110 research outputs found
A influência do centro escolar na prática da atividade física das crianças em comparação com a prática na escola tradicional
Projeto de investigaçãoAtividade física (AF) regular, tal como, andar, dançar ou andar de bicicleta, trás muitos benefícios para a saúde. Pode, por exemplo, reduzir o risco de doenças cardiovasculares, diabetes, osteoporose, ajudar a controlar o peso e a promover o bem-estar psicológico. Para crianças e jovens, a AF inclui recreação, jogos, educação física, ou exercício planeado, no contexto familiar, escolar e atividades comunitárias (WHO, 2011). Atualmente constroem-se cada vez mais centros escolares ao invés de escolas primárias (1º ciclo), como forma de evitar as turmas reduzidas e reunir melhores condições para as crianças. Desta forma o presente estudo tem como principal objectivo perceber qual a influência da integração num Centro Escolar, em comparação com a Escola Primária, para a prática da AF diária da criança, identificando as diferenças e semelhanças. A amostra será composta por 50 alunos de um centro escolar e de 50 alunos de uma escola primária, dos 3º e 4º anos do distrito de Braga. O método utilizado para estudar esta problemática será um inquérito por questionário.Fundação para a Ciência e a Tecnologia (FCT) - unidade de investigação 31
Physical and chemical characterization of yacon (Smallanthus sonchifolius) roots cultivated with different doses of potassium fertilization
The already marked tendency for functional food consumption, low in calories, and with biologically active properties, has been increasing. In this scenario, yacon tuberous roots, with high levels of nutraceutical fructooligosaccharides, gain importance. However, these nutraceutical properties depend on fertilization management. Thus, our study aims to evaluate different doses of potassium fertilization on the physicochemical characteristics of yacon roots. The experimental design consisted of randomized blocks, with 4 replications and 5 treatments: four doses of potassium fertilization (50%; 100%; 150%; 200%) of the reference value, corresponding to 178.7 kg.ha-1; 357.4 kg.ha-1; 536.1 kg.ha-1; 714.8 kg.ha-1 of potassium chloride – (KCl), and a control (soil without fertilization). The chemical features evaluated were pH, total titratable acidity, soluble solids, conductivity, turbidity, moisture and ashes. The texture profile was analyzed through toughness, adhesiveness, cohesiveness, chewability index, elasticity, and gooeyness. Most of the variables were influenced by potassium soil fertilization. Only turbidity, conductivity and gumminess showed no response to the applied doses, not fitting the tested models. Potassium fertilization improved both chemical (higher levels of soluble solids and less acidity) and physical characteristics (less hardness, chewability, cohesiveness, and adhesion) of yacon tuberous roots, bringing greater quality to the final product.
Highlights
Yacon is considered a prebiotic food. Several immunostimulatory characteristics promote antimicrobial, anti-inflammatory, and antioxidant activity.
Potassium is associated with root size, shape, texture, color, flavor, acidity, nutrient transport resistance, nutritional value, and even market value.
Texture constitutes an important factor and quality criterion for the sensory acceptance of food. Thus, the results obtained show that potassium fertilization improves both physical and chemical characteristics of yacon roots.
The best results were observed with the maximum dose of potassium fertilization (357.4 kg.ha-1 of KCl).The already marked tendency for functional food consumption, low in calories, and with biologically active properties, has been increasing. In this scenario, yacon tuberous roots, with high levels of nutraceutical fructooligosaccharides, gain importance. However, these nutraceutical properties depend on fertilization management. Thus, our study aims to evaluate different doses of potassium fertilization on the physicochemical characteristics of yacon roots. The experimental design consisted of randomized blocks, with 4 replications and 5 treatments: four doses of potassium fertilization (50%; 100%; 150%; 200%) of the reference value, corresponding to 178.7 kg.ha-1; 357.4 kg.ha-1; 536.1 kg.ha-1; 714.8 kg.ha-1 of potassium chloride – (KCl), and a control (soil without fertilization). The chemical features evaluated were pH, total titratable acidity, soluble solids, conductivity, turbidity, moisture and ashes. The texture profile was analyzed through toughness, adhesiveness, cohesiveness, chewability index, elasticity, and gooeyness. Most of the variables were influenced by potassium soil fertilization. Only turbidity, conductivity and gumminess showed no response to the applied doses, not fitting the tested models. Potassium fertilization improved both chemical (higher levels of soluble solids and less acidity) and physical characteristics (less hardness, chewability, cohesiveness, and adhesion) of yacon tuberous roots, bringing greater quality to the final product.
