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URI Permanente para esta coleçãohttps://repositorio.ipen.br/handle/123456789/8931

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SEIRA Enhancement of Amoxicillin Detection Using Laser- Generated Gold Nanoparticles
2025 - ANJOS, VINICIUS P.; SILVA, DANIELA de F.T. da; LASKOWSKI, DANIELLE do R.; BEZERRA JUNIOR, ARANDI G.; ZEZELL, DENISE M.
This research demonstrates SEIRA-based detection of Amoxicillin using AuNP as an enhancing substrate. The approach boosts FTIR sensitivity, enabling precise molecular characterization. This method holds promise for pharmaceutical analysis and trace-level antibiotic.
Mathematical Method for Enhancing Biochemical information in Micro-FTIR Images of Histopathological Slides
2025 - PEREIRA, T.M.; ALMEIDA, E.S.; PERES, D.L.; SILVA, D.F.T.; GERMANO, G.; ZEZELL, D.M.; BACHMANN, L.
Early and accurate cancer diagnosis improves prognosis and reduces treatment invasiveness and costs. Histopathological biopsy analysis is crucial but depends on pathologist expertise. Biochemical information from samples can enable earlier diagnosis due to tissue changes before visible alterations. Optical techniques, particularly micro-infrared spectroscopy (micro-FTIR), are promising for this. However, artifacts from contaminants and baseline distortions can affect data quality. This work develops a method using principal component regression (PCR) to remove these artifacts. Applying this method to 192 micro-FTIR images of thyroid and mouth tissues achieved over 90% correlation with traditional hematoxylin-eosin images, indicating effective artifact removal and accurate results.
Histopathological Analysis of Fine-Needle Aspiration Biopsies of Thyroid Nodules Using Explainable Convolutional Neural Networks
2024 - BAFFA, MATHEUS de F.O.; BACHMANN, LUCIANO; PEREIRA, THIAGO M.; ZEZELL, DENISE M.; SOARES, EDSON G.; PADUA, JOEL D.B.; FELIPE, JOAQUIM C.
Thyroid Cancer is a disease in which abnormal cells grow uncontrollably in the gland with the potential to invade other organs. Every year, almost 44,000 new cases are diagnosed worldwide. Histopathological diagnosis of fine-needle aspiration biopsies of thyroid nodules is the most precise exam to confirm the diagnosis and estimate the stages of the disease. The diagnostic process in such an exam involves detecting atypical signs, such as the presence of cell proliferation with irregular shape and texture. This task could be even harder once you consider that most thyroid biopsies might present multiple pathological states, such as inflammatory diseases and hyperplasia. Therefore, this paper addresses the development of a Computer Vision method to assist the histopathological diagnosis of normal, thyroid papillary carcinoma and goiter. The proposed method model and implement a Convolutional Neural Network to detect visual patterns to differentiate the three pathological states. Experiments following the Holdout Cross-Validation protocol reached an accuracy of 88.73% for the multiclass approach and 95.74% accuracy for the binary assessment. The results confirm the potential of the proposed method to assist pathologists in prescribing a more precise diagnosis.
Diagnosys of Oral Cancer Using FTIR Hyperspectral Images and Linear Discriminant Analysis
2025 - PERES, DANIELLA L.; SILVA, DANIELA de F.T. da; PEREIRA, THIAGO M.; MATOS, LEANDRO L. de; ZEZELL, DENISE M.
This study used FTIR hyperspectral imaging (HSI) and LDA to classify 48 OSCC and 48 healthy tissue samples, achieving 85% accuracy. These results show that HSI with LDA can aid early OSCC detection.
Fan-out, fiber-coupled, focal-plane array of detectors for Laser Ionization Diagnosis in the TCABR Tokamak and validation of plasma density models
WETTER, NIKLAUS U.; ALBUQUERQUE, FERNANDO A.F.; SEVERO, JOSE H.F.; CANAL, GUSTAVO P.
