Hassen Ghalila

@article{mbogning_feudjio_4589,

title = {Fluorescence Spectroscopy Coupled with Artificial Neural Networks to Detect Refined Palm Oil Adulteration in Extra Virgin Olive Oil: A Case Study on Commercialized Oils in Cameroon},

author = {William Mbogning Feudjio and Ikram Khemiri and Aymar Rodrigue Fogang Mba and Sagesse Bel-Christ Kogniwali-Gredibert and Gabrielle Muke Ngome and Lionel José Wankam and Gilbert Yvon Mbesse Kongbonga and Kenfack Assongo and Hassen Ghalila and Mama Nsangou},

url = {https://doi.org/10.1007/s12161-026-03250-1},

year  = {2026},

date = {2026-09-01},

journal = {Food Analytical Methods},

volume = {19},

pages = {326},

abstract = {The adulteration of extra virgin olive oil remains a major problem for the food industry. This practice has both health and economic consequences. In countries which import extra virgin olive oil, the problem is even more serious. The objective of this study was to use a laboratory assembled fluorometer to detect the presence of refined palm oil in extra virgin olive oil commercialized in Cameroon. The fluorescence spectra obtained with an excitation wavelength of 380 nm reveal two principal emission peaks: one at 497.18 nm, attributed to oxidation products in refined palm oil, and another at 673.75 nm, attributed to chlorophylls in extra virgin olive oil. The fluorescence intensities of the adulterated samples increased with the concentration of refined palm oil in extra virgin olive oil. Principal component analysis, employing two principal components that accounted for 95% of the total variance, enabled clear visualization of the clusters of adulterated samples. The risk of misclassification between classes, as indicated by principal component analysis, was mitigated by a self-organizing maps neural network. Finally, a multilayer perceptron neural network demonstrated high efficacy in predicting with a determination coefficient of 0.998, the concentration of refined palm oil in extra virgin olive oil. To the best of our knowledge, this study represents the first application of fluorescence spectroscopy coupled with artificial neural networks to detect the adulteration of extra virgin olive oil with refined palm oil. The results obtained prove the significance of fluorescence and neural network tools for the reliable characterization of vegetable oils, opening promising perspectives for their application in the food industry.},

keywords = {},

pubstate = {online},

tppubtype = {article}

}

@article{mbogning_feudjio_4587,

title = {Practical implementation of the wavelength recalibration of a UV-visible spectrometer through the user manual: a simple approach to select the reference wavelengths},

author = {William Mbogning Feudjio and Rihem Nouir and Sagesse Bel-Christ Kogniwali-Gredibert and Gilbert Yvon Mbesse Kongbonga and Hassen Ghalila and Mama Nsangou},

url = {https://doi.org/10.1364/AO.608579},

year  = {2026},

date = {2026-08-01},

journal = {Applied Optics},

volume = {65},

number = {24},

pages = {8276-8279},

abstract = {Wavelength drift in charge-coupled device spectrometers causes incorrect peak assignment. This work presents a practical method to recalibrate a drifted Ocean Optics USB2000 using the manufacturer's procedure. The 365.01 nm line and the unresolved 576.96/579.07 nm doublet of an Hg-Ar lamp served as anchors to identify reference wavelengths and assign pixel numbers. Third-order polynomial regression gave the coefficients: intercept = 190.804969,

,

, and



, which were inserted into the memory of the spectrometer via USB Programmer. The mean residual error decreased from 9 to 2 nm, 1 nm above specified accuracy. This work serves as a useful aid for spectroscopists.



© 2026 Optica Publishing Group. All rights, including for text and data mining (TDM), Artificial Intelligence (AI) training, and similar technologies, are reserved.},

keywords = {},

pubstate = {online},

tppubtype = {article}

}

@article{mbogning_feudjio_4302,

title = {Storage monitoring of Petit grain and Black pepper essential oils: An exploratory analysis by three-dimensional fluorescence and chemometrics},

author = {William Mbogning Feudjio and Ikram Khemiri and Hassen Ghalila and Mama Nsangou},

url = {https://doi.org/10.1016/j.microc.2026.117907},

year  = {2026},

date = {2026-05-01},

journal = {Microchemical Journal},

volume = {224},

pages = {117907},

abstract = {The objective of this study was to evaluate the potential of spectroscopic and chemometric approaches to monitor

heat and light induced effects during the storage of Petit grain and Black pepper essential oils. Three-dimensional

fluorescence spectroscopy highlighted characteristic emission bands, notably at 340 nm following excitation at

310 nm, which provided discriminatory features in Petit grain essential oil storage. Principal Component