Highlights
Yacon is considered a prebiotic food. Several immunostimulatory characteristics promote antimicrobial, anti-inflammatory, and antioxidant activity.
Potassium is associated with root size, shape, texture, color, flavor, acidity, nutrient transport resistance, nutritional value, and even market value.
Texture constitutes an important factor and quality criterion for the sensory acceptance of food. Thus, the results obtained show that potassium fertilization improves both physical and chemical characteristics of yacon roots.
The best results were observed with the maximum dose of potassium fertilization (357.4 kg.ha-1 of KCl)
Leghemoglobin and molybdenum contente in soybean (Glycine max) nodules inoculated with Rhizobium strains of normal and exceptional efficiency
Foram feitos dois experimentos em casa de vegetação, empregando vasos de Leonard esterilizados, com quatro variedades de soja (Glycine max (L.) Merril) inoculadas com uma estirpe de Rhizobium japonicum considerada normal (SM1b) e outra de eficiência excepcional (R54a) para se estudar a correlação entre o teor de leg-hemoglobina e de molibdênio dos nódulos e a fixação simbiótica de nitrogênio. Enquanto a fixação de nitrogênio por grama de nódulos foi aproximadamente o dôbro com a estirpe excepcional, o teor de leg-hemoglobina dos nódulos por ela formados foi em média 27% maior, sendo, mesmo assim, altamente significativa a diferença entre as duas estirpes, nos dois experimentos. Entretanto, nas plantas inoculadas com a mesma estirpe, não houve correlação entre o teor de leg-hemoglobina e a eficiência nodular. O teor de molibdênio dos nódulos formados pela estirpe excepcional R54a, foi, aproximadamente, duas vêzes maior que o dos nódulos formados pela estirpe normal SM1b, correspondendo, assim, à diferença na eficiência nodular entre as duas estirpes.Two greenhouse experiments were carried out in sterilized Leonard jars with four soybean varieties inoculated with a Rhizobium strain considered normal (SM1b) and another with exceptional efficiency (R54a), to study the correlation of leghemoglobin and molybdenum content of the nodules and nitrogen fixation. Nitrogen fixation per unit nodule weight as evaluated by the regression of total plant nitrogen with nodule weight (Fig. 1) was about twice as high with the exceptional strain. The increase in molybdenum content was correspondent to the higher nodule efficiency being twice as high in nodules formed by the exceptional strain. It was thus suggested these nodules having doubled nitrogenase content. The increase in leghemoglobin content, however, was not correspondent to the increase in nodule efficiency. An increase of 136% in average of the nodule efficiency was accompanied by an increase of only 27% of the leghemoglobin content (Table 1, Fig. 2). Within strains there was no correlation of either molybdenum or leghemoglobin content with nodule efficiency. It was therefore suggested that for each group of strains nitrogenase and hemoglobin content in nodules and nodule efficiency are theoretically constant, variations being due to the experimental error. The difference between normal and exceptional strains of Rhizobium japonicum would then be due to a difference in the nitrogen fixing system or in the mechanism of incorporation of NH3
Yacon (Smallanthus sonchifolius), propagation from rhizophores with different numbers of buds
Yacon (Smallanthus sonchifolius) is a plant of Andean origin currently cultivated and consumed in several parts of the world for having numerous nutraceutical properties. An increasing interest in its cultivation demands advanced technical information on this crop, still scarce. Considering this, our study aimed to evaluate the propagation of yacon by rhizophores with different bud number. The experiment was conducted in two phases: the first phase was developed in a seedling nursery, using a completely randomized design with four treatments and 50 repetitions. The treatments consisted of rhizophores with: one to two buds (T1), three to four buds (T2), five to six buds (T3), and seven to eight buds (T4). The second phase was performed in the field with random blocks, four treatments, four repetitions, and the same treatments of the first phase. The following morphological and growth characteristics were assessed: plant height, stem diameter, number of leaves, number of stems per plant, Dickson quality index (DQI), leaf area, leaf dry mass, rhizophores, tuberous root, and productivity. The following physiological features were also analyzed: chlorophyll content (FCI – Falker chlorophyll index), net carbon assimilation rate, leaf transpiration, stomatal conductance, internal carbon concentration, water use efficiency and instantaneous carboxylation efficiency. Seedlings from rhizophores with three to four buds presented the best morphological and growth characteristics, DQI = 0.47 and good performance in the field. In addition, the plants originated from this material (rhizophores with three to four buds) showed greater accumulation of dry matter in the aerial part and tuberous roots, and consequently higher productivity in fresh tuberous roots, constituiting a suitable propagation form for the cultivation of yacon.
