Tapered GRIN fiber microsensor

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOThe sensitivity of an optical fiber microsensor based on inter-modal interference can be considerably improved by tapering a short extension of the multimode fiber. In the case of Graded Index fibers with a parabolic refractive index profile, a meridional ray exhibits a sinusoidal path. When these fibers are tapered, the period of the propagated beam decrease down-taper and increase up-taper. We take advantage of this modulation -along with the enhanced overlap between the evanescent field and the external medium- to substantially increase the sensitivity of these devices by tuning the sensor's maximum sensitivity wavelength. Moreover, the extension of this device is reduced by one order of magnitude, making it more propitious for reduced space applications. Numerical and experimental results demonstrate the success and feasibility of this approach.The sensitivity of an optical fiber microsensor based on inter-modal interference can be considerably improved by tapering a short extension of the multimode fiber. In the case of Graded Index fibers with a parabolic refractive index profile, a meridional ray exhibits a sinusoidal path. When these fibers are tapered, the period of the propagated beam decrease down-taper and increase up-taper. We take advantage of this modulation -along with the enhanced overlap between the evanescent field and the external medium- to substantially increase the sensitivity of these devices by tuning the sensor's maximum sensitivity wavelength. Moreover, the extension of this device is reduced by one order of magnitude, making it more propitious for reduced space applications. Numerical and experimental results demonstrate the success and feasibility of this approach.22253043230441FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO2011/01524-8Tam, H.Y., Liu, S.Y., Guan, B.O., Chung, W.H., Chan, T.H., Cheng, L.K., Fiber bragg grating sensors for structural and railway applications (2005) Advanced Sensor Systems and Applications II, 5634, pp. 85-97Villatoro, J., Monzón-Hernández, D., Mejía, E., Fabrication and modeling of uniform-waist single-mode tapered optical fiber sensors (2003) Appl. Opt., 42, pp. 2278-2283Kumar, A., Varshney, R.K., Sa, C., Sharma, P., Transmission characteristics of SMS fiber optic sensor structures (2003) Optics Communications, 219, pp. 215-219Tripathi, S.M., Kumar, A., Varshney, R.K., Kumar, Y.P., Marin, E., Meunier, J.-P., Strain and temperature sensing characteristics of single-mode-multimode-single-mode structures (2009) J. Lightwave Technol., 27, pp. 2348-2356Biazoli, C.R., Silva, S., Franco, M.A.R., Frazão, O., Cordeiro, C.M.B., Multimode interference tapered fiber refractive index sensors (2012) Appl. Opt., 51, pp. 5941-5945Beltrán-Mejía, F., Osório, J.H., Biazoli, C.R., Cordeiro, C.M.B., D-microfibers (2013) J. Lightwave Technol., 31, pp. 2756-2761Wang, P., Brambilla, G., Ding, M., Semenova, Y., Wu, Q., Farrell, G., Investigation of single-mode-multimode-single-mode and single-mode-tapered-multimode-single-mode fiber structures and their application for refractive index sensing (2011) J. Opt. Soc. Am. B, 28, pp. 1180-1186Pillai, R.S., Lorenser, D., Sampson, D.D., Deep-tissue access with confocal fluorescence microendoscopy through hypodermic needles (2011) Opt. Express, 19, pp. 7213-7221Liu, Y., Wei, L., Low-cost high-sensitivity strain and temperature sensing using graded-index multimode fibers (2007) Appl. Opt., 46, pp. 2516-2519(2014) Comsol Multiphysics, , Burlington, MA, USA Version 4.4Ghatak, A., Thyagarajan, K., (1998) An Introduction to Fiber Optics, , Cambridge University Press, chap 9Shiraishi, K., Kuroo, S.-I., A new lensed-fiber configuration employing cascaded GI-fiber chips (2000) J. Lightwave Technol., 18, p. 787Guenther, R.D., (1990) Modern Optics, , Wiley, chap.9Kogelnik, H., On the propagation of gaussian beams of light through lenslike media including those with a loss or gain variation (1965) Appl. Opt, 4, pp. 1562-1569Birks, T., Li, Y., The shape of fiber tapers (1992) J. Lightwave Technol., 10, pp. 432-43