Brazil's Ministry of Science, Technology, and Innovation is launching a National Program for Nuclear Fusion, including the construction of a National Fusion Laboratory. The program features an advanced Laser Ionization Diagnosis system for accurate plasma neutral density measurement.
A linear discriminant analysis for Interleukin-1 beta effects on the vibrational spectroscopy of heart tissue
2025 - STASI, RAFFAELE; MORENO-LOIZA, OSCAR J.; SILVA, DANIELA F.T.; ANJOS, VINICIUS P.; SILVA, EVELIN M. da; MEDEI, EMILIANO H.; ZEZELL, DENISE M.
Fourier-transform infrared (FTIR) spectroscopy imaging was used to analyze cardiac atria from IL-1β-treated mice. Linear discriminant analysis identified spectral differences, notably in the 1500–1800 cm−1 region, suggesting IL-1β alters protein and lipid composition in heart tissue.
Salivary ATR-FTIR signatures for obstructive sleep apnea
2025 - MENDES, VALERIA; ANJOS, VINICIUS P.; SILVA, DANIELA de F. T. da; ZEZELL, DENISE M.
This review investigates salivary ATR-FTIR spectral signatures as diagnostic and monitoring tools for Obstructive Sleep Apnea (OSA). The study not only reinforces previous findings but also consistently identifies key vibrational peaks (2962, 1643, 1546/1448, 1076, 1662 cm-1). These results validate the proposed pre-analytical procedures for biofluid sample preparation, ensuring spectral reliability and demonstrating the effectiveness of this methodology in capturing salivary “molecular fingerprints” associated with OSA.
Identifying inflammatory signatures in heart tissue via FTIR and linear discriminant mapping
2025 - STASI, RAFFAELE; SILVA, DANIELA F.T.; ANJOS, VINICIUS P.; MEDEI, EMILIANO H.; ZEZELL, DENISE M.
Fourier-transform infrared (FTIR) imaging spectroscopy was used to investigate biochemical alterations in cardiac tissue samples treated with Interleukin-1beta (IL-1β). Linear Discriminant Analysis (LDA) was applied to spectra in the 1500–1800 cm−1 region. In this work, the LDA component score for each pixel was plotted as a heatmap, enabling spatial visualization of spectral alterations. Heatmaps were generated for each of the three control and three treated samples. Additionally, the LDA loading curves show the induced alterations across wavenumbers.
Curved waveguide irradiated by femtosecond laser in Ag-doped GeO2–PbO glasses for photonic applications
2025 - FERNANDES, THIAGO V.; BORDON, CAMILA D.S.; WETTER, NIKLAUS U.; ROSSI, WAGNER de; KASSAB, LUCIANA R.P.
We demonstrate the fabrication of straight and curved dual waveguides in GeO2-PbO glasses embedded with silver nanoparticles using femtosecond laser inscription. This research includes evaluating beam quality, propagation loss, and polarization of the double-wall waveguides.
Comparative analysis of transverse mode instability in single-clad and double-clad fibers
2025 - CARDOSO, ELBIS S.; SAMAD, RICARDO E.; MOTTA, CLAUDIO C.
This work presents a comparative study between single-clad (SCF) and double-clad (DCF) fiber designs, focusing on modal propagation and tolerance to the transverse mode instability (TMI). Analytical solutions for LPmn modes and numerical simulations are used to analyze the transverse intensity distributions and the influence of structural parameters on the TMI onset threshold in high-power fiber lasers. Results show that DCFs exhibit greater tolerance to TMI, attributed to the broader transverse mode distribution in lower-index regions, which enhances optical confinement and thermal dissipation.
Comparison of soil samples with different clay, sand, and silt contents using speckle interferometry
2025 - PRADO, FELIPE M.; FAULIM, GUSTAVO D.C.; ZAMARIOLLI, LUIS F.R.; SOUZA, PEDRO M. de; WETTER, NIKLAUS U.; SILVA, SIDNEY L. da
This study contrasts the Speckle intensity curves of soil samples with clay and sand. The technique used was Speckle interferometry and the analysis was the computational method based on the Time History Speckle Pattern, THSP, and Error Theory.