Highlights:
Seedlings from rhizophores with three to four buds presented the best morphological and growth characteristics.
The results indicate differences in photosynthetic capacity among seedlings.
Possibility of estimating the CO2 assimilation in yacon plants through chlorophyll contents, determined by "ClorofiLOG" (model FL1030, Falker), a device that has lower cost and simple handling than other photosynthesis analyzers, like IRGA Licor 6400XT, representing a significant methodological contribution.
Study shows that the number of buds in the yacon propagule (rhizophores) has a direct influence, from seedling phase to final production and that their weight should not be a factor for selection.Yacon (Smallanthus sonchifolius) is a plant of Andean origin currently cultivated and consumed in several parts of the world for having numerous nutraceutical properties. An increasing interest in its cultivation demands advanced technical information on this crop, still scarce. Considering this, our study aimed to evaluate the propagation of yacon by rhizophores with different bud number. The experiment was conducted in two phases: the first phase was developed in a seedling nursery, using a completely randomized design with four treatments and 50 repetitions. The treatments consisted of rhizophores with: one to two buds (T1), three to four buds (T2), five to six buds (T3), and seven to eight buds (T4). The second phase was performed in the field with random blocks, four treatments, four repetitions, and the same treatments of the first phase. The following morphological and growth characteristics were assessed: plant height, stem diameter, number of leaves, number of stems per plant, Dickson quality index (DQI), leaf area, leaf dry mass, rhizophores, tuberous root, and productivity. The following physiological features were also analyzed: chlorophyll content (FCI – Falker chlorophyll index), net carbon assimilation rate, leaf transpiration, stomatal conductance, internal carbon concentration, water use efficiency and instantaneous carboxylation efficiency. Seedlings from rhizophores with three to four buds presented the best morphological and growth characteristics, DQI = 0.47 and good performance in the field. In addition, the plants originated from this material (rhizophores with three to four buds) showed greater accumulation of dry matter in the aerial part and tuberous roots, and consequently higher productivity in fresh tuberous roots, constituiting a suitable propagation form for the cultivation of yacon.
Highlights:
Seedlings from rhizophores with three to four buds presented the best morphological and growth characteristics.
The results indicate differences in photosynthetic capacity among seedlings.
Possibility of estimating the CO2 assimilation in yacon plants through chlorophyll contents, determined by "ClorofiLOG" (model FL1030, Falker), a device that has lower cost and simple handling than other photosynthesis analyzers, like IRGA Licor 6400XT, representing a significant methodological contribution.
Study shows that the number of buds in the yacon propagule (rhizophores) has a direct influence, from seedling phase to final production and that their weight should not be a factor for selection
Virulence Attenuation of Candida albicans Genetic Variants Isolated from a Patient with a Recurrent Bloodstream Infection
The incidence of Candida albicans infections and the relapse episodes after antifungal treatment have increased in recent decades. Recurrences are mainly due to the persistence of the original infecting strain that may present genetic and genomic rearrangements during interaction with the host, reflecting strain adaptation. In this study, four isolates recovered from a patient during recurrent candidemia episodes were genotyped by microsatellite length polymorphism (MLP) and by multilocus sequence typing (MLST) and found to be genetic variants of the same strain. Using experimental mouse infections, a progressive reduction in the virulence of the four isolates was observed, with the first two isolates more virulent than the third and fourth. Additionally, in the mouse model, the first isolate resisted host control more efficiently, resulting in higher kidney fungal burdens and necrosis as compared to the third isolate. The resolution of inflammation was delayed in mice challenged with the first isolate and the message for IFN-γ and TNF-α in the spleen was lower within the first few hours post-infection. Original and recurrent isolates also displayed different phenotypes regarding activity of secreted enzymes and response to stress agents. Overall, the comparative analysis indicated that the virulence decrease of these isolates was related to a lower ability to resist to the host anticandida effector mechanisms. We showed for the first time that C. albicans genetic variants of the same strain, sequentially isolated from an immunocompromised patient, underwent adaptations in the human host that resulted in virulence attenuation when tested in mice
