Background
The root system plays a major role in plant growth and development and root system architecture is reported to be the main trait related to plant adaptation to drought. However, ...phenotyping root systems in situ is not suited to high-throughput methods, leading to the development of non-destructive methods for evaluations in more or less controlled root environments. This study used a root phenotyping platform with a panel of 20 japonica rice accessions in order to: (i) assess their genetic diversity for a set of structural and morphological root traits and classify the different types; (ii) analyze the plastic response of their root system to a water deficit at reproductive phase and (iii) explore the ability of the platform for high-throughput phenotyping of root structure and morphology.
Results
High variability for the studied root traits was found in the reduced set of accessions. Using eight selected traits under irrigated conditions, five root clusters were found that differed in root thickness, branching index and the pattern of fine and thick root distribution along the profile. When water deficit occurred at reproductive phase, some accessions significantly reduced root growth compared to the irrigated treatment, while others stimulated it. It was found that root cluster, as defined under irrigated conditions, could not predict the plastic response of roots under drought.
Conclusions
This study revealed the possibility of reconstructing the structure of root systems from scanned images. It was thus possible to significantly class root systems according to simple structural traits, opening up the way for using such a platform for medium to high-throughput phenotyping. The study also highlighted the uncoupling between root structures under non-limiting water conditions and their response to drought.
The objective of this study was to estimate the results of the upland rice (Oryza sativa L.) breeding program conducted by the Brazilian Agricultural Research Corporation (Embrapa) and collaborators ...over the period of 1984 to 2009 covering 25 annual steps of improvement. The best lines generated by this program are evaluated in “value for cultivation and use (VCU) trials.” This study used data from 603 VCU trials conducted in seven Brazilian States. The group of lines entering VCU in each year was taken as a sample of the elite program in that year. Best linear unbiased estimates (BLUEs) of the means of groups were computed, and the regression of the BLUEs on years was taken as an estimate of the efficiency of the breeding program. Traits studied were grain yield (GY), days to flowering (DTF), and plant height (PH). For GY, three phases were described: from 1984 to 1992, the gain for GY was nonsignificant, from 1992 to 2002, the yearly gain was 15.7 kg ha−1 (0.53%), and from 2002 to 2009, the yearly gain was 45.0 kg.ha−1 (1.44%). No evidence of yield plateau was observed. There was a reduction of 0.25 d yr−1 in DTF and 0.52 cm yr−1 in PH, reflecting the change from traditional to modern cultivars. Factors influencing the results of the breeding program in this period are discussed.
O trabalho teve por objetivo analisar as características do percurso teórico-metodológico dos estudos de políticas públicas em abordagem policêntrica e sua aplicabilidade no contexto da economia ...criativa. Para isso, realizou uma revisão sistemática de 24 artigos científicos selecionados nas bases de dados Scopus, Science Direct e Web of Science. Os resultados mostram que a abordagem policêntrica tem sido relatada de forma exitosa nos estudos científicos sobre desenvolvimento, vez que incentiva e democratiza o acesso de atores não-estatais no centro da tomada de decisão, sinalizando a viabilidade de aplicação em políticas públicas endereçadas a setores estratégicos do país, como a economia criativa. Contudo, os estudos deixaram de apresentar detalhadamente os modelos e instrumentos necessários à efetiva implementação de políticas públicas na perspectiva policêntrica, o que revela uma agenda promissora de pesquisas sobre arranjos alternativos de políticas públicas.
To attain success with selection process, the breeders need to understand the genetic variability into each population developed by breeding program. In this purpose, breeders need to estimate the ...variance components and genetic and phenotypic parameters. Besides, they need to have the ability to select simultaneously genetically top progenies for multiple traits. This study used a field trial, with a panel of 198 S
0:2
lowland rice progenies, evaluated in three environments during two years in order to: (
i
) estimate genetic parameters for different traits in a rice breeding population, (
ii
) evaluate the impact of direct selection and selection performed through three selection indices in a rice population developed by recurrent selection, and (
iii
) compare three selection indices using different economic weights with direct and indirect selection. Significant genetic variation was found among progenies for: grain yield, plant height, days to flowering, panicle blast, leaf scald and grain discoloration. The direct selection provided high gains for single trait selection, but this method may results in undesirable changes in related traits. Thus, between the evaluated indices and in comparison, to indirect selection the Mulamba and Mock index provided simultaneously greater gains for all the evaluated traits. Furthermore, we found that when the random weights and
b
-variation index were used as economic weight, it was found lower gains or no gains, showing that the gains attained with Smith and Hazel and Tai indices were linked to economic weights used.
RESUMO Na quase totalidade de sua obra o notável economista e ex-ministro da Cultura, Celso Furtado, exaltou a criatividade da nação brasileira como ativo estratégico para o surgimento de um novo ...modelo de desenvolvimento econômico, sustentável, inclusivo e endógeno. A trajetória analítica deste trabalho recorreu à revisão bibliográfica para destacar as contribuições teóricas de Celso Furtado acerca das potencialidades advindas de uma nova economia, intensiva em criatividade. Por sua vez, os recortes do pensamento furtadiano constituem um instrumento poderoso e atual para (re)pensar as estratégias de superação do subdesenvolvimento do país.