A tutela de direitos por meio de mecanismos de cooperação

Orientador: Manoel Eduardo Alves Camargo e GomesMonografia (graduação) - Universidade Federal do Paraná, Setor de Ciências Jurídicas, Curso de Graduação em DireitoInclui referênciasResumo: O trabalho tem o objetivo incorporar as bases teóricas multidisciplinares da cooperação ao Direito, a partir de uma perspectiva teórica multidisciplinar pouco explorada na área. São apresentadas duas perspectivas para analisar o tema da cooperação: uma simples, utilizando a teoria dos jogos, e outra mais complexa, com modelagem baseada em agentes. O autor propõe uma classificação dos mecanismos de cooperação em simples e complexos e traz exemplos de ambos os tipos. A questão a que se pretende responder se refere à possibilidade de tutela de direitos por meio de mecanismos de cooperação e suas ferramentas, para além do Direito Internacional e da visão principiológica.Abstract: The aim of this work is to incorporate the multidisciplinary theoretical bases of cooperation into the field of law, from a rarely explored multidisciplinary theoretical perspective. Two perspectives are presented for analyzing the topic of cooperation: a simple one, using game theory, and a more complex one, using agent-based modeling. The author proposes a classification of cooperation mechanisms into simple and complex and provides examples of both types. The question being addressed is the possibility of protecting rights through cooperation mechanisms and tools, beyond international law and principled views

Identifying individuals using fNIRS-based cortical connectomes

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORThe fMRI-based functional connectome was shown to be sufficiently unique to allow individual identification (fingerprinting). We aimed to test whether a fNIRS-based connectome could also be used to identify individuals. Forty-four participants performed experimental protocols that consisted of two periods of resting-state interleaved by a cognitive task period. Connectome identification was performed for all possible pairwise combinations of the three periods. The influence of hemodynamic global variation was tested using global signal regression and principal component analysis. High identification accuracies well-above chance level (2.3%) were observed overall, being particularly high (93%) to the oxyhemoglobin signal between resting conditions. Our results suggest that fNIRS is a suitable technique to assess connectome fingerprints.10628892897FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORSem informaçãoSem informaçãoSem informaçã

Integrated polarizers based on tapered highly birefringent photonic crystal fibers

COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFINANCIADORA DE ESTUDOS E PROJETOS - FINEPThis paper proposes and demonstrates the creation of sections with a high polarization dependent loss (PDL) in a commercial highly birefringent (polarization maintaining) photonic crystal fiber (PCF), via tapering with pressure applied to the holes. The tapers had a 1-cm-long uniform section with a 66% scale reduction, in which the original microstructure aspect ratio was kept by the pressure application. The resulting waveguides show polarizing action across the entire tested wavelength range, 1510-1600 nm, with a peak PDL of 35.3 dB/cm (c.f. ∼1 dB/cm for a typical commercial polarizing fiber). The resulting structure, as well as its production, is extremely simple, and enable a small section with a high PDL to be obtained in a polarization maintaining PCF, meaning that the polarization axes in the polarizing and polarization maintaining sections are automatically aligned. © 2014 Optical Society of America.This paper proposes and demonstrates the creation of sections with a high polarization dependent loss (PDL) in a commercial highly birefringent (polarization maintaining) photonic crystal fiber (PCF), via tapering with pressure applied to the holes. The tapers had a 1-cm-long uniform section with a 66% scale reduction, in which the original microstructure aspect ratio was kept by the pressure application. The resulting waveguides show polarizing action across the entire tested wavelength range, 1510-1600 nm, with a peak PDL of 35.3 dB/cm (c.f. similar to 1 dB/cm for a typical commercial polarizing fiber). The resulting structure, as well as its production, is extremely simple, and enable a small section with a high PDL to be obtained in a polarization maintaining PCF, meaning that the polarization axes in the polarizing and polarization maintaining sections are automatically aligned.22151776917775COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFINANCIADORA DE ESTUDOS E PROJETOS - FINEPCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFINANCIADORA DE ESTUDOS E PROJETOS - FINEPSem informaçãoSem informaçãoSem informação0.1.06.1177.00Chraplyvy, A.R., High-capacity lightwave transmission experiments (1999) Bell Labs Tech. J., 4 (1), pp. 230-245Bock, W.J., Chen, J., Eftimov, T., Urbanczyk, W., A photonic crystal fiber sensor for pressure measurements (2006) IEEE Trans. Instrum. Meas., 55 (4), pp. 1119-1123Bergh, R.A., Lefevre, H.C., Shaw, H.J., An overview of fiber-optic gyroscopes (1984) J. Lightwave Technol., 2 (2), pp. 91-107Jacobsen, W., Mayfield, J., Fournier, P., Bolte, D., Elmaola, H., Wang, C.H., Drenzek, G., Soufiane, A., (2013) Single-polarization Fiber, , Verrillon Inc., US Patent 8, 369, 672 B2Nolan, D.A., Berkey, G.E., Li, M.J., Chen, X., Wood, W.A., Zenteno, L.A., Single-polarization fiber with a high extinction ratio (2004) Opt. Lett., 29 (16), pp. 1855-1857Russell, P., Photonic crystal fibers (2006) J. Lightwave Technol., 24 (12), pp. 4729-4749Saitoh, K., Koshiba, M., Single-polarization single-mode photonic crystal fibers (2003) IEEE Photon. Technol. Lett., 15 (10), pp. 1384-1386Ju, J., Jin, W., Demokan, M.S., Design of single-polarization single-mode photonic crystal fiber at 1.30 and 1.55 μm (2006) J. Lightwave Technol., 24 (2), pp. 825-830Zhang, F., Zhang, M., Liu, X., Ye, P., Design of wideband single-polarization single-mode photonic crystal fiber (2007) J. Lightwave Technol., 25 (5), pp. 1184-1189Chen, M.Y., Sun, B., Zhang, Y.K., Broadband single-polarization operation in square-lattice photonic crystal fibers (2010) J. Lightwave Technol., 28 (10), pp. 1443-1446Serrão, V.A., Franco, M.A.R., A new approach to obtain single-polarization hollow-core photonic bandgap fiber (2013) Proc. SPIE 8794, Fifth European Workshop on Optical Fibre Sensors, 879428Kubota, H., Kawanishi, S., Koyanagi, S., Tanaka, M., Yamaguchi, S., Absolutely single polarization photonic crystal fiber (2004) IEEE Photon. Technol. Lett., 16 (1), pp. 182-184Statkiewicz-Barabach, G., Olszewski, J., Napiorkowski, M., Golojuch, G., Martynkien, T., Tarnowski, K., Urbanczyk, W., Thienpont, H., Polarizing photonic crystal fiber with lowindex inclusion in the core (2010) J. Opt., 12 (7), p. 075402Zheng, X., Liu, Y., Wang, Z., Han, T., Tai, B., Tunable single-polarization single mode photonic crystal fiber based on liquid infiltrating (2011) IEEE Photon. Technol. Lett., 23, pp. 709-711Espinel, A.V.Y., Franco, M.A.R., Cordeiro, C.M.B., Tunable single-polarization single-mode microstructure polymer optical fiber (2011) J. Lightwave Technol., 29 (16), pp. 2372-2378Qian, W., Zhao, C.L., Wang, Y., Chan, C.C., Liu, S., Jin, W., Partially liquid-filled hollow-core photonic crystal fiber polarizer (2011) Opt. Lett., 36 (16), pp. 3296-3298Sodré Jr., A.C., Nascimento Jr., A.R., Franco, M.A.R., Oliveira, I., Serrão, V.A., Fragnito, H.L., Numerical and experimental analysis of polarization properties from hybrid PCFs across different photonic bandgaps (2012) Opt. Fiber Technol., 18 (6), pp. 462-469Romagnoli, P., Biazoli, C.R., Franco, M.A.R., Cordeiro, C.M.B., De Matos, C.J.S., Generation of polarizing sections in highly birefringent photonic crystal fibers via post-processing (2013) CLEO:2013, , Optical Society of America, paper JTu4A.12Birks, T.A., Li, Y.W., The shape of fiber tapers (1992) J. Lightwave Technol., 10 (4), pp. 432-438Ju, J., Jin, W., Yang, Y., Introduction of birefringence into photonic crystal fibers (2011) Proc. SPIE 7753, 21st International Conference on Optical Fiber Sensors, 77536JMalitson, I.H., Interspecimen comparison of the refractive index of fused silica (1965) J. Opt. Soc. Am., 55 (10), pp. 1205-1209Gerosa, R.M., Spadoti, D.H., Menezes, L.S., De Matos, C.J.S., In-fiber modal Mach-Zehnder interferometer based on the locally post-processed core of a photonic crystal fiber (2011) Opt. Express, 19 (4), pp. 3124-3129The authors thank CAPES, Mackpesquisa, INCT Fotonicom (CNPq and FAPESP) and FINEP (SIA Project- proc. 0.1.06.1177.00) for financial support

