INSTITUTO DE PESQUISAS ENERGÉTICAS E NUCLEARES
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Navegação Eventos - Resumos por Agências de fomento "Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)"

Navegação Eventos - Resumos por Agências de fomento "Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)"

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  • IPEN-DOC 24936

    LIMA, CASSIO ; ZEZELL, DENISE . Discrimination of healthy skin and cutaneous malignant lesions using FTIR spectra and their second derivatives: a comparative study. In: CLINICAL AND TRANSLATIONAL BIOPHOTONICS, April 3-6, 2018, Hollywood, Florida, United States. Resumo expandido... Washington, DC, USA: OSA, 2018.

    Abstract: PC-LDA statistical method was used to differentiate cutaneous tumor tissue from healthy skin. Discrimination accuracy obtained by raw FTIR spectra was 95% and by second derivatives 92%, besides identifying secondary structure of proteins and collagen.

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  • IPEN-DOC 25602

    CASTRO, PEDRO A.A. de ; ZEZELL, DENISE M. . Discrimination of ionizing radiation effects on bone using Fourier Transform Infrared Spectroscopy using K-means. In: BIOPHOTONICS CONGRESS: BIOMEDICAL OPTICS, April 3-6, 2018, Hollywood, Florida, USA. Resumo expandido... Washington, DC, USA: OSA, 2018.

    Abstract: We demonstrated the feasibility of using ATR-FTIR spectroscopy associated with k-means clustering to evaluate the recognition of different doses. Our results open up new possibilities for protein monitoring relating to dose responses.

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  • IPEN-DOC 25611

    DIAS, DERLY A. ; PEREIRA, DAISA L. ; GOMES, GABRIELA V. ; SUGAHARA, VANESSA M.L. ; ZAMATARO, CLAUDIA B. ; ZEZELL, DENISE M. ; MATHOR, MONICA B. . Effects of gamma irradiation on bovine bone microhardness and molecular structure. In: ENCONTRO DE OUTONO, 41., 06-11 de maio, 2018, Foz do Iguaçu, PR. Resumo... São Paulo: Sociedade Brasileira de Física, 2018. p. 1-1.

    Abstract: The skeletal systems is a complex mixed compounds, organic and inorganic, that should present a mechanical resistance to perform functions as protection of the vital organs and load distribution. Gamma radiation is an ionizing radiation that comes from radioative sources or X-ray generator and it is commonly used in health establishments such as radio diagnostic exams, radiotherapy and sterilization of allograft. The characterization of the irradiated bone tissue can be an important tool in the study of the components that are aÆected and how much each dose of ionizing radiation can alter its mechanical properties. This information will be very important in in vitro and ex vivo studies where sterilization of the bone material is necessary and may still be useful in understanding the eÆects on the bone tissue of patients undergoing short-term radiotherapy. For this, 110 samples of bovine femur diaphysis were randomized into 11 groups: G1- untreated (control); G2 to G11 were submitted to gamma irradiation (60Co Gammacel). Samples were polished before irradiation and submitted to a Knoop Microhardness Test to determine the hardness of bovine bone and Fourier transform Infrared spectroscopy (FTIR). Spectra were collected in the midinfrared range in Attenuated Total Reflectance (ATR) sampling mode associated whit PCA multivariate technique to evaluate the molecular changes in bone matrix. The microhardness analysis did not present a significant statistical diÆerence between the irradiated and control groups, showing that ionizing radiation did not aÆect the mechanical structure of the samples, on a micro scale. The results of FTIR with the PCA technique were eÆective in separating all groups, especially those irradiated with doses of 0.002 kGy, 10 kGy and 35 kGy. We conclude that ATR-FTIR spectroscopy associated with PCA is a good method to evaluate the biochemical changes promoted by ionizing radiation in bone matrix. It was observed that hardness was not altered by gamma irradiation and FTIR spectroscopy associated with PCA is a good method to analyze the changes in bone tissue submitted to ionizing radiation.

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  • IPEN-DOC 30151

    OLIVEIRA, RAPHAEL A.M.P. de; TRINDADE, FABIANE J.; FLORIO, DANIEL Z. de; FONSECA, FABIO C. ; ESPOSITO, VINCENZO; FERLAUTO, ANDRE S.. Effects of La content in ceria-lanthana thin films prepared by pulsed laser deposition. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 810-810.

    Abstract: Solid oxide electrochemical reactors are a promising alternative for challenging chemical reactions, such as oxidative coupling of methane (OCM)[1], which convert methane to C2+products. Cerium oxide is a commonly studied oxide membrane material for its high ionic conductivity in the temperature range ideal for conversion reactions (600-900°C), particularly when doped with rare earth cations like Gd, Sm, or La. Recent studies have shown La2Ce2O7as a promising OCM catalyst[2]. This study investigates the structural properties of LaxCe(1-x)O2(1-x/2)thin films, prepared using pulsed laser deposition, with varying stoichiometry. XRD results indicate textured film growth with preferential [100] orientation of cubic crystalline fluorite for low La content (x≤0.5), while x>0.5 had a random orientation. La doping expanded the fluorite structure, increasing lattice parameters from 5.42 Å for x=0 to 5.69 Å for x=0.7. UV-Raman spectroscopy showed that La content x=10 caused a more pronounced balance between Ce4+and Ce3+than pure ceria samples. Impedance revealed a direct relationship between La content and resistance, indicating lower resistance with lower La content. These findings could lead to using Ce-La oxides thin films as catalysts for OCM in electrochemical reactors based on ceria.