O presente artigo teve por objetivo avaliar o impacto da Lei Aldir Blanc (LAB) nas iniciativas de cultura e economia criativa da cidade de Campo Grande, MS, durante o período pandêmico da covid-19. ...Para isso, recorreu-se à pesquisa bibliográfica e documental, focalizando a dimensão orçamentária da lei até a efetiva implementação como política pública emergencial. Além da dimensão orçamentária, o artigo categoriza as iniciativas e os setores predominantemente apoiados, bem como os impactos nos diferentes projetos selecionados por meio de chamamento público. Os resultados mostram que a LAB, enquanto política emergencial de cultura, foi de fundamental importância na manutenção das iniciativas de cultura e economia criativa durante a covid-19, particularmente nos anos de 2020 e 2021.
In this article, the tribological behavior and energy efficiency of surfaces coated with WC-CoCr/HVOF were evaluated after a laser remelting process, using low and high laser energy densities, ...respectively, 33.3 and 150 J/mm2. The purpose of laser remelting was to adequately modify the microstructure of the coatings and promote better performance during surface sliding. Therefore, the microstructure, phase composition and microhardness of the coatings were investigated, and heat effect on the substrate. During dry and lubricated tribological tests, friction coefficient (COF), wear, and surface roughness also were evaluated. In the dry tests, friction, wear and heat dissipation energies were obtained, which were then correlated with the energy consumed by the tribometer. A HEPR-type biodegradable oil was used in the lubricated tests. The proper formation of W2C and Co3W3C, obtained for the lower energy density, increased the hardness, without weakening the material, while the CrC phase acted as an anti-wear barrier. Whereas for the high energy density, thermal decomposition produced fragile phases, which were easily removed from the matrix during the wear test. The sample tested in as-sprayed condition had a high adhesion and friction compared to the remelted samples. On the remelted surfaces, greater friction stability was obtained. The lower dry friction was not linked to the lower power consumption, a result which was then attributed to the higher heat dissipation from the surface during the tests. Finally, this study proposes a methodology for quantifying the efficiency of sliding surfaces and points to a sustainable solution for tribology.
•An energy-based mathematical model was developed to estimate the sliding efficiency.•A non-linear behavior between laser energy and coating microhardness was obtained.•Laser remelting in the coating lowers COF but not necessarily energy consumption.•The adequate distribution of W2C, Co3W3C and CrC increases the resistance to wear.•The sustainable combination of laser remelting with HEPR oil reduced COF and wear.
This study aimed to identify upland rice cultivars and elite lines that are tolerant to drought and the agronomic traits associated with this tolerance. Forty-one genotypes were evaluated in a ...randomized block design with three replications in experiments with and without water stress at the Experimental Station of Emater, in Porangatu, Goias State, in 2011 and 2012. The first experiment was well-irrigated throughout plant development and the second experiment was irrigated only up to 40 days after emergence, after which water stress was imposed. A multivariate analysis using Wards method was applied, and the genotypes with and without water stress were classified into six and seven clusters, respectively, based on the average yield in the two years of experimentation. The most productive cluster under water stress comprised the genotypes AB062041, Douradão, Guarani, BRS Aimoré, and Tangara. The first four genotypes of this cluster were also ranked in the second most productive cluster under well-irrigated conditions. In the selection for drought tolerance, the genotypes that exhibit precocity, less dense panicles, low sterility and greater 100-grain weight under water stress should be prioritized.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Deep skin burn represents a global morbidity and mortality problem, and the limitation of topical treatment agents has motivated research to development new formulations capable of preventing ...infections and accelerating healing. The aim of this work was to develop and characterize an emulgel based on collagen (COL) and gelatin (GEL) extracted from fish skin associated with Chlorella vulgaris extract (CE) and silver nitrate (AgNO3). COL and GEL were characterized by physicochemical and thermal analyses; and CE by electrophoresis and its antioxidant capacity. Three emulgels formulations were developed: COL (0.5%) + GEL (2.5%) (E1), COL+GEL+CE (1%) (E2), and COL+GEL+CE + AgNO3 (0.1%) (E3). All formulations were characterized by physicochemical, rheology assays, and preclinical analyses: cytotoxicity (in vitro) and healing potential using a burn model in rats. COL and GEL showed typical physicochemical characteristics, and CE presented 1.3 mg/mL of proteins and antioxidant activity of 76%. Emulgels presented a coherent physicochemical profile and pseudoplastic behavior. Preclinical analysis showed concentration‐dependent cytotoxicity against fibroblast and keratinocytes. In addition, all emulgels induced similar percentages of wound contraction and complete wound closure in 28 days. The histopathological analysis showed higher scores for polymorphonuclear cells to E1 and greater neovascularization and re‐epithelialization to E3. Then, E3 formulation has potential to improve burn healing, although its use in a clinical setting requires further studies.
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