Avaliação do desempenho físico, monitoramento da carga interna de treinamento e da tolerância ao estresse de corredores velocistas durante o período preparatório geral

O objetivo do estudo foi avaliar o desempenho físico e monitorar a carga interna de treinamento (CIT) e a tolerância ao estresse (TE) de corredores velocistas durante o período preparatório geral de treinamento. Seis velocistas de 100 e 400 m do sexo masculino realizaram testes físicos antes e depois de quatro semanas de treinamento: salto vertical e horizontal, Running-Based Anaerobic Sprint Test (RAST) e performance de 100 e 400m. Após cada sessão de treinamento a CIT foi monitorada pelo método da percepção subjetiva de esforço da sessão (PSEsessão) e a TE foi avaliada semanalmente pelo Daily Analysis of Life Demands in Athletes (DALDA). Os resultados demonstraram uma melhora significante no desempenho do salto horizontal após o período de treinamento. Além disso, verificou-se um aumento de 3,1±5,6 % da potência anaeróbia mínima (PAnmín) e uma redução de -15,9±18 % e -12,9±13,6 %, respectivamente no índice de fadiga absoluto e no índice de fadiga relativo obtidos no teste RAST. A CIT demonstrou uma diferença significante na semana 1 em relação as demais semanas; para os escores do DALDA não foram observadas diferenças significantes. Portanto, conclui-se que o período preparatório geral de treinamento levou a uma melhora significante no teste de salto horizontal e impactou de maneira positiva na redução dos índices de fadiga do teste RAST. Além disso, a CIT da semana 1 foi significantemente maior quando comparada às semanas 2 e 3 e a os valores de TE não foram diferentes durante as semanas monitoradas

Assessing atypical brain functional connectivity development : an approach based on generative adversarial networks

Generative Adversarial Networks (GANs) are promising analytical tools in machine learning applications. Characterizing atypical neurodevelopmental processes might be useful in establishing diagnostic and prognostic biomarkers of psychiatric disorders. In this article, we investigate the potential of GANs models combined with functional connectivity (FC) measures to build a predictive neurotypicality score 3-years after scanning. We used a ROI-to-ROI analysis of resting-state functional magnetic resonance imaging (fMRI) data from a community-based cohort of children and adolescents (377 neurotypical and 126 atypical participants). Models were trained on data from neurotypical participants, capturing their sample variability of FC. The discriminator subnetwork of each GAN model discriminated between the learned neurotypical functional connectivity pattern and atypical or unrelated patterns. Discriminator models were combined in ensembles, improving discrimination performance. Explanations for the model’s predictions are provided using the LIME (Local Interpretable Model-Agnostic) algorithm and local hubs are identified in light of these explanations. Our findings suggest this approach is a promising strategy to build potential biomarkers based on functional connectivity