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  • IPEN-DOC 29595

    SAULA, MATHEUS S.N.; FELINTO, MARIA C.F.C. ; NUNES, LUIZ A.O.; MALTA, OSCAR L.; BRITO, HERMI F.. Europium activator ion acting as an efficient luminescent probe to identify local symmetry in Li2ZnSn3O8:Eu3+ materials prepared by the MASS method. In: SILVA, FERNANDO de C. da (Org.) REUNIAO ANUAL DA SBQ, 45., 31 de maio - 3 de junho, 2022, Maceió, AL. Resumo... São Carlos, SP: Aptor Software, 2022. p. 390-390.

    Abstract: Luminescent materials doped with rare earth ions (RE) have been intensely applied in several areas in the new photonic technologies, such as emergency lights, radiation detectors, biological markers, and anti-counterfeiting products. Stannate-based host matrices have attracted significant attention, as they are relatively inexpensive and have a favorable bandgap to allow the persistence luminescence phenomenon. In this work, Li2ZnSn3O8:Eu3+ was synthesized by the microwave-assisted solid-state method (MASS) using a domestic microwave oven after gridding Li2CO3, ZnO, SnO2, Eu2O3 precursor oxides. Therefore, the as-prepared precursors were heated in a static air atmosphere at a preset configuration of 900W for 20 min. The material was characterized by powder X-ray diffraction (PXRD), scan electron microscopy (SEM), and diffused reflectance spectroscopy. The PXRD patterns indicate the formation of the desired Li2ZnSn3O8matrix phase when doped with different concentrations of the Eu3+ ion, showing a high crystallinity. The photoluminescence properties were determined based on the emission spectra of the Li2ZnSn3O8:mol%Eu3+ materials (Fig 1), showing intense yellowish-orange and reddish-orange emission colors under UV excitation at 282 and 336 nm, respectively. Moreover, both spectra show narrow emission bands characteristic of 5D0 →7F0-4 Eu3+ transitions. Sinceeuropium ions are powerful spectroscopic probes for the symmetry of the first coordination sphere of these ions in a lattice, and the spectral profiles change with the incident radiation wavelengths, which demonstrates the presence of more than one site of symmetry around the chemical environment of the Eu3+ion.Finally, it is noteworthy that these luminescent materials can be selectively excited in the UV range, leading to more than one specific emission spectral profile, which can be applied as efficient luminescent probes for anti-counterfeiting products.

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  • IPEN-DOC 29574

    DEL-VALLE, MATHEUS ; CARVALHO, MARCELO; SANTOS, MOISES ; PINTO, NATHALI; JATENE, FABIO; POMERANTZEFF, PABLO; BRANDAO, CARLOS; ZEZELL, DENISE . Evaluation of calcified mitral valves after Er,Cr:YSGG irradiation using Optical Coherence Tomography. In: INTERNATIONAL CONFERENCE ON LASER APPLICATIONS IN LIFE SCIENCES, 16th, April 1-2, 2022, Nancy, France. Abstract... Nancy, France: PROGEPI, 2022. p. 152-152.

    Abstract: Mitral valve is responsible to control the left atrium-ventricle blood flux. Mitral stenosis is a disease that occurs in consequence of calcification and fibrosis on the cuspids of the valve. Diagnosis can be performed using echocardiography.Many treatments are possible, and one of them is commissurotomy (surgical approach).High intensity laser irradiation may be a new strategy for this surgical technique[1], and the optical coherence tomography (OCT) may contribute to the valve evaluation[2], asit provides higherspatialresolutionin exchange of lower penetrationthan ultrasonography. In this way, the aim of this study is to evaluate laser irradiation effectsincalcified mitral valvesusing OCTand digital processing.To that, it was conducted an ex-vivostudywith four human mitral valvessamples,obtained from valve replacement surgeries in the Heart Institute.The samples were splitin four groups: scalpel cut, laser cut, scalpel debridement and laser debridement.Cutting and debridement procedures were performed in calcified regions of the valves, usinga disposable scalpelbladeand anEr,Cr:YSGG laser(Waterlase; Biolase Inc., CA, USA), emitting at 2780 nm. The laser parameters were set at power = 1.6W, frequency = 20 Hz, energy density = 28.3J/cm2,pulse duration = 700 μs, 15% of water and 15% of air.The imaging was performed using a spectraldomain OCT system(Callisto110C1;ThorLabs Inc., NJ, USA).It was acquired10 B-scans per sample, 5 inprocedures regions and 5 in sound regions. The Optical Attenuation Coefficient (OAC) was calculated by comparing a beer-lambert like equation to exponential fittings of the A-scans[3].The distribution and normality of variances were tested using Shapiro-Wilk test,and statistical comparison was performed using one-way ANOVA and Tukey’s post hoc. All tests considered a level of significance of 5%.The FigureAshows a representative B-scan of a visibly calcified region, where a pattern of higher intensities can be observed.Thispattern is related tomorphological and optical changes, mainly a refractive index change, due to calcium presence in the valve tissue.This B-scan was acquired only to understand the calcified tissue aspect, as the procedures regions does notpresent visibly largecalcium stones.The Figure Bshowsthe statisticalanalysis, where the sound OAC values, as a mean of all sound regions, presented a significant statistical difference in comparison to scalpel groups, while no difference waspresentedin relation to laser groups. Higher OAC values are related to anaugmentation of the light backscatteringdue to calcium refractive index, leading to a change of lightpropagation in tissue-calcium interfaces.This finding indicates thatthe laser procedures promoted a better removal of calcified tissue than the scalpelmethods, which can be related to tissue-ablation interaction.Furthermore, the statistical difference between scalpel cut group and both laser groups suggests that the scalpel needs more wear interaction with the tissue, such as in the debridement procedure, being unable to significatively remove the calcification in a single cut.This study points the Er,Cr:YSGG and the OCT as potential techniques for the calcified tissue removal and evaluation,respectively, duringmitral valvessurgeries, although further studieswith higher sample numbermust be performed.

