In situ synthesis of magnetite nanoparticles in carrageenan gels

Magnetite nanoparticles have been successfully synthesized in the presence of carrageenan polysaccharides using an in situ coprecipitation method. Iron coordination to the sulfate groups of the polysaccharide was confirmed by FTIR. The polysaccharide type ( , é, or ì) and concentration have been varied and their effects on particle morphology and chemical stability of the resultant nanocomposite investigated. The presence of carrageenan induces the formation of smaller particles, compared to those formed in the absence of polymer, and their average size depends on the nature and concentration of the polysaccharide used. The chemical stability of magnetite nanoparticles toward oxidation was also seen to depend on biopolymer type with magnetite formed in é-carrageenan showing the highest chemical stability. A general tendency toward lower stability is observed as the polysaccharide concentration is increased. It is suggested that magnetite chemical stability in the carrageenan composites is determined by a fine balance between particle size and gel strength, the latter determining oxygen diffusion rates through the medium

Professional Training in Beekeeping: A Cross-Country Survey to Identify Learning Opportunities

first_pagesettingsOrder Article Reprints Open AccessArticle Professional Training in Beekeeping: A Cross-Country Survey to Identify Learning Opportunities by Raquel P. F. Guiné 1ORCID,Jorge Oliveira 1ORCID,Catarina Coelho 1,2,*ORCID,Daniela Teixeira Costa 1,Paula Correia 1ORCID,Helena Esteves Correia 1ORCID,Bjørn Dahle 3,Melissa Oddie 3,Risto Raimets 4,Reet Karise 4ORCID,Luis Tourino 5,Salvatore Basile 6,Emilio Buonomo 6,Ivan Stefanic 7 andCristina A. Costa 1ORCID 1 CERNAS Research Centre, Polytechnic Institute of Viseu, 3504-510 Viseu, Portugal 2 CECAV, Animal and Veterinary Research Center, University of Trás-os-Montes e Alto Douro, Quinta de Prados, Apartado 1013, 5000-801 Vila Real, Portugal 3 Norwegian Beekeepers Association, 2040 Kløfta, Norway 4 Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, 51014 Tartu, Estonia 5 Eosa Estrategia y Organización SA, 36202 Vigo, Spain 6 Bio-Distretto Cilento, 84052 Salerno, Italy 7 Tera Tehnopolis, 31000 Osijek, Croatia * Author to whom correspondence should be addressed. Sustainability 2023, 15(11), 8953; https://doi.org/10.3390/su15118953 Received: 21 April 2023 / Revised: 24 May 2023 / Accepted: 31 May 2023 / Published: 1 June 2023 (This article belongs to the Special Issue Prospects Challenges and Sustainability of the Agri-Food Supply Chain in the New Global Economy II) Download Browse Figures Review Reports Versions Notes Abstract Habitat loss, climate change, and other environmental degradations pose severe challenges to beekeepers. Therefore, this sector needs to rely on updated information so that the intervening actors can deal with the problems. In this context, and assuming that professional training can greatly help those acting in the beekeeping sector, this work intended to investigate the gaps in the updated knowledge of beekeepers and how these can be filled through lifelong learning. The research was conducted in seven European countries (Croatia, Estonia, Finland, Italy, Norway, Portugal, and Spain). The data were collected through a questionnaire survey translated into the native languages of all participating countries. The results revealed that the topics of highest interest are apiary health and pest control and the management of the colonies throughout the year. The beekeepers update their knowledge through family, complemented by professional training, with participants preferring in-person courses as well as, in the workplace or in internships. The learning methodologies they consider most useful are project-based learning and learning through gamification. The videos and paper books or manuals are particularly valued as learning materials, and practical exercises are considered the most helpful assessment format. Finally, considering the effect of sociodemographic variables on the learning experiences and preferences of beekeeping actors, it was observed that the country was the most influential of the variables under study. In conclusion, this work revealed valuable information that should be used to design professional training actions to help the professionals in the beekeeping sector enhance their competencies and be better prepared to manage their activities successfully.info:eu-repo/semantics/publishedVersio

Produtividade e qualidade do melão em função da cobertura do solo no Vale do São Francisco.

Suplemento. Edição dos Trabalhos do 49 Congresso Brasileiro de Olericultura, Águas de Lindóia, ago. 2009

Emergência de plântulas de gliricídia oriundas de sementes armazenadas em diferentes condições.

