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Artigo IPEN-doc 31368 Theoretical analysis of nonlinear polarization in a high-power YDCFL2024 - CARDOSO, ELBIS S.; SAMAD, RICARDO E.; MOTTA, CLAUDIO C.Avstract- This work investigates the influence of temperature, pump power, and upper-level population density on the nonlinear refractive index of a high-power Yb-doped double-cladding fiber laser (YDCFL) operating in the CW regime, in the forward pumping configuration. A theoretical model that examines how these physical variables impact the nonlinear polarization of a ytterbium-doped optical fiber is presented. This phenomenon can result in nonlinear effects in the YDCFL.Artigo IPEN-doc 31367 Theoretical analysis of increasing beam quality by adapting mode field radius at pump-signal combiner’s signal fiber2024 - MENDES, LUCAS S.; NACARATTI, DAVI P.; CARDOSO, ELBIS S.; SAMAD, RICARDO E.High transmission efficiency, low insertion loss, and high beam quality are interesting characteristics of beam combiners. These devices have enabled power coupling in the fiber laser's active medium, and their performance has a strong impact on the fiber laser's efficiency. In this paper, the increase in the optical beam quality M2 was analyzed by adapting the modal radius of the combiner signal fiber. The formulation is supported by the Finite Difference Beam Propagation Method (FD-BPM) and Fast Fourier Transforms (FFT), and they were implemented in Matlab.Artigo IPEN-doc 31366 The role of the student chapter in scientific outreach2024 - PRADO, FELIPE M.; PERES, DANIELLA L.; STASI, RAFFAEL; ANJOS, VINICIUS P. dos; CAVALERO, JULIA G.; ZEZELL, DENISE M.This paper reviews the activities conducted by a student chapter of optics and photonics in Brazil during the 2023–2024 academic year. The initiative played a significant role within its host institution, contributing to scientific outreach and academic enrichment. The paper assesses key initiatives and their impact on both the broader community and the institution itself. We highlight several events organized during this period, which engaged over 1,500 participants. Additionally, the paper examines the benefits derived from these activities for the institutions, the participants, and the general public, emphasizing their contribution to the dissemination of optics and photonics within the community.Artigo IPEN-doc 31365 Synthesis of magneto-plasmonic hybrid AuFe(oxide) nanoparticles and their use as SERS substrates2024 - LASKOWSKI, DANIELLE do R.; ANJOS, VINICIUS P. dos; FEILSTRECKER JUNIOR, SIDO; COSTA, KEVIN S.; MACHADO, THIAGO N.; LENZ, JORGE A.; VIANA, EMILSON R.; GOES, RAFAEL E. de; SCHREINER, WIDO H.; BEZERRA JUNIOR, ARANDI G.Magneto-plasmonics (MP) refers to nanomaterials that simultaneously exhibit plasmonic and magnetic phenomena, typically achieved by combining plasmonic materials like Au, Ag, and Cu with magnetic 3d metals and their oxides. We present experimental results on the laser ablation synthesis in solution (LASiS) of Au-Fe(oxide) core-shell nanoparticles (NP) in water. Our nanoparticles were characterized through UV-Vis spectroscopy, Transmission Electron Microscopy, Dynamic Light Scattering, and Raman spectroscopy. As a proof-of-concept, we successfully used our Au-Fe(oxide) NP as substrates in Surface Enhanced Raman Spectroscopy (SERS) to detect minute amounts of biological molecules like thiourea and urea in aqueous solutions.Artigo IPEN-doc 31364 Red LED radiation as a potential radioprotector using a zebrafish embryo model2024 - GUSMÃO, KARINE R. dos A.; RODRIGUES, MURILO A.V.; YOSHIMURA, TANIA M.; ROGERO, JOSE R.; RIBEIRO, MARTHA S.; FREITAS, ANDERSON Z. deRadiation therapy (RT) is crucial for cancer treatment but often causes severe side effects that impact quality of life, emphasizing the need for better tissue radioprotection strategies. This study investigated the radioprotective potential of red LED irradiation using zebrafish embryos. After determining the median lethal dose of gamma radiation (LD50) to be 16.7 Gy, embryos were exposed to red LED before gamma radiation. While red LED alone did not affect survival rates, pre-treatment with red light increased survival to over 50% after LD50 gamma radiation. These results suggest that red LED could help reduce the acute effects of RT.Artigo IPEN-doc 31244 Rapid identification of breast cancer in different stages using micro-FTIR and supervised machine learning methods2024 - GERMANO, GLEICE; VALLE, MATHEUS D.; PERES, DANIELLA L.P.M. de O.; SILVA, DANIELA de F.T. da; PEREIRA, THIAGO M.; ZEZELL, DENISE M.According to the World Health Organization, breast cancer is the second most common cancer in the world; 11.5% of the total cases of cancer in both genders and 15.4% of deaths in females are reported. Accurate determination of the intrinsic subtype and disease stage of breast cancer will help in the adoption of optimal treatment strategies, thus improving overall outcomes. The aim of the present work, therefore, is to apply micro-FTIR spectroscopy combined with different supervised machine learning methods to classify various types and stages of breast cancer and to identify the chemometric