Adaptive optics systems
2025 - MORAIS, PAULO J.D. de; SILVA, RUBENS C. da; ROSSI, WAGNER de; MOTTA, CLAUDIO C.
This paper presents the implementation of a Lagrange-based processor extension for woofer-tweeter adaptive optics control. The approach leverages the complementary response of two deformable mirrors to compensate for a broad range of wavefront aberrations. Applications include high-energy laser propagation through the atmosphere, where adaptive optics mitigate distortions caused by turbulence, enabling improved beam focus and reduced scintillation in scenarios such as freespace optical communication and energy transmission.
The multichannel approach within the NUMEN project
2025 - CARBONE, DIANA; AGODI, CLEMENTINA; BELLONE, JESSICA; CAPPUZZELLO, FRANCESCO; CAVALLARO, MANUELA; COLONNA, MARIA; GREGORIO, GIOVANNI de; FERREIRA, JONAS L.; GARGANO, ANGELA; LENSKE, HORST; SGOUROS, ONOUFRIOS; SPATAFORA, ALESSANDRO; ACOSTA, LUIS; AMADOR-VALENZUELA, PAULINA; BRISCHETTO, GIUSEPPE; CALVO, DANIELA; CHAVEZ LOMELI, EFRAIN R.; CIRALDO, IRENE; DEALUNAY, FRANCK; DJAPO, HARIS; EKE, CANEL; FINOCCHIARO, PAOLO; FISICHELLA, MARIA; FIRAT, SUNA; GUAZZELLI, MARCILEI A.; HACISALIHOGLU, AYLIN; LAY, JOSE A.; LINARES, ROBERTO; LUBIAN, JESUS; MEDINA, NILBERTO H.; MORALLES, MAURICIO; OLIVEIRA, JOSE R.B.; PAKOU, ATHENA; PANDOLA, LUCIANO; PETRASCU, HORIA; SOLAKCI, SELCUK O.; SOUKERAS, VASILEIOS; SOULIOTIS, GEORGIOS; TORRESI, DOMENICO; TUDISCO, SALVATORE; YILDIRIM, AYDIN; ZAGATTO, VINICIUS A.B.
Different reactions channels induced by the 18O + 40Ca collisions at 275 MeV incident energy are analysed within a a multichannel approach. Experimental data from many reactions are simultaneously measured and a consistent analysis is performed with the same reaction and structure frameworks. The results are part of the NUMEN project. In particular, the elastic and inelastic scattering, one- and two-proton transfer, one-neutron transfer, and single charge exchange reactions are explored. The experimental data are well described by the theoretical calculations, performed by including microscopic nuclear structure inputs.
Chemometric evaluation of ampicillin stability using FTIR spectroscopy and multivariate techniques
2025 - ANJOS, VINICIUS P.; FREIRE, MARIA R.V.B.; STASI, RAFFAELE; SILVA, DANIELA de F.T. da; ZEZELL, DENISE M.
Antibiotic quality has always been a concern in the pharmaceutical industry and the World Health Organization (WHO), especially in the growing and emerging antimicrobial resistance crisis. FTIR spectroscopy can contribute to the monitoring of antimicrobials, especially when coupled with chemometric techniques. The present work aims to investigate spectral differences of Ampicillin samples through FTIR qualitatively and quantitatively, highlighting the spectral differences associated with different degradation conditions (acidic and thermal).
Theoretical investigation of transverse mode instability in Yb-DCFs due to thermally-induced modal coupling
2025 - CARDOSO, ELBIS S.; SAMAD, RICARDO E.; MOTTA, CLAUDIO C.
This paper presents a theoretical investigation of the transverse mode instability (TMI) threshold in Yb-doped doubleclad fibers (Yb-DCFs). The analysis is based on the semi-weak guiding approximation, applied to the LP01 and LP13 modes. The thermally-induced modal coupling is modeled using coupled differential equations, and the TMI threshold is analytically estimated as a function of the fiber core diameter. Results show that, above the critical threshold, power transfer occurs between modes, highlighting the importance of thermal and modal modeling in the design of more stable fibers for high-power applications.