Analysis, with two principal components explaining 85 % of the total variance, allowed a clear differentiation

between Petit grain essential oils of different storage types and times. Parallel Factor Analysis unveiled, with high

core consistency (89.36 %) and explained variance (98.90 %), the presence of three fluorophores in Black pepper

essential oil samples. The monitoring of these fluorophore concentrations toward storage revealed a non-linear

evolution with a drastic regression, of up to 88.71%, after four months of light storage. These findings

demonstrate the relevance of three-dimensional fluorescence and chemometrics tools for the reliable characterization

of natural products. They open promising perspectives for their application in quality control,

authentication, and traceability within the food and pharmaceutical industries.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{cherni_4303,

title = {Hair Fluorescence Spectroscopy as a Non-Invasive Biomarker for Diagnosis and Remission Monitoring in Systemic Lupus Erythematosus},

author = {Imen Cherni and Sarra Ben Brik and Wanian M Alwanian and Rihem Nouir and Mehdi Somai and Fatma Boussema and Hassen Ghalila and Sami Hamzaoui and Zohra Aydi and Fatma Daoud},

url = {https://doi.org/10.1177/00037028261421633},

year  = {2026},

date = {2026-04-01},

journal = {Applied Spectroscopy},

volume = {80},

number = {4},

pages = {391-398},

abstract = {Hair fluorescence spectroscopy was evaluated as a novel, non-invasive biomarker for the diagnosis and disease monitoring of systemic lupus erythematosus (SLE). Hair samples were collected from 47 female patients with SLE and 49 age-matched healthy controls (HC), with patients stratified into three clinical groups: active flare, remission of six months to three years (R6M-3Y group), and remission of more than three years (R?>?3Y group). Fluorescence emission spectra of hair strands were recorded under ultraviolet excitation and analyzed using multivariate statistical methods, including principal component analysis and hierarchical clustering, to assess group discrimination. The fluorescence profiles differed significantly between SLE patients and the HC group, and within the SLE cohort, spectral signatures varied according to disease activity, enabling discrimination between flare and remission (low disease activity) states. Patients in long-term remission (R?>?3Y) showed partial convergence toward the HC group, suggesting progressive normalization over time. Overall, hair fluorescence spectroscopy emerges as a non-invasive, inexpensive, and stable biomarker reflecting both disease presence and remission dynamics in SLE, with potential to complement existing clinical and laboratory indices and to provide rheumatologists with a novel tool for longitudinal disease monitoring.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{hamzaoui_4043,

title = {Nail fluorescence analysis for osteoporosis diagnosis: Correlation between nail collagen abundance and T-score},

author = {Sami Hamzaoui and Imen Cherni and Sabrine Kouki and Hassen Ghalila and Imen Rachdi and Fatma Boussema and Fatma Daoued and Mehdi Somai},

url = {https://doi.org/10.1080/10739149.2025.2515441},

year  = {2026},

date = {2026-02-01},

journal = {Instrumentation Science & Technology},

volume = {54},

number = {2},

pages = {206-220},

abstract = {This study aimed to evaluate the efficacy of Front-Face

Fluorescence Spectroscopy (FFFS), in combination with chemometric

techniques, as a preliminary, rapid, and cost-effective

approach for the diagnosis of osteoporosis (OP). Specifically, the

research investigated the capability of this method to differentiate

between osteoporotic and healthy individuals by analyzing

nail fluorescence spectra and examining correlations between

the fluorescence intensities of nail proteins and participants'

bone mineral densities (BMD). The study population was divided

into three groups: 30 women diagnosed with OP, 30 with osteopenia,

and 30 healthy controls. Classification was based

on T-score values obtained through Dual-Energy X-ray

Absorptiometry (DXA). The results demonstrated a progressive

decline in nail fluorescence emission intensity from healthy individuals

to those with osteoporosis. Importantly, healthy and

osteoporotic subjects could be clearly distinguished based on

the relative peak intensities of specific proteins within the fluorescence

spectra of their nails. However, a partial overlap in fluorescence

peak intensities was observed between the osteopenic

and osteoporotic groups. Spearman's correlation analysis

revealed a strong positive association between collagen fluorescence

intensities in nails and T-score values among participants

with osteopenia and OP. These findings suggest that nail

collagen fluorescence has potential as a practical, noninvasive

biomarker for the early detection and monitoring of BMD

deterioration},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{bourdier_4044,

title = {Reduction of multiple filamentation due to atmospheric turbulence during the propagation of a laser pulse},

author = {Alain Bourdier and Hassen Ghalila and Olivier Delage},

url = {https://doi.org/10.1016/j.rinp.2025.108371},

year  = {2025},

date = {2025-09-01},

journal = {Results In Physics},

volume = {76},

pages = {108371},

abstract = {Multiple filamentation poses a significant challenge for laser pulse propagation in the atmosphere. The purpose

of this article is to explore how atmospheric turbulence influences the development of modulational instability,

which results in multiple filamentation. We confirm a result that we previously published. We show through

multiple analytical approaches that the growth rate of this instability decreases when the refractive index displays

stochastic behavior},

keywords = {},

pubstate = {published},

tppubtype = {article}

}