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•Identification of goat milk adulteration by adding cow milk.•A miniaturized NIR spectrometer is used for the in-situ analysis.•NIR spectroscopy coupled with different preprocessing ...techniques and PLS algorithms.•Classification models by OC-PLS, PLS-DA and iSPA-PLS-DA were compared.•iSPA-PLS-DA achieved the best accuracy, sensitivity and specificity rates.
This work aimed at the use of a miniaturized near-infrared (NIR) spectrophotometer for the in-situ goat milk authentication in terms of its adulteration by adding cow milk. For this, One-Class Partial Least Squares (OC-PLS), PLS for Discriminant Analysis (PLS-DA), and the Successive Projections Algorithm for interval selection in PLS-DA (iSPA-PLS-DA) were employed. OC-PLS misclassified 1 pure goat milk sample as adulterated and 49 adulterated sample as pure in the test set, while PLS-DA misclassified 1 adulterated sample as pure goat milk and 2 pure goat milk samples as adulterated in the test set. On the other hand, the best predictive ability was achieved by iSPA-PLS-DA when using the spectra pre-processed with smoothing by 7-point window moving mean and baseline offset correction, classifying correctly 100% of the pure goat milk samples and misclassifying only one adulterated sample in the test set. This result reinforces the fact of the selection of intervals by SPA provided a more parsimonious model, with less latent variables than the other models, since it selects only the most relevant and interpretable chemical information. Therefore, the proposed methodology represents a promise, non-destructive, fast, and low-cost tool for screening the authentication of raw goat milk, also helping to support future decisions by the regulatory agencies to prevent this kind of fraud directly in the production local.
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•A chemometrics-assisted color histogram-based system used for green food analysis.•Digital image-based fingerprint signatures used as analytical information.•Identification of goat ...milk adulteration by adding cow milk.•One-class classification models by OC-PLS and DD-SIMCA were compared.•RGB/DD-SIMCA model had the highest sensitivity specificity and efficiency rates.
This work used a chemometrics-assisted color histogram-based analytical system (CACHAS) as a low-cost alternative analytical tool for the authentication of goat milk in terms of its adulteration with cow milk. For this fingerprint signatures using Grayscale RGB (red–greenblue) and HSI (hue-saturation-intensity) histograms were explored as analytical information. Then One-Class Partial Least Squares (OC-PLS) and Data-Driven Soft Independent Modeling of Class Analogy (DD-SIMCA) were employed as one-class classifiers. The best result was obtained by the RGB/DD-SIMCA model correctly classifying all pure goat milk and adulterated samples in the test set. This differentiation is favored by the presence of carotenoids in cow milk having a slightly yellowish color while goats convert β-carotene to retinol. Thus considering the complexity of the raw materials and the accessibility of the developed methodology the proposed CACHAS method stands advantageously out by finding the principles of green food analysis for screening the authenticity of goat milk.
Using color histograms and SPA-LDA to classify bacteria de Almeida, Valber Elias; da Costa, Gean Bezerra; de Sousa Fernandes, David Douglas ...
Analytical and bioanalytical chemistry,
09/2014, Letnik:
406, Številka:
24
Journal Article
Recenzirano
In this work, a new approach is proposed to verify the differentiating characteristics of five bacteria (
Escherichia coli
,
Enterococcus faecalis
,
Streptococcus salivarius
,
Streptococcus oralis
, ...and
Staphylococcus aureus
) by using digital images obtained with a simple webcam and variable selection by the Successive Projections Algorithm associated with Linear Discriminant Analysis (SPA-LDA). In this sense, color histograms in the red–green–blue (RGB), hue-saturation-value (HSV), and grayscale channels and their combinations were used as input data, and statistically evaluated by using different multivariate classifiers (Soft Independent Modeling by Class Analogy (SIMCA), Principal Component Analysis-Linear Discriminant Analysis (PCA-LDA), Partial Least Squares Discriminant Analysis (PLS-DA) and Successive Projections Algorithm-Linear Discriminant Analysis (SPA-LDA)). The bacteria strains were cultivated in a nutritive blood agar base layer for 24 h by following the Brazilian Pharmacopoeia, maintaining the status of cell growth and the nature of nutrient solutions under the same conditions. The best result in classification was obtained by using RGB and SPA-LDA, which reached 94 and 100 % of classification accuracy in the training and test sets, respectively. This result is extremely positive from the viewpoint of routine clinical analyses, because it avoids bacterial identification based on phenotypic identification of the causative organism using Gram staining, culture, and biochemical proofs. Therefore, the proposed method presents inherent advantages, promoting a simpler, faster, and low-cost alternative for bacterial identification.