Laser Ablation in Liquids as a Versatile Approach for the Synthesis of Hybrid Nanoparticles with Plasmonic and Magneto-Plasmonic SERS Applications
2025 - LASKOWSKI, DANIELLE; FEILSTRECKER JUNIOR, SIDO; ANJOS, VINICIUS P.; COSTA, KEVIN S.; MACHADO, THIAGO N.; LENZ, JORGE; VIANA, EMILSON R.; GOES, RAFAEL E. de; SCHREINER, WIDO H.; BEZERRA JUNIOR, ARANDI G.
The synthesis of nanomaterials with tunable optical and magnetic properties is essential for applications in nanomedicine, sensing, and bioimaging. This work explores Laser Ablation in Liquid (LASiS) as a clean and efficient method for producing hybrid nanoparticles for use as SERS (Surface-Enhanced Raman Spectroscopy) substrates. We synthesize and characterize two types of hybrid nanoparticles: metallic Au-Ag alloys and core-shell Au-Fe(oxide) structures. The study demonstrates how LASiS enables the engineering of nanomaterials with enhanced properties for electric field amplification in vibrational spectroscopy, highlighting its potential as a versatile tool for nanobiophotonics applications through a unified experimental approach.
Discriminating oral squamous cell carcinoma via µFTIR spectroscopy imaging and tree-based models
2025 - 2025 - PERES, DANIELLA L.; SILVA, DANIELA T. da; FELIPE, JOAQUIM C.; CORREA, LUCIANA; MATOS, LEANDRO L. de; PEREIRA, THIAGO M.; ZEZELL, DENISE M.
This study evaluates the classification of oral squamous cell carcinoma (OSCC) using micro-FTIR hyperspectral imaging and two tree-based models: Random Forest and XGBoost. After preprocessing and PCA, class imbalance was addressed with AllKNN and Tomek Links. Both models achieved high accuracy, and key spectral bands-Amide I, II, and III-were consistently highlighted, supporting their relevance in oral cancer detection.
Impact of sampling strategies on the classification of micro-FTIR hyperspectral data
2025 - PERES, DANIELLA L.; SILVA, DANIELA T.; FELIPE, JOAQUIM C.; CORREA, LUCIANA; MATOS, LEANDRO L. de; MENEZES, MARIO O. de; PEREIRA, THIAGO M.; ZEZELL, DENISE M.
This study evaluated class balancing strategies for classifying oral squamous cell carcinoma (OSCC) in FTIR hyperspectral images using the XGBoost model. Although the dataset was balanced at the image level, spectral quality filtering introduced pixel-level class imbalance. Resampling methods— SMOTE, Tomek Links, and their combination—were tested, as well as AllKNN for redundancy reduction. All approaches outperformed the unbalanced baseline, but the best overall performance metrics were achieved with the combined use of AllKNN and Tomek Links.
AND, OR, and XNOR optical logic gates via pixel-wise modulation with spatial light modulators and 4f system
2025 - PRADO, FELIPE M.; SILVA, SIDNEY L. da; WETTER, NIKLAUS U.
We present a simple optical setup based on two cascaded reflective phase-only spatial light modulators in a 4f configuration to perform basic logic operations in parallel. By adjusting polarization states and encoding binary input patterns as phase masks, we implemented three logic gates (AND, OR, and XNOR) with results consistent with the expected truth tables. The modulation relies on polarizing components to allow pixel-wise control across the entire image. Experimental results show good agreement with the target amplitude distributions and expected results.
ReLU-like nonlinear activation from an Nd:YVO random laser
2025 - PRADO, FELIPE M.; DIPOLD, JESSICA; WETTER, NIKLAUS U.
This work shows a ReLU-like activation function generated by the emission of a Nd:YVO random laser. The emission response was fitted and implemented as a custom activation function in a neural network trained on the MNIST dataset, achieving an accuracy of 96%. This indicates the potential of random lasers as optical activations for future optical neural network architectures.

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