    Palavras-Chave: cardiovascular system; valves; cardiovascular diseases; fibrosis; tomography; coherent radiation

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  • IPEN-DOC 25922

    GUEDES, ANDERSON G.; LANDULFO, EDUARDO ; HOELZEMANN, JUDITH; LOPES, FABIO J.S. ; SILVA, MARCOS P.A.; SANTOS, RENATA S.S.; GUERRERO-RASCADO, JUAN L.; ALADOS-ARBOLEDAS, LUCAS; DUARTE, EDICLE S.F.. Evaluation of the transport of atmospheric Sahara dust on Natal-RN through the LIDAR technique of depolarization. In: INTERNATIONAL WORKSHOP ON SAND/DUSTSTORMS AND ASSOCIATED DUSTFALL, 9th, May 22-24, 2018, Tenerife, Spain. Abstract... 2018. p. 249-249.

    Abstract: The objective of this work is describe some results of the Natal LIDAR system (DUSTER), an integrating station of The Latin America Lidar Network (LALINET), aimed to detect and evaluate the transcontinental transport of Sahara dust (SD) to the Brazilian territory during the aerosol MOnitoring campaign Long-­‐range Transportation OVer Natal I (MOLOTOV I) which occurred from December 2016 to February 2017. The city of Natal is located in northeastern Brazil and is one of the continental points closest to the African continent, a important fact to observe the entry of SD in the South American continent. The DUSTER system allows the detection of signals at wavelengths of 355 nm, 532 nm (parallel), 532 nm (perpendicular) and 1064 nm. To detect and characterize SD aerosols and other particles in the atmosphere, DUSTER uses the ability of suspended aerosol particles to change the polarization state of light. The data retrieved by DUSTER allow calculate fundamental parameters in the characterization of atmospheric aerosols such as linear volume depolarization ratio (𝛿!) and particle linear depolarization ratio (𝛿!). Campaign data showed that on a few days the value of 𝛿! varied between 0.09 and 0.33 at a transport altitude within the range of 1-­‐3.3 km above sea level indicating in some cases probably a mixture of SD with other types of aerosols such as marine particles, anthropogenic pollution or biomass burning smoke. The data obtained with DUSTER have allowed verify the seasonality of this transport, the altitudes of detected particles and study its optical properties.

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  • IPEN-DOC 25612

    TEIXEIRA, LUCIA R.C. ; CARVALHO, MARIANA T.; GOMES, ANDERSON S.L.; ZEZELL, DENISE M. ; AMARAL, MARCELLO M.. Evaluation of vascular lesions on cutaneous and mucosa tissue in head and neck regions by Doppler Optical Coherence Tomography. In: ENCONTRO DE OUTONO, 41., 06-11 de maio, 2018, Foz do Iguaçu, PR. Resumo... São Paulo: Sociedade Brasileira de Física, 2018. p. 1-1.

    Abstract: Vascular lesions are one of the most common congenital and neonatal abnormalities, 60% of the cases affect the head and neck region. In most cases these lesions involute spontaneously with no consequences for the patient health, although complications caused by tissue deformities occur in 10%. The proper diagnosis of the different lesions type has impact on the proper choice of patient treatment. The Optical Coherence Tomography (OCT) technique obtains non-invasive real-time cross-section images of tissue structures with high resolution (ª 5μm), about 20 times greater than ultrasound. One of the characteristics of vascular lesions are the presence of blood vessels on the superficial layer of the skin, not present on normal tissue. Using the so-called Doppler OCT it is possible to identify the presence of blood flow and vessels on OCT images. The aim of this work was to evaluate the differences in the architecture of blood vessels in different types of lesions on cutaneous and mucosa tissue in head and neck regions by Optical Coherence Tomography and Doppler Optical Coherence Tomography. After approved by the Ethics Committee of IMIP (protocol no. 728.993), 27 patient lesions were imaged using a Doppler-OCT system (OCS1300SS; Thorlabs GmBH), at 1325 nm of central wavelength and 100 nm of bandwidth. Using the ImageJ software, the average diameter and mean depth of the blood vessels were measured. The average diameter and mean depth of the blood vessels were respectively equal to 114μm ± 92μm and 304.3μm ± 99μm on vascular malformation, 38.6μm ± 19μm and 297.8μm ± 132μm on skin hemangiomas, 45μm ± 16μm and 520.5μm ± 189.5μm on oral mucosa hemangioma (lips), 157.5μm ± 90μm and 695μm ± 136μm on lip lymphatic malformation, and 128μm ± 63μm and 689μm ± 217μm on lip vascular malformation. Using the flow information provided by Doppler OCT, it was possible to evaluate the differences on each lesion type. It was possible to obtain a diagnosis method to differentiate each vascular lesion on skin and oral mucosa, providing information for the early stage treatment of the lesions which will evolute.