Figure
Summary of the new proposed methodology for bacteria classification by using color histograms and SPA-LDA
O Estado do Maranhão registra altos índices de desmatamento e focos de queimadas, especialmente nas regiões sul e sudeste, onde os biomas Cerrado e Amazônico estão presentes. Diante desse contexto, ...destaca-se o município de Amarante, localizado na região sul do estado, que abriga o segundo maior rebanho de gado e desempenha um papel significativo como polo agropecuário. Além disso, o município está integrado à Fronteira Econômica do MATOPIBA. O presente estudo tem como objetivo analisar o uso e cobertura da terra e sua relação com o fogo nas Terras Indígenas do Município de Amarante, Maranhão, Brasil. Utilizando técnicas de sensoriamento remoto e análise de dados geoespaciais, busca-se investigar os padrões de desmatamento, fragmentação florestal e ocorrência de incêndios nessas terras indígenas. Por meio de uma abordagem temporal, analisando o período de 1985 a 2020 com intervalos de 5 anos entre cada recorte, foram obtidos resultados que revelam uma correlação direta entre o avanço das atividades agropecuárias, a frequência de queimadas, o desmatamento e a exploração ilegal de madeira na região. O estudo também destaca o aumento da violência e dos conflitos territoriais decorrentes da expansão dessas atividades econômicas, afetando diretamente as populações indígenas e evidenciando a tensão territorial relacionada ao uso e cobertura da terra. Diante dessas constatações, ressalta-se a urgente necessidade de implementar estratégias de conservação e manejo sustentável do uso da terra nas áreas indígenas, visando à proteção da biodiversidade e dos modos de vida tradicionais.
In the midst of the pandemic caused by the new coronavirus (SARS-CoV-2), researchers and governmental and non-governmental institutions are mobilizing to implement strategies to face cases of ...COVID-19. Aim: This study aimed to map the triage strategies for cases of COVID-19, with the purpose of identifying sources in the literature that make it possible to explore the understanding of the strategies in different contexts. A scope review was conducted with searches in the CINAHL Database, PubMed, LILACS and hand-search, considering studies carried out with users of health services and documents published by governmental and non-governmental institutions, between the years 2019 and 2020, resulting in 40 articles for full reading. To explore the key concept, thematic analysis was carried out at two levels: (1) triage strategies, (2) forms and experiences of triage. Five triage strategies were mapped: health services triage; digital triage by remote use of technologies; community triage; home visit triage and airport and port triage. The forms and experiences of mapped triages involved risk classification, diagnosis and definition of conducts or combined. The use of strategies with remote technological resources stands out, as well as the adaptation of existing scales with simple algorithms as a tendency.
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•SCBA is a viable precursor for alkali-activated materials.•The main mechanism of reaction of SCBA pastes is the diffusion process, independent of paste formulation.•The compressive ...strength and microstructure are strongly dependent of alkalis and silicate content.•There is no relation between the heat flow and accumulated heat with compressive strength of SCBA pastes.
The production of Portland cement exhibits significant importance for social and economic development of a country, however also generates environmental impacts from the extraction of raw materials to the production of clinker. Despite the impacts, the demand for Portland cement is still growing in developing countries such as India, China, and Brazil. Faced with this impasse, research for the development of alternative materials to Portland cement is growing around the world. Among these researches, those related to alkali-activated materials (AAMs) stand out. AAMs are considered more sustainable than Portland cement because emit less CO2 during their production process. In addition, the raw materials used in its development are generally wastes from other industrial processes. Sugarcane bagasse ash (SCBA) is an example of residue generated on a large scale in Brazil and with great potential for use in the production of AAMs. Therefore, the present work seeks to develop AAMs using SCBA as an exclusive precursor. For this, the material's viability was verified through physical, mechanical, morphological, and calorimetric tests. As a result, concluded that SCBA is a viable precursor for AAMs, promoting sustainability and innovation in the field of construction materials. In addition, the main mechanism of the reaction of SCBA pastes is the diffusion process, independent of paste formulation and the silicate is crucial for the degree of reaction at early age. At the same time, the compressive strength and microstructure are strongly dependent on alkalis and silicate content and SiO2/Na2O proportions around 1.0 are the optimum point for SCBA pastes.
