Direct Determination of Sugar Cane Quality Parameters by X-ray Spectrometry and Multivariate Analysis

Current methods for quality control of sugar cane are performed in extracted juice using several methodologies, often requiring appreciable time and chemicals (eventually toxic), making the methods not green and expensive. The present study proposes the use of X-ray spectrometry together with chemometric methods as an innovative and alternative technique for determining sugar cane quality parameters, specifically sucrose concentration, POL, and fiber content. Measurements in stem, leaf, and juice were performed, and those applied directly in stem provided the best results. Prediction models for sugar cane stem determinations with a single 60 s irradiation using portable X-ray fluorescence equipment allows estimating the % sucrose, % fiber, and POL simultaneously. Average relative deviations in the prediction step of around 8% are acceptable if considering that field measurements were done. These results may indicate the best period to cut a particular crop as well as for evaluating the quality of sugar cane for the sugar and alcohol industries.Fapesp [2011_05860-2]FAPESPCNPqCNP

Natural radiation levels in powdered milk samples Níveis de radioatividade natural em amostras de leite em pó

The control and monitoring of radioactive elements in foodstuffs is fundamental for human health maintenance. This work presents procedures to measure radioactivity levels in powdered milk samples and also a brief discussion of radionuclide transference from the environment to mankind. The measurements were performed utilizing a high-resolution gamma-ray spectrometer using an HPGe detector. The results allowed the quantification of 40K, 137Cs and 208Tl radionuclides. For 40K the average activity was 482 ± 37 Bq/kg and for 137Cs and 208Tl the lower level of detection was, respectively, 3.7 ± 1.1 and 0.5 ± 0.2 (Bq/kg). The results obtained for the milk samples were compared to data found in the literature and to the limits established by the Brazilian National Commission of Nuclear Energy (CNEN) to assure its safety to human consuption.A medida de traços radioativos, no ambiente e em elimentos, é de fundamental importância para o monitoramento dos níveis de radiação a que o homem està exposto, direta ou indiretamente. Este trabalho consiste na medida de traços radioativos em leite em pó, através da espectrometria gama de alta resolução. Foi possível identificar os radionuclídeos 40K, 137Cs e 232Th (obtido do 208Tl) com as respectivas atividades médias, em Bq/Kg, 482 ± 37, 5,1 - 11,2 and 1,6 - 3,7. Os resultados foram comparados com os limites estabelecidos pela Comissão Nacional de Energia Nuclear (CNEN), apresentando níveis normais para os leites analisados, podendo ser consumido sem restrições

^{<span style="font-size:17.0pt;mso-bidi-font-size:10.0pt;font-family:"Times New Roman","serif"; mso-bidi-font-weight:bold">40</span>}<span style="font-size:21.5pt; mso-bidi-font-size:14.5pt;font-family:"Arial","sans-serif";mso-bidi-font-weight: bold">K<span style="font-size:22.0pt;mso-bidi-font-size:15.0pt; font-family:"Times New Roman","serif"">, ^{<span style="font-size: 17.0pt;mso-bidi-font-size:10.0pt;font-family:"Times New Roman","serif"; mso-bidi-font-weight:bold">137</span>}<span style="font-size:21.5pt; mso-bidi-font-size:14.5pt;font-family:"Arial","sans-serif";mso-bidi-font-weight: bold">C <span style="font-size:22.0pt;mso-bidi-font-size:15.0pt; font-family:"Times New Roman","serif";mso-bidi-font-weight:bold">san<span style="font-size:21.5pt;mso-bidi-font-size:14.5pt;font-family:"Arial","sans-serif"; mso-bidi-font-weight:bold">d ^{<span style="font-size:17.0pt; mso-bidi-font-size:10.0pt;font-family:"Times New Roman","serif";mso-bidi-font-weight: bold">232</span>}<span style="font-size:21.5pt;mso-bidi-font-size:14.5pt; font-family:"Arial","sans-serif";mso-bidi-font-weight:bold">Th <span style="font-size:22.0pt;mso-bidi-font-size:15.0pt;font-family:"Times New Roman","serif"; mso-bidi-font-weight:bold">ac<span style="font-size:20.5pt;mso-bidi-font-size: 13.5pt;font-family:"Arial","sans-serif";mso-bidi-font-weight:bold">tivitiesin<span style="font-size:22.0pt;mso-bidi-font-size:15.0pt;font-family:"Times New Roman","serif"; mso-bidi-font-weight:bold"> <span style="font-size:21.5pt;mso-bidi-font-size: 14.5pt;font-family:"Arial","sans-serif";mso-bidi-font-weight:bold">B<span style="font-size:22.0pt;mso-bidi-font-size:15.0pt;font-family:"Times New Roman","serif"; mso-bidi-font-weight:bold">razilian mi<span style="font-size:21.5pt; mso-bidi-font-size:14.5pt;font-family:"Arial","sans-serif";mso-bidi-font-weight: bold">lk <span style="font-size:22.0pt;mso-bidi-font-size:15.0pt; font-family:"Times New Roman","serif";mso-bidi-font-weight:bold">samp<span style="font-size:21.5pt;mso-bidi-font-size:14.5pt;font-family:"Arial","sans-serif"; mso-bidi-font-weight:bold">I<span style="font-size:22.0pt;mso-bidi-font-size: 15.0pt;font-family:"Times New Roman","serif";mso-bidi-font-weight:bold">es measured by gamma ray spectrometry </span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>