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  • IPEN-DOC 23247

    RABELO, J.S. ; ANA, P.A.; MAZZOCCHI, V.L. ; VALERIO, M.E.G.; ZEZELL, D.M. . FTIR and XRD characterization of heat effect on nanostructured synthetic hydroxyapatite and dental enamel. In: INTERNATIONAL CONFERENCE OF NANOPHOTONICS, 10th, July 02-05, 2017, Recife, PE. Abstract... 2017. p. 55-55.

    Abstract: Nanometer sized HAP and dental enamel powders were evaluated regarding changes in their degree of crystallinity and composition after oven or Er,Cr:YSGG laser heating. Decrease of the Ca/P ratio to levels close to the theoretical ones for both synthetic nano-HAp and for the enamel was measured. Laser irradiation caused considerable decrease in the amount of carbonate in the materials heated to high temperatures, but without changes in crystallographic phase.

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  • IPEN-DOC 29573

    ZEZELL, DENISE ; CASTRO, PEDRO ; DEL-VALLE, MATHEUS ; CAMILLO-SILVA, CARLOS ; SAMAD, RICARDO ; DE ROSSI, WAGNER ; SANTOS, MOISES . FTIR imaging on glass substrates evaluation of histological skin burn injuries specimens treated by femtosecond laser pulses. In: INTERNATIONAL CONFERENCE ON LASER APPLICATIONS IN LIFE SCIENCES, 16th, April 1-2, 2022, Nancy, France. Abstract... Nancy, France: PROGEPI, 2022. p. 205-205.

    Abstract: Burn injuries continue to be one of the leading causes of unintentional death and injury in low- and middle-income countries [1]. Burns are considered an important public health problem, because in addition to physical problems that can lead the patient to death, they cause psychological and social damage. An estimated 180,000 deaths every year are caused by burns [2]. The use of infrared (IR) spectroscopy for studying biological specimens is nowadays a wide and active area of research. The IR microspectroscopy has proved to be an ideal tool for investigating the biochemical composition of biological samples at the microscopic scale, as well as its fast, sensitive, and label-free nature [3]. IR image spectral histopathology has shown great promise as an important diagnostic tool, with the potential to complement current pathological methods, reducing subjectivity in biopsy samples analysis. However, the use of IR transmissive substrates which are both fragile and prohibitively very expensive, hinder the clinical translation. The goal of this study is to evaluate the potential of discriminating healing process, in burned skin specimens treated with ultrashort pulses laser 3 days after the burn. This study is considering a previous paper [4], in which it analyzed only micro-ATR-FTIR spectra of a frozen sample point. The specimens were obtained from third degree burn wound. The wounds treatment were performed three days after the burn, and the animals were sacrificed 3 and 14 days post-treatment. Using coverslipped H&E stained tissue on glass from previous histopathological analysis and applying the analytical techniques PCA and K-means on N−H, O−H, and C−H stretching regions occurring at 2500−3800 cm−1 (high wavenumber region), were possible to discriminate burned epidermal and dermal regions from irradiated in same regions on sample. In the figures is shown the average spectrum at (a) day 3 and (b) day 14. , in both there were increase of burned+laser treated bands. The great potential of this study was to analyse coverslipped H&E stained tissue on glass, without compromising the histopathologist practices and contribute for clinical translation.

    Palavras-Chave: burns; injuries; animal tissues; infrared spectra; healing; lasers; pulses

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  • IPEN-DOC 25605

    CASTRO, PEDRO ; LIMA, CASSIO ; ZORN, TELMA M.T.; ZEZELL, DENISE M. . FTIR spectroscopy: an optical method to study wound healing process. In: LATIN AMERICA OPTICS AND PHOTONICS CONFERENCE, November 12-15, 2018, Lima, Peru. Resumo expandido... Washington, DC, USA: OSA, 2018.

    Abstract: In this study, we investigated the ability of Fourier transform infrared spectroscopy to discriminate healthy tissue and thermal injury, aiming the development of an optical method to evaluate the wound healing process.

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  • IPEN-DOC 23457

    ZEZELL, DENISE M. . FTIR spectroscopy for diseases diagnosis. In: ENCONTRO DE FISICA, 03-07 de setembro, 2016, Natal, RN. Abstract... São Paulo: Sociedade Brasileira de Física, 2016.

    Abstract: Mid-infrared spectroscopy is a technique by which the chemical structure of an analyzed material can be identified; it also allows the semi-quantitative analysis of the components of the material. It has been already shown that Fourier transform infrared spectroscopy (FTIR) can be used to evaluate the effects of high-intensity laser irradiation on dentin and enamel tissues,as well as for the study of bone properties and several pathologies, such as lung, thyroid and skin cancer. The structural and biochemical changes associated with the development of enamel caries and also with the interaction of laser irradiation with the enamel, suggest that vibrational spectroscopy are promising techniques to differentiate sound and carious enamel, as well as detect changes due to laser irradiation. Considering that there is no agreement in the literature on the chemical changes promoted by the irradiation of Nd:YAG and Er,Cr:YSGG for preventive purposes on enamel, our studies aimed to determine these changes by FTRaman and FTIR spectroscopy and to investigate the influence of laser irradiation before or after the application of topical fluoride on the development of caries in vitro. Nonmelanoma skin cancers represent 95% of cutaneous neoplasms. Among them, squamous cell carcinoma (SCC) is the more aggressive form and shows a pattern of possible metastatic profile. In this work, we used Fourier transform infrared spectroscopy (FTIR) spectroscopy to assess the biochemical changes in normal skin caused by squamous cell carcinoma induced by multi-stage chemical carcinogenesis in mice. Changes in the absorption intensities and shifts were observed in the vibrational modes associated to proteins, indicating changes in secondary conformation in the neoplastic tissue. Hierarchical cluster analysis was performed to evaluate the potential of the technique to differentiate the spectra of neoplastic and normal skin tissue, so that the accuracy obtained for this classification was 92%. We develop a methodology to interpret hyperspectral imaging data and protein conformational changes observed in nomal thyroid tissue. Raw image datasets were imported into software written in-house in the MATLAB environment and processed to yield pseudo-color images of the tissue sections. All spectra were vector normalized, noisefiltered, and corrected for water-vapour contributions and scattering effects before being subjected to Hierarchical Cluster Analysis (HCA) and correlated with histological structures obtained from images of H&E-stained parallel tissue sections. We successfully identified a protein structural heterogeneity that can be correlated with the spatially resolved amount of iodine in the thyroglobulin structure of colloids and follicular cells. The chemical carcinogens from tobacco are related to over 90% of lung cancers around the world. The risk of death of this kind of cancer is high because the diagnosis usually is made only in advanced stages. Therefore, to develop new diagnostic methods for detecting the lung cancer in earlier is very important stages. The second derivate of spectra indicates that there are displacement in 1646 cm-1 (amine I) and 1255 cm-1 (DNA), allowing the possibility to differentiate the e10 lung normal cells from e10 lung cells transformed by tobacco substances (NKK) with accuracy of 89,9%.