Propolis is a hive product prepared by honeybees (Apis mellifera L.) widely used in pharmaceutical and food preparations that plays beneficial roles beyond basic nutrition and therapeutic properties. ...These benefits are related with its quality, which depends on various factors, such as geographical origin, botanical sources, collecting seasons, races of honeybees, climatic conditions and also the method of harvest. In this sense, it would be helpful the implementation of a simple, fast and reliable analytical methodology for quality monitoring of propolis samples as a traceability tool of its geographical origin. Thus, this work proposes the use of digital images and chemometrics for the classification of raw propolis from six different geographical origins of the Buenos Aires Province, Argentina. For this purpose, different combinations between a color model (Grayscale, RGB and HSI) and a multivariate classifier (PCA–LDA, SIMCA, kNN, PLS-DA and SPA–LDA) were tested. The best analytical performance was achieved by SPA–LDA using Intensity histograms, classifying correctly a 100% of the samples in both training and test sets, taking in account the 27 variables selected by SPA. As a consequence, the proposed methodology serves to support local apiculturists, guaranteeing the offer of products with a clear indication of geographical origin, and enhancing regional capabilities.
•Geographical origins of Argentine propolis under study•An analytical methodology based on digital images and chemometrics is described.•RGB, HSI and Grayscale histograms were used as analytical information.•Evaluations using PCA–LDA, SIMCA, kNN, PLS-DA and SPA–LDA•Significantly better results were obtained with SPA–LDA variable selection.
Abstract In many places of the world, medicinal plants represent the only form of treatment for various diseases. This work aimed to determine and correlate minerals of infusions and leaves of ...medicinal plants grown in Northeastern Brazil. Principal component and hierarchical cluster analysis and Pearson correlation were performed. The higher content of Na was for Ocimum basilicum L. (94.3 mg/100g) and Datura stramonium L. (91.6 mg/100g). The plants examined had low levels of K in infusions. All samples contain Mg at significant levels. The cluster analysis divided the medicinal plants into three groups, associated with Passiflora edulis, Capraria biflora and Phyllanthus amarus. Ca and Al were the minerals that contributed most to an association between the plants in principal component 1; while K, Na and Mg contributed most in principal component 2. Furthermore, the high percentage of extraction, mainly Ca and Mg, suggests these plants could be used as potential mineral supplements.
Abstract Nutritionally, cheese and other dairy products have been highlighted especially as a calcium source. Access to minerals is dependent on variables related to diet, lifestyle, and also the ...health status. This study aimed to evaluate the bioaccessibility and calcium partition in Minas Padrão cheese over its ripening period for experimentally obtained samples. The cheese of the study has been manufactured using two different technologies (A and B). Also to evaluate the evolution of pH over cheese ripening and the influence of calcium partitions in its bioaccessibility along the cheese ripening period. The mean values found for total calcium content were (549 mg⋅100 g-1 – A and 644 mg⋅100 g-1 – B). For calcium in the aqueous phase on average 460 mg⋅100 g-1 – A and 404 mg⋅100 g-1 – B. These and other changes found are possibly due to physicochemical and biochemical changes, especially with respect to pH variations. Calcium bioaccessibility decreased in the beginning and then incresed in the end of the ripening period. The results obtained in this work hopefully may allow further studies and the development of products in which calcium bioaccessibility might be indicated on the product`s label accordingly to its ripening time.
Plant-based beverages are often poor in nutrients, and fermentation can be a tool to solve this issue. This work aimed to study the fermentation kinetics and symbiotic potential of kefir and kombucha ...in cashew nut beverages (CNB). Three samples were formulated with CNB, and each sample received a different inoculum: 100% kefir, 50/50% kefir, kombucha, and 100% kombucha. They fermented for 72 h at 28 °C, and aliquots were analyzed at different times. The mixed cultures did not influence the production of glucuronic acid, but it was more efficient in consuming oligosaccharides. No acute toxicity was reported with zebrafish, but open camp assay pointed to lower locomotor action in mixed and 100% kombucha samples, which suggests probiotic activity. The sugar contents got lower with time within the 50/50% sample. Fermented cashew nut-based beverages can be a healthy alternative to bring new flavors and textures to cashew nut based beverages, which can be explored in cooking and in the creation of new recipes.
•Kombucha and kefir together enhanced oligosaccharide hydrolysis in cashew nut milk.•Mixed cultures did not optimize functional acids production.•Zebrafish open field assay had changes in motricity, suggesting probiotic activity.•Higher results in open field tests are related to higher sugar content.
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