5-11<span style="font-size: 15.0pt;mso-bidi-font-size:8.0pt;font-family:" times="" new="" roman","serif""="">This work deals with the measurement of radioactivity in powdered milk. with high-resolution gamma-ray spectrometry, using a HPGe detector. Preliminary measurements were accomplished to define the kind of the system shield, the geometry of the sample recipient, the size of the sampling and the self-absorption correction. <span style="font-size:15.0pt;mso-bidi-font-size: 8.0pt;font-family:" arial","sans-serif""="">It <span style="font-size:15.0pt; mso-bidi-font-size:8.0pt;font-family:" times="" new="" roman","serif""="">was possible to measure the radionuclides <span style="font-size:12.5pt;mso-bidi-font-size: 5.5pt;font-family:" times="" new="" roman","serif""="">40K, <span style="font-size:12.5pt;mso-bidi-font-size:5.5pt;font-family: " times="" new="" roman","serif""="">137<span style="font-size:15.0pt; mso-bidi-font-size:8.0pt;font-family:" times="" new="" roman","serif""="">Cs and 232Th. Tukey's average comparison test was used to check the repeatability of the measurements. </span

Direct Determination of Sugar Cane Quality Parameters by X-ray Spectrometry and Multivariate Analysis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Current methods for quality control of sugar cane are performed in extracted juice using several methodologies, often requiring appreciable time and chemicals (eventually toxic), making the methods not green and expensive. The present study proposes the use of X-ray spectrometry together with chemometric methods as an innovative and alternative technique for determining sugar cane quality parameters, specifically sucrose concentration, POL, and fiber content. Measurements in stem, leaf, and juice were performed, and those applied directly in stem provided the best results. Prediction models for sugar cane stem determinations with a single 60 s irradiation using portable X-ray fluorescence equipment allows estimating the % sucrose, % fiber, and POL simultaneously. Average relative deviations in the prediction step of around 8% are acceptable if considering that field measurements were done. These results may indicate the best period to cut a particular crop as well as for evaluating the quality of sugar cane for the sugar and alcohol industries.60431075510761Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Improved prediction of soil properties with multi-target stacked generalisation on EDXRF spectra

Energy dispersive X-ray fluorescence (EDXRF) is one of the most quick, environmentally friendly and least expensive spectroscopic analytical methodologies for assessing soil quality parameters. However, challenges in EDXRF spectral data analysis still demand more efficient methods. One possible solution is using Machine Learning (ML), particularly Multi-target Regression (MTR) methods, which predict multiple parameters taking advantage of inter-correlated parameters. In this study, we proposed the Multi-target Stacked Generalisation (MTSG), a novel MTR method relying on learning from different regressors in stacking structure for a boosted outcome. We compared MTSG and 5 MTR methods for predicting 10 parameters of soil fertility. Random Forest and Support Vector Regression (SVR) were used as learning algorithms embedded into each MTR method. Results showed the superiority of MTR methods over the Single-target Regression (the traditional ML method), reducing the predictive error for 5 parameters. Particularly, MTSG obtained the lowest error for phosphorus, total organic carbon and cation exchange capacity. When observing the relative performance of SVR with a radial kernel, the prediction of base saturation percentage was improved by 19%. Finally, the proposed method was able to reduce the average error from 0.67 (single-target) to 0.64 analysing all targets, representing a global improvement of 4.48%

Avaliação do controle do Bipolaris maydis no capim Zuri com diferentes tratamentos.

O Bipolaris maydis é um fungo que causa manchas foliares e, não havendo controle, pode evoluir para a morte da planta. O capim Panicum maximum cv. BRS Zuri é um capim indicado para sistemas intensivos de produção de carne e leite bovino, devido ao seu alto potencial produtivo. Também foi lançado com a informação de que tem alto grau de resistência à mancha das folhas, causada pelo B. maydis. Contudo, foram observadas áreas de BRS Zuri com sintomas de B. maydis em Tocantins e no Pará. Assim, este trabalho objetivou avaliar o efeito de diferentes tratamentos na sintomatologia causada pelo fungo