Comparative Genomics Provides Insights into the Taxonomy of Azoarcus and Reveals Separate Origins of Nif Genes in the Proposed Azoarcus and Aromatoleum Genera
© 2021 by the authors.Among other attributes, the Betaproteobacterial genus Azoarcus has biotechnological importance for plant growth-promotion and remediation of petroleum waste-polluted water and soils. It comprises at least two phylogenetically distinct groups. The “plant-associated” group includes strains that are isolated from the rhizosphere or root interior of the C4 plant Kallar Grass, but also strains from soil and/or water; all are considered to be obligate aerobes and all are diazotrophic. The other group (now partly incorporated into the new genus Aromatoleum) comprises a diverse range of species and strains that live in water or soil that is contaminated with petroleum and/or aromatic compounds; all are facultative or obligate anaerobes. Some are diazotrophs. A comparative genome analysis of 32 genomes from 30 Azoarcus-Aromatoleum strains was performed in order to delineate generic boundaries more precisely than the single gene, 16S rRNA, that has been commonly used in bacterial taxonomy. The origin of diazotrophy in Azoarcus-Aromatoleum was also investigated by comparing full-length sequences of nif genes, and by physiological measurements of nitrogenase activity using the acetylene reduction assay. Based on average nucleotide identity (ANI) and whole genome analyses, three major groups could be discerned: (i) Azoarcus comprising Az. communis, Az. indigens and Az. olearius, and two unnamed species complexes, (ii) Aromatoleum Group 1 comprising Ar. anaerobium, Ar. aromaticum, Ar. bremense, and Ar. buckelii, and (iii) Aromatoleum Group 2 comprising Ar. diolicum, Ar. evansii, Ar. petrolei, Ar. toluclasticum, Ar. tolulyticum, Ar. toluolicum, and Ar. toluvorans. Single strain lineages such as Azoarcus sp. KH32C, Az. pumilus, and Az. taiwanensis were also revealed. Full length sequences of nif-cluster genes revealed two groups of diazotrophs in Azoarcus-Aromatoleum with nif being derived from Dechloromonas in Azoarcus sensu stricto (and two Thauera strains) and from Azospira in Aromatoleum Group 2. Diazotrophy was confirmed in several strains, and for the first time in Az. communis LMG5514, Azoarcus sp. TTM-91 and Ar. toluolicum TT. In terms of ecology, with the exception of a few plant-associated strains in Azoarcus (s.s.), across the group, most strains/species are found in soil and water (often contaminated with petroleum or related aromatic compounds), sewage sludge, and seawater. The possession of nar, nap, nir, nor, and nos genes by most Azoarcus-Aromatoleum strains suggests that they have the potential to derive energy through anaerobic nitrate respiration, so this ability cannot be usefully used as a phenotypic marker to distinguish genera. However, the possession of bzd genes indicating the ability to degrade benzoate anaerobically plus the type of diazotrophy (aerobic vs. anaerobic) could, after confirmation of their functionality, be considered as distinguishing phenotypes in any new generic delineations. The taxonomy of the Azoarcus-Aromatoleum group should be revisited; retaining the generic name Azoarcus for its entirety, or creating additional genera are both possible outcomes.This research was funded by the BBSRC-Newton Fund (grant numbers BB/N013476/1
and BB/N003608/1). MC was funded by grant BIO2016-79736-R from the Ministry of Economy and
Competitiveness of Spain.Peer reviewe
Ardra profiles of bacteria and archaea in mangrove sediments with different levels of contamination in the estuarine complex of Paranaguá, Brazil
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4
While the increasing availability of global databases on ecological communities has advanced our knowledge
of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In
the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of
Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus
crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced
environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian
Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by
2050. This means that unless we take immediate action, we will not be able to establish their current status,
much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
Práticas Educomunicativas
Esta publicação pretende divulgar as práticas educomunicativas realizadas em diferentes regiões do país e que estão sendo implantadas por nossos associados. O e-book Práticas Educomunicativas, que visa oferecer um material de uso prático que possa servir de apoio pedagógico em diferentes contextos, escolar ou de ações junto a instituições, apresenta 20 artigos de profissionais e pesquisadores que implementam ações que inter-relacionam comunicação e educação no contexto da educação apontando as experiências e processos de educomunicação e valorizando desta forma, o trabalho realizado por cada educomunicador oferecendo, ao leitor, um material de uso prático que possa servir de apoio pedagógico em diferentes contextos
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