areas that best distinguish between them. In the work reported here, PCA-LDA and PLS-DA models were carried out in the raw data in the fingerprint region (1800–900 cm−1) and the region characteristic for proteins (1750–1400 cm−1). Therefore, the analysis of these results reveals significant differences in the amide I and amide II regions, thus proving that both PCA-LDA and PLS-DA are useful frameworks for performing discrimination analyses.Artigo IPEN-doc 31243 Pump controlled Nd:YVO4 random laser2024 - DIPOLD, JESSICA; KASSAB, LUCIANA R.P.; WETTER, NIKLAUS U.Yttrium vanadate doped with neodymium crystal powder random laser have demonstrated promising results in 1064 nm emission when pumped at a wavelength of 806 nm. In this study, we show that by using a 585 nm pump wavelength, it is possible to achieve random lasing at both 1064 nm and 1340 nm, with the emission tunable through variations in pump intensity.Artigo IPEN-doc 31242 Migration and alignment of fibroblasts2024 - LOPES, FABIO; RODRIGUES, MARIA F.; PASI, FRANCESCA; VIGORITE, MARTINA; NONO, ROSANA; ZEZELL, DENISE M.; SILVA, DANIELA F.T.Although laser radiation is electromagnetic, its electric field polarization is rarely considered in photobiomodulation. This study compared the effects of laser polarization (parallel or perpendicular to the wound axis) with an electric field from a non-laser device on fibroblast migration and alignment. Human dermis fibroblasts were cultured, and a wound was inflicted. Cultures were evaluated under five conditions: parallel electric field(E//), perpendicular electric field(Epp), parallel polarized laser(L//), perpendicular polarized laser(Lpp), and control. All treatments increased cell migration compared to the control. Cells in the L// were more aligned after six hours, and those in the Epp group after 12 hours.Artigo IPEN-doc 31241 Infrared spectroscopy imaging of cardiac atria from mice treated with interleukin-1beta2024 - STASI, RAFFAELE; GERMANO, GLEICE C.M.; SILVA, EVELIN M. da; LIMA, FERNANDO S. de; MORENO-LOIZA, OSCAR J.; MEDEI, EMILIANO H.; ZEZELL, DENISE M.This study explores the application of Fourier-transform infrared (FTIR) spectroscopy imaging to analyze changes in the cardiac atria of mice treated with interleukin-1 beta (IL-1beta), a cytokine known to influence cardiac remodeling. By employing k-means clustering on the spectral data, we identified distinct clusters that differentiate between IL-1beta-treated tissues and controls. The analysis revealed significant spectral differences, particularly in the amide band region, which suggests variations in protein content. These preliminary findings will be expanded into a more thorough investigation of the composition of IL-1beta-treated tissues.Artigo IPEN-doc 31240 Implementation of an imaging system in a spectrometer for laser accelerated electrons2024 - BRANDAO, VITORIA M.C.; SAMAD, RICARDO E.We present here the development of an imaging system for an electron spectrometer aiming at the characterization of laser-accelerated electrons. The spectrometer features a constant magnetic field that deflects electrons, based on their kinetic energy, which hit a scintillator that luminesces; an imaging system captures this luminescence and projects it onto a digital camera outside a vacuum chamber. The imaging system is designed to optimize the collection of the luminescence and to produce a demagnified image on the digital camera. A theoretical and experimental analysis of the lenses foci and positioning is presented, resulting in a final assemblage.Artigo IPEN-doc 31239 Decomposition method to speed up optimization loops containing Monte Carlo simulations to estimate radioisotope production2024 - NUNES, BRUNO S.; BONATTO, ALEXANDRE; SAMAD, RICARDO E.Monte Carlo simulations are an essential tool for modeling radioisotope production through nuclear reactions. However, they can be computationally demanding, especially when running optimization loops that require many simulations. This study addresses this limitation by demonstrating a decrease in computation time over 5 orders of magnitude by decomposing an electron energy spectrum into an orthogonal basis that was Monte Carlo pre-propagated, to estimate radioisotope production from bremsstrahlung induced photo-nuclear reactions. A comparative analysis of fifty electron spectra showed that this method could replicate the results of original spectra simulations with minimal discrepancies, with errors typically below 8%.Artigo IPEN-doc 31238 Comparative analysis of a high-power YDCFL operating in forward and two-end pumping configurations2024 - CARDOSO, ELBIS C.; SAMAD, RICARDO E.; MOTTA, CLAUDIO C.This study compares high-power Yb-doped double-cladding fiber lasers (YDCFLs) operating in forward and two-end pumping configurations. The temperature profile, changes in the nonlinear refractive index, thermal power density, and nonlinear polarization were analyzed under these pumping conditions. The results indicate that the bidirectional configuration provides superior thermal stability, while the unidirectional configuration is more susceptible to nonlinear effects.Artigo IPEN-doc 31237 Combined