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  • IPEN-DOC 26006

    PEREIRA, DAISA L. ; CASTRO, PEDRO A.A. ; GOMES, GABRIELA V. ; ZAMATARO, CLAUDIA B. ; ZEZELL, DENISE M. ; RIBEIRO, HENRIQUE B.; MATOS, CHRISTIANO J.S.; ANA, PATRICIA A.. Heat-induced depth of Nd:YAG laser irradiation in biological hard tissues. In: ENCONTRO DE OUTONO DA SOCIEDADE BRASILEIRA DE FÍSICA, 42., 26-31 de maio, 2019, Aracaju, SE. Resumo... São Paulo: Sociedade Brasileira de Física, 2019.

    Abstract: Confocal Raman spectroscopy is a non-destructive and non-invasive technique which provides surface Raman spectra and depth images of biological structures contactless with the sample, with no use of ionizing radiation to penetrate in the sample under analysis. These characteristics allow its experimental use without any side e®ects to the sample. The depth images are obtained by Raman microscopy and are related to the characteristics of the tissues. This study aims to characterize irradiated hard tissues and correlate the depth reached by the heat of the laser irradiation with the obtained images. For this, thirty 8 mm2 blocks of bovine enamel and bovine root dentin, were randomized into 6 groups: G1- enamel untreated; G2- enamel irradiated with Nd:YAG micropulsed laser (1064 nm, 10 Hz- Lares Research R°) using a coal paste as photoabsorber; G3- enamel irradiated with Nd:YAG nanopulsed laser (1064 nm, 20 Hz, Brilliant, Quantel Laser) using a coal paste as photoabsorber; G4-G6 (bovine root dentin in the same conditions of treatment of G1-G3). The measurements were performed in three di®erent depth regions of the cubic shaped samples: region A- left corner above of the sample, region B- middle of the sample and Region C- right corner below of the sample. The area under the phosphate, carbonate, amide I, II, and III bands were calculated. The Raman spectra of the Nd:YAG irradiated samples detected a reduction in all the organic components of the enamel after laser irradiation. Previous studies of our group demonstrated that di®erences in carbonate substitution in the apatite lattice are related to the apatite instability and demineralization susceptibility. Considering that carbonate free apatite is less susceptible to acid attack, the results of this study suggest that Nd:YAG lased enamel can be more resistant to caries, in a direct correlation to the thickness of the treated area. It was found that for micropulsed Nd:YAG laser, the heat induced depth was 10 § 2 ¹m and for nanopulsed laser the heat induced depth was 8 § 3 ¹m. So, it is possible to correlate the heat penetration depth of the laser irradiation with the images obtained by the confocal Raman.

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  • IPEN-DOC 23456

    AMARAL, M.M. ; TEIXEIRA, L.R.C. ; CARVALHO, M.T.; GOMES, A.S.L.; ZEZELL, D.M. . Hemangioma vascular lesion characterization by optical coherence tomography. In: ENCONTRO DE FISICA, 03-07 de setembro, 2016, Natal, RN. Abstract... São Paulo: Sociedade Brasileira de Física, 2016.

    Abstract: Hemangioma vascular lesions are common childhood tumors appearing mainly in the neck and head. It affects 10% of children worldwide [1]. In most cases the lesions does not bring consequences for the patient's health, although some patient can develop complications caused by tissue deformities. In extreme cases, it could be a life risk. The early diagnosis of the lesion could lead to an early treatment and a reduction on its aesthetic and psychological consequences. In this work, we evaluate the use of the Optical Coherence Tomography to differentiate between hemangioma vascular lesions from normal skin. Using a swept source OCT (9 m and 18 m axial and lateral resolution) 541 images of hemangioma lesion and 50 image of normal skin on the hand region was acquired. IMIP Ethics Committee approved this study (protocol no. 728.993). In order to characterize the normal skin and the hemangioma vascular lesion it was implemented an automated analysis using Matlab ©. Two approaches was implemented, a morphological analysis [2] to evaluate the epidermis thickness and an attenuation coefficient analysis [3] to evaluate the optical feature of the tissue. It was possible to evaluate the depth distribution of epidermis for booth normal skin and hemangioma lesion. Normal skin presented a thicker epidermis layer and a broader distribution, while hemangioma lesion presented a narrower epidermis layer and uniform distribution. The attenuation coefficient of hemangioma lesion presented 9.2% higher values than normal skin. Booth approaches proved to be valid for hemangioma diagnosis and could be complementary to each other and the combination of these approaches will be discussed in this work.

