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2. RGB-to-hyperspectral conversion for accessible melanoma detection: A CNN-based approach

Author

Bsharat Sondos Mahmoud, Abouelnour Sana, Ahmed Ragad, Elkhatib Mariam, Gaber Sama, Shehieb Wessam, Arshad Kamran, and Assaleh Khaled

Subjects
hyperspectral imaging, melanoma, neural networks, deep-learning, machine learning, confusion matrix, principal component analysis, Science, Electronic computers. Computer science, QA75.5-76.95
Abstract

One major difficulty facing the healthcare industry is the early and precise detection of melanoma. With its capacity to record a broad spectrum of electromagnetic wavelengths, hyperspectral imaging (HSI) is a promising technique for accurate melanoma diagnosis. However, the limited accessibility of HSI technology prevents it from being widely used. This article introduces a novel method for converting readily available red green blue (RGB) images to their hyperspectral counterparts using convolutional neural networks (CNNs). Through this conversion process, spectral information is improved, enabling a more thorough examination to detect melanoma. Principal component analysis (PCA) aids the machine learning algorithm in differentiating between melanoma and healthy moles in the classification model. Accuracy is significantly increased when spot detection and PCA are combined; Naïve Bayes achieves 76% accuracy in this way. These models are used in the developed web-based program SkinScan for real-time melanoma analysis, providing a useful and accessible solution. This work emphasizes how CNN-driven RGB-to-HSI conversion might improve melanoma detection accuracy and accessibility.

Published
2024
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27. Pinning Behaviour of Nano Nonmagnetic CuO, SnO2 and Magnetic Mn3O4 Substitutions in YBCO Bulk Superconductors.

Author

Salama, A. H., El-Hofy, M., Rammah, Y. S., and Elkhatib, M.

Subjects
SUPERCONDUCTORS, MAGNETIC properties of metallic oxides, FLUX pinning
Abstract

Nanoparticles were doped into YBCO samples as pinning centres by chemical solid-state reaction. High magnetic moment nanoparticles Mn3O4 and nonmagnetic nanoparticles SnO2 and CuO were prepared with a concentration of 0.1, 0.2, 0.3, 0.4 and 0.5 mass-%, respectively by a co-precipitation method. The microstructure and electrical properties of the doped YBCO samples was investigated. Increasing SnO2 in the YBCO samples from 0.1 mass-% to 0.5 mass-% tended together at one point through the sample and appeared as a defect that affects the lattice parameters of the YBCO crystal, which in turn led to degradation of the critical temperature Tc, which did not differ much from the CuO effect, which was added in the same proportions, but it was distributed through the samples. On the contrary, Mn3O4 acted as nano- pinning centre through the sample, which in turn initially led to an improvement of the critical temperature Tc. Further increase of Mn3O4 content, Tc began to decay which is due to the distortion of the lattice parameters of the YBCO crystal. [ABSTRACT FROM AUTHOR]

Published
2016
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39. Pinning Behaviour of Nano Nonmagnetic CuO, SnO2and Magnetic Mn3O4Substitutions in YBCO Bulk Superconductors

Author

Salama, A., El-Hofy, M., Rammah, Y., and Elkhatib, M.

Abstract

Nanoparticles were doped into YBCO samples as pinning centres by chemical solid-state reaction. High magnetic moment nanoparticles Mn3O4and nonmagnetic nanoparticles SnO2and CuO were prepared with a concentration of 0.1, 0.2, 0.3, 0.4 and 0.5 mass-%, respectively by a co-precipitation method. The microstructure and electrical properties of the doped YBCO samples was investigated. Increasing SnO2in the YBCO samples from 0.1 mass-% to 0.5 mass-% tended together at one point through the sample and appeared as a defect that affects the lattice parameters of the YBCO crystal, which in turn led to degradation of the critical temperature Tc, which did not differ much from the CuO effect, which was added in the same proportions, but it was distributed through the samples. On the contrary, Mn3O4acted as nano-pinning centre through the sample, which in turn initially led to an improvement of the critical temperature Tc. Further increase of Mn3O4content, Tcbegan to decay which is due to the distortion of the lattice parameters of the YBCO crystal.