effects of optical therapy and stem cells for tendon rehabilitation2024 - SAUTER, ISMAEL P.; YOSHIMURA, TANIA M.; RAPOSO, BRUNO L.; RIBEIRO, MARTHA S.Tendon injuries often fail to fully regenerate after surgery, leading to impaired function and possible graft rejection. Advances in regenerative medicine include tendon engineering with stem cells. Herein, we demonstrate that adipose-derived mesenchymal stem cells respond differently to culture media, and red LED enhances metabolism and collagen synthesis.Artigo IPEN-doc 31236 ATR-FTIR spectroscopy in the detection of amoxicillin2024 - ANJOS, VINICIUS P. dos; MARANGONI, CAROLINE G.P. da S.; GOES, RAFAEL E. de; BEZERRA JUNIOR, ARANDI G.; ZEZELL, DENISE M.Amoxicillin is still one of the most common antibiotics to treat bacterial infections. Although conventional drug monitoring techniques often exhibit significant limitations in terms of accuracy and analysis speed, optical-based methods can be introduced as an appealing option for this purpose. Fourier transform infrared spectroscopy (FTIR) has been long established and implemented across various fields, including biomedical, clinical, and pharmaceutical. This work presents an alternative approach to the usual amoxicillin detection and monitoring procedures using vibrational spectroscopy. In this preliminary investigation, our results show several characteristics for quantification, with limit of detection of 93 µM, point to the high potential of the technique for drug monitoring.Artigo IPEN-doc 31235 Antibiotic monitoring employing raman/SERS spectroscopy2024 - ANJOS, VINICIUS P.; MARANGONI, CAROLINE G.P. da S.; DALLA-COSTA, LIBERA M.; BEZERRA JUNIOR, ARANDI G.; ZEZELL, DENISE M.; GOES, RAFAREL E. deRapid and accurate detection of antibiotics is a critical challenge in the healthcare field, but a new approach based on Raman/SERS spectroscopy could be a solution. This research uses this technique to present the acquisition of spectra (“fingerprints”) of vancomycin, little explored in the scientific literature, and ciprofloxacin antibiotics. The analyses allowed understanding how the nanoparticles (Au, Ag and Cu) can influence the SERS spectrum acquisition of each antibiotic. The results showed that the Raman spectroscopy technique can provide unique spectra for each type of antibiotic evaluated, allowing for their precise identification.Artigo IPEN-doc 31234 Analysis of the nonlinear refractive Index in a high-power YDCFL using the RK4 method2024 - CARDOSO, ELBIS S.; NACARATTI, DAVI P.; SAMAD, RICARDO E.; MOTTA, CLAUDIO C.This work presents an analysis of the variation of the nonlinear refractive index in a high-power Yb-doped double-cladding fiber laser (YDCFL) induced by the pump power. The RK4 numerical method was employed to solve the ordinary differential equation describing the behavior of the pump power in the YDCFL operating in a continuous wave (CW) forward configuration. As a result, the nonlinear refractive index behavior along the longitudinal direction of the optical fiber was obtained.Artigo IPEN-doc 31233 A deep neural network approach for oral squamous cell carcinoma identification2024 - PERES, DANIELLA L.; GERMANO, GLEICE; SILVA, DANIELA F.T.; BACHMANN, LUCIANO; MATOS, LEANDRO L. de; FELIPE, JOAQUIM C.; PEREIRA, THIAGO M.; ZEZELL, DENISE M.Early detection and diagnosis of oral squamous cell carcinoma (OSCC) are essential for improving patient outcomes. This study presents the development of a deep neural network model trained to classify OSCC using hyperspectral FTIR spectroscopy imaging. The network's performance was evaluated using accuracy, precision, recall, and F1-score metrics. The model demonstrated high effectiveness in classifying unfolded OSCC hyperspectral images, showing potential as a valuable tool for supporting diagnostic processes in clinical settings.Artigo IPEN-doc 31232 24 mJ single pulse energy from a Nd:YLF/Cr:YAG laser in a DBMC configuration2024 - PRADO, FELIPE M.; FRANCO, TOMAS J.; WETTER, NIKLAUS U.This work presents a high-power Nd:YLF/Cr:YAG laser in a Double Beam Mode Controlling configuration, achieving a single pulse energy of 24 mJ, with a pulse duration of 15 ns, emitting at 1053 nm. The configuration demonstrated significant improvements in beam quality, with measured M² values of 2.13 vertically and 2.42 horizontally when compared to single-pass configurations. These results highlight the effectiveness of the DBMC approach in enhancing beam quality while maintaining high energy output.Artigo IPEN-doc 31225 Estudo comparativo da biocompatibilidade após tratamento de superfície com plasma kinpen IND® em amostras de policaprolactona (PCL)2024 - GOMES, A.P.G.; DRIGO, E.; TADA, D.; CRUZ, N.C.; BOCK, E.G.P.Artigo IPEN-doc 31217 Sensitivity estimation for the future laser ionization diagnosis in inferring neutral particle density in the TCABR tokamak2024 - ALBUQUERQUE, FERNANDO A.F.; WETTER, NIKLAUS U.; SEVERO, JOSE H.This study undertakes an estimation of photoionization occurrences and the ensuing reduction in hydrogen spectral line intensities via Laser-Induced Ionization. The objective is to quantify the sensitivity of the neutral particle density diagnostic