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  • IPEN-DOC 29317

    BORDON, CAMILA D.S.; DIPOLD, JESSICA ; ROSSI, WAGNER de ; FREITAS, ANDERSON Z. ; KASSAB, LUCIANA R.P.; WETTER, NIKLAUS U. . Influence of Ag nanoparticles in waveguides on doped germanate glasses. In: ENCONTRO BRASILEIRO DE ESPECTROSCOPIA RAMAN, 7., 5-8 de dezembro, 2022, São Pedro, SP. Resumo... 2022.

    Abstract: Writing by using femtossecond (fs) laser enables fast prototyping and has low complexity compared to other fabrication methods. For materials that do not allow light confinement and propagation, waveguiding by double-line technology is necessary. Previously, we demonstrated waveguiding in double-lines for undoped germanate and tellurite glasses, as well as GeO2-PbO doped with Er3+/Yb3+ and Nd3+. The results for the Nd3+ glass were promising for the fabrication of integrated amplifiers, lossless components and lasers. This motivated the present investigation, where silver (Ag) nanoparticles (NPs) were added to the Nd3+ doped GeO2-PbO bulk in order to enhance its guiding capabilities. Raman measurements were made with a LabRam HR Evolution - HORIBA, using a 532 nm laser with 100 mW power and a 10 x objective lens with 0.25 NA. An integration time of 1 second and 15 accumulations was used to reduce noise and make the observed peaks clearer. First, the Raman spectrum was measured for the bulk (b) glass (Fig. 1a) and between the written lines (Fig. 1a). There are no substantial changes between these, indicating, as expected, that there are no relevant structural changes in the guiding region between the two lines. However, comparing the bulk region (Fig. 1a) with the inside of the written line with 4 superimposed lines (Fig. 1b), there are major changes in some of the peaks. The peak at 411.2 cm-1 (b) shifted to 433.9 cm-1, indicating modification in the symmetric stretching vibrations of the Ge-O-Ge bonds. The peak at 517.5 cm-1 (b) to 508.1 cm-1 shows changes in the symmetric stretching vibrations along the Ge- O-Ge chain, demonstrating lower density of these bonds in the irradiated region. A slight change of the 782.3 cm-1 and 867.4 cm-1 (b) are also verified, and are related to the Ge-O- and Ge-O-Ge symmetric stretching vibrations in the GeO4 tetrahedral units and asymmetric stretching vibrations of the Ge-O-Ge bonds, respectively. These changes are larger than the ones previously shown for the same material without the Ag NPs, which shows the influence of the nanoparticles during the writing process.

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  • IPEN-DOC 23273

    BONTURIM, E. ; REIS, R. dos; MERIZIO, L.G.; RODRIGUES, L.C.V.; BRITO, H.F.; FELINTO, M.C.F.C. . Investigation of rare earth distribution in Sr2MgSi2O7:Eu2+,Dy3+ nanophosphors prepared by wet-chemical routes. In: INTERNATIONAL CONFERENCE ON LUMINESCENCE, 18th, August 27 - September 1, 2017, João Pessoa, PB. Abstract... 2017.

    Abstract: Luminescent materials have been developed through ne chemistry methods that help to achieve a better control of parameters such as morphology, particle size, atomic homogeneity and high purity single phase in low temperature synthesis.[1, 2] In this work, the material Sr1:98MgSi2O7 nanoparticles doped with 0.01 mol of Eu2+ and codoped with 0.01 mol of Dy3+ was prepared via Pechini and Condensation methods. Post-annealing by microwave assisted method using granular coal as the susceptor/reducing agent [3] was applied on both materials and their luminescent properties were compared. The structural position of Eu2+ used as the activator ions determines photoluminescence properties. The luminescence spectra of Sr2MgSi2O7:Rn+ nanomaterial (R: Eu2+, Dy3+) shows a high emission broad band assigned to the intercon gurational transition 4f65d1 ! 4f7 centered around 460 nm, which is overlapped with a low emission lines attributed to the 4F9=2 ! 6H13=2 transition of Dy3+ ion (Fig. 1b). Elemental mappings obtained by Energy Dispersive X-Ray (EDX) presents dopants more likely to be found at the edge, indicating a possible segregation of rare earths to the grain boundaries during the synthesis (Fig. 1c). The persistent luminescence phenomenon emitting in a blue region was observed for both nanomaterials.

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  • IPEN-DOC 27449

    TEJADA, GRACIELA; GATTI, LUCIANA ; BASSO, LUANA; MARANI, LUCIANO; CASSOL, HENRIQUE; ARAI, EGIDIO; ARAGAO, LUIZ; CRISPIM, STEPHANE; NEVES, RAIANE; DOMINGUES, LUCAS ; CORREIA, CAIO ; IPIA, ALBER; GLOOR, MANUEL; MILLER, JOHN; VON RANDOW, CELSO. Is it feasible to relate CO2 atmospheric measurements with land use and cover change data?: A primary assessment of land use and cover change datasets in the Amazon. In: EGU General Assembly, May 4-8, 2020, Online. Abstract... Göttingen, Germany: Copernicus, 2020.

