts, and Phytochemical traits and yield per plant were significantly correlated. From PCA and cluster analysis, all varieties showed the highest biochemical and antioxidant levels with moderate fruit size, except the 'Bel' variety that showed the smallest fruit traits with high yields, and the 'FKbM' and 'FKbK' varieties that showed the highest fruit size but low yields. This study supplies information to identify interesting cultivars with considerable levels of bioactive and phytochemical metabolites, which is useful for breeding programs of novel varieties.

We studied the effect of Ajuga iva leaves extract (AIE) on the intestinal absorption, motricity and its antioxidant capacity against diarrhea. Wistar rats were divided and received either: castor oil (CO), CO and loperamide or CO and different doses of AIE. AIE prevented dose-dependently CO-induced diarrhea. AIE at 800 mg/kg showed inhibition efficiency on defecation and diarrhea. The pro-oxidant effect of the CO in the small intestine was inhibited significantly in presence of AIE: increasing glutathione peroxidase (GPx) activity and lowering oxygen free radicals (OH°, O 2 °-), carbonyl protein and malondialdehyde (MDA) levels. However, co-administration of AIE in castor oil-exposed groups significantly increased the intestinal contents of calcium and magnesium. AIE exhibits significant anti-diarrheal activity, related in part to its antioxidant properties. Our investigation also provides experimental evidence for the traditional use of this medicinal plant in the treatment of diarrhea., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Published by Elsevier Ltd.)

Vacuoles have been shown to undergo deep modifications in relation to plant developmental stages and in the maintaining the cellular homeostasis. In this context, we studied the variations of the vacuolar membrane size and α-TIP aquaporin distribution at early and advanced seed stages of maturation, germination and embryo growth in Vicia faba cotyledon storage cells., (Copyright © 2017 Elsevier GmbH. All rights reserved.)

Based on the broad spectrum of biological activities associated with organophosphates, a novel type of this class of compounds was synthesized, bearing a nitrile group, from the sodium alkoxide-catalyzed reaction of dialkylphosphites with γ-ketonitriles at 80°C under solvent-free conditions. A reaction mechanism involving a phospha-Brook type rearrangement is proposed. Eight title compounds were investigated for their in vitro inhibitory potency and selectivity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) using Ellman's spectrophotometric method. The synthesized derivatives exhibited mostly a moderate activity against both cholinesterases. The IC 50 values for BChE were in a smaller concentration range (5.96-23.35µM) compared to those for AChE inhibition (9.61-53.74µM). The diethyl-3-cyano-1-p-tolylpropylphosphate which displayed the higher dual inhibitory potency towards both cholinesterases could be considered as a potential candidate for developing new drugs to treat Alzheimer's disease., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The present investigation aimed to study the antioxidant activity and hepatoprotective effects of ethyl acetate extract of R. oxyacantha root cortex (RE) against DDT-induced liver injury in male rats. The RE exhibited high total phenolic, flavonoid and condensed tannins contents. The antioxidant activity in vitro systems showed a significant potent free radical scavenging activity of the extract. The HPLC finger print of R. oxyacantha active extract showed the presence of five phenolic compounds with higher amounts of catechol and gallic acid. The in vivo results showed that a single intraperitoneal administration of DDT enhanced levels of hepatic markers (ALT, AST and LDH) in serum of experimental animals. It also increased the oxidative stress markers resulting in increased levels of the lipid peroxidation with a significant induction of SOD and GPx, metallothioneins (MTs) and a concomitant decrease of non protein thiols (NPSH) in liver. However, pretreatment of rats with RE at a dose of 150 and 300mg/kg body weight significantly lowered serum transaminases and LDH in treated rats. A significant reduction in hepatic thiobarbituric reactive substances and a decrease in antioxidant enzymes activities and hepatic MTs levels by treatment with plant extract against DDT, were observed. These biochemical changes were consistent with histopathological observations, suggesting marked hepatoprotective effect of RE with the two doses used. These results strongly suggest that treatment with ethyl acetate extract normalizes various biochemical parameters and protects the liver against DDT-induced oxidative damage in rats and thus help in evaluation of traditional claim on this plant., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Obesity is associated with an oxidative stress status, which is defined by an excess of reactive oxygen species (ROS) vs. the antioxidant defense system. We report in this present work, the link between fat deposition and oxidative stress markers using a High Fat Diet-(HFD) induced rat obesity and liver-oxidative stress. We further determined the impact of chronic administration of 3-keto-1, 5-BPs 1 (a & b) (40μg/kg/8 weeks/i.p.) on liver's level. In fact, exposure of rats to HFD during 16 weeks induced body and liver weight gain and metabolic disruption with an increase on liver Alanine amino transférase (ALAT) and Aspartate aminotransférase (ASAT) concentration. HFD increased liver calcium level as well as free iron, whereas, it provoked a decrease on liver lipase activity. HFD also induced liver-oxidative stress status vocalized by an increase in reactive oxygen species (ROS) as superoxide radical (O 2 ), hydroxyl radical (OH) and Hydrogen peroxide (H 2 O 2 ). Consequently, different deleterious damages as an increase on Malon Dialdehyde MDA, Carbonyl protein PC levels with a decrease in non-protein sulfhydryls NPSH concentrations, have been detected. Interestingly, our results demonstrate a decrease in antioxidant enzymes activities such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx) and peroxidases (POD). Importantly, 3-keto-1,5-bisphosphonates treatment corrected the majority of the deleterious effects caused by HFD, but it failed to correct some liver's disruptions as mineral profile, oxidative damages (PC and NPSH levels) as well as SOD and lipase activities. Our investigation point that 3-keto-1,5-bisphosphonates could be considered as safe antioxidant agents on the hepatic level that should also find other potential biological applications., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

