Training samples from open data for satellite imagery classification: Using K-means clustering algorithm

To create a land use/land cover (LULC) map from a satellite image, we can follow a supervised classification approach if we know what classes exist in the study area and if we have representative training samples for each class. However, in heterogeneous biophysical environments, the wide range of spectral signatures among LULC classes can bias the classification results. In this study, we generated training samples from the official 2015 Portuguese Land Cover Map (COS). In spite of the viability of this source of information (official reference data), we faced some problems with corrupted data and an unbalanced number of training samples per class. As such, we explored the K-means clustering technique in order to understand whether the data had critical issues and to select the most representative training samples by class for satellite imagery classification. We investigated the potential of this technique for LULC classification in a predominantly rural region characterized by a mixed agro-silvo-pastoral environment, which means there is a broad range of spectral signatures for each LULC class. Two image classifications for 2015 were performed using the random forest classifier. The first was done by using the most representative training samples selected from the statistical analysis, and the other was done by using the full generated training set (original training set). Ultimately, the present study demonstrates the improvements in overall accuracy between both image classifications (+8%), showing that the applied methodology has a positive impact on the results.info:eu-repo/semantics/publishedVersio

Long-Term Satellite Image Time-Series for Land Use/Land Cover Change Detection Using Refined Open Source Data in a Rural Region

The increasing availability and volume of remote sensing data, such as Landsat satellite images, have allowed the multidimensional analysis of land use/land cover (LULC) changes. However, the performance of image classification is highly dependent on the quality and quantity of the training set and its temporal continuity, which may a ect the accuracy of the classification and bias the analysis of the LULC changes. In this study, we intended to apply a long-term LULC analysis in a rural region based on a Landsat time series of 21 years (1995 to 2015). Here, we investigated the use of open LULC source data to provide training samples and the application of the K-means clustering technique to refine the broad range of spectral signatures for each LULC class. Experiments were conducted on a predominantly rural region characterized by a mixed agro-silvo-pastoral environment. The open source data of the o cial Portuguese LULC map (Carta de Uso e Ocupação do Solo, COS) from 1995, 2007, 2010, and 2015 were integrated to generate the training samples for the entire period of analysis. The time series was computed from Landsat data based on the normalized di erence vegetation index and normalized di erence water index, using 221 Landsat images. The Time-Weighted Dynamic Time Warping (TWDTW) classifier was used, since it accounts for LULC-type seasonality and has already achieved promising overall accuracy values for classifications based on time series. The results revealed that the proposed method was e cient in classifying a long-term satellite time-series with an overall accuracy of 76%, providing insights into the main LULC changes that occurred over 21 years.info:eu-repo/semantics/publishedVersio

O clube de pais leitores do Agrupamento Vertical de Maria Lamas

Dissertação de Mestrado em Gestão da Informação e Bibliotecas Escolares apresentada à Universidade AbertaO trabalho de investigação apresentado assenta na criação e organização de um Clube de Pais Leitores na Escola do Ensino Básico do Primeiro Ciclo – EB1 dos Castelos – Agrupamento Vertical de Maria Lamas, que tem como objectivo principal a promoção de hábitos de leitura nos alunos e o envolvimento na dinâmica das relações entre escola e família. Com esta intenção promoveu-se a cooperação entre escola-família-biblioteca escolar. Colocou-se o enfoque num trabalho comum e comunicacional que favorecesse a relação e a cooperação entre a tríade mencionada e promovesse a leitura como prazer. As principais linhas de força que nortearam este projecto vinculam-se às quatro principais acções destacadas no quadro teórico-conceptual desta pesquisa: a leitura como uma prioridade na educação; os conceitos de leitura e literacia; a leitura como condição para o exercício da cidadania; e a interacção entre escola-família-biblioteca escolar. O trabalho empírico desenvolveu-se em torno da figura do contador de histórias apoiado numa metodologia de análise qualitativa, de cariz etnográfico, associada a uma observação participante. Esta metodologia de acção-investigação, permitiu-nos mergulhar, envolver, viajar, reencontrar e reescrever esta narrativa vivida ao longo do ano lectivo de 2007/08 com um grupo de seis pais, em contexto escolar, na biblioteca da escola. Esta narrativa foi construída, analisada e interpretada, a partir de diários de bordo dos participantes no projecto, de grelhas de observação, imagens videográficas, fotográficas e fonográficas, de mapas mentais e de encontros, que descrevem e explicam a dimensão de que se revestiu esta nossa procura de sentido. Os resultados obtidos são indicadores do elevado grau de relevância e de participação atingidas, bem como do impacto transformador desta acção-investigação enquanto via promotora e facilitadora da comunicação e, portanto, da educação para a sensibilidade e, consequentemente, para a cidadania de todos os intervenientes. A Mandala “A Magia da Palavra”, que acompanha cada uma das dez actividades descritas, constituiu-se como ideia geradora e dela nasceu uma outra Mandala, a Mandala espiralante do Clube dos Pais Leitores, traduzindo valores e sentimentos comuns que emergem da interpretação do projecto