    Abstract: Atmospheric CO2 concentrations have had a significant increase in recent years reaching levels never seen before. In the Amazon region, the main CO2 emissions come from land use and cover change (LUCC), especially for the deforestation of natural forests. It is very important to understand the impacts of climate change and deforestation on the Amazon forests to understand their role in the current carbon balance at different scales. The lower-troposphere greenhouse gas (GHG) monitoring program “CARBAM project”, has been collecting bimonthly GHGs vertical profiles in four sites of the Amazon since 2010, filling a very important gap in regional GHGs measurements. Here we compare different LUCC datasets for the Amazon region to see if there is a relation between annual LUCC and bimonthly CO2 aircraft measurements in the Amazon. We compared the annual (2010-2018) LUCC area from IBGE, PRODES and mapbiomas pan-amazon datasets for each mean influence area of the CARBAM sites and relate this LUCC areas with the annual CO2 fluxes. We found differences in the classification methods of the LUCC data, showing differences in the total deforested area. The LUCC data have different tendencies in each CARBAM influence area having more deforestation in the east side of the Amazon CARBAM sites. There is no clear trend between LUCC and carbon fluxes in the last 8 years. Inter-annual CO2 fluxes variability could be related with the several droughts that influence the photosynthesis/respiration. Here we highlight the scale issues regarding LUCC datasets, atmospheric CO2 measurements and CO2 modeling to better understand the current Amazon carbon balance.

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  • IPEN-DOC 27960

    TEJADA, GRACIELA; GATTI, LUCIANA V. ; BASSO, LUANA S.; MARANI, LUCIANO; CASSOL, HENRIQUE L.G.; CRISPIM, STEPHANE P.; NEVES, RAIANE A.L.; DOMINGUES, LUCAS G. ; IPIA, ALBER; CORREIA, CAIO S. de C. ; ARAI, EGIDIO; GLOOR, EMANUEL U.; MILLER, JOHN B.; VON RANDOW, CELSO. Land use and cover change and CO2 atmospheric measurements in the Amazon forests. In: AGU CHARPMAN CONFERENCE, August 26-29, 2019, San Diego, CA, USA. Abstract... Washington, DC, USA: American Geophysical Union, 2019.

    Abstract: In the last years, global CO2 concentrations have reach levels never seen before reaching more than 400 ppm. Among the main causes of these emissions are the burning of fossil fuels and the land use and cover change (LUCC) related emissions. In the Amazon region, the main CO2 emissions are related to deforestation. Multitemporal LUCC datasets have been restrict to Brazil, but now has been released a pan-Amazon dataset for all the countries sharing the Amazon, opening the possibility of studying the Amazon forests as a whole. On the other hand, the lower-troposphere greenhouse gas (GHG) monitoring program “Carbam project”, has been collecting biweekly GHGs vertical profiles in four sites of the Amazon since 2010, filling a very important gap in regional GHGs measurements. Our purpose is to understand the relationships between regional LUCC and CO2 aircraft measurements in the Amazon. Here we present the relationships between annual LUCC data from 2010 to 2017 in the Amazon forest and in each mean influence area of Carbam sites comparing them with mean annual CO2 fluxes. Considering the whole Amazon forests and the mean annual CO2 fluxes, the years with more forest loss and agriculture increase are 2010 and 2016, showing relation with CO2 fluxes. On the other hand, 2011 and 2017 also have deforestation (less than 2010 and 2016), but the CO2 fluxes are lower, showing that droughts could also influence the CO2 concentrations. Looking at each influence area, total carbon flux of Alta Floresta and Rio Branco have the same tendency as the forest loss from 2013 to 2017, but no in 2010 and 2012. In Tabantinga, Tefé and Santarem there is no a direct relationship between the carbon fluxes and the forest loss. To understand better the relationships at each site, we have to consider the years of measurements. Also, the temporal scale, carbon fluxes are measure biweekly and the LUCC data is annual. Looking at the potentialities and limitations of this relationship, it will be possible to improve the methodology to better understand the interaction of human activities and CO2 emissions on the carbon balance.

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  • IPEN-DOC 29997

    MENDES, VALERIA ; AZEVEDO, LUCIANE H.; ZEZELL, DENISE M. . Lasers não-ablativos de alta intensidade na apneia obstrutiva do sono. In: RIBEIRO, MARTHA S. (Ed.) FORUM ON-LINE DE TECNOLOGIAS DA LUZ NA SAUDE, 3., 26-28 de maio, 2022, São Paulo, SP. Resumo... 2022. p. 3-3.

    Abstract: INTRODUÇÃO: O ronco primário e apneia grave representam as diferentes gravidades do mesmo distúrbio fisiopatológico, que afeta em torno de um bilhão de pessoas em todo o mundo. É mais frequentemente em homens e idosos. O ruído é causado pela vibração dos tecidos moles na área mais constrita das vias aéreas superiores. As opções terapêuticas usuais apresentam limitações e as publicações em literatura sobre os efeitos clínicos do uso de laser no manejo do ronco e AOS são escassas e pouco exploradas. OBJETIVOS: Após determinar as melhores condições de irradiação, este estudo tem como objetivo, avaliar o tratamento do ronco com irradiação de alta intensidade, sequencial e não-ablativa de dois lasers pulsados: Nd:YAG e Er:YAG (Lightwalker, Fotona). Os resultados obtidos com o tratamento são comparados às condições em linha de base. METODOLOGIA: Um estudo longitudinal, intervencionista e prospectivo está em andamento com a aprovação do comitê de ética em pesquisa. Até o momento, 32 de 40 voluntários que transitam entre ronco primário e apneia obstrutiva do sono moderada foram tratados em três sessões de irradiação laser não-ablativa. O intervalo entre as sessões foi de14 dias. O volume do espaço orofaríngeo foi analisado por registro fotográfico, de acordo com o índice Mallampati modificado. Saturação de oxigênio, gravidade do ronco e qualidade do sono também serão avaliados. RESULTADOS ESPERADOS: O principal resultado clínico obtido será a expansão da luz da via aérea superior pela diminuição da complacência tecidual. Com isso, redução ou eliminação do ronco.