Objectives: To evaluate the contributions of the some quantum dots in different biological uses in order to valorizes such nanomaterials for further applications., Methods: Zinc sulfide ZnS nanoparticles were synthesized in aqueous medium at pH constant, the obtained nanoparticles has been characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier Transform Infra-red (FTIR) spectroscopies. Zinc sulfide nanoparticles were screened for their antibacterial and antifungal profiling and tested for antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical (OH) and hydrogen peroxide (H2O2) scavenging activity, ferric reducing power (FRP) assay and ferrous ion chelating (FIC) methods., Results: The sizes of the crystallites were estimated to 3 nm using the Debye-Scherrer formula based on the XRD data. The shape was identified to be quasi-spherical with agglomerated particles. The obtained ZnS quantum dots present an antioxidant activity especially in oxido-reduction power, and can be used for species profiling either for bacteria and fungus., Conclusion: It was found that ZnS nanoparticles showed relatively higher antioxidant activities and antibacterial with an antifungal behavior which proves that this nanomaterials can react at the interface with the life entities., (Copyright © 2016 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.)

Obesity has become a leading global health problem owing to its strong association with a high incidence of oxidative stress. Many epidemiologic studies showed that an antioxidant supplementation decreases the state of oxidative stress. In the present work, a HFD-induced rat obesity and oxidative stress were used to investigate the link between fat deposition and serum-oxidative stress markers. We also studied the effect of a chronic administration of 3-keto-1,5-bisphosphonates 1 (a & b) (40 μg/kg/8 weeks/i.p.). Exposure of rats to HFD during 16 weeks induced fat deposition, weight gain and metabolic disruption characterized by an increase in cholesterol, triglyceride and glycemia levels, and a decrease in ionizable calcium and free iron concentrations. HFD also induced serum-oxidative stress status vocalized by an increase in ROS (H2 O2 ), MDA and PC levels, with a decrease in antioxidant enzyme activity (CAT, GPx, SOD). Importantly, 3-keto-1,5-bisphosphonates corrected all the deleterious effects of HFD treatment in vivo, but it failed to inhibit lipases in vitro and in vivo. These studies suggest that 3-keto-1,5-bisphosphonates 1 could be considered as safe antioxidant agents that should also find other potential biological applications., (© 2014 John Wiley & Sons A/S.)

Herein we report an efficient, simple and green synthesis of novel types of α-hydroxyphosphonates bearing a nitrile group, from the reaction of γ-ketonitriles with dialkyl phosphites in the presence of magnesium oxide as solid support, under solvent-free conditions. All the title compounds were screened for their antioxidant activity by 1,1-diphenyl-2- picrylhydrazyl (DPPH), hydroxyl radical, reducing power and ferrous ion chelating (FIC) methods and they showed significant antioxidant activity.

Background: Mannich bases are an important class of compounds in medicinal chemistry with a wide spectrum of biological activities, however, knowledge on their toxicity is limited., Materials and Methods: Two Mannich base hydrochlorides 1a (2-thienyl-β-dimethylaminoethyl ketone hydrochloride) and 1b (β-dimethylaminopropiophenone hydrochloride) were synthesized and characterized on the basis of their infrared and nuclear magnetic resonance spectral data. The potential effects of the synthesized compounds (5 mg/kg, i.p, during 30 days) on relative weight, hematological parameters, biochemical parameters, and neurotoxicity were tested using male Wistar rat., Results: The results showed that compound 1b alters body weight on the first 10 days (182%, P < 0.01) and on the last 10 days (107%, P < 0.01) of treatment. The same treatment decreases food intake (P < 0.01) and increases water intake (P < 0.05). Both compounds induced a deficit on rotarod test manifested by a decrease of grasping time (1a: 65.33%, P < 0.01; 1b: 60.55%, P < 0.01) and fall time (1a: 59.75%, P < 0.01; 1b: 56.81%, P < 0.01) only on the last day of training. Moreover, Mannich base 1b decreases the liver relative weight (22.24%, P < 0.01). It was also observed that both products decrease the total serum cholesterol (Ch) levels (1a: 52.87%, P < 0.01; 1b: 64.70%, P < 0.01). Interestingly, compounds 1a and 1b affect hematological parameters manifested by an increase of the number of white blood cells (1a: 32.29%, P < 0.05; 1b: 20.64%, P < 0.05) and red blood cells (RBCs) (1a: 12.57%, P < 0.05; 1b: 20.11%, P < 0.05), an increase of red cell hemoglobin concentration (1a: 10.48%, P < 0.05; 1b: 16.12%, P < 0.05) and of the volume occupied by RBCs or hematocrit (1a: 18.28%, P < 0.05; 1b: 15.56%, P < 0.05), and an increase of the number of platelets (1a: 16.80%, P < 0.05; 1b: 39.96%, P < 0.05) accompanied by a decrease in hemoglobin level only with the compound 1a (7.41%, P < 0.05)., Conclusion: These results show that both compounds 1a and 1b induced a hypoxia status associated to low level of Ch and liver toxicity. The deficit observed by rotarod could be explained by the myorelaxant effect of the used products.