89 research outputs found

    A rule-based machine learning model for financial fraud detection

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    Financial fraud is a growing problem that poses a significant threat to the banking industry, the government sector, and the public. In response, financial institutions must continuously improve their fraud detection systems. Although preventative and security precautions are implemented to reduce financial fraud, criminals are constantly adapting and devising new ways to evade fraud prevention systems. The classification of transactions as legitimate or fraudulent poses a significant challenge for existing classification models due to highly imbalanced datasets. This research aims to develop rules to detect fraud transactions that do not involve any resampling technique. The effectiveness of the rule-based model (RBM) is assessed using a variety of metrics such as accuracy, specificity, precision, recall, confusion matrix, Matthew’s correlation coefficient (MCC), and receiver operating characteristic (ROC) values. The proposed rule-based model is compared to several existing machine learning models such as random forest (RF), decision tree (DT), multi-layer perceptron (MLP), k-nearest neighbor (KNN), naive Bayes (NB), and logistic regression (LR) using two benchmark datasets. The results of the experiment show that the proposed rule-based model beat the other methods, reaching accuracy and precision of 0.99 and 0.99, respectively

    Aloe Vera Assisted Green Synthesis of Ag and Cu CO-Doped Zno Nanoparticles and a Comprehensive Analysis of Their Structural, Morphological, Optical, Electrical and Antibacterial Properties

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    This study investigates the potential of utilizing Aloe vera-assisted green synthesis with transition metal dopants of Ag and Cu for greater efficiency and sustainability in advanced scientific applications utilizing ZnO nanoparticles. Samples were prepared using the co-precipitation method, maintaining a basic pH media of 10. Aloe vera gel extract was chosen for its acclaimed role as a stabilizing and reducing agent and its proven antioxidant, antibacterial, and anticancer properties. The XRD report revealed the hexagonal Wurtzite crystal structure of nanoparticles, exhibiting a crystallite size range of 17-23 nm with substantial alterations in lattice parameters, dislocation density, and bond lengths when dopants were added. Additionally, EDX analysis confirmed the perfect doping of Ag and Cu in ZnO without any impurities. SEM analysis indicated a reduction in agglomeration, accompanied by a transition in particle morphology from columnar to globular. Additionally, the optical study showed a band gap range of 3.18-3.27 eV, confirming it to be a wide band gap semiconductor. The effect of dopants resulted in an increase in transparency and band gap, while a decrease in absorption coefficient in the visible wavelength region. With increasing temperature, a decline in electrical resistivity was noted, with co-doped nanoparticles consistently exhibiting the lowest resistivity, affirming semiconductor characteristics. Most importantly, A remarkable antibacterial efficacy was noticed at low concentrations against gram-positiv

    Understanding the Enhanced Stability of Bromide Substitution in Lead Iodide Perovskites

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    Lead halide perovskites have rapidly emerged as candidate materials for high-performing solar cells, but show serious issues related to long-term stability. Methylammonium (MA) lead perovskites with mixed iodide-bromide compositions, MAPb(I1-xBrx)3, are reported to exhibit improved stability, but the origin of such behavior is not fully understood. Here, we report new insights into the degradation properties of MAPb(I1-xBrx)3 using ab initio simulations and a range of spectroscopic techniques. Absorbance spectroscopy shows that as the Br content increases, the material stability toward oxygen and light increases. Isothermal gravimetric analysis and time-resolved single photon counting show that the amount of oxygen incorporation into perovskite films decreases significantly with increasing Br content. Ab initio simulations indicate that the degradation reaction involving superoxide species is energetically exothermic for pure MAPbI3 but becomes less favorable with increasing Br content with an endothermic energy for pure MAPbBr3, suggesting that the degradation of MAPbBr3 in the presence of oxygen and light is unfavorable. The simulations indicate shorter N-H...Br hydrogen bonds between the MA+ cation and Br ions, which would promote greater structural stability upon bromide substitution. Thin-film passivation with iodide salts is shown to enhance the stabilities of mixed-halide perovskite films and solar cell devices. The greater fundamental understanding of mixed iodide-bromide systems gained from this study is important for the future design of stable perovskite solar cells.</p

    Clinico-epidemiological study of childhood psoriasis

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    The clinico-epidemiological data of 276 childhood psoriasis were studied. The mean age was 7.64 years (range 1 day to 15 years). There was no complain of any discomfort in 198 cases. Itching was present in 67 cases and burning in 11 cases. Plaque psoriasis was the most common type (68.8%) followed by guttate (18.8%). Erythrodermic and pustular psoriasis were found in 2.2% and 1.5% cases. Scalp was the most frequently affected site (75.36%) followed by extensors of extremities (41.3%), trunk (37.7%), palm and/or sole (13.0%) and diaper area (11.6%). Nail involvement was found only in 8%, joint was affected in 3.6% and only 2.2% children with psoriasis were erythrodermic. In Bangladeshi children with psoriasis, plaque is the most common type and scalp is the mostly affect site. Nail and joint involvement is less common. Pustular and erythrodermic psoriasis is rare

    A Follow-Up Study on the Efficacy of the Homeopathic Remedy Arsenicum album in Volunteers Living in High Risk Arsenic Contaminated Areas

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    In continuation of our short-term pilot studies reported earlier, results on certain toxicity biomarkers in volunteers who continued to take the potentized Arsenicum album 200C till 2 years are presented. Out of some 130 “verum”-fed volunteers of pilot study, 96 continued to take the remedy till 6 months, 65 till 1 year and 15 among them continued till 2 years. They provided samples of their urine and blood at 6 months, 1 year and finally at 2 years. None out of 17 who received “placebo” turned up for providing blood or urine at these longer intervals. Standard methodologies were used for determination of arsenic content in blood and urine, and for measurement of toxicity biomarkers like acid and alkaline phosphatases, alanine and aspartate amino transferases, lipid peroxidation and reduced glutathione and anti-nuclear antibody titers. Most of the volunteers reported status quo maintained after the improvement they achieved within the first 3 months of homeopathic treatment, in respect of their general health and spirit, and appetite and sleep. A few with skin symptoms and burning sensation, however, improved further. This was supported by the data of toxicity biomarkers, levels of all of which remained fairly within normal range. Therefore, administration of Arsenicum album 200C considerably ameliorates symptoms of arsenic toxicity on a long-term basis, and can be recommended for interim use, particularly in high risk remote villages lacking modern medical and arsenic free drinking water facilities. Similar studies by others are encouraged
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