Com este estudo, objetivou-se avaliar a emergência e o crescimento de plântulas de gliricídia [Gliricidia sepium (Jacq.) Steud] obtidas de sementes conservadas em três tipos de recipientes, diferentes períodos de armazenamento e a aplicação do ácido giberélico GA4 + GA7 (18,8 g/L) e 6-benziladenina (18,8g/L)

Antimicrobial evaluation of strains of Streptococcus Spp. form tilapia cultivated in Sobradinho Lake, Bahia, Brazil.

Tilapia is the second most cultivated fish in the world, the most cultivated in Brazil and is produced mostly in intensive high density systems, which make them susceptible to infectious diseases

Investigation of the Level of Knowledge in Different Countries about Edible Insects: Cluster Segmentation

This study aimed to investigate the level of knowledge about edible insects (EIs) in a sample of people from thirteen countries (Croatia, Greece, Latvia, Lebanon, Lithuania, Mexico, Poland, Portugal, Romania, Serbia, Slovenia, Spain, and Turkey). Data collection was based on a questionnaire survey applied through online tools between July and November 2021. For data analysis, techniques such as factor analysis, cluster analysis, and chi-square tests were used, with a significance level of 5%. A total of 27 items were used to measure knowledge on a five-point Likert scale. Applying factor analysis with principal components and Varimax rotation, a solution that explains about 55% of variance was obtained. This accounts for four factors that retained 22 of the 27 initial items: F1 = Sustainability (8 items), F2 = Nutrition (8 items), F3 = Production Factors (2 items), and F4 = Health Concerns (4 items). Internal consistency was evaluated through Cronbach’s alpha. The cluster analysis consisted of the application of hierarchical methods followed by k-means and produced three clusters (1—‘fearful’, 2—‘farming,’ and 3—‘ecological’ individuals). The characterisation of the clusters revealed that age did not influence cluster membership, while sex, education, country, living environment, professional area, and income all influenced the composition of the clusters. While participants from Mexico and Spain were fewer in the ‘fearful’ cluster, in those from Greece, Latvia, Lebanon, and Turkey, the situation was opposed. Participants from rural areas were mostly in cluster 2, which also included a higher percentage of participants with lower income. Participants from professional areas linked with biology, food, and nutrition were mostly in cluster 3. In this way, we concluded that the level of knowledge about EIs is highly variable according to the individual characteristics, namely that the social and cultural influences of the different countries lead to distinct levels of knowledge and interpretation of information, thus producing divergent approaches to the consumption of insects—some more reluctant and measuring possible risks. In contrast, others consider EIs a good and sustainable protein-food alternative.info:eu-repo/semantics/publishedVersio

Are Consumers Aware of Sustainability Aspects Related to Edible Insects? Results from a Study Involving 14 Countries

In recent years, edible insects have been suggested as an alternative food that is more sustainable compared with other sources of animal protein. However, knowledge about the sustainability aspects associated with this source of food may play a role in convincing consumers to adopt insects as part of their diet. In this context, the present study investigated the level of knowledge about the sustainability of edible insects in a group of people originating from 14 countries, with some naturally entomophagous and others not. To measure the knowledge, 11 items were selected and the scores obtained were tested with statistical tools (t-test for independent samples, analysis of variance—ANOVA) to search for differences according to sociodemographic and socioeconomic characteristics, geographical origin, and consumption habits of edible insects. The obtained results showed that, in general, knowledge is moderate, with the values of the average scores for the 11 items investigated ranging from 0.23 ± 0.99 to 0.66 ± 1.02, on a scale ranging from –2 (=very low knowledge) to 2 (=very high knowledge). The highest scores were found for items relating to the lower use of animal feed and lower emission of greenhouse gases required for the production of insects compared with beef. When investigating the differences between groups of participants, significant differences were generally found, revealing a trend for higher knowledge among males and young adults, for participants residing in urban areas and in countries such as Spain, Mexico, and Poland, and for participants with higher education levels and higher incomes. When testing the influence of consumption variables on the level of knowledge, the results showed a higher knowledge for participants who had already consumed insects or are willing to consume them. Finally, it was observed that higher knowledge was found for participants whose motivation to consume insects related to curiosity, a wish to preserve the planet, the gastronomic characteristics of insects, and their nutritional value. In conclusion, these results clearly indicate a very marked influence of a number of variables on the knowledge about the sustainability of edible insects, and this may be helpful to delineate strategies to effectively raise knowledge and eventually increase the willingness to consider insects as a more sustainable alternative to partially replace other protein foods, even in countries where this is a not a traditional practice.info:eu-repo/semantics/publishedVersio