Tratamento de Dados Open source para Classificação de Imagens de Satélite

A elaboração, com elevada precisão, de mapas de uso e ocupação do solo, através de imagens de satélite e métodos de classificação supervisionados depende, em grande medida, das amostras. Neste sentido, a disponibilidade de informação aberta e grátis oficial é particularmente relevante, uma vez que possibilita um conhecimento mais aprofundado sobre a paisagem do local em estudo e, também, a aplicação de classificações supervisionadas. Todavia, em ambientes biofísicos de elevada heterogeneidade, a ampla gama de assinaturas espectrais e a pequena variação destas entre as classes de uso e ocupação do solo poderá influenciar, de forma menos positiva, a produção destes mapas (Viana et al., 2019). Além desta questão existem, também, problemas relacionados com a informação de base utilizada para gerar as amostras de treino. No presente estudo, a carta de uso e ocupação do solo portuguesa (COS) de 2015 consistiu na informação de base para elaboração das amostras de treino. Desta forma, considerando que na COS as classes são representadas por polígonos que incluem elementos que, na verdade, não correspondem à classe propriamente dita (i.e. estradas de terra batida em torno de campos de cultivo), torna-se particularmente importante a aplicação de metodologias que permitam, a priori, analisar as amostras e, se necessário, proceder ao tratamento destas. Deste modo, é explorada a técnica de classificação por grupos (k-means) em ambiente R com recurso ao tclust package, no sentido de analisar e selecionar as amostras mais representativas de cada classe a classificar (Cuesta-Albertos et al.,1997; Fritz, García-Escudero & Mayo- Iscar, 2012). O presente estudo investiga o potencial desta técnica nas classificações supervisionadas de imagens de satélite numa região predominantemente rural caracterizada por uma mistura de ambientes agro-silvo-pastoris. Assim, realizou-se duas classificações para 2015: i) com as amostras originais ii) com as amostras selecionadas. Por fim, as experiências realizadas resultaram numa melhoria da precisão da classificação, (8%) demonstrando, assim, que a metodologia aplicada evidenciou um impacto positivo nos resultados.info:eu-repo/semantics/publishedVersio

A comprehensive look into the volatile exometabolome of enteroxic and non-enterotoxic Staphylococcus aureus strains

Staphylococcal food poisoning is a disease that originates significant health and economic losses and is caused by Staphylococcus aureus strains able to produce enterotoxins. The aim of this work is to go further on the study of the volatile exometabolome of S. aureus using an advanced gas chromatographic technique. Enterotoxic and non-enterotoxic strains were assessed. The volatile exometabolome profile comprised 240 volatiles belonging to ten chemical families. This volatiles were mainly by-products of branched-chain amino acids and methionine degradation, pyruvate metabolism, diacetyl pathway, oxidative stress and carotenoid cleavage. Metabolites released by the first two pathways were produced in higher contents by the enterotoxic strains. This study add further insights to S. aureus volatile exometabolome, and also shows that by applying it, it is possible to distinguish strains of S. aureus by the number of produced enterotoxins, which is especially important from the food safety point of view.publishe

