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1.
J Geophys Res Biogeosci ; 128(4): 2022jg007258, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37457913

RESUMO

Measurements of ecosystem carbon (C) fluxes in temperate forests are concentrated in the Northern Hemisphere, leaving the functionally diverse temperate forests in the Southern Hemisphere underrepresented. Here, we report three years (February 2018-January 2021) of C fluxes, studied with eddy-covariance and closed chamber techniques, in an endangered temperate evergreen rainforest of the long-lived paleoendemic South American conifer Fitzroya cupressoides. Using classification and regression trees we analyzed the most relevant drivers and thresholds of daily net ecosystem exchange (NEE) and soil respiration. The annual NEE showed that the forest was a moderate C sink during the period analyzed (-287±38 g C m-2 year -1). We found that the capacity to capture C of the Fitzroya rainforests in the Coastal Range of southern Chile is optimal under cool and rainy conditions in the early austral spring (October-November) and decreases rapidly towards the summer dry season (January-February) and autumn. Although the studied forest type has a narrow geographical coverage, the gross primary productivity measured at the tower was highly representative of Fitzroya and other rainforests in the region. Our results suggest that C fluxes in paleoendemic cool F. cupressoides forests may be negatively affected by the warming and drying predicted by climate change models, reinforcing the importance of maintaining this and other long-term ecological research sites in the Southern Hemisphere.

2.
Front Psychol ; 12: 719648, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34690877

RESUMO

Science inquiry and modeling activities have been proved to heighten emotional situations; therefore, research about emotions should aim to identify which activities promote student engagement with Science, Technology, Engineering and Mathematics fields through multidimensional models that include emotional and cognitive engagement. This research is focused on science teachers' need to carefully review their classroom instructions to ensure that students are provided with opportunities to develop appropriate understandings of acid/base models (and their concepts). To achieve this, we have implemented a short model-based inquiry acid-base instructional sequence in the context of a TV-spot about chewing gum. A descriptive, non-experimental quantitative methodology with a heuristic (emotional: self-report questionnaire; and cognitive: self-regulation questionnaire) has been used to analyze what Pre-Service Secondary Education Teachers from several Spanish universities recognize to have learned and felt in each activity. Differences regarding knowledge declared by the participants were identified in all the tasks from before to after carrying them out. Furthermore, the results seem to indicate that there are significant relationships between the knowledge and the emotions, being different depending on the skill involved. Significant correlations between emotions have been found. However, there were no significant correlations with either rejection and knowledge or with other emotions, which points to emotional engagement. Generally, no significant differences were identified between emotions and gender or universities, with some exceptions between genders in two tasks. Thus, the results led us to reflect on the instructional sequence implementation's ability to bring awareness to the learning process and how it produces multidimensional engagements.

3.
Molecules ; 26(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069529

RESUMO

Different materials containing carboxylic groups have been functionalized with geranyl-amine molecules by using an EDC/NHS strategy. Chemical modification of the support was confirmed by XRD, UV-spectrophotometer, and FT-IR. This geranyl-functionalized material was successfully applied for four different strategies of site-selective immobilization of proteins at room temperature and aqueous media. A reversible hydrophobic immobilization of proteins (lipases, phosphoglucosidases, or tyrosinase) was performed in neutral pH in yields from 40 to >99%. An increase of the activity in the case of lipases was observed from a range of 2 to 4 times with respect to the initial activity in solution. When chemically or genetically functionalized cysteine enzymes were used, the covalent immobilization, via a selective thiol-alkene reaction, was observed in the presence of geranyl support at pH 8 in lipases in the presence of detergent (to avoid the previous hydrophobic interactions). Covalent attachment was confirmed with no release of protein after immobilization by incubation with hydrophobic molecules. In the case of a selenium-containing enzyme produced by the selenomethionine pathway, the selective immobilization was successfully yielded at acidic pH (pH 5) (89%) much better than at pH 8. In addition, when an azido-enzyme was produced by the azide-homoalanine pathway, the selective immobilization was successful at pH 6 and in the presence of CuI for the click chemistry reaction.


Assuntos
Enzimas Imobilizadas/química , Proteínas/química , Química Click , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
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