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  • IPEN-DOC 26033

    SILVA, ROGERIO M.V.; BELINATO, WALMIR; SANTOS, WILLIAM S.; PERINI, ANA P. ; NEVES, LUCIO P.; SANTOS, CARLA J.; SOUZA, DIVANIZIA N.. Low cost electron irradiator using 90Sr+90Y sources. In: RUBIO, MARCELO (Ed.); TIRAO, GERMAN (Ed.) INTERNATIONAL SYMPOSIUM ON RADIATION PHYSICS, 14th, October 7-11, 2018, Córdoba, Argentina. Abstract... Córdoba: Centro de Excelencia en Productos y Procesos, 2018. p. 178-178.

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A pesquisa no RD utiliza os recursos de busca da maioria das bases de dados. No entanto algumas dicas podem auxiliar para obter um resultado mais pertinente.

✔ É possível efetuar a busca de um autor ou um termo em todo o RD, por meio do Buscar no Repositório , isto é, o termo solicitado será localizado em qualquer campo do RD. No entanto esse tipo de pesquisa não é recomendada a não ser que se deseje um resultado amplo e generalizado.

✔ A pesquisa apresentará melhor resultado selecionando um dos filtros disponíveis em Navegar

✔ Os filtros disponíveis em Navegar tais como: Coleções, Ano de publicação, Títulos, Assuntos, Autores, Revista, Tipo de publicação são autoexplicativos. O filtro, Autores IPEN apresenta uma relação com os autores vinculados ao IPEN; o ID Autor IPEN diz respeito ao número único de identificação de cada autor constante no RD e sob o qual estão agrupados todos os seus trabalhos independente das variáveis do seu nome; Tipo de acesso diz respeito à acessibilidade do documento, isto é , sujeito as leis de direitos autorais, ID RT apresenta a relação dos relatórios técnicos, restritos para consulta das comunidades indicadas.

A opção Busca avançada utiliza os conectores da lógica boleana, é o melhor recurso para combinar chaves de busca e obter documentos relevantes à sua pesquisa, utilize os filtros apresentados na caixa de seleção para refinar o resultado de busca. Pode-se adicionar vários filtros a uma mesma busca.

Exemplo:

Buscar os artigos apresentados em um evento internacional de 2015, sobre loss of coolant, do autor Maprelian.

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

✔ Para indexação dos documentos é utilizado o Thesaurus do INIS, especializado na área nuclear e utilizado em todos os países membros da International Atomic Energy Agency – IAEA , por esse motivo, utilize os termos de busca de assunto em inglês; isto não exclui a busca livre por palavras, apenas o resultado pode não ser tão relevante ou pertinente.

✔ 95% do RD apresenta o texto completo do documento com livre acesso, para aqueles que apresentam o significa que e o documento está sujeito as leis de direitos autorais, solicita-se nesses casos contatar a Biblioteca do IPEN, bibl@ipen.br .

✔ Ao efetuar a busca por um autor o RD apresentará uma relação de todos os trabalhos depositados no RD. No lado direito da tela são apresentados os coautores com o número de trabalhos produzidos em conjunto bem como os assuntos abordados e os respectivos anos de publicação agrupados.

✔ O RD disponibiliza um quadro estatístico de produtividade, onde é possível visualizar o número dos trabalhos agrupados por tipo de coleção, a medida que estão sendo depositados no RD.

✔ Na página inicial nas referências são sinalizados todos os autores IPEN, ao clicar nesse símbolo será aberta uma nova página correspondente à aquele autor – trata-se da página do pesquisador.

✔ Na página do pesquisador, é possível verificar, as variações do nome, a relação de todos os trabalhos com texto completo bem como um quadro resumo numérico; há links para o Currículo Lattes e o Google Acadêmico ( quando esse for informado).

ATENÇÃO!

ESTE TEXTO "AJUDA" ESTÁ SUJEITO A ATUALIZAÇÕES CONSTANTES, A MEDIDA QUE NOVAS FUNCIONALIDADES E RECURSOS DE BUSCA FOREM SENDO DESENVOLVIDOS PELAS EQUIPES DA BIBLIOTECA E DA INFORMÁTICA.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

1. Portaria IPEN-CNEN/SP nº 387, que estabeleceu os princípios que nortearam a criação do RDI, clique aqui.


2. A experiência do Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP) na criação de um Repositório Digital Institucional – RDI, clique aqui.

O Repositório Digital do IPEN é um equipamento institucional de acesso aberto, criado com o objetivo de reunir, preservar, disponibilizar e conferir maior visibilidade à Produção Científica publicada pelo Instituto, desde sua criação em 1956.

Operando, inicialmente como uma base de dados referencial o Repositório foi disponibilizado na atual plataforma, em junho de 2015. No Repositório está disponível o acesso ao conteúdo digital de artigos de periódicos, eventos, nacionais e internacionais, livros, capítulos, dissertações, teses e relatórios técnicos.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.