Production of high added value products from eggshells

There are an increasing number of food companies addressing sustainable-manufacturing practices as part of social responsibility reporting. The egg processing industry produces several tons of eggshell residues which are a major environmental problem and represent a significant cost for these industries (ca. 0.6 % of sales). The main goal of this work is to produce high added value products, namely collagen and bioactive peptides, using the remnant of collagen extraction from the eggshell membrane. The target market of the products obtained is the biomedical, pharmaceutical, cosmetics and food industry. The separation of the shell and the membrane was optimized and a chemical-physical process was performed having a yield of 9 % (w membrane/w shell). Times and yields for different separation methods were calculated and the economic viability of the process was studied. In order to optimize collagen extraction from the eggshell membranes several variables were studied (e.g. temperature, enzyme concentration and time). The collagen obtained was separated using saline precipitation steps and different collagen types were identified. The collagen types were visualized using SDS-electrophoresis and total quantification of collagen was made by hydroxyproline method. Moreover, the residue after collagen extraction was further digested with different enzymes, namely pancreatin, tripsin and lysin and the peptides profile was determined by HPLC-UV method. The results showed promising strategies for using this technology at industrial scale as an economic viable technology for producing high added value products from eggshells membranes. This technology will equally contribute to reducing the environmental problem associated with these residues

Production, characterization and application of activated carbon from brewer’s spent grain lignin

Different types of activated carbon were prepared by chemical activation of brewer’s spent grain (BSG) lignin using H3PO4 at various acid/lignin ratios (1, 2, or 3 g/g) and carbonization temperatures (300, 450, or 600 °C), according to a 22 full-factorial design. The resulting materials were characterized with regard to their surface area, pore volume, and pore size distribution, and used for detoxification of BSG hemicellulosic hydrolysate (a mixture of sugars, phenolic compounds, metallic ions, among other compounds). BSG carbons presented BET surface areas between 33 and 692 m2/g, and micro- and mesopores with volumes between 0.058 and 0.453 cm3/g. The carbons showed high capacity for adsorption of metallic ions, mainly nickel, iron, chromium, and silicon. The concentration of phenolic compounds and color were also reduced by these sorbents. These results suggest that activated carbons with characteristics similar to those commercially found and high adsorption capacity can be produced from BSG lignin.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq Brazil)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Activated carbon production from brewer’s spent grain lignin

Activated carbons are adsorbents that are industrially used in multiple processes for product separation and purification, and for the treatment of liquid and gaseous effluents. Despite its frequent use in the water and waste industries, activated carbons remain an expensive material. In view of the high cost and the tedious procedures for the preparation and regeneration of activated carbons, there is a continuing search for low-cost potential adsorbents. The preparation of activated carbons from lignin is an attractive way of giving added value to this material, which is mainly used as in-house fuel for the recovery of both energy and residual inorganic matter. Over the past few decades, some works have been done on the activation of agricultural lignocellulosic waste materials to carbons, due to their low cost and high availability. Nevertheless, there is not any literature report about the activated carbon production from brewer’s spent grain (BSG) lignin. Use of BSG lignin as starting material for activated carbon production is interesting because BSG (the main brewery by-product) is produced in large amounts during all year, and is a lignin-rich material. Lignin can be converted in activated carbon by physical or chemical activation, the last one being more amply used than physical activation, because it requires lower activation temperatures and gives higher product yields. The purpose of the present work was to prepare activated carbon from BSG lignin, by chemical activation using phosphoric acid as impregnating agent, and to examine the influence of preparation conditions (acid/lignin ratio and carbonization temperature) on the textural characteristics of the materials produced (surface area, volume of pores, and pores size distribution) as well as on its adsorption capacities. Chemical activation of BSG lignin using phosphoric acid as impregnating agent was performed at various acid/lignin ratios (1, 2, or 3 g/g) and carbonization temperatures (300, 450, or 600 ºC), according to a 22 full factorial design. The resulting materials were characterized (regarding the surface area, volume of pores, and pores size distribution), and used for detoxification of the BSG hemicellulosic hydrolysate, which consists in a mixture of sugars, phenolic compounds, metallic ions, among other compounds. BSG carbons presented BET surface areas between 33 and 692 m2/g, and volume of pores between 0.058 and 0.453 cm3/g, which generally consisted in micro and mesopores. Adsorption capacity also varied to each carbon, according to the used activation condition. However, all of them showed high capacity for adsorption of metallic ions, mainly nickel, iron, chromium and silicon. In most of the cases, the BSG carbons efficiency for removal of these metals was higher than that obtained when using a commercial carbon sample. Phenolic compounds concentration and color were also reduced by using these sorbents, and the sugars content was practically not affected, which is benefic if the hydrolysate use in bioconversion processes is desired. The present work allowed to conclude that it is possible to produce activated carbons with good efficiency for phenolic compounds and metallic ions removal (mainly Ni, Fe, Cr, and Si), by chemical activation of the BSG lignin. The adsorption capacity of the carbons compared well and even favorably with that of a commercial activated carbon, suggesting that they have potential to be successfully used in detoxification processes in substitution of commercial sorbents. Regarding to the preparation of these activated carbons, an impregnation ratio and activation temperature of 3 g H3PO4/g lignin and 600 ºC, respectively, was the best combination of operating conditions leading to activated carbons with good capacity for adsorption of different toxic compounds. Acknowledgements: CAPES, FAPESP and CNPq (Brazil)

The prognostic value of worsening renal function and its timing

Copyright © 2023 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.INTRODUCTION: Acute decompensated heart failure (ADHF) admissions are frequently complicated by different patterns of serum creatinine (SCr) elevation. We aimed to assess the prognostic impact of worsening renal function (WRF) based on the timing of its occurrence. METHODS: This was a retrospective cohort of patients admitted for ADHF. Standard WRF was defined as an increase in SCr of ≥0.3 mg/dl during hospitalization. WRF timing was classified as early (within 48 hours of admission) or late (>48 hours). Acute kidney injury (AKI) at admission was defined as a rise in SCr of ≥0.3 mg/dl from outpatient baseline measurement to first measurement at admission. The primary endpoint was a composite of all-cause mortality or hospitalization for cardiovascular events at one-year follow-up. RESULTS: Overall, 249 patients were included (mean age 77±11 years, 62% with preserved left ventricular ejection fraction). Early WRF occurred in 49 patients (19.7%) and was associated with a higher risk of the primary outcome (HR 2.49; 95% CI 1.66-3.73), whereas late WRF was not (p=0.411). After stratification for the presence of early WRF and/or AKI at admission, only patients with early WRF but no AKI at admission and patients with both AKI at admission and early WRF showed a higher risk of the primary outcome after multivariate Cox regression. CONCLUSION: Early WRF was associated with a higher risk of the primary outcome. The timing of WRF seems to be an important factor to take into account when considering the prognostic impact of creatinine variations during hospitalization for ADHF.proofepub_ahead_of_prin

Bionomy and Nesting Behavior of the Bee Epanthidium tigrinum (Schrottky, 1905) (Hymenoptera: Megachilidae) in Trap-Nests

About 85% of pollinating bees are solitary, but few are used for agricultural pollination. The Anthidiini tribe looks very promising in Brazil, in the light of ecosystem utility, but  it is still a species with poorly scientific research[EdM1] . To fill this gap studies on the bionomics of this species may collaborate on future studies on use of Epanthidium tigrinum as pollinator. Presented research results aims to describe the bionomy and the biological cycle of the bee E. tigrinum (SCHROTTKY, 1905) in pre-existing cavities. Conventional trap-nests inserted in wooden blocks were placed in covered spaces and daily observations of spontaneous nesting as well as individually tagged bees and nests incubated in B.O.D. were carried out during 11 months in Fortaleza-CE. The results showed that the competition with other species of bees for the pre-existing cavities and the lack of food resources or nest building materials are limiting factors for the establishment of E. tigrinum populations. However, once these problems were remedied, the bees showed multivoltine behavior, nesting throughout the experimental period. Data from 16 nests studied showed that bee foraging began on average at 7:50 a.m., foragers collected pollen in the morning and resin in the afternoon, took on average 15 days to complete a nest and there was a negative correlation with the temperature for the number of nests and for the number of cells constructed. The offspring took 43 days for the emergency, presented sexual ratio of 1.2: 1 (n = 66 emerged bees) and a mortality rate of 18.5%. The number of nests constructed per female ranged from 1 to 4 with an average size of 7.97 mm. It is concluded that E. tigrinum shows potential to rational rearing in trap nests aiming crop pollination. [EdM1