1,303 research outputs found
A relativistic quantum broadcast channel
We investigate the transmission of classical and quantum information between
three observers in a general globally hyperbolic spacetime using a quantum
scalar field as a communication channel. We build a model for a quantum
broadcast channel in which one observer (sender) wishes to transmit (classical
and quantum) information to two other observers (receivers). They possess some
localized two-level quantum system (a qubit) that can interact with the quantum
field in order to prepare an input or receive the output of this channel. The
field is supposed to be in an arbitrary quasifree state, the three observers
may be in arbitrary states of motion, and no choice of representation of the
field canonical commutation relations is made. The interaction of the field and
qubits is such that it allows us to obtain the map that describes this channel
in a non-perturbative manner. We conclude by analyzing the rates at which
information can be transmitted through this channel and by investigating
relativistic causality effects on such rates.Comment: 15 pages, 1 figur
Filogenia dos genes glta e glnII como suporte para a classificação de espécies no gênero Rhizobium.
Limited vegetative compatibility as a cause of somatic recombination in: Trichoderma pseudokoningii.
With the aim of a better characterization of the somatic recombination process in Trichoderma pseudokoningii, a progeny from crossings between T. pseudokoningii strains contrasting for auxotroph markers was characterized by RAPD markers and PFGE (electrophoretic karyotype). Cytological studies of the conidia, conidiogenesis and heterokaryotic colonies were also performed. The genotypes of the majority of the recombinant strains analyzed were similar to only one of the parental strains and the low frequency of polymorphic RAPD bands suggested that the nuclear fusions may not occur into the heterokaryon. In some heterokaryotic regions the existence of intensely staining hyphae might be related to cell death. We proposed that a mechanism of somatic recombination other than parasexuality might occur, being related to limited vegetative compatibility after postfusion events, as described for other Trichoderma species
Expressão dos genes nodC, nodW e nopP em Bradyrhizobium japonicum estirpe CPAC 15 avaliada por RT-qPCR.
Resumo O objetivo deste trabalho foi avaliar a expressão, por RT-qPCR, dos genes de nodulação nodC e nodW e do gene nopP da estirpe CPAC 15, que provavelmente atuam na infecção das raízes da soja. Foram realizados dois experimentos. No primeiro, a expressão dos genes foi avaliada nas células após a incubação com genisteína por 15 min, 1, 4 e 8 horas. Os resultados revelaram que os três genes apresentaram maior expressão imediatamente após o contato com o indutor (15 min). No segundo experimento, a bactéria foi cultivada na presença de indutores (genisteína ou exsudatos de sementes de soja) por 48 horas. A expressão dos três genes foi maior na presença de genisteína, com valores de expressão para nodC, nodW e nopP superiores ao controle. Os resultados obtidos confirmam a funcionalidade dos três genes na estirpe CPAC 15, com ênfase para o nopP, cuja funcionalidade em Bradyrhizobium japonicum foi descrita pela primeira vez. Termos para indexação: Glycine max, flavonoides, genes de nodulação, sistema de secreção tipo III
Área do piquete e taxa de lotação no pastejo rotacionado.
ABSTRACT: During the last two decades, rotational grazing has been increasingly adopted in cattle farms in the Cerrado Region. However, many farmers and extensionists are still having problems in designing efficient pastoral systems based on rotational grazing. This paper briefly describes the basic concepts of this grazing method and provides key steps to be followed in planning pasture area and stocking rate in rotational grazing.bitstream/CPAC-2009/27320/1/comtec_101.pd
Circular Food Behaviors : A Literature Review
Consumer behavior is crucial in the transition towards circular food systems. Studies so far investigate isolated circular food behaviors, but it is still unclear how the literature comprehensively addresses these behaviors. This paper provides an overview of the literature on circular food behaviors. Following a semi-systematic literature review, we analyze 46 papers related to circular food behaviors. We summarize their main features, categorize the behaviors, and propose a future research agenda. Results show the novelty and quick popularity of the topic, a dispersion across sustainability and agri-food journals, the manuscripts’ goals related to consumption, a predominance of empirical data collection in Europe, a focus on behaviors related to protein alternatives, food waste, and upcycled foods, and the importance of communication and consumers’ education. We categorize and characterize three types of circular food behaviors: linear, transitioning, and circular behaviors. Circular behaviors (i) are part of a systemic circular economy view, (ii) define consumers as “doers” or “prosumers”, (iii) pursue long-term sustainability goals, (iv) show a high engagement of skilled consumers, and (v) are supported by technologies. Future research should consider the social dimension of sustainability and pursue a systemic view of circular food behaviors. We suggest that a circular food-related lifestyle may incorporate the recommended directions.© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).fi=vertaisarvioitu|en=peerReviewed
Transferência horizontal de genes simbióticos de estirpes inoculantes de B. japonicum para estirpes de rizóbios nativas dos solos dos Cerrados.
Avaliação da eficiência na fixação biológica do nitrogênio com a cultura da soja e caracterização genotípica e da diversidade de estirpes de Bradyrhizobium japonicum.
The Dynamics of the Innovation System for Functional Foods in South Brazil
This study aims at identifying the dynamics of the innovation system for functional foods (FF) in Rio Grande do Sul, Brazil. Functional food is any healthy food claimed to have a health-promoting or disease-preventing property beyond the basic function of supplying nutrients. Health has been named as the most significant trend and innovation driver in the global food and drinks market. Brazil is one of the leading countries in food production and consumption, and the market for functional foods have been growing 10% per year, three times more than the market for conventional foods. Although this food category is considered mature in some developed markets (such as in Japan, in the Nordic countries and in the U.S), it is still unknown for many consumers, especially those located in developing countries. On the other hand, functional foods has been attracting the attention of multinationals and local food industries, since innovation can significantly impact on their competitive advantages. Therefore, in this study, first we are going to investigate consumers’ motivations, attitudes and intention to buy functional foods, since the market demands a better understanding of this trend. A survey with 450 consumers was conducted and provided quantitative insights. Secondly, we identified the availability of functional food products in the local retail market, through observation techniques. Our aim was to confront consumers’ needs with local food companies’ market supply. In a further stage, we are going to analyse the functioning of this innovation system, describing the agents involved in this context and their relations through in-depth interviews with local representatives (stakeholders). Innovation system is here understood as the set of distinct institutions which jointly and individually contribute to the development and diffusion of new technologies and which provides the framework within which governments form and implement policies to influence the innovation process. As such "it is a system of interconnected institutions to create, store and transfer the knowledge, skills and artefacts which define new technologies." (Metcalfe, 1995). Hence, we are investigating issues such as: Are local food companies ready to innovate in such a competitive and dynamic scenario? How can this system respond to consumers’ demands? Are there conditions for an innovative food network in South Brazil? Our contributions help to shed light into these questions. Preliminary results indicate that the innovation system for functional foods in Rio Grande do Sul is incipient, but it is developing fast. Stronger governance and co-ordination strategies are needed. There are few local functional food products in the market, but those are attractive to consumers and indicate promising opportunities. The survey shows that interviewed consumers presented positive attitudes towards functional foods and enough purchasing power to buy it. Nutritionists and other health professionals have high credibility and could help inform consumers about the benefits of particular categories of functional foods. Food industry itself is not regarded as the most trustworthy source. Finally, this study shows that the understanding of Brazilian consumers is fundamental to help food companies define their strategies. To map the most accepted categories of functional foods is also important, aiming to avoid the "tentative and error" approach
Diversidade de estirpes de Bradyrhizobium isoladas de diferentes leguminosas, com base na análise do gene ribossomal 16S e dos genes de nodulação nodY/KA.
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