Published
2016
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44. Kinetic and mechanistic study of N-aminopiperidine formation via the raschig process.

Author

Darwich, C., Elkhatib, M., Pasquet, V., and Delalu, H.

Subjects
*CHEMICAL kinetics, *AMINO compounds, *PIPERIDINE, *RING formation (Chemistry), *CHEMICAL reactions, *CHLORAMINES, *PH effect
Abstract

Formation of N-aminopiperidine (NAPP) in the reaction of monochloramine with piperidine was studied by varying the reagents concentrations, pH and temperature. The study was carried out in diluted solutions, recording simultaneously monochloramine concentration by UV spectrophotometry at 243 nm and hydrazine concentration at 237 nm after treatment with formaldehyde. The presence of two competitive reactions: formation of NAPP and a complex parallel reaction limiting the yield of hydrazine, was established. Reaction products were characterized by GC/MS analysis. The rate constant of NAPP formation and activation parameters were determined, k1 = 56 × 10 −3 M −1 s −1 (25°C) and k1 = 9.3 × 10 6 exp(−46.5/ RT) M −1 s −1, respectively. [ABSTRACT FROM AUTHOR]

Published
2013
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47. Synthesis and NMR investigation of 3,4diazabicyclo4.3.0non2ene and N,Nazo3azabicyclo3.3.0octane. Xray crystal structure analysis of a new tetrazene derivative

Author

Delalu, H., Elkhatib, M., Peyrot, L., Fenet, B., and Mentzen, B. F.

Abstract

3,4Diazabicyclo4.3.0non2ene and N,Nazo3azabicyclo3.3.0octane are the main products of the oxidation of Namino3azabicyclo3.3.0octane by chloramine. These new compounds have been isolated and characterized. A structural study has been performed with the goal of establishing the cis—transconfiguration at the bicyclic junction. Multinuclear proton decoupling carried out on the endocyclic hydrazone has allowed the determination of the coupling constant of the bridgehead hydrogens. A low temperature conformational study shows splitting of the 13C signal of the carbon atom located α with respect to the ammonia nitrogen. This result, consistent with a cisstructure, was confirmed by a nmr analysis conducted on the solid tetrazene derivative. The Xray data collection on a single cyrstal of the tetrazene has permitted us to determine the crystallographic properties of this compound. Data processing by direct methods reveals that the geometry of the molecule presents a cisconfiguration for the bicyclic bridge link and a transone for the azo group, confirming thus the main results obtained by nmr studies.

Published
1999
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48. Kinetics of dehydrohalogenation of <TOGGLE>N</TOGGLE>-chloro-3-azabicyclo[3,3,0]octane in alkaline medium. NMR and ES/MS evidence of the dimerization of 3-azabicyclo[3,3,0]oct-2-ene

Author

Elkhatib, M., Peyrot, L., Scharff, J. P., and Delalu, H.

Abstract

The formation of 3-azabicyclo[3,3,0]oct-2-ene in the course of the synthesis of N-amino-3-azabicyclo[3,3,0]octane using the Raschig process results from the following two consecutive reactions: chlorine transfer between the monochloramine and the 3-azabicyclo[3,3,0]octane followed by a dehydrohalogenation of the substituted haloamine. The kinetics of the reaction were studied by HPLC and UV as a function of temperature (15 to 44°C), and the concentrations of NaOH (0.1 to 1 M) and the chlorinated derivative (1 to 4×10−3 M). The reaction is bimolecular (k=103×10−6 M−1 s−1; ΔH0#=89 kJ mol−1; and ΔS0#=−33.6 J mol−1 K−1) and has an E2 mechanism. The spectral data of 3-azabicyclo[3,3,0]oct-2-ene were determined. IR, NMR, and ES/MS analysis show dimerization of the water-soluble monomer into a white insoluble dimer. © 1998 John Wiley & Sons, Inc. Int J Chem Kinet: 30: 129–